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<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"/><title>12.4 Syntax Transformers</title><link rel="stylesheet" type="text/css" href="../scribble.css" title="default"/><link rel="stylesheet" type="text/css" href="extras.css" title="default"/><link rel="stylesheet" type="text/css" href="../racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-style.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../manual-racket.css" title="default"/><link rel="stylesheet" type="text/css" href="../doc-site.css" title="default"/><script type="text/javascript" src="../scribble-common.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../manual-racket.js"></script><script type="text/javascript" src="../doc-site.js"></script><script type="text/javascript" src="../local-redirect/local-redirect.js"></script><script type="text/javascript" src="../local-redirect/local-user-redirect.js"></script><!--[if IE 6]><style type="text/css">.SIEHidden { overflow: hidden; }</style><![endif]--></head><body id="doc-racket-lang-org"><div class="tocset"><div class="tocview"><div class="tocviewlist tocviewlisttopspace"><div class="tocviewtitle"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,"tocview_0");">►</a></td><td></td><td><a href="index.html" class="tocviewlink" data-pltdoc="x"><span style="font-weight: bold">The Racket Reference</span></a></td></tr></table></div><div class="tocviewsublisttop" style="display: none;" id="tocview_0"><table cellspacing="0" cellpadding="0"><tr><td align="right">1 </td><td><a href="model.html" class="tocviewlink" data-pltdoc="x">Language Model</a></td></tr><tr><td align="right">2 </td><td><a href="notation.html" class="tocviewlink" data-pltdoc="x">Notation for Documentation</a></td></tr><tr><td align="right">3 </td><td><a href="syntax.html" class="tocviewlink" data-pltdoc="x">Syntactic Forms</a></td></tr><tr><td align="right">4 </td><td><a href="data.html" class="tocviewlink" data-pltdoc="x">Datatypes</a></td></tr><tr><td align="right">5 </td><td><a href="structures.html" class="tocviewlink" data-pltdoc="x">Structures</a></td></tr><tr><td align="right">6 </td><td><a href="mzlib_class.html" class="tocviewlink" data-pltdoc="x">Classes and Objects</a></td></tr><tr><td align="right">7 </td><td><a href="mzlib_unit.html" class="tocviewlink" data-pltdoc="x">Units</a></td></tr><tr><td align="right">8 </td><td><a href="contracts.html" class="tocviewlink" data-pltdoc="x">Contracts</a></td></tr><tr><td align="right">9 </td><td><a href="match.html" class="tocviewlink" data-pltdoc="x">Pattern Matching</a></td></tr><tr><td align="right">10 </td><td><a href="control.html" class="tocviewlink" data-pltdoc="x">Control Flow</a></td></tr><tr><td align="right">11 </td><td><a href="concurrency.html" class="tocviewlink" data-pltdoc="x">Concurrency and Parallelism</a></td></tr><tr><td align="right">12 </td><td><a href="Macros.html" class="tocviewselflink" data-pltdoc="x">Macros</a></td></tr><tr><td align="right">13 </td><td><a href="input-and-output.html" class="tocviewlink" data-pltdoc="x">Input and Output</a></td></tr><tr><td align="right">14 </td><td><a href="security.html" class="tocviewlink" data-pltdoc="x">Reflection and Security</a></td></tr><tr><td align="right">15 </td><td><a href="os.html" class="tocviewlink" data-pltdoc="x">Operating System</a></td></tr><tr><td align="right">16 </td><td><a href="memory.html" class="tocviewlink" data-pltdoc="x">Memory Management</a></td></tr><tr><td align="right">17 </td><td><a href="unsafe.html" class="tocviewlink" data-pltdoc="x">Unsafe Operations</a></td></tr><tr><td align="right">18 </td><td><a href="running.html" class="tocviewlink" data-pltdoc="x">Running Racket</a></td></tr><tr><td align="right"></td><td><a href="doc-bibliography.html" class="tocviewlink" data-pltdoc="x">Bibliography</a></td></tr><tr><td align="right"></td><td><a href="doc-index.html" class="tocviewlink" data-pltdoc="x">Index</a></td></tr></table></div></div><div class="tocviewlist"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,"tocview_1");">▼</a></td><td>12 </td><td><a href="Macros.html" class="tocviewlink" data-pltdoc="x">Macros</a></td></tr></table><div class="tocviewsublist" style="display: block;" id="tocview_1"><table cellspacing="0" cellpadding="0"><tr><td align="right">12.1 </td><td><a href="stx-patterns.html" class="tocviewlink" data-pltdoc="x">Pattern-<wbr></wbr>Based Syntax Matching</a></td></tr><tr><td align="right">12.2 </td><td><a href="stxops.html" class="tocviewlink" data-pltdoc="x">Syntax Object Content</a></td></tr><tr><td align="right">12.3 </td><td><a href="stxcmp.html" class="tocviewlink" data-pltdoc="x">Syntax Object Bindings</a></td></tr><tr><td align="right">12.4 </td><td><a href="" class="tocviewselflink" data-pltdoc="x">Syntax Transformers</a></td></tr><tr><td align="right">12.5 </td><td><a href="stxparam.html" class="tocviewlink" data-pltdoc="x">Syntax Parameters</a></td></tr><tr><td align="right">12.6 </td><td><a href="splicing.html" class="tocviewlink" data-pltdoc="x">Local Binding with Splicing Body</a></td></tr><tr><td align="right">12.7 </td><td><a href="stxprops.html" class="tocviewlink" data-pltdoc="x">Syntax Object Properties</a></td></tr><tr><td align="right">12.8 </td><td><a href="stxcerts.html" class="tocviewlink" data-pltdoc="x">Syntax Taints</a></td></tr><tr><td align="right">12.9 </td><td><a href="Expanding_Top-Level_Forms.html" class="tocviewlink" data-pltdoc="x">Expanding Top-<wbr></wbr>Level Forms</a></td></tr><tr><td align="right">12.10 </td><td><a href="include.html" class="tocviewlink" data-pltdoc="x">File Inclusion</a></td></tr><tr><td align="right">12.11 </td><td><a href="syntax-util.html" class="tocviewlink" data-pltdoc="x">Syntax Utilities</a></td></tr></table></div></div><div class="tocviewlist"><table cellspacing="0" cellpadding="0"><tr><td style="width: 1em;"><a href="javascript:void(0);" title="Expand/Collapse" class="tocviewtoggle" onclick="TocviewToggle(this,"tocview_2");">►</a></td><td>12.4 </td><td><a href="" class="tocviewselflink" data-pltdoc="x">Syntax Transformers</a></td></tr></table><div class="tocviewsublistbottom" style="display: none;" id="tocview_2"><table cellspacing="0" cellpadding="0"><tr><td align="right">12.4.1 </td><td><a href="#%28part._require-trans%29" class="tocviewlink" data-pltdoc="x"><span class="RktSym"><span class="RktStxLink">require</span></span> Transformers</a></td></tr><tr><td align="right">12.4.2 </td><td><a href="#%28part._provide-trans%29" class="tocviewlink" data-pltdoc="x"><span class="RktSym"><span class="RktStxLink">provide</span></span> Transformers</a></td></tr><tr><td align="right">12.4.3 </td><td><a href="#%28part._keyword-trans%29" class="tocviewlink" data-pltdoc="x">Keyword-<wbr></wbr>Argument Conversion Introspection</a></td></tr></table></div></div></div><div class="tocsub"><div class="tocsubtitle">On this page:</div><table class="tocsublist" cellspacing="0"><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">set!-<wbr></wbr>transformer?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>set!-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer-procedure%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">set!-<wbr></wbr>transformer-<wbr></wbr>procedure</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>set!-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">rename-<wbr></wbr>transformer?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>rename-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer-target%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">rename-<wbr></wbr>transformer-<wbr></wbr>target</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>rename-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">local-<wbr></wbr>expand</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-expand-expression%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>expand-<wbr></wbr>expression</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._local-transformer-expand%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">local-<wbr></wbr>transformer-<wbr></wbr>expand</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%2Fcapture-lifts%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">local-<wbr></wbr>expand/<span class="mywbr"> </span>capture-<wbr></wbr>lifts</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._local-transformer-expand%2Fcapture-lifts%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">local-<wbr></wbr>transformer-<wbr></wbr>expand/<span class="mywbr"> </span>capture-<wbr></wbr>lifts</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">internal-<wbr></wbr>definition-<wbr></wbr>context?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-definition-context%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>make-<wbr></wbr>definition-<wbr></wbr>context</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-bind-syntaxes%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>bind-<wbr></wbr>syntaxes</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-introduce%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">internal-<wbr></wbr>definition-<wbr></wbr>context-<wbr></wbr>introduce</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-seal%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">internal-<wbr></wbr>definition-<wbr></wbr>context-<wbr></wbr>seal</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._identifier-remove-from-definition-context%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">identifier-<wbr></wbr>remove-<wbr></wbr>from-<wbr></wbr>definition-<wbr></wbr>context</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aexpansion-contexts%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>expansion-<wbr></wbr>contexts</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>value</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%2Fimmediate%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>value/<span class="mywbr"> </span>immediate</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>expression</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-values-expression%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>values-<wbr></wbr>expression</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-context%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>context</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>module</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module-end-declaration%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>module-<wbr></wbr>end-<wbr></wbr>declaration</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-require%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>require</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-provide%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>lift-<wbr></wbr>provide</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-name%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>name</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>context</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>phase-<wbr></wbr>level</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-exports%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>module-<wbr></wbr>exports</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-submodules%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>submodules</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-get-shadower%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>get-<wbr></wbr>shadower</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-delta-introducer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>make-<wbr></wbr>delta-<wbr></wbr>introducer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._syntax-local-certifier%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>certifier</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>transforming?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming-module-expression~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>transforming-<wbr></wbr>module-<wbr></wbr>expression?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-identifier-as-binding%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>identifier-<wbr></wbr>as-<wbr></wbr>binding</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-introduce%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>introduce</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-introducer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>syntax-<wbr></wbr>introducer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-delta-introducer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>syntax-<wbr></wbr>delta-<wbr></wbr>introducer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-transforming-module-provides~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>transforming-<wbr></wbr>module-<wbr></wbr>provides?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-defined-identifiers%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>module-<wbr></wbr>defined-<wbr></wbr>identifiers</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-required-identifiers%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>module-<wbr></wbr>required-<wbr></wbr>identifiers</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aliberal-define-context%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>liberal-<wbr></wbr>define-<wbr></wbr>context</span></span></a></td></tr><tr><td><a href="#%28def._%28%28quote._~23~25kernel%29._liberal-define-context~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">liberal-<wbr></wbr>define-<wbr></wbr>context?</span></span></a></td></tr><tr><td><span class="tocsublinknumber">12.4.1<tt> </tt></span><a href="#%28part._require-trans%29" class="tocsubseclink" data-pltdoc="x"><span class="RktSym"><span class="RktStxLink">require</span></span> Transformers</a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._expand-import%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">expand-<wbr></wbr>import</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._make-require-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>require-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._prop~3arequire-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>require-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._require-transformer~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">require-<wbr></wbr>transformer?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">import</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import-source%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">import-<wbr></wbr>source</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">current-<wbr></wbr>require-<wbr></wbr>module-<wbr></wbr>path</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._convert-relative-module-path%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">convert-<wbr></wbr>relative-<wbr></wbr>module-<wbr></wbr>path</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._syntax-local-require-certifier%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>require-<wbr></wbr>certifier</span></span></a></td></tr><tr><td><span class="tocsublinknumber">12.4.2<tt> </tt></span><a href="#%28part._provide-trans%29" class="tocsubseclink" data-pltdoc="x"><span class="RktSym"><span class="RktStxLink">provide</span></span> Transformers</a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._expand-export%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">expand-<wbr></wbr>export</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._pre-expand-export%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">pre-<wbr></wbr>expand-<wbr></wbr>export</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>provide-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-pre-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">make-<wbr></wbr>provide-<wbr></wbr>pre-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>provide-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-pre-transformer%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">prop:<span class="mywbr"> </span>provide-<wbr></wbr>pre-<wbr></wbr>transformer</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-transformer~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">provide-<wbr></wbr>transformer?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-pre-transformer~3f%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">provide-<wbr></wbr>pre-<wbr></wbr>transformer?</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">export</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._syntax-local-provide-certifier%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>local-<wbr></wbr>provide-<wbr></wbr>certifier</span></span></a></td></tr><tr><td><span class="tocsublinknumber">12.4.3<tt> </tt></span><a href="#%28part._keyword-trans%29" class="tocsubseclink" data-pltdoc="x">Keyword-<wbr></wbr>Argument Conversion Introspection</a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fkeyword-transform..rkt%29._syntax-procedure-alias-property%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>procedure-<wbr></wbr>alias-<wbr></wbr>property</span></span></a></td></tr><tr><td><a href="#%28def._%28%28lib._racket%2Fkeyword-transform..rkt%29._syntax-procedure-converted-arguments-property%29%29" class="tocsubnonseclink" data-pltdoc="x"><span class="RktSym"><span class="RktValLink">syntax-<wbr></wbr>procedure-<wbr></wbr>converted-<wbr></wbr>arguments-<wbr></wbr>property</span></span></a></td></tr></table></div></div><div class="maincolumn"><div class="main"><div class="navsettop"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, "6.3", "../");" onfocus="this.style.color="black"; this.style.textAlign="left"; if (this.value == "...search manuals...") this.value="";" onblur="if (this.value.match(/^ *$/)) { this.style.color="#888"; this.style.textAlign="center"; this.value="...search manuals..."; }"/></form> <a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot("6.3");">top</a></span><span class="navright"> <a href="stxcmp.html" title="backward to "12.3 Syntax Object Bindings"" data-pltdoc="x">← prev</a> <a href="Macros.html" title="up to "12 Macros"" data-pltdoc="x">up</a> <a href="stxparam.html" title="forward to "12.5 Syntax Parameters"" data-pltdoc="x">next →</a></span> </div><h4 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""stxtrans"">12.4<tt> </tt><a name="(part._stxtrans)"></a>Syntax Transformers</h4><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._set!-transformer~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">set!-transformer?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> is a value created by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValLink" data-pltdoc="x">make-set!-transformer</a></span> or an instance of a structure type with
