/usr/share/common-lisp/source/ is in cl-alexandria 0.0.20130703-1.
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/usr/share/common-lisp/source/alexandria/
/usr/share/common-lisp/source/alexandria/alexandria-tests.asd
/usr/share/common-lisp/source/alexandria/alexandria.asd
/usr/share/common-lisp/source/alexandria/arrays.lisp
/usr/share/common-lisp/source/alexandria/binding.lisp
/usr/share/common-lisp/source/alexandria/conditions.lisp
/usr/share/common-lisp/source/alexandria/control-flow.lisp
/usr/share/common-lisp/source/alexandria/definitions.lisp
/usr/share/common-lisp/source/alexandria/features.lisp
/usr/share/common-lisp/source/alexandria/functions.lisp
/usr/share/common-lisp/source/alexandria/hash-tables.lisp
/usr/share/common-lisp/source/alexandria/io.lisp
/usr/share/common-lisp/source/alexandria/lists.lisp
/usr/share/common-lisp