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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
<HTML
><HEAD
><TITLE
>Introduction</TITLE
><META
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CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
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><BODY
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><TH
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>The Hugs 98 User's Guide</TH
></TR
><TR
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><HR
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WIDTH="100%"></DIV
><DIV
CLASS="CHAPTER"
><H1
><A
NAME="INTRODUCTION"
></A
>Chapter 1. Introduction</H1
><P
>In September 1991, Mark Jones released a functional programming system called
<I
CLASS="FIRSTTERM"
>Gofer</I
>, which provided a compact, portable implementation
of a Haskell-like language.
The system also included experimental type system extensions,
many of which later became part of Haskell.
On Valentine's Day 1995, Mark released
<I
CLASS="FIRSTTERM"
>Hugs</I
> (Haskell User's Gofer System),
a derivative of Gofer with greater Haskell compliance.
Hugs versions are named after the version of Haskell they support;
Hugs 98 was released in January 1999.
Mark gave up the maintainership of Hugs in January 2000.</P
><P
>Hugs 98 still aims to be a fairly lightweight, portable implementation,
and now adheres closely to Haskell 98.
It also supports several extensions shared with other Haskell implementations:
<P
></P
><UL
><LI
><P
>Hugs supports standardized extensions (addenda) to Haskell 98,
for interfacing to foreign languages and structuring the module space.</P
></LI
><LI
><P
>With the appropriate options (see <A
HREF="options.html#OPTIONS-LANGUAGE"
>Section 3.1.1</A
>),
it is also possible to turn on a number of language extensions,
most of which are also supported by the
<A
HREF="http://www.haskell.org/ghc/"
TARGET="_top"
>Glasgow Haskell Compiler</A
> (GHC),
though some are specific to Hugs.</P
></LI
><LI
><P
>Hugs comes with a large collection of libraries,
also shared with other Haskell implementations,
and described in <A
HREF="http://www.haskell.org/ghc/docs/latest/html/libraries/"
TARGET="_top"
>separate documentation</A
>.</P
></LI
></UL
>
Though these features make Hugs highly compatible with other implementations,
it is primarily intended as interpreter and programming environment
for developing Haskell programs.
If your application involves large programs or speed is critical,
you may strike Hugs's limitations, and may wish to try a Haskell compiler.</P
><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="OTHER"
>1.1. Other sources of information</A
></H1
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="OTHER-DOCUMENTATION"
>1.1.1. Other documentation</A
></H2
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><A
NAME="USER-MANUAL"
></A
><I
CLASS="CITETITLE"
>The Hugs 98 User Manual</I
></DT
><DD
><P
>This was the definitive reference for earlier versions of Hugs,
though parts of it are now out-of-date.
Much of it remains relevant, particularly Section 7 on Hugs extensions,
and it should be consulted in several areas that this Guide does not cover well.