the <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:set!-transformer</a></span> property, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._make-set!-transformer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-set!-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">proc</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">set!-transformer?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">proc</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Creates an <a href="syntax-model.html#%28tech._assignment._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">assignment transformer</span></a> that cooperates with
<span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>. If the result of <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValLink" data-pltdoc="x">make-set!-transformer</a></span> is
bound to <span class="RktVar">id</span> as a <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding, then
<span class="RktVar">proc</span> is applied as a transformer when <span class="RktVar">id</span> is
used in an expression position, or when it is used as the target of a
<span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span> assignment as <span class="RktPn">(</span><span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span><span class="stt"> </span><span class="RktVar">id</span><span class="stt"> </span><span class="RktVar">expr</span><span class="RktPn">)</span>. When the
identifier appears as a <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span> target, the entire <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>
expression is provided to the transformer.</div></p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Example:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._let%29%29" class="RktStxLink" data-pltdoc="x">let</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktVal">1</span><span class="RktPn">]</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktSym">y</span><span class="hspace"> </span><span class="RktVal">2</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._let-syntax%29%29" class="RktStxLink" data-pltdoc="x">let-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValLink" data-pltdoc="x">make-set!-transformer</a></span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29._syntax-case%29%29" class="RktStxLink" data-pltdoc="x">syntax-case</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">Redirect mutation of x to y</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktPn">(</span><span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span><span class="hspace"> </span><span class="RktSym">id</span><span class="hspace"> </span><span class="RktSym">v</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span><span class="hspace"> </span><span class="RktSym">y</span><span class="hspace"> </span><span class="RktSym">v</span><span class="RktPn">)</span><span class="RktPn">]</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">Normal use of </span><span class="RktSym">x</span><span class="RktCmt"> really gets </span><span class="RktSym">x</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktSym">id</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">id</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">x</span><span class="RktPn">]</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktVal">3</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list%29%29" class="RktValLink" data-pltdoc="x">list</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktSym">y</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><p><span class="RktRes">'(1 3)</span></p></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._set!-transformer-procedure))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer-procedure%29%29" class="RktValDef RktValLink" data-pltdoc="x">set!-transformer-procedure</a></span></span><span class="hspace"> </span><span class="RktVar">transformer</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">transformer</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">set!-transformer?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns the procedure that was passed to
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValLink" data-pltdoc="x">make-set!-transformer</a></span> to create <span class="RktVar">transformer</span> or that
is identified by the <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:set!-transformer</a></span> property of
<span class="RktVar">transformer</span>.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((quote._~23~25kernel)._prop~3aset!-transformer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:set!-transformer</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A <a href="structprops.html#%28tech._structure._type._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">structure type property</span></a> to identify structure types that act
as <a href="syntax-model.html#%28tech._assignment._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">assignment transformers</span></a> like the ones created by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-set%21-transformer%29%29" class="RktValLink" data-pltdoc="x">make-set!-transformer</a></span>.</div></p><p>The property value must be an exact integer or procedure of one or two
arguments. In the former case, the integer designates a field within
the structure that should contain a procedure; the integer must be
between <span class="RktVal">0</span> (inclusive) and the number of non-automatic fields
in the structure type (exclusive, not counting supertype fields), and
the designated field must also be specified as immutable.</p><p>If the property value is a procedure of one argument, then the
procedure serves as a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> and for <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>
transformations. If the property value is a procedure of two
arguments, then the first argument is the structure whose type has
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:set!-transformer</a></span> property, and the second argument is a
syntax object as for a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> and for <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>
transformations; <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._set%21-transformer-procedure%29%29" class="RktValLink" data-pltdoc="x">set!-transformer-procedure</a></span> applied to the
structure produces a new function that accepts just the syntax object
and calls the procedure associated through the property. Finally, if the
property value is an integer, the target identifier is extracted from
the structure instance; if the field value is not a procedure of one
argument, then a procedure that always calls
<span class="RktSym"><a href="exns.html#%28def._%28%28quote._~23~25kernel%29._raise-syntax-error%29%29" class="RktValLink" data-pltdoc="x">raise-syntax-error</a></span> is used, instead.</p><p>If a value has both the <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:set!-transformer</a></span> and
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:rename-transformer</a></span> properties, then the latter takes
precedence. If a structure type has the <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aset%21-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:set!-transformer</a></span>
and <span class="RktSym"><a href="procedures.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._prop~3aprocedure%29%29" class="RktValLink" data-pltdoc="x">prop:procedure</a></span> properties, then the former takes
precedence for the purposes of macro expansion.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._rename-transformer~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">rename-transformer?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> is a value created by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span> or an instance of a structure type
with the <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:rename-transformer</a></span> property, <span class="RktVal">#f</span>
otherwise.</div></p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">rename-transformer?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym"><a href="values.html#%28def._%28%28quote._~23~25kernel%29._values%29%29" class="RktValLink" data-pltdoc="x">values</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">rename-transformer?</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">not-a-rename-transformer</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#f</span></p></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._make-rename-transformer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-rename-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">rename-transformer?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Creates a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a> that, when used as a
<a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding, acts as a transformer that inserts the
identifier <span class="RktVar">id-stx</span> in place of whatever identifier binds the
transformer, including in non-application positions, in <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>
expressions.</div></p><p>Such a transformer could be written manually, but the one created by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span> triggers special cooperation with the
parser and other syntactic forms when <span class="RktVar">id</span> is bound to the
rename transformer:</p><ul><li><p>The parser installs a <span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._free-identifier~3d~3f%29%29" class="RktValLink" data-pltdoc="x">free-identifier=?</a></span> and
<span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._identifier-binding%29%29" class="RktValLink" data-pltdoc="x">identifier-binding</a></span> equivalence between <span class="RktVar">id</span>
and <span class="RktVar">id-stx</span>, as long as <span class="RktVar">id-stx</span> does not have
a true value for the <a name="(idx._(gentag._180._(lib._scribblings/reference/reference..scrbl)))"></a><span class="RktVal">'</span><span class="RktVal">not-free-identifier=?</span>
<a href="stxprops.html#%28tech._syntax._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax property</span></a>.</p></li><li><p>A <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> of <span class="RktVar">id</span> provides the binding
indicated by <span class="RktVar">id-stx</span> instead of <span class="RktVar">id</span>, as long
as <span class="RktVar">id-stx</span> does not have a true value for the
<a name="(idx._(gentag._181._(lib._scribblings/reference/reference..scrbl)))"></a><span class="RktVal">'</span><span class="RktVal">not-free-identifier=?</span> <a href="stxprops.html#%28tech._syntax._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax property</span></a>
and as long as <span class="RktVar">id-stx</span> has a binding.</p></li><li><p>If <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> exports <span class="RktVar">id</span>, it uses a
symbol-valued <a name="(idx._(gentag._182._(lib._scribblings/reference/reference..scrbl)))"></a><span class="RktVal">'</span><span class="RktVal">nominal-id</span> property of
<span class="RktVar">id-stx</span> to specify the “nominal source identifier” of
the binding as reported by <span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._identifier-binding%29%29" class="RktValLink" data-pltdoc="x">identifier-binding</a></span>.</p></li><li><p>If <span class="RktVar">id-stx</span> has a true value for the
<a name="(idx._(gentag._183._(lib._scribblings/reference/reference..scrbl)))"></a><span class="RktVal">'</span><span class="RktVal">not-provide-all-defined</span> <a href="stxprops.html#%28tech._syntax._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax
property</span></a>, then <span class="RktVar">id</span> (or its target) is not exported by
<span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._all-defined-out%29%29" class="RktStxLink" data-pltdoc="x">all-defined-out</a></span>.</p></li><li><p>The <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span> function recognizes
rename-transformer bindings and consult their targets.</p></li></ul><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">my-or</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym"><a href="if.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._or%29%29" class="RktStxLink" data-pltdoc="x">or</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">my-or</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktVal">#t</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._free-identifier~3d~3f%29%29" class="RktValLink" data-pltdoc="x">free-identifier=?</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">my-or</span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym"><a href="if.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._or%29%29" class="RktStxLink" data-pltdoc="x">or</a></span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#t</span></p></td></tr></table></blockquote></td></tr></table></p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: Removed an optional second argument.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._rename-transformer-target))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer-target%29%29" class="RktValDef RktValLink" data-pltdoc="x">rename-transformer-target</a></span></span><span class="hspace"> </span><span class="RktVar">transformer</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">transformer</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">rename-transformer?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns the identifier passed to <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span> to
create <span class="RktVar">transformer</span> or as indicated by a
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:rename-transformer</a></span> property on <span class="RktVar">transformer</span>.</div></p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Example:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._rename-transformer-target%29%29" class="RktValLink" data-pltdoc="x">rename-transformer-target</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym"><a href="if.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._or%29%29" class="RktStxLink" data-pltdoc="x">or</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">#<syntax:8:0 or></span></p></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((quote._~23~25kernel)._prop~3arename-transformer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:rename-transformer</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A <a href="structprops.html#%28tech._structure._type._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">structure type property</span></a> to identify structure types that act
as <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformers</span></a> like the ones created by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span>.</div></p><p>The property value must be an exact integer, an identifier
<a href="syntax-model.html#%28tech._syntax._object%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax object</span></a>, or a procedure that takes one argument.
In the former case, the integer designates a
field within the structure that should contain an identifier; the
integer must be between <span class="RktVal">0</span> (inclusive) and the number of
non-automatic fields in the structure type (exclusive, not counting
supertype fields), and the designated field must also be specified as
immutable.</p><p>If the property value is an identifier, the identifier serves as the
target for renaming, just like the first argument to
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span>. If the property value is an integer,
the target identifier is extracted from the structure instance; if the
field value is not an identifier, then an identifier <span class="RktSym">?</span>
with an empty context is used, instead.</p><p>If the property value is a procedure that takes one argument, then the procedure
is called to obtain the identifier that the rename transformer will use
as a target identifier. If the procedure returns any value that is not
an identifier, the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">Example of a procedure argument for prop:rename-transformer</span></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">slv-1</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">first-transformer-binding</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">slv-2</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">second-transformer-binding</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="define-struct.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._struct%29%29" class="RktStxLink" data-pltdoc="x">struct</a></span><span class="hspace"> </span><span class="RktSym">slv-cooperator</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">redirect-to-first?</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">#:property</span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:rename-transformer</a></span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~ce~bb%29%29" class="RktStxLink" data-pltdoc="x">λ</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">inst</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="if.html#%28form._%28%28quote._~23~25kernel%29._if%29%29" class="RktStxLink" data-pltdoc="x">if</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">slv-cooperator-redirect-to-first?</span><span class="hspace"> </span><span class="RktSym">inst</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">slv-1</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">slv-2</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">slv-lookup</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29._syntax-case%29%29" class="RktStxLink" data-pltdoc="x">syntax-case</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29.__%29%29" class="RktStxLink" data-pltdoc="x">_</a></span><span class="hspace"> </span><span class="RktSym">id</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#`</span><span class="RktVal">'</span><span class="RktVal">#,</span><span class="RktVal">(</span><span class="RktVal">syntax-local-value</span><span class="hspace"> </span><span class="RktVal">#'</span><span class="RktVal">id</span><span class="RktVal">)</span><span class="RktPn">]</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">slv-inst-1</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">slv-cooperator</span><span class="hspace"> </span><span class="RktVal">#t</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">slv-inst-2</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">slv-cooperator</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">slv-lookup</span><span class="hspace"> </span><span class="RktSym">slv-inst-1</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'first-transformer-binding</span></p></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">slv-lookup</span><span class="hspace"> </span><span class="RktSym">slv-inst-2</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'second-transformer-binding</span></p></td></tr></table></blockquote></td></tr></table></p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: the property now accepts a procedure of one argument.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._local-expand))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValDef RktValLink" data-pltdoc="x">local-expand</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">context-v</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stop-ids</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">intdef-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">context-v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">top-level</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module-begin</span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stop-ids</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._pair~3f%29%29" class="RktValLink" data-pltdoc="x">pair?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">=</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVal">#f</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Expands <span class="RktVar">stx</span> in the lexical context of the expression
currently being expanded. The <span class="RktVar">context-v</span> argument is used as
the result of <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-context</a></span> for immediate expansions;
a list indicates an <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a>, and more
information on the form of the list is below. If <span class="RktVar">stx</span> is not
already a <a href="syntax-model.html#%28tech._syntax._object%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax object</span></a>, it is coerced with
<span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._datum-~3esyntax%29%29" class="RktValLink" data-pltdoc="x">datum->syntax</a></span><span class="stt"> </span><span class="RktVal">#f</span><span class="stt"> </span><span class="RktVar">stx</span><span class="RktPn">)</span> before expansion.</div></p><p>When an identifier in <span class="RktVar">stop-ids</span> is encountered by the expander
in a sub-expression, expansions stops for the sub-expression. If
<span class="RktVar">stop-ids</span> is a non-empty list and does not contain just <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span>, then
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span>, <span class="RktSym"><a href="quote.html#%28form._%28%28quote._~23~25kernel%29._quote%29%29" class="RktStxLink" data-pltdoc="x">quote</a></span>, <span class="RktSym"><a href="set_.html#%28form._%28%28quote._~23~25kernel%29._set%21%29%29" class="RktStxLink" data-pltdoc="x">set!</a></span>, <span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span>,
<span class="RktSym"><a href="lambda.html#%28form._%28%28quote._~23~25kernel%29._case-lambda%29%29" class="RktStxLink" data-pltdoc="x">case-lambda</a></span>, <span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._let-values%29%29" class="RktStxLink" data-pltdoc="x">let-values</a></span>, <span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._letrec-values%29%29" class="RktStxLink" data-pltdoc="x">letrec-values</a></span>,
<span class="RktSym"><a href="if.html#%28form._%28%28quote._~23~25kernel%29._if%29%29" class="RktStxLink" data-pltdoc="x">if</a></span>, <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin0%29%29" class="RktStxLink" data-pltdoc="x">begin0</a></span>, <span class="RktSym"><a href="wcm.html#%28form._%28%28quote._~23~25kernel%29._with-continuation-mark%29%29" class="RktStxLink" data-pltdoc="x">with-continuation-mark</a></span>,
<span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._letrec-syntaxes%2Bvalues%29%29" class="RktStxLink" data-pltdoc="x">letrec-syntaxes+values</a></span>, <span class="RktSym"><a href="application.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25app%29%29" class="RktStxLink" data-pltdoc="x">#%app</a></span>,
<span class="RktSym"><a href="__expression.html#%28form._%28%28quote._~23~25kernel%29._~23~25expression%29%29" class="RktStxLink" data-pltdoc="x">#%expression</a></span>, <span class="RktSym"><a href="__top.html#%28form._%28%28quote._~23~25kernel%29._~23~25top%29%29" class="RktStxLink" data-pltdoc="x">#%top</a></span>, and
<span class="RktSym"><a href="Locations____variable-reference.html#%28form._%28%28quote._~23~25kernel%29._~23~25variable-reference%29%29" class="RktStxLink" data-pltdoc="x">#%variable-reference</a></span> are added to <span class="RktVar">stop-ids</span>. If
<span class="RktSym"><a href="application.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25app%29%29" class="RktStxLink" data-pltdoc="x">#%app</a></span> or <span class="RktSym"><a href="quote.html#%28form._%28%28quote._~23~25kernel%29._~23~25datum%29%29" class="RktStxLink" data-pltdoc="x">#%datum</a></span> appears in
<span class="RktVar">stop-ids</span>, then application and
literal data expressions without the respective explicit form are not
wrapped with the explicit form, and <span class="RktSym"><a href="__top.html#%28form._%28%28quote._~23~25kernel%29._~23~25top%29%29" class="RktStxLink" data-pltdoc="x">#%top</a></span> wrappers are
never added (even with an empty <span class="RktVar">stop-ids</span> list). If <span class="RktVar">stop-ids</span> is <span class="RktVal">#f</span>
instead of a list, then <span class="RktVar">stx</span> is expanded only as long as the
outermost form of <span class="RktVar">stx</span> is a macro (i.e., expansion does not
proceed to sub-expressions). A fully expanded form can include the
bindings listed in <a href="syntax-model.html#%28part._fully-expanded%29" data-pltdoc="x">Fully Expanded Programs</a> plus the
<span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._letrec-syntaxes%2Bvalues%29%29" class="RktStxLink" data-pltdoc="x">letrec-syntaxes+values</a></span> form and <span class="RktSym"><a href="__expression.html#%28form._%28%28quote._~23~25kernel%29._~23~25expression%29%29" class="RktStxLink" data-pltdoc="x">#%expression</a></span>
in any expression position.</p><p>When <span class="RktSym"><a href="module.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25plain-module-begin%29%29" class="RktStxLink" data-pltdoc="x">#%plain-module-begin</a></span> is not itself in <span class="RktVar">stop-ids</span>
and <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span> is in <span class="RktVar">stop-ids</span>, then the
<span class="RktSym"><a href="module.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25plain-module-begin%29%29" class="RktStxLink" data-pltdoc="x">#%plain-module-begin</a></span> transformer refrains from expanding
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span> sub-forms. Otherwise, the
<span class="RktSym"><a href="module.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25plain-module-begin%29%29" class="RktStxLink" data-pltdoc="x">#%plain-module-begin</a></span> transformer detects and expands sub-forms
(such as <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span>) independent of the corresponding
identifier’s presence in <span class="RktVar">stop-ids</span>.</p><p>When <span class="RktVar">context-v</span> is <span class="RktVal">'</span><span class="RktVal">module-begin</span>, and the result of
expansion is a <span class="RktSym"><a href="module.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~23~25plain-module-begin%29%29" class="RktStxLink" data-pltdoc="x">#%plain-module-begin</a></span> form, then a
<span class="RktVal">'</span><span class="RktVal">submodule</span> <a href="stxprops.html#%28tech._syntax._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax property</span></a> is added to each enclosed
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form (but not <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span> forms) in the same way as by
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> expansion.</p><p>The optional <span class="RktVar">intdef-ctx</span> argument must be either <span class="RktVal">#f</span>,
the result of <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-definition-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-make-definition-context</a></span>, or a list
of such results. In the latter two cases, lexical information for
internal definitions is added to <span class="RktVar">stx</span> before it is expanded
(in reverse order relative to the list). The lexical information is
also added to the expansion result (because the expansion might
introduce bindings or references to internal-definition bindings).</p><p>For a particular <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a>, generate a unique
value and put it into a list for <span class="RktVar">context-v</span>. To allow
<a href="#%28tech._liberal._expansion%29" class="techoutside" data-pltdoc="x"><span class="techinside">liberal expansion</span></a> of <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span> forms, the generated value
should be an instance of a structure with a true value for
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aliberal-define-context%29%29" class="RktValLink" data-pltdoc="x">prop:liberal-define-context</a></span>. If the internal-definition
context is meant to be self-contained, the list for <span class="RktVar">context-v</span>
should contain only the generated value; if the internal-definition
context is meant to splice into an immediately enclosing context, then
when <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-context</a></span> produces a list, <span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._cons%29%29" class="RktValLink" data-pltdoc="x">cons</a></span> the
generated value onto that list.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fmisc..rkt%29._define-syntax-rule%29%29" class="RktStxLink" data-pltdoc="x">define-syntax-rule</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">do-print</span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29._......%29%29" class="RktStxLink" data-pltdoc="x">...</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="hspace"> </span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29._......%29%29" class="RktStxLink" data-pltdoc="x">...</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fmisc..rkt%29._define-syntax-rule%29%29" class="RktStxLink" data-pltdoc="x">define-syntax-rule</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">hello</span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">do-print</span><span class="hspace"> </span><span class="RktVal">"hello ~a"</span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">show</span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29._syntax-case%29%29" class="RktStxLink" data-pltdoc="x">syntax-case</a></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktPn">(</span><span class="RktSym"><a href="stx-patterns.html#%28form._%28%28lib._racket%2Fprivate%2Fstxcase-scheme..rkt%29.__%29%29" class="RktStxLink" data-pltdoc="x">_</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._let%29%29" class="RktStxLink" data-pltdoc="x">let</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">partly</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym">hello</span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list%29%29" class="RktValLink" data-pltdoc="x">list</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">do-print</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">]</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">[</span><span class="RktSym">fully</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym">hello</span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktVal">"partly expanded: ~s\n"</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-~3edatum%29%29" class="RktValLink" data-pltdoc="x">syntax->datum</a></span><span class="hspace"> </span><span class="RktSym">partly</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktVal">"fully expanded: ~s\n"</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-~3edatum%29%29" class="RktValLink" data-pltdoc="x">syntax->datum</a></span><span class="hspace"> </span><span class="RktSym">fully</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktSym">fully</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">show</span><span class="hspace"> </span><span class="RktVal">1</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td><p><span class="RktOut">partly expanded: (do-print "hello ~a" 1)</span></p></td></tr><tr><td><p><span class="RktOut">fully expanded: (printf "hello ~a" 1)</span></p></td></tr><tr><td><p><span class="RktOut">hello 1</span></p></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr></table></blockquote></td></tr></table></p><p class="SHistory">Changed in version 6.0.1.3 of package <span class="stt">base</span>: Changed treatment of <span class="RktSym"><a href="__top.html#%28form._%28%28quote._~23~25kernel%29._~23~25top%29%29" class="RktStxLink" data-pltdoc="x">#%top</a></span>
so that it is never introduced as
an explicit wrapper.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-expand-expression))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-expand-expression%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-expand-expression</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0"><tr><td><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td><td><span class="hspace"> </span></td><td><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span> given <span class="RktVal">'</span><span class="RktVal">expression</span> and an empty
stop list, but with two results: a syntax object for the fully
expanded expression, and a syntax object whose content is opaque. The
latter can be used in place of the former (perhaps in a larger
expression produced by a macro transformer), and when the macro
expander encounters the opaque object, it substitutes the fully
expanded expression without re-expanding it; the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3asyntax%29%29" class="RktValLink" data-pltdoc="x">exn:fail:syntax</a></span> exception is raised if the expansion context includes
<a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> that were not present for the original expansion, in which
case re-expansion might produce different results. Consistent use of
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-expand-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-expand-expression</a></span> and the opaque object thus
avoids quadratic expansion times when local expansions are nested.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._local-transformer-expand))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-transformer-expand%29%29" class="RktValDef RktValLink" data-pltdoc="x">local-transformer-expand</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">context-v</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stop-ids</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">intdef-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">context-v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">top-level</span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stop-ids</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span>, but <span class="RktVar">stx</span> is expanded as a
transformer expression instead of a run-time expression.