The manual is available in several formats:
<A
HREF="http://cvs.haskell.org/Hugs/pages/hugsman/index.html"
TARGET="_top"
>HTML</A
>,
<A
HREF="http://cvs.haskell.org/Hugs/downloads/hugs.pdf"
TARGET="_top"
>PDF</A
>,
<A
HREF="http://cvs.haskell.org/Hugs/downloads/hugs.ps.gz"
TARGET="_top"
>gzipped Postscript</A
>,
<A
HREF="http://cvs.haskell.org/Hugs/downloads/html.tar.gz"
TARGET="_top"
>gzipped tar-ed html</A
>,
<A
HREF="http://cvs.haskell.org/Hugs/downloads/hugs.dvi"
TARGET="_top"
>dvi</A
>,
<A
HREF="http://cvs.haskell.org/Hugs/downloads/hugs-hlp.zip"
TARGET="_top"
>WinHelp(zipped)</A
> and
<A
HREF="http://www.galois.com/~sof/hugs98.chm"
TARGET="_top"
>HTMLHelp(win32 help format)</A
>.</P
></DD
><DT
><A
NAME="HASKELL98-REPORT"
></A
><I
CLASS="CITETITLE"
>Haskell 98 Language and Libraries: the Revised Report</I
></DT
><DD
><P
>The definitive reference for the Haskell 98 language and standard libraries,
published by Cambridge University Press, and also available
<A
HREF="http://www.haskell.org/definition/"
TARGET="_top"
>online</A
>.</P
></DD
><DT
><A
NAME="LIBRARIES"
></A
><A
HREF="http://www.haskell.org/ghc/docs/latest/html/libraries/"
TARGET="_top"
>Haskell Hierarchical Libraries</A
></DT
><DD
><P
>A collection of libraries shared by Haskell implementations, including Hugs.</P
></DD
><DT
><A
HREF="http://www.cs.nott.ac.uk/Department/Staff/mpj/faq.html"
TARGET="_top"
>comp.lang.functional FAQ</A
></DT
><DD
><P
>General information about functional programming.</P
></DD
></DL
></DIV
><P
>More information about Haskell may be found on the
<A
HREF="http://www.haskell.org/"
TARGET="_top"
>Haskell home page</A
>
and the <A
HREF="http://www.haskell.org/hugs/"
TARGET="_top"
>Hugs home page</A
>.</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="MAILING-LISTS"
>1.1.2. Mailing lists</A
></H2
><P
>There are a number of mailing lists where people discuss Hugs and Haskell,
all with archives of past postings:</P
><P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><A
HREF="http://www.haskell.org/mailman/listinfo/hugs-users"
TARGET="_top"
>hugs-users</A
></DT
><DD
><P
>This is the place for general discussion about using Hugs.</P
></DD
><DT
><A
HREF="http://www.haskell.org/mailman/listinfo/hugs-bugs"
TARGET="_top"
>hugs-bugs</A
></DT
><DD
><P
>Use this list for reporting bugs.
This is more likely to be effective than direct mail to the authors
or maintainers of Hugs.
We do read this mailing list &ndash; but so do many other people,
who might be able to give you more appropriate or timely advice than us!
Before reporting a bug, check the list of known deviations from Haskell 98
(see <A
HREF="haskell98.html#BUGS-HASKELL98"
>Section 5.1</A
>).</P
></DD
><DT
><A
HREF="http://www.haskell.org/mailman/listinfo/cvs-hugs"
TARGET="_top"
>cvs-hugs</A
></DT
><DD
><P
>Discussion of the development of Hugs takes place on this list.
This list also receives commit messages from the
<A
HREF="http://cvs.haskell.org/cgi-bin/cvsweb.cgi/hugs98/"
TARGET="_top"
>Hugs CVS repository</A
>.</P
></DD
><DT
><A
HREF="http://www.haskell.org/mailman/listinfo/haskell-cafe"
TARGET="_top"
>haskell-cafe</A
></DT
><DD
><P
>An informal list for chatting about Haskell.
This is an ideal place for beginners to get help with Haskell,
but Hugs-specific questions would be better directed at the Hugs lists.</P
></DD
><DT
><A
HREF="http://www.haskell.org/mailman/listinfo/haskell"
TARGET="_top"
>haskell</A
></DT
><DD
><P
>A lower-volume list for more technical discussion of Haskell.
Please do not post beginner questions or Hugs-specific questions to this list.</P
></DD
></DL
></DIV
><P
>There are several other Haskell-related mailing lists served by
<SPAN
CLASS="SYSTEMITEM"
>www.haskell.org</SPAN
>.
See <A
HREF="http://www.haskell.org/mailman/listinfo/"
TARGET="_top"
><TT
CLASS="LITERAL"
>http://www.haskell.org/mailman/listinfo/</TT
></A
>
for the full list.</P
><P
>Some Haskell-related discussion also takes place in the Usenet newsgroup
<A
HREF="news:comp.lang.functional"
TARGET="_top"
><SPAN
CLASS="SYSTEMITEM"
>comp.lang.functional</SPAN
></A
>.</P
></DIV
></DIV
></DIV
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