For <span class="RktVal">'</span><span class="RktVal">expression</span> expansion, any
lifted expressions—<wbr></wbr>from calls to
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span> during the expansion of
<span class="RktVar">stx</span>—<wbr></wbr>are captured into a <span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._let-values%29%29" class="RktStxLink" data-pltdoc="x">let-values</a></span> form in the
result.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._local-expand/capture-lifts))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%2Fcapture-lifts%29%29" class="RktValDef RktValLink" data-pltdoc="x">local-expand/capture-lifts</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">context-v</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stop-ids</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">lift-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">context-v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">top-level</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module-begin</span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stop-ids</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">lift-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._gensym%29%29" class="RktValLink" data-pltdoc="x">gensym</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">lifts</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span>, but the result is a syntax object that
represents a <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span> expression. Lifted expressions—<wbr></wbr>from
calls to <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span> during the expansion of
<span class="RktVar">stx</span>—<wbr></wbr>appear with their identifiers in <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span>
forms, and the expansion of <span class="RktVar">stx</span> is the last expression in the
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span>. The <span class="RktVar">lift-ctx</span> value is reported by
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-context</a></span> during local expansion. The lifted
expressions are not expanded, but instead left as provided in the
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span> form.</div></p><p>If <span class="RktVar">context-v</span> is <span class="RktVal">'</span><span class="RktVal">top-level</span> or <span class="RktVal">'</span><span class="RktVal">module</span>, then
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> forms can appear in the result as added via
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-module</a></span>. If <span class="RktVar">context-v</span> is
<span class="RktVal">'</span><span class="RktVal">module</span>, then <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span> forms can appear, too.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._local-transformer-expand/capture-lifts))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-transformer-expand%2Fcapture-lifts%29%29" class="RktValDef RktValLink" data-pltdoc="x">local-transformer-expand/capture-lifts</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">context-v</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stop-ids</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">lift-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">context-v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">top-level</span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stop-ids</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">lift-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._gensym%29%29" class="RktValLink" data-pltdoc="x">gensym</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">lifts</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%2Fcapture-lifts%29%29" class="RktValLink" data-pltdoc="x">local-expand/capture-lifts</a></span>, but <span class="RktVar">stx</span> is expanded
as a transformer expression instead of a run-time expression. Lifted
expressions are reported as <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span> forms (in the
transformer environment).</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._internal-definition-context~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">internal-definition-context?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> is an <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition
context</span></a>, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-make-definition-context))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-definition-context%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-make-definition-context</a></span></span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">add-scope?</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">add-scope?</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr></table></blockquote></div><div class="SIntrapara">Creates an opaque <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a> value to be used
with <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span> and other functions. A transformer should
create one context for each set of internal definitions to be
expanded, and use it when expanding any form whose lexical context
should include the definitions. After discovering an internal
<span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span> or <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-syntaxes%29%29" class="RktStxLink" data-pltdoc="x">define-syntaxes</a></span> form, use
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-bind-syntaxes%29%29" class="RktValLink" data-pltdoc="x">syntax-local-bind-syntaxes</a></span> to add bindings to the context.</div></p><p>An <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a> internally creates a
<a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> to represent the context. Unless <span class="RktVar">add-scope?</span> is
<span class="RktVal">#f</span>, the <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> is added to any form that is expanded
within the context or that appears as the result of a (partial)
expansion within the context.</p><p>If <span class="RktVar">intdef-ctx</span> is not <span class="RktVal">#f</span>, then the new
internal-definition context extends the given one. An extending
definition context adds all <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> that are added by
<span class="RktVar">intdef-ctx</span>, and expanding in the new internal-definition context
can use bindings previously introduced into <span class="RktVar">intdef-ctx</span>.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: Added the <span class="RktVar">add-scope?</span> argument,
and made calling
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-seal%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context-seal</a></span>
no longer necessary.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-bind-syntaxes))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-bind-syntaxes%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-bind-syntaxes</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">id-list</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">expr</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-list</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">expr</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Binds each identifier in <span class="RktVar">id-list</span> within the
<a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a> represented by <span class="RktVar">intdef-ctx</span>, where
<span class="RktVar">intdef-ctx</span> is the result of
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-definition-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-make-definition-context</a></span>. Supply <span class="RktVal">#f</span> for
<span class="RktVar">expr</span> when the identifiers correspond to
<span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span> bindings, and supply a compile-time expression
when the identifiers correspond to <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-syntaxes%29%29" class="RktStxLink" data-pltdoc="x">define-syntaxes</a></span> bindings;
in the latter case, the number of values produced by the expression should
match the number of identifiers, otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract~3aarity%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract:arity</a></span> exception is raised.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._internal-definition-context-introduce))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-introduce%29%29" class="RktValDef RktValLink" data-pltdoc="x">internal-definition-context-introduce</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">mode</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">flip</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">add</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">remove</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">flip</span></td></tr></table></blockquote></div><div class="SIntrapara">Flips, adds, or removes (depending on <span class="RktVar">mode</span>) the <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a>
for <span class="RktVar">intdef-ctx</span> for all parts of <span class="RktVar">stx</span>.</div></p><p class="SHistory">Added in version 6.3 of package <span class="stt">base</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._internal-definition-context-seal))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-seal%29%29" class="RktValDef RktValLink" data-pltdoc="x">internal-definition-context-seal</a></span></span><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">intdef-ctx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">For backward compatibility only; has no effect.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._identifier-remove-from-definition-context))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._identifier-remove-from-definition-context%29%29" class="RktValDef RktValLink" data-pltdoc="x">identifier-remove-from-definition-context</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">id-stx</span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Removes all of the <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> of <span class="RktVar">intdef-ctx</span> (or of each
element in a list <span class="RktVar">intdef-ctx</span>) from <span class="RktVar">id-stx</span>.</div></p><p>The <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._identifier-remove-from-definition-context%29%29" class="RktValLink" data-pltdoc="x">identifier-remove-from-definition-context</a></span> function is
provided for backward compatibility; the more general
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context-introduce%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context-introduce</a></span> function is preferred.</p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: Simplified the operation to <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> removal.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((quote._~23~25kernel)._prop~3aexpansion-contexts))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aexpansion-contexts%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:expansion-contexts</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A <a href="structprops.html#%28tech._structure._type._property%29" class="techoutside" data-pltdoc="x"><span class="techinside">structure type property</span></a> to constrain the use of macro
<a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformers</span></a> and <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformers</span></a>. The property’s
value must be a list of symbols, where the allowed symbols are
<span class="RktVal">'</span><span class="RktVal">expression</span>, <span class="RktVal">'</span><span class="RktVal">top-level</span>, <span class="RktVal">'</span><span class="RktVal">module</span>,
<span class="RktVal">'</span><span class="RktVal">module-begin</span>, and <span class="RktVal">'</span><span class="RktVal">definition-context</span>. Each symbol
corresponds to an expansion context in the same way as for
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span> or as reported by <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-context</a></span>,
except that <span class="RktVal">'</span><span class="RktVal">definition-context</span> is used (instead of a list)
to represent an <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a>.</div></p><p><div class="SIntrapara">If an identifier is bound to a transformer whose list does not include
a symbol for a particular use of the identifier, then the use is
adjusted as follows:
</div><div class="SIntrapara"><ul><li><p>In a <span class="RktVal">'</span><span class="RktVal">module-begin</span> context, then the use is wrapped in
a <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin%29%29" class="RktStxLink" data-pltdoc="x">begin</a></span> form.</p></li><li><p>In a <span class="RktVal">'</span><span class="RktVal">module</span>, <span class="RktVal">'</span><span class="RktVal">top-level</span>,
<span class="RktVal">'</span><span class="RktVal">internal-definition</span> or context, if
<span class="RktVal">'</span><span class="RktVal">expression</span> is present in the list, then the use is
wrapped in an <span class="RktSym"><a href="__expression.html#%28form._%28%28quote._~23~25kernel%29._~23~25expression%29%29" class="RktStxLink" data-pltdoc="x">#%expression</a></span> form.</p></li><li><p>Otherwise, a syntax error is reported.</p></li></ul></div></p><p>The <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aexpansion-contexts%29%29" class="RktValLink" data-pltdoc="x">prop:expansion-contexts</a></span> property is most useful in
combination with <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3arename-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:rename-transformer</a></span>, since a general
<a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> procedure can use <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-context</a></span>.
Furthermore, a <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aexpansion-contexts%29%29" class="RktValLink" data-pltdoc="x">prop:expansion-contexts</a></span> property makes the
most sense when a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a>’s identifier has the
<span class="RktVal">'</span><span class="RktVal">not-free-identifier=?</span> property, otherwise a definition of
the binding creates a binding alias that effectively routes around the
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aexpansion-contexts%29%29" class="RktValLink" data-pltdoc="x">prop:expansion-contexts</a></span> property.</p><p class="SHistory">Added in version 6.3 of package <span class="stt">base</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-value))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-value</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">id-stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">failure-thunk</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="data-structure-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%29%29" class="RktStxLink" data-pltdoc="x">any</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">failure-thunk</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%29%29" class="RktStxLink" data-pltdoc="x">any</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr></table></td><td valign="top"><span class="hspace"> </span></td><td valign="top">=</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVal">#f</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Returns the <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding value of <span class="RktVar">id-stx</span> in
either the context associated with <span class="RktVar">intdef-ctx</span> (if not
<span class="RktVal">#f</span>) or the context of the expression being expanded (if
<span class="RktVar">intdef-ctx</span> is <span class="RktVal">#f</span>). If <span class="RktVar">intdef-ctx</span> is
provided, it must be an extension of the context of the expression
being expanded.</div></p><p>If <span class="RktVar">id-stx</span> is bound to a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a> created
with <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span>, <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span>
effectively calls itself with the target of the rename and returns
that result, instead of the <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a>.</p><p>If <span class="RktVar">id-stx</span> has no <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding (via
<span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span>, <span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._let-syntax%29%29" class="RktStxLink" data-pltdoc="x">let-syntax</a></span>, etc.) in that
environment, the result is obtained by applying <span class="RktVar">failure-thunk</span>
if not <span class="RktVal">#f</span>. If <span class="RktVar">failure-thunk</span> is <span class="RktSym"><a href="booleans.html#%28def._%28%28lib._racket%2Fbool..rkt%29._false%29%29" class="RktValLink" data-pltdoc="x">false</a></span>, the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">swiss-cheeses?</span><span class="hspace"> </span><span class="RktVal">#t</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">transformer</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="if.html#%28form._%28%28quote._~23~25kernel%29._if%29%29" class="RktStxLink" data-pltdoc="x">if</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">swiss-cheeses?</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">gruyère</span><span class="hspace"> </span><span class="RktVal">emmental</span><span class="hspace"> </span><span class="RktVal">raclette</span><span class="RktVal">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktVal">'</span><span class="RktVal">(</span><span class="RktVal">roquefort</span><span class="hspace"> </span><span class="RktVal">camembert</span><span class="hspace"> </span><span class="RktVal">boursin</span><span class="RktVal">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">transformer</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktRes">'(gruyère emmental raclette)</span></p></td></tr></table></blockquote></td></tr></table></div><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">transformer-2</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">something-else</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._~ce~bb%29%29" class="RktStxLink" data-pltdoc="x">λ</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="exns.html#%28def._%28%28quote._~23~25kernel%29._error%29%29" class="RktValLink" data-pltdoc="x">error</a></span><span class="hspace"> </span><span class="RktVal">"no binding"</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">transformer-2</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktErr">no binding</span></p></td></tr></table></blockquote></td></tr></table></div><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">nachos</span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktVal">"nachos~n"</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktSym">chips</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">nachos</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">transformer-3</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktSym">chips</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">transformer-3</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktOut">nachos</span></p></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr></table></blockquote></td></tr></table></div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-value/immediate))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%2Fimmediate%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-value/immediate</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">id-stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">failure-thunk</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="data-structure-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%29%29" class="RktStxLink" data-pltdoc="x">any</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">failure-thunk</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%29%29" class="RktStxLink" data-pltdoc="x">any</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">intdef-ctx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._internal-definition-context~3f%29%29" class="RktValLink" data-pltdoc="x">internal-definition-context?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr></table></td><td valign="top"><span class="hspace"> </span></td><td valign="top">=</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVal">#f</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span>, but the result is normally two
values. If <span class="RktVar">id-stx</span> is bound to a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a>,
the results are the rename transformer and the identifier in the
transformer. <span class="refelem"><span class="refcolumn"><span class="refcontent">Beware that <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> on an
<span class="RktVar">id</span> bound to a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a> may export the
target of the rename instead of <span class="RktVar">id</span>. See
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-rename-transformer%29%29" class="RktValLink" data-pltdoc="x">make-rename-transformer</a></span> for more information.</span></span></span> If
<span class="RktVar">id-stx</span> is not bound to a <a href="syntax-model.html#%28tech._rename._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">rename transformer</span></a>, then the
results are the value that <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-value%29%29" class="RktValLink" data-pltdoc="x">syntax-local-value</a></span> would produce
and <span class="RktVal">#f</span>.</div></p><p>If <span class="RktVar">id-stx</span> has no transformer binding, then
<span class="RktVar">failure-thunk</span> is called (and it can return any number of
values), or an exception is raised if <span class="RktVar">failure-thunk</span> is
<span class="RktVal">#f</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-expression))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns a fresh identifier, and cooperates with the <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span>,
<span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._letrec-syntaxes%2Bvalues%29%29" class="RktStxLink" data-pltdoc="x">letrec-syntaxes+values</a></span>, <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-syntaxes%29%29" class="RktStxLink" data-pltdoc="x">define-syntaxes</a></span>,
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>, and top-level expanders to bind the
generated identifier to the expression <span class="RktVar">stx</span>.</div></p><p>A run-time expression within a module is lifted to the module’s top
level, just before the expression whose expansion requests the
lift. Similarly, a run-time expression outside of a module is lifted
to a top-level definition. A compile-time expression in a
<span class="RktSym"><a href="let.html#%28form._%28%28quote._~23~25kernel%29._letrec-syntaxes%2Bvalues%29%29" class="RktStxLink" data-pltdoc="x">letrec-syntaxes+values</a></span> or <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-syntaxes%29%29" class="RktStxLink" data-pltdoc="x">define-syntaxes</a></span> binding is
lifted to a <span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._let%29%29" class="RktStxLink" data-pltdoc="x">let</a></span> wrapper around the corresponding right-hand
side of the binding. A compile-time expression within
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span> is lifted to a <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span>
declaration just before the requesting expression within the
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>.</p><p>Other syntactic forms can capture lifts by using
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%2Fcapture-lifts%29%29" class="RktValLink" data-pltdoc="x">local-expand/capture-lifts</a></span> or
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-transformer-expand%2Fcapture-lifts%29%29" class="RktValLink" data-pltdoc="x">local-transformer-expand/capture-lifts</a></span>.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-values-expression))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-values-expression%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-values-expression</a></span></span><span class="hspace"> </span><span class="RktVar">n</span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">n</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-nonnegative-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-nonnegative-integer?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span>, but binds the result to
<span class="RktVar">n</span> identifiers, and returns a list of the <span class="RktVar">n</span>
identifiers.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-context))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-context%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-context</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns a value that represents the target for expressions lifted via
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span>. That is, for different
transformer calls for which this procedure returns the same value (as
determined by <span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._eq~3f%29%29" class="RktValLink" data-pltdoc="x">eq?</a></span>), lifted expressions for the two
transformer are moved to the same place. Thus, the result is useful
for caching lift information to avoid redundant lifts.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-module))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-module</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Cooperates with the <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form or top-level expansion to add
<span class="RktVar">stx</span> as a module declaration in the enclosing module or top-level.
The <span class="RktVar">stx</span> form must start with <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> or <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span>,
where the latter is only allowed within the expansion of a module.</div></p><p>The module is not immediately declared when
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-module</a></span> returns. Instead, the module
declaration is recorded for processing when expansion returns to the
enclosing module body or top-level sequence.</p><p><div class="SIntrapara">This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div><div class="SIntrapara"> If the current expression being transformed is not
within a <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form or within a top-level expansion, then
the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised. If <span class="RktVar">stx</span> form does start with
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> or <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span>, or if it starts with <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span>
in a top-level context, the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div></p><p class="SHistory">Added in version 6.3 of package <span class="stt">base</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-module-end-declaration))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-module-end-declaration%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-module-end-declaration</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Cooperates with the <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form to insert <span class="RktVar">stx</span> as
a top-level declaration at the end of the module currently being
expanded. If the current expression being
transformed is in <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> 0 and not in the module top-level, then <span class="RktVar">stx</span> is
eventually expanded in an expression context. If the current expression being
transformed is in a higher <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> (i.e., nested within some
number of <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>es within a module top-level), then the lifted declaration
is placed at the very end of the module (under a suitable number of
<span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>es), instead of merely the end of the
enclosing <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>.</div></p><p><div class="SIntrapara">This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div><div class="SIntrapara"> If the current expression being transformed is not
within a <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form (see <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming-module-expression~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming-module-expression?</a></span>),
then the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-require))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-require%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-require</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">raw-require-spec</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">stx</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">raw-require-spec</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Lifts a <span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25require%29%29" class="RktStxLink" data-pltdoc="x">#%require</a></span> form corresponding to
<span class="RktVar">raw-require-spec</span> (either as a <a href="syntax-model.html#%28tech._syntax._object%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax object</span></a> or datum)
to the top-level or to the top of the module currently being expanded
or to an enclosing <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>..</div></p><p>The resulting syntax object is the same as <span class="RktVar">stx</span>, except that a
fresh <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> is added. The same <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> is
added to the lifted <span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25require%29%29" class="RktStxLink" data-pltdoc="x">#%require</a></span> form, so that the
<span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25require%29%29" class="RktStxLink" data-pltdoc="x">#%require</a></span> form can bind uses of imported identifiers in the
resulting syntax object (assuming that the lexical information of
<span class="RktVar">stx</span> includes the binding environment into which the
<span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25require%29%29" class="RktStxLink" data-pltdoc="x">#%require</a></span> is lifted).</p><p>If <span class="RktVar">raw-require-spec</span> and <span class="RktVar">stx</span> are part of the input to
a transformer, then typically <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-introduce%29%29" class="RktValLink" data-pltdoc="x">syntax-local-introduce</a></span> should be
applied to each before passing them to
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-require%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-require</a></span>, and then
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-introduce%29%29" class="RktValLink" data-pltdoc="x">syntax-local-introduce</a></span> should be applied to the result of
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-require%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-require</a></span>. Otherwise, marks added
by the macro expander can prevent access to the new imports.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-lift-provide))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-provide%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-lift-provide</a></span></span><span class="hspace"> </span><span class="RktVar">raw-provide-spec-stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">raw-provide-spec-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Lifts a <span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25provide%29%29" class="RktStxLink" data-pltdoc="x">#%provide</a></span> form corresponding to
<span class="RktVar">raw-provide-spec-stx</span> to the top of the module currently being
expanded or to an enclosing <span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span>.</div></p><p><div class="SIntrapara">This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div><div class="SIntrapara"> If the current expression being transformed is not
within a <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form (see <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming-module-expression~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming-module-expression?</a></span>),
then the <span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-name))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-name%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-name</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns an inferred name for the expression position being
transformed, or <span class="RktVal">#f</span> if no such name is available. A name is
normally a symbol or an identifier. See also <a href="syntax-model.html#%28part._infernames%29" data-pltdoc="x">Inferred Value Names</a>.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-context))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-context</a></span></span><span class="RktPn"></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">expression</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">top-level</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">module-begin</span><span class="hspace"> </span><span class="RktSym"><a href="pairs.html#%28def._%28%28quote._~23~25kernel%29._list~3f%29%29" class="RktValLink" data-pltdoc="x">list?</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Returns an indication of the context for expansion that triggered a
<a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> call. See <a href="syntax-model.html#%28part._expand-context-model%29" data-pltdoc="x">Expansion Context</a>
for more information on contexts.</div></p><p>The symbol results indicate that the expression is being expanded for
an <a href="syntax-model.html#%28tech._expression._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">expression context</span></a>, a <a href="syntax-model.html#%28tech._top._level._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">top-level context</span></a>, a
<a href="syntax-model.html#%28tech._module._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">module context</span></a>, or a <a href="syntax-model.html#%28tech._module._begin._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">module-begin context</span></a>.</p><p>A list result indicates expansion in an <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition
context</span></a>. The identity of the list’s first element (i.e., its
<span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._eq~3f%29%29" class="RktValLink" data-pltdoc="x">eq?</a></span>ness) reflects the identity of the internal-definition
context; in particular two transformer expansions receive the same
first value if and only if they are invoked for the same
<a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a>. Later values in the list similarly
identify <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition contexts</span></a> that are still being expanded,
and that required the expansion of nested internal-definition
contexts.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-phase-level))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">During the dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application
by the expander, the result is the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> of the form
being expanded. Otherwise, the result is <span class="RktVal">0</span>.</div></p><p><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><p>Examples:</p></td></tr><tr><td><blockquote class="SCodeFlow"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">a macro bound at phase 0</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">print-phase-level</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktVal">"phase level: ~a~n"</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void%29%29" class="RktValLink" data-pltdoc="x">void</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._for-meta%29%29" class="RktStxLink" data-pltdoc="x">for-meta</a></span><span class="hspace"> </span><span class="RktVal">2</span><span class="hspace"> </span><span class="RktSym">racket/base</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktCmt">;</span><span class="RktCmt"> </span><span class="RktCmt">a macro bound at phase 1</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">print-phase-level</span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Writing.html#%28def._%28%28quote._~23~25kernel%29._printf%29%29" class="RktValLink" data-pltdoc="x">printf</a></span><span class="hspace"> </span><span class="RktVal">"phase level: ~a~n"</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="hspace"> </span><span class="RktRdr">#'</span><span class="RktPn">(</span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void%29%29" class="RktValLink" data-pltdoc="x">void</a></span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym">print-phase-level</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktOut">phase level: 0</span></p></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr><tr><td><span class="stt">> </span><span class="RktPn">(</span><span class="RktSym"><a href="begin.html#%28form._%28%28quote._~23~25kernel%29._begin-for-syntax%29%29" class="RktStxLink" data-pltdoc="x">begin-for-syntax</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">print-phase-level</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><p><span class="RktOut">phase level: 1</span></p></td></tr><tr><td><table cellspacing="0" cellpadding="0"><tr><td></td></tr></table></td></tr></table></blockquote></td></tr></table></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-module-exports))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-exports%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-module-exports</a></span></span><span class="hspace"> </span><span class="RktVar">mod-path</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._symbol~3f%29%29" class="RktValLink" data-pltdoc="x">symbol?</a></span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">mod-path</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-~3edatum%29%29" class="RktValLink" data-pltdoc="x">syntax->datum</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Returns an association list from <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase-level</span></a> numbers (or
<span class="RktVal">#f</span> for the <a href="syntax-model.html#%28tech._label._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">label phase level</span></a>) to lists of symbols,
where the symbols are the names of <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span>d
bindings from <span class="RktVar">mod-path</span> at the corresponding <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a>.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-submodules))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-submodules%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-submodules</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._symbol~3f%29%29" class="RktValLink" data-pltdoc="x">symbol?</a></span><span class="RktPn">)</span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns a list of submodule names that are declared via
<span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> (as opposed to <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%2A%29%29" class="RktStxLink" data-pltdoc="x">module*</a></span>) in the current
expansion context.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-get-shadower))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-get-shadower%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-get-shadower</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">id-stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">only-generated?</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">only-generated?</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr></table></blockquote></div><div class="SIntrapara">Adds <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> to <span class="RktVar">id-stx</span> so that it refers to bindings
in the current expansion context or could bind any identifier obtained
via <span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-get-shadower%29%29" class="RktValLink" data-pltdoc="x">syntax-local-get-shadower</a></span><span class="stt"> </span><span class="RktVar">id-stx</span><span class="RktPn">)</span> in more nested contexts.
If <span class="RktVar">only-generated?</span> is true, the phase-spanning <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a>
of the enclosing module or namespace is omitted from the added scopes,
however, which limits the bindings that can be referenced (and
therefore avoids certain ambiguous references).</div></p><p>This function is intended for the implementation of
<span class="RktSym">syntax-parameterize</span> and <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._local-require%29%29" class="RktStxLink" data-pltdoc="x">local-require</a></span>.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: Simplified to the minimal functionality
needed for <span class="RktSym">syntax-parameterize</span>
and <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._local-require%29%29" class="RktStxLink" data-pltdoc="x">local-require</a></span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-make-delta-introducer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-make-delta-introducer%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-make-delta-introducer</a></span></span><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="procedures.html#%28def._%28%28quote._~23~25kernel%29._procedure~3f%29%29" class="RktValLink" data-pltdoc="x">procedure?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">For (limited) backward compatibility only; raises <span class="RktSym">exn:fail:supported</span>.</div></p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: changed to raise <span class="RktSym">exn:fail:supported</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/private/base..rkt)._syntax-local-certifier))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._syntax-local-certifier%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-certifier</a></span></span><span class="hspace"> </span>[<span class="RktVar">active?</span>]<span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="procedures.html#%28def._%28%28quote._~23~25kernel%29._procedure~3f%29%29" class="RktValLink" data-pltdoc="x">procedure?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%2A%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span>*</a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">active?</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr></table></blockquote></div><div class="SIntrapara">For backward compatibility only; returns a procedure that returns its
first argument.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-transforming~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-transforming?</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> during the dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax
transformer</span></a> application by the expander and while a module is being
<a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-transforming-module-expression~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming-module-expression~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-transforming-module-expression?</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> during the dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax
transformer</span></a> application by the expander for an expression
within a <span class="RktSym"><a href="module.html#%28form._%28%28quote._~23~25kernel%29._module%29%29" class="RktStxLink" data-pltdoc="x">module</a></span> form, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-identifier-as-binding))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-identifier-as-binding%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-identifier-as-binding</a></span></span><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">id-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns an identifier like <span class="RktVar">id-stx</span>, but without <a href="syntax-model.html#%28tech._use._site._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">use-site
scopes</span></a> that were previously added to the identifier as part of a
macro expansion in the current definition context.</div></p><p>In a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> that runs in a non-expression context
and forces the expansion of subforms with <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span>, use
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-identifier-as-binding%29%29" class="RktValLink" data-pltdoc="x">syntax-local-identifier-as-binding</a></span> on an identifier from the
expansion before moving it into a binding position or comparing with
with <span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._bound-identifier~3d~3f%29%29" class="RktValLink" data-pltdoc="x">bound-identifier=?</a></span>. Otherwise, the results can be
inconsistent with the way that <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span> works in the same
definition context.</p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p class="SHistory">Added in version 6.3 of package <span class="stt">base</span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-introduce))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-introduce%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-introduce</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Produces a syntax object that is like <span class="RktVar">stx</span>, except that the
presence of <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> for the current expansion—<wbr></wbr>both the
macro-introduction scope and the use-site scope, if any—<wbr></wbr>is flipped
on all parts of the syntax object. See <a href="syntax-model.html#%28part._transformer-model%29" data-pltdoc="x">Transformer Bindings</a> for information
on macro-introduction and use-site <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a>.</div></p><p>This procedure must be called during the
dynamic extent of a <a href="syntax-model.html#%28tech._syntax._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax transformer</span></a> application by the
expander or while a module is <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed (see
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-transforming~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-transforming?</a></span>), otherwise the
<span class="RktSym"><a href="exns.html#%28def._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._exn~3afail~3acontract%29%29" class="RktValLink" data-pltdoc="x">exn:fail:contract</a></span> exception is raised.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._make-syntax-introducer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-introducer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-syntax-introducer</a></span></span><span class="hspace"> </span>[<span class="RktVar">as-use-site?</span>]<span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">flip</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">add</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">remove</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%2A%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span>*</a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">as-use-site?</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span><span class="hspace"> </span>=<span class="hspace"> </span><span class="RktVal">#f</span></td></tr></table></blockquote></div><div class="SIntrapara">Produces a procedure that encapsulates a fresh <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scope</span></a> and flips,
adds, or removes it in a given syntax object. By default, the fresh
scope is a macro-introduction scope, but providing a true value for
<span class="RktVar">as-use-site?</span> creates a scope that is like a use-site scope;
the difference is in how the scopes are treated by
<span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-original~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-original?</a></span>.</div></p><p>The action of the generated procedure can be <span class="RktVal">'</span><span class="RktVal">flip</span> (the
default) to flip the presence of a scope in each part of a given
syntax object, <span class="RktVal">'</span><span class="RktVal">add</span> to add the scope to each regardless of
whether it is present already, or <span class="RktVal">'</span><span class="RktVal">remove</span> to remove the scope
when it is currently present in any part.</p><p>Multiple applications of the same
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-introducer%29%29" class="RktValLink" data-pltdoc="x">make-syntax-introducer</a></span> result procedure use the same scope,
and different result procedures use distinct scopes.</p><p class="SHistory">Changed in version 6.3 of package <span class="stt">base</span>: Added the optional
<span class="RktVar">as-use-site?</span> argument, and
added the optional operation argument
in the result procedure.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._make-syntax-delta-introducer))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-delta-introducer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-syntax-delta-introducer</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">ext-stx</span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">base-stx</span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span>[</td><td valign="top"><span class="RktVar">phase-level</span>]<span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">flip</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">add</span><span class="hspace"> </span><span class="RktVal">'</span><span class="RktVal">remove</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%2A%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span>*</a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">ext-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">base-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">phase-level</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="RktPn">)</span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">=</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktPn">(</span><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Produces a procedure that behaves like the result of
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._make-syntax-introducer%29%29" class="RktValLink" data-pltdoc="x">make-syntax-introducer</a></span>, but using the <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> of
<span class="RktVar">ext-stx</span> that are not shared with <span class="RktVar">base-stx</span>.</div></p><p>This procedure is potentially useful when <span class="RktVar">m-id</span> has a
transformer binding that records some <span class="RktVar">orig-id</span>, and a use of
<span class="RktVar">m-id</span> introduces a binding of <span class="RktVar">orig-id</span>. In that
case, the <a href="syntax-model.html#%28tech._scope%29" class="techoutside" data-pltdoc="x"><span class="techinside">scopes</span></a> one the use of <span class="RktVar">m-id</span> added since the
binding of <span class="RktVar">m-id</span> should be transferred to the binding
instance of <span class="RktVar">orig-id</span>, so that it captures uses with the same
lexical context as the use of <span class="RktVar">m-id</span>.</p><p>If <span class="RktVar">ext-stx</span> is <a href="stxcerts.html#%28tech._tainted%29" class="techoutside" data-pltdoc="x"><span class="techinside">tainted</span></a> or <a href="stxcerts.html#%28tech._armed%29" class="techoutside" data-pltdoc="x"><span class="techinside">armed</span></a>, then an
identifier result from the created procedure is <a href="stxcerts.html#%28tech._tainted%29" class="techoutside" data-pltdoc="x"><span class="techinside">tainted</span></a>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-transforming-module-provides~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-transforming-module-provides~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-transforming-module-provides?</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> while a <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformer</span></a> is running (see
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-transformer%29%29" class="RktValLink" data-pltdoc="x">make-provide-transformer</a></span>) or while an <span class="RktSym">expand</span> sub-form of
<span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25provide%29%29" class="RktStxLink" data-pltdoc="x">#%provide</a></span> is expanded, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-module-defined-identifiers))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-defined-identifiers%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-module-defined-identifiers</a></span></span><span class="RktPn"></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="hashtables.html#%28def._%28%28quote._~23~25kernel%29._hash~3f%29%29" class="RktValLink" data-pltdoc="x">hash?</a></span><span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._immutable~3f%29%29" class="RktValLink" data-pltdoc="x">immutable?</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Can be called only while
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-transforming-module-provides~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-local-transforming-module-provides?</a></span> returns
<span class="RktVal">#t</span>.</div></p><p>It returns a hash table mapping a <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase-level</span></a> number (such as
<span class="RktVal">0</span>) to a list of all definitions at that <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a>
within the module being expanded. This information is used for
implementing <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> sub-forms like <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._all-defined-out%29%29" class="RktStxLink" data-pltdoc="x">all-defined-out</a></span>.</p><p>Beware that the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase-level</span></a> keys are absolute relative to the
enclosing module, and not relative to the current transformer phase
level as reported by <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._syntax-local-module-required-identifiers))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-module-required-identifiers%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-module-required-identifiers</a></span></span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">mod-path</span></td><td valign="top"><span class="hspace"> </span></td></tr><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">phase-level</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td></tr></table></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">mod-path</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">phase-level</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktVal">#t</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Can be called only while
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-transforming-module-provides~3f%29%29" class="RktValLink" data-pltdoc="x">syntax-local-transforming-module-provides?</a></span> returns
<span class="RktVal">#t</span>.</div></p><p>It returns an association list mapping phase levels to lists of
identifiers. Each list of identifiers includes all bindings imported
(into the module being expanded) using the module path
<span class="RktVar">mod-path</span>, or all modules if <span class="RktVar">mod-path</span> is
<span class="RktVal">#f</span>. The association list includes all identifiers imported
with a <span class="RktVar">phase-level</span> shift, of all shifts if
<span class="RktVar">phase-level</span> is <span class="RktVal">#t</span>.</p><p>When an identifier is renamed on import, the result association list
includes the identifier by its internal name. Use
<span class="RktSym"><a href="stxcmp.html#%28def._%28%28quote._~23~25kernel%29._identifier-binding%29%29" class="RktValLink" data-pltdoc="x">identifier-binding</a></span> to obtain more information about the
identifier.</p><p>Beware that the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase-level</span></a> keys are absolute relative to the
enclosing module, and not relative to the current transformer phase
level as reported by <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-phase-level%29%29" class="RktValLink" data-pltdoc="x">syntax-local-phase-level</a></span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><table cellspacing="0" cellpadding="0" class="together"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((quote._~23~25kernel)._prop~3aliberal-define-context))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aliberal-define-context%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:liberal-define-context</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="together"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((quote._~23~25kernel)._liberal-define-context~3f))"></a><span title="Provided from: racket/base, racket | Package: base"><span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._liberal-define-context~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">liberal-define-context?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">An instance of a structure type with a true value for the
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aliberal-define-context%29%29" class="RktValLink" data-pltdoc="x">prop:liberal-define-context</a></span> property can be used as an
element of an <a href="syntax-model.html#%28tech._internal._definition._context%29" class="techoutside" data-pltdoc="x"><span class="techinside">internal-definition context</span></a> representation in the
result of <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-context%29%29" class="RktValLink" data-pltdoc="x">syntax-local-context</a></span> or the second argument of
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._local-expand%29%29" class="RktValLink" data-pltdoc="x">local-expand</a></span>. Such a value indicates that the context
supports <a name="(tech._liberal._expansion)"></a><span style="font-style: italic">liberal expansion</span> of <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._define%29%29" class="RktStxLink" data-pltdoc="x">define</a></span> forms into
potentially multiple <span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-values%29%29" class="RktStxLink" data-pltdoc="x">define-values</a></span> and
<span class="RktSym"><a href="define.html#%28form._%28%28quote._~23~25kernel%29._define-syntaxes%29%29" class="RktStxLink" data-pltdoc="x">define-syntaxes</a></span> forms. The <span class="RktVal">'</span><span class="RktVal">module</span> and
<span class="RktVal">'</span><span class="RktVal">module-body</span> contexts implicitly allow <a href="#%28tech._liberal._expansion%29" class="techoutside" data-pltdoc="x"><span class="techinside">liberal
expansion</span></a>.</div></p><p>The <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._liberal-define-context~3f%29%29" class="RktValLink" data-pltdoc="x">liberal-define-context?</a></span> predicate returns <span class="RktVal">#t</span> if
<span class="RktVar">v</span> is an instance of a structure with a true value for the
<span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._prop~3aliberal-define-context%29%29" class="RktValLink" data-pltdoc="x">prop:liberal-define-context</a></span> property, <span class="RktVal">#f</span> otherwise.</p><h5 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""require-trans"">12.4.1<tt> </tt><a name="(part._require-trans)"></a><a name="(mod-path._racket/require-transform)"></a><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> Transformers</h5><p><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="stt"> </span><a href="#%28mod-path._racket%2Frequire-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/require-transform</span></a><span class="RktPn">)</span></td><td align="right"><span class="RpackageSpec"><span class="Smaller"> package:</span> <span class="stt">base</span></span></td></tr></table></div><div class="SIntrapara">The bindings documented in this section are provided by the <a href="#%28mod-path._racket%2Frequire-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/require-transform</span></a> library, not <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/base</span></a> or <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a>.</div></p><p>A <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding whose value is a structure with the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._prop~3arequire-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:require-transformer</a></span> property implements a derived
<span class="RktVar">require-spec</span> for <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> as a <a name="(tech._require._transformer)"></a><span style="font-style: italic">require
transformer</span>.</p><p>A <a href="#%28tech._require._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">require transformer</span></a> is called with the syntax object representing its use
as a <span class="RktVar">require-spec</span> within a <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> form, and the
result must be two lists: a list of <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import%29%29" class="RktValLink" data-pltdoc="x">import</a></span>s and a list of
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import-source%29%29" class="RktValLink" data-pltdoc="x">import-source</a></span>s.</p><p>If the derived form contains a sub-form that is a
<span class="RktVar">require-spec</span>, then it can call <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._expand-import%29%29" class="RktValLink" data-pltdoc="x">expand-import</a></span> to
transform the sub-<span class="RktVar">require-spec</span> to lists of imports and
import sources.</p><p>See also <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Frequire-syntax..rkt%29._define-require-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-require-syntax</a></span>, which supports macro-style
<span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> transformers.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><table cellspacing="0" cellpadding="0" class="prototype RForeground"><tr><td valign="top"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._expand-import))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._expand-import%29%29" class="RktValDef RktValLink" data-pltdoc="x">expand-import</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import~3f%29%29" class="RktValLink" data-pltdoc="x">import?</a></span><span class="RktPn">)</span></td><td><span class="hspace"> </span></td><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import-source~3f%29%29" class="RktValLink" data-pltdoc="x">import-source?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Expands the given <span class="RktVar">require-spec</span> to lists of imports and
import sources. The latter specifies modules to be
<a href="eval-model.html#%28tech._instantiate%29" class="techoutside" data-pltdoc="x"><span class="techinside">instantiate</span></a>d or <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed, so the modules that it
represents should be a superset of the modules represented in the
former list (so that a module will be <a href="eval-model.html#%28tech._instantiate%29" class="techoutside" data-pltdoc="x"><span class="techinside">instantiate</span></a>d or
<a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed even if all of imports are eventually filtered from the
former list).</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._make-require-transformer))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._make-require-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-require-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">proc</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._require-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">require-transformer?</a></span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">proc</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="values.html#%28def._%28%28quote._~23~25kernel%29._values%29%29" class="RktValLink" data-pltdoc="x">values</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import~3f%29%29" class="RktValLink" data-pltdoc="x">import?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import-source~3f%29%29" class="RktValLink" data-pltdoc="x">import-source?</a></span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Creates a <a href="#%28tech._require._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">require transformer</span></a> using the given procedure as the
transformer.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((lib._racket/require-transform..rkt)._prop~3arequire-transformer))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._prop~3arequire-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:require-transformer</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A property to identify <a href="#%28tech._require._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">require transformers</span></a>. The property
value must be a procedure that takes the structure and returns a transformer
procedure; the returned transformer procedure takes a syntax object and returns
import and import-source lists.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._require-transformer~3f))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._require-transformer~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">require-transformer?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> has the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._prop~3arequire-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:require-transformer</a></span> property, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>struct</p></div></div><table cellspacing="0" cellpadding="0" class="RForeground"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="define-struct.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._struct%29%29" class="RktStxLink" data-pltdoc="x">struct</a></span></td><td><span class="hspace"> </span></td><td><span class="nobreak"><a name="(def._((lib._racket/require-transform..rkt)._import-orig-stx))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-orig-mode))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-req-mode))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-mode))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-src-mod-path))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-src-sym))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-local-id))"></a><a name="(def._((lib._racket/require-transform..rkt)._make-import))"></a><a name="(def._((lib._racket/require-transform..rkt)._import~3f))"></a><a name="(def._((lib._racket/require-transform..rkt)._struct~3aimport))"></a><a name="(def._((lib._racket/require-transform..rkt)._import))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import%29%29" class="RktValDef RktValLink" data-pltdoc="x">import</a></span></span></span></td><td><span class="hspace"> </span><span class="RktPn">(</span></td><td><span class="nobreak"><span class="RktSym">local-id</span></span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">src-sym</span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">src-mod-path</span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">mode</span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">req-mode</span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">orig-mode</span></td></tr><tr><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="hspace"> </span></td><td><span class="RktSym">orig-stx</span><span class="RktPn">)</span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">#:extra-constructor-name</span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._make-import%29%29" class="RktValLink" data-pltdoc="x">make-import</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">local-id</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">src-sym</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._symbol~3f%29%29" class="RktValLink" data-pltdoc="x">symbol?</a></span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym">src-mod-path</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-~3edatum%29%29" class="RktValLink" data-pltdoc="x">syntax->datum</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">req-mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">orig-mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">orig-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">A structure representing a single imported identifier:</div></p><ul><li><p><span class="RktSym">local-id</span> —<wbr></wbr> the identifier to be bound within the
importing module.</p></li><li><p><span class="RktSym">src-sym</span> —<wbr></wbr> the external name of the binding as
exported from its source module.</p></li><li><p><span class="RktSym">src-mod-path</span> —<wbr></wbr> a <a href="Module_Names_and_Loading.html#%28tech._module._path%29" class="techoutside" data-pltdoc="x"><span class="techinside">module path</span></a> (relative to the
importing module) for the source of the imported binding.</p></li><li><p><span class="RktSym">orig-stx</span> —<wbr></wbr> a <a href="syntax-model.html#%28tech._syntax._object%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax object</span></a> for the source of
the import, used for error reporting.</p></li><li><p><span class="RktSym">mode</span> —<wbr></wbr> the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> of the binding in the
importing module.</p></li><li><p><span class="RktSym">req-mode</span> —<wbr></wbr> the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> shift of the
import relative to the exporting module.</p></li><li><p><span class="RktSym">orig-mode</span> —<wbr></wbr> the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> of the
binding as exported by the exporting module.</p></li></ul><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>struct</p></div></div><table cellspacing="0" cellpadding="0" class="RForeground"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="define-struct.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._struct%29%29" class="RktStxLink" data-pltdoc="x">struct</a></span></td><td><span class="hspace"> </span></td><td><a name="(def._((lib._racket/require-transform..rkt)._import-source-mode))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-source-mod-path-stx))"></a><a name="(def._((lib._racket/require-transform..rkt)._make-import-source))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-source~3f))"></a><a name="(def._((lib._racket/require-transform..rkt)._struct~3aimport-source))"></a><a name="(def._((lib._racket/require-transform..rkt)._import-source))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._import-source%29%29" class="RktValDef RktValLink" data-pltdoc="x">import-source</a></span></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">mod-path-stx</span><span class="stt"> </span><span class="RktSym">mode</span><span class="RktPn">)</span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">#:extra-constructor-name</span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._make-import-source%29%29" class="RktValLink" data-pltdoc="x">make-import-source</a></span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktSym">mod-path-stx</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">x</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-~3edatum%29%29" class="RktValLink" data-pltdoc="x">syntax->datum</a></span><span class="hspace"> </span><span class="RktSym">x</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">A structure representing an imported module, which must be
<a href="eval-model.html#%28tech._instantiate%29" class="techoutside" data-pltdoc="x"><span class="techinside">instantiate</span></a>d or <a href="syntax-model.html#%28tech._visit%29" class="techoutside" data-pltdoc="x"><span class="techinside">visit</span></a>ed even if no binding is imported
into a module.</div></p><ul><li><p><span class="RktSym">mod-path-stx</span> —<wbr></wbr> a <a href="Module_Names_and_Loading.html#%28tech._module._path%29" class="techoutside" data-pltdoc="x"><span class="techinside">module path</span></a> (relative
to the importing module) for the source of the imported binding.</p></li><li><p><span class="RktSym">mode</span> —<wbr></wbr> the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> shift of the import.</p></li></ul><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>parameter</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._current-require-module-path))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-require-module-path</a></span></span><span class="RktPn"></span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path-index~3f%29%29" class="RktValLink" data-pltdoc="x">module-path-index?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="RktPn">(</span><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValDef RktValLink" data-pltdoc="x">current-require-module-path</a></span></span><span class="hspace"> </span><span class="RktVar">module-path</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="void.html#%28def._%28%28quote._~23~25kernel%29._void~3f%29%29" class="RktValLink" data-pltdoc="x">void?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">module-path</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path-index~3f%29%29" class="RktValLink" data-pltdoc="x">module-path-index?</a></span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">A <a href="eval-model.html#%28tech._parameter%29" class="techoutside" data-pltdoc="x"><span class="techinside">parameter</span></a> that determines how relative <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span>-level module
paths are expanded to <span class="RktSym"><a href="require.html#%28form._%28%28quote._~23~25kernel%29._~23~25require%29%29" class="RktStxLink" data-pltdoc="x">#%require</a></span>-level module paths by
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._convert-relative-module-path%29%29" class="RktValLink" data-pltdoc="x">convert-relative-module-path</a></span> (which is used implicitly by all
built-in <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> sub-forms).</div></p><p>When the value of <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValLink" data-pltdoc="x">current-require-module-path</a></span> is <span class="RktVal">#f</span>,
relative module paths are left as-is, which means that the
<span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> context determines the resolution of the module
path.</p><p>The <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span> form <span class="RktSym"><a href="parameters.html#%28form._%28%28lib._racket%2Fprivate%2Fmore-scheme..rkt%29._parameterize%29%29" class="RktStxLink" data-pltdoc="x">parameterize</a></span>s
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValLink" data-pltdoc="x">current-require-module-path</a></span> as <span class="RktVal">#f</span> while invoking
sub-form transformers, while <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._relative-in%29%29" class="RktStxLink" data-pltdoc="x">relative-in</a></span> <span class="RktSym"><a href="parameters.html#%28form._%28%28lib._racket%2Fprivate%2Fmore-scheme..rkt%29._parameterize%29%29" class="RktStxLink" data-pltdoc="x">parameterize</a></span>s
to a given module path.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._convert-relative-module-path))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._convert-relative-module-path%29%29" class="RktValDef RktValLink" data-pltdoc="x">convert-relative-module-path</a></span></span><span class="hspace"> </span><span class="RktVar">module-path</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-e%29%29" class="RktValLink" data-pltdoc="x">syntax-e</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">module-path</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">stx</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="Module_Names_and_Loading.html#%28def._%28%28quote._~23~25kernel%29._module-path~3f%29%29" class="RktValLink" data-pltdoc="x">module-path?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax-e%29%29" class="RktValLink" data-pltdoc="x">syntax-e</a></span><span class="hspace"> </span><span class="RktSym">stx</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Converts <span class="RktVar">module-path</span> according to <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValLink" data-pltdoc="x">current-require-module-path</a></span>.</div></p><p>If <span class="RktVar">module-path</span> is not relative or if the value of
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValLink" data-pltdoc="x">current-require-module-path</a></span> is <span class="RktVal">#f</span>, then
<span class="RktVar">module-path</span> is returned. Otherwise, <span class="RktVar">module-path</span> is
converted to an absolute module path that is equivalent to
<span class="RktVar">module-path</span> relative to the value of
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._current-require-module-path%29%29" class="RktValLink" data-pltdoc="x">current-require-module-path</a></span>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/require-transform..rkt)._syntax-local-require-certifier))"></a><span title="Provided from: racket/require-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Frequire-transform..rkt%29._syntax-local-require-certifier%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-require-certifier</a></span></span><span class="RktPn"></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%2A%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span>*</a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">For backward compatibility only; returns a procedure that returns its
first argument.</div></p><h5 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""provide-trans"">12.4.2<tt> </tt><a name="(part._provide-trans)"></a><a name="(mod-path._racket/provide-transform)"></a><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> Transformers</h5><p><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="stt"> </span><a href="#%28mod-path._racket%2Fprovide-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/provide-transform</span></a><span class="RktPn">)</span></td><td align="right"><span class="RpackageSpec"><span class="Smaller"> package:</span> <span class="stt">base</span></span></td></tr></table></div><div class="SIntrapara">The bindings documented in this section are provided by the <a href="#%28mod-path._racket%2Fprovide-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/provide-transform</span></a> library, not <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/base</span></a> or <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a>.</div></p><p>A <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding whose value is a structure with the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:provide-transformer</a></span> property implements a derived
<span class="RktVar">provide-spec</span> for <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> as a <a name="(tech._provide._transformer)"></a><span style="font-style: italic">provide transformer</span>.
A <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformer</span></a> is applied as part of the last phase of
a module’s expansion, after all other declarations and expressions within
the module are expanded.</p><p>A <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding whose value is a structure with the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-pre-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:provide-pre-transformer</a></span> property implements a derived
<span class="RktVar">provide-spec</span> for <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> as a <a name="(tech._provide._pre._transformer)"></a><span style="font-style: italic">provide
pre-transformer</span>. A <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a> is applied as part
of the first phase of a module’s expansion. Since it is used in the
first phase, a <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a> can use functions such
as <span class="RktSym"><a href="#%28def._%28%28quote._~23~25kernel%29._syntax-local-lift-expression%29%29" class="RktValLink" data-pltdoc="x">syntax-local-lift-expression</a></span> to introduce expressions and
definitions in the enclosing module.</p><p>An identifier can have a <a href="syntax-model.html#%28tech._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">transformer</span></a> binding to a value that
acts both as a <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformer</span></a> and <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide
pre-transformer</span></a>. The result of a <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide
pre-transformer</span></a> is <span style="font-style: italic">not</span> automatically re-expanded, so a
<a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a> can usefully expand to itself in that case.</p><p>A transformer is called with the syntax object representing its use as
a <span class="RktVar">provide-spec</span> within a <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span> form and a list of
symbols representing the export modes specified by enclosing
<span class="RktVar">provide-spec</span>s. The result of a <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformer</span></a>
must be a list of <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export%29%29" class="RktValLink" data-pltdoc="x">export</a></span>s, while the result of a
<a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a> is a syntax object to be used as a
<span class="RktVar">provide-spec</span> in the last phase of module expansion.</p><p>If a derived form contains a sub-form that is a
<span class="RktVar">provide-spec</span>, then it can call <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._expand-export%29%29" class="RktValLink" data-pltdoc="x">expand-export</a></span> or
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._pre-expand-export%29%29" class="RktValLink" data-pltdoc="x">pre-expand-export</a></span> to transform the sub-<span class="RktVar">provide-spec</span>
sub-form.</p><p>See also <span class="RktSym"><a href="define.html#%28form._%28%28lib._racket%2Fprovide-syntax..rkt%29._define-provide-syntax%29%29" class="RktStxLink" data-pltdoc="x">define-provide-syntax</a></span>, which supports macro-style
<a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformers</span></a>.</p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._expand-export))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._expand-export%29%29" class="RktValDef RktValLink" data-pltdoc="x">expand-export</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span><span class="RktVar">modes</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export~3f%29%29" class="RktValLink" data-pltdoc="x">export?</a></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">modes</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Expands the given <span class="RktVar">provide-spec</span> to a list of exports. The
<span class="RktVar">modes</span> list controls the expansion of
sub-<span class="RktVar">provide-specs</span>; for example, an identifier refers to a
binding in the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> of the enclosing <span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._provide%29%29" class="RktStxLink" data-pltdoc="x">provide</a></span>
form, unless the <span class="RktVar">modes</span> list specifies otherwise. Normally,
<span class="RktVar">modes</span> is either empty or contains a single element.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._pre-expand-export))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._pre-expand-export%29%29" class="RktValDef RktValLink" data-pltdoc="x">pre-expand-export</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span><span class="RktVar">modes</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">modes</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></blockquote></div><div class="SIntrapara">Expands the given <span class="RktVar">provide-spec</span> at the level of <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide
pre-transformers</span></a>. The <span class="RktVar">modes</span> argument is the same as for
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._expand-export%29%29" class="RktValLink" data-pltdoc="x">expand-export</a></span>.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._make-provide-transformer))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-provide-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">proc</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">provide-transformer?</a></span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">proc</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export~3f%29%29" class="RktValLink" data-pltdoc="x">export?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="RktPn">(</span><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-provide-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">proc</span><span class="hspace"> </span><span class="RktVar">pre-proc</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._and%2Fc%29%29" class="RktValLink" data-pltdoc="x">and/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">provide-transformer?</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-pre-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">provide-pre-transformer?</a></span><span class="RktPn">)</span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">proc</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export~3f%29%29" class="RktValLink" data-pltdoc="x">export?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">pre-proc</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Creates a <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformer</span></a> (i.e., a structure with the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:provide-transformer</a></span> property) using the given procedure
as the transformer. If a <span class="RktVar">pre-proc</span> is provided, then the result is also a
<a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a>.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._make-provide-pre-transformer))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-pre-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">make-provide-pre-transformer</a></span></span><span class="hspace"> </span><span class="RktVar">pre-proc</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-pre-transformer~3f%29%29" class="RktValLink" data-pltdoc="x">provide-pre-transformer?</a></span></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="argcontract"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top"><span class="RktVar">pre-proc</span></td><td valign="top"><span class="hspace"> </span></td><td valign="top">:</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._listof%29%29" class="RktValLink" data-pltdoc="x">listof</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Like <span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-provide-transformer%29%29" class="RktValLink" data-pltdoc="x">make-provide-transformer</a></span>, but for a value that is a
<a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformer</span></a>, only.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((lib._racket/provide-transform..rkt)._prop~3aprovide-transformer))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:provide-transformer</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A property to identify <a href="#%28tech._provide._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide transformers</span></a>. The property
value must be a procedure that takes the structure and returns a transformer
procedure; the returned transformer procedure takes a syntax object and mode list and
returns an export list.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>value</p></div></div><p class="RForeground"><a name="(def._((lib._racket/provide-transform..rkt)._prop~3aprovide-pre-transformer))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-pre-transformer%29%29" class="RktValDef RktValLink" data-pltdoc="x">prop:provide-pre-transformer</a></span></span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="structprops.html#%28def._%28%28quote._~23~25kernel%29._struct-type-property~3f%29%29" class="RktValLink" data-pltdoc="x">struct-type-property?</a></span></p></blockquote></td></tr></table></blockquote></div><div class="SIntrapara">A property to identify <a href="#%28tech._provide._pre._transformer%29" class="techoutside" data-pltdoc="x"><span class="techinside">provide pre-transformers</span></a>. The property
value must be a procedure that takes the structure and returns a transformer
procedure; the returned transformer procedure takes a syntax object and mode list and
returns a syntax object.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._provide-transformer~3f))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-transformer~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">provide-transformer?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> has the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:provide-transformer</a></span> property, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._provide-pre-transformer~3f))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._provide-pre-transformer~3f%29%29" class="RktValDef RktValLink" data-pltdoc="x">provide-pre-transformer?</a></span></span><span class="hspace"> </span><span class="RktVar">v</span><span class="RktPn">)</span><span class="hspace"> </span>→<span class="hspace"> </span><span class="RktSym"><a href="booleans.html#%28def._%28%28quote._~23~25kernel%29._boolean~3f%29%29" class="RktValLink" data-pltdoc="x">boolean?</a></span></p></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">v</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr></table></blockquote></div><div class="SIntrapara">Returns <span class="RktVal">#t</span> if <span class="RktVar">v</span> has the
<span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._prop~3aprovide-pre-transformer%29%29" class="RktValLink" data-pltdoc="x">prop:provide-pre-transformer</a></span> property, <span class="RktVal">#f</span> otherwise.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>struct</p></div></div><table cellspacing="0" cellpadding="0" class="RForeground"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="define-struct.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._struct%29%29" class="RktStxLink" data-pltdoc="x">struct</a></span></td><td><span class="hspace"> </span></td><td><a name="(def._((lib._racket/provide-transform..rkt)._export-orig-stx))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export-protect~3f))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export-mode))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export-out-sym))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export-local-id))"></a><a name="(def._((lib._racket/provide-transform..rkt)._make-export))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export~3f))"></a><a name="(def._((lib._racket/provide-transform..rkt)._struct~3aexport))"></a><a name="(def._((lib._racket/provide-transform..rkt)._export))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._export%29%29" class="RktValDef RktValLink" data-pltdoc="x">export</a></span></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym">local-id</span><span class="stt"> </span><span class="RktSym">out-sym</span><span class="stt"> </span><span class="RktSym">mode</span><span class="stt"> </span><span class="RktSym">protect?</span><span class="stt"> </span><span class="RktSym">orig-stx</span><span class="RktPn">)</span></td></tr></table></blockquote></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">#:extra-constructor-name</span><span class="hspace"> </span><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._make-export%29%29" class="RktValLink" data-pltdoc="x">make-export</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">local-id</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">out-sym</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="symbols.html#%28def._%28%28quote._~23~25kernel%29._symbol~3f%29%29" class="RktValLink" data-pltdoc="x">symbol?</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">mode</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="number-types.html#%28def._%28%28quote._~23~25kernel%29._exact-integer~3f%29%29" class="RktValLink" data-pltdoc="x">exact-integer?</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">protect?</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._any%2Fc%29%29" class="RktValLink" data-pltdoc="x">any/c</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">orig-stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></blockquote></div><div class="SIntrapara">A structure representing a single imported identifier:</div></p><ul><li><p><span class="RktSym">local-id</span> —<wbr></wbr> the identifier that is bound within the
exporting module.</p></li><li><p><span class="RktSym">out-sym</span> —<wbr></wbr> the external name of the binding.</p></li><li><p><span class="RktSym">orig-stx</span> —<wbr></wbr> a <a href="syntax-model.html#%28tech._syntax._object%29" class="techoutside" data-pltdoc="x"><span class="techinside">syntax object</span></a> for the source of
the export, used for error reporting.</p></li><li><p><span class="RktSym">protect?</span> —<wbr></wbr> indicates whether the identifier should
be protected (see <a href="modprotect.html" data-pltdoc="x">Code Inspectors</a>).</p></li><li><p><span class="RktSym">mode</span> —<wbr></wbr> the <a href="syntax-model.html#%28tech._phase._level%29" class="techoutside" data-pltdoc="x"><span class="techinside">phase level</span></a> of the binding in the
exporting module.</p></li></ul><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/provide-transform..rkt)._syntax-local-provide-certifier))"></a><span title="Provided from: racket/provide-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fprovide-transform..rkt%29._syntax-local-provide-certifier%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-local-provide-certifier</a></span></span><span class="RktPn"></span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span></a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">. </span><span class="RktSym"><a href="function-contracts.html#%28form._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._-~3e%2A%29%29" class="RktStxLink" data-pltdoc="x"><span class="nobreak">-></span>*</a></span><span class="RktPn"> .</span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">For backward compatibility only; returns a procedure that returns its
first argument.</div></p><h5 x-source-module="(lib "scribblings/reference/reference.scrbl")" x-source-pkg="racket-doc" x-part-tag=""keyword-trans"">12.4.3<tt> </tt><a name="(part._keyword-trans)"></a><a name="(mod-path._racket/keyword-transform)"></a>Keyword-Argument Conversion Introspection</h5><p><div class="SIntrapara"><table cellspacing="0" cellpadding="0" class="defmodule"><tr><td align="left"><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="require.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._require%29%29" class="RktStxLink" data-pltdoc="x">require</a></span><span class="stt"> </span><a href="#%28mod-path._racket%2Fkeyword-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/keyword-transform</span></a><span class="RktPn">)</span></td><td align="right"><span class="RpackageSpec"><span class="Smaller"> package:</span> <span class="stt">base</span></span></td></tr></table></div><div class="SIntrapara">The bindings documented in this section are provided by the <a href="#%28mod-path._racket%2Fkeyword-transform%29" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/keyword-transform</span></a> library, not <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket/base</span></a> or <a href="index.html" class="RktModLink" data-pltdoc="x"><span class="RktSym">racket</span></a>.</div></p><p><div class="SIntrapara"><blockquote class="SVInsetFlow"><table cellspacing="0" cellpadding="0" class="boxed RBoxed"><tr><td><table cellspacing="0" cellpadding="0" class="together"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/keyword-transform..rkt)._syntax-procedure-alias-property))"></a><span title="Provided from: racket/keyword-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fkeyword-transform..rkt%29._syntax-procedure-alias-property%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-procedure-alias-property</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._letrec%29%29" class="RktStxLink" data-pltdoc="x">letrec</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">val?</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="contract-utilities.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fbase..rkt%29._recursive-contract%29%29" class="RktStxLink" data-pltdoc="x">recursive-contract</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktSym">val?</span><span class="hspace"> </span><span class="RktSym">val?</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">val?</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="together"><tr><td><blockquote class="SubFlow"><div class="RBackgroundLabel SIEHidden"><div class="RBackgroundLabelInner"><p>procedure</p></div></div><p class="RForeground"><span class="RktPn">(</span><a name="(def._((lib._racket/keyword-transform..rkt)._syntax-procedure-converted-arguments-property))"></a><span title="Provided from: racket/keyword-transform | Package: base"><span class="RktSym"><a href="#%28def._%28%28lib._racket%2Fkeyword-transform..rkt%29._syntax-procedure-converted-arguments-property%29%29" class="RktValDef RktValLink" data-pltdoc="x">syntax-procedure-converted-arguments-property</a></span></span><span class="hspace"> </span><span class="RktVar">stx</span><span class="RktPn">)</span></p></blockquote></td></tr><tr><td><table cellspacing="0" cellpadding="0" class="prototype"><tr><td valign="top"><span class="hspace"> </span></td><td valign="top">→</td><td valign="top"><span class="hspace"> </span></td><td valign="top"><table cellspacing="0" cellpadding="0" class="RktBlk"><tr><td><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktVal">#f</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="let.html#%28form._%28%28lib._racket%2Fprivate%2Fletstx-scheme..rkt%29._letrec%29%29" class="RktStxLink" data-pltdoc="x">letrec</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktPn">[</span><span class="RktSym">val?</span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="contract-utilities.html#%28form._%28%28lib._racket%2Fcontract%2Fprivate%2Fbase..rkt%29._recursive-contract%29%29" class="RktStxLink" data-pltdoc="x">recursive-contract</a></span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fbase..rkt%29._or%2Fc%29%29" class="RktValLink" data-pltdoc="x">or/c</a></span><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28lib._racket%2Fprivate%2Fstx..rkt%29._identifier~3f%29%29" class="RktValLink" data-pltdoc="x">identifier?</a></span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktPn">(</span><span class="RktSym"><a href="data-structure-contracts.html#%28def._%28%28lib._racket%2Fcontract%2Fprivate%2Fmisc..rkt%29._cons%2Fc%29%29" class="RktValLink" data-pltdoc="x">cons/c</a></span><span class="hspace"> </span><span class="RktSym">val?</span><span class="hspace"> </span><span class="RktSym">val?</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">)</span><span class="RktPn">]</span><span class="RktPn">)</span></td></tr><tr><td><span class="hspace"> </span><span class="RktSym">val?</span><span class="RktPn">)</span><span class="RktPn">)</span></td></tr></table></td></tr></table></td></tr><tr><td><span class="hspace"> </span><span class="RktVar">stx</span><span class="hspace"> </span>:<span class="hspace"> </span><span class="RktSym"><a href="stxops.html#%28def._%28%28quote._~23~25kernel%29._syntax~3f%29%29" class="RktValLink" data-pltdoc="x">syntax?</a></span></td></tr></table></td></tr></table></blockquote></div><div class="SIntrapara">Reports the value of a syntax property that can be
attached to an identifier by the expansion of a keyword-application
form. See <span class="RktSym"><a href="lambda.html#%28form._%28%28lib._racket%2Fprivate%2Fbase..rkt%29._lambda%29%29" class="RktStxLink" data-pltdoc="x">lambda</a></span> for more
information about the property.</div></p><p>The property value is normally a pair consisting of the original
identifier and an identifier that appears in the
expansion. Property-value merging via <span class="RktSym"><a href="stxprops.html#%28def._%28%28quote._~23~25kernel%29._syntax-track-origin%29%29" class="RktValLink" data-pltdoc="x">syntax-track-origin</a></span> can make
the value a pair of such values, and so on.</p><div class="navsetbottom"><span class="navleft"><form class="searchform"><input class="searchbox" style="color: #888;" type="text" value="...search manuals..." title="Enter a search string to search the manuals" onkeypress="return DoSearchKey(event, this, "6.3", "../");" onfocus="this.style.color="black"; this.style.textAlign="left"; if (this.value == "...search manuals...") this.value="";" onblur="if (this.value.match(/^ *$/)) { this.style.color="#888"; this.style.textAlign="center"; this.value="...search manuals..."; }"/></form> <a href="../index.html" title="up to the documentation top" data-pltdoc="x" onclick="return GotoPLTRoot("6.3");">top</a></span><span class="navright"> <a href="stxcmp.html" title="backward to "12.3 Syntax Object Bindings"" data-pltdoc="x">← prev</a> <a href="Macros.html" title="up to "12 Macros"" data-pltdoc="x">up</a> <a href="stxparam.html" title="forward to "12.5 Syntax Parameters"" data-pltdoc="x">next →</a></span> </div></div></div><div id="contextindicator"> </div></body></html>
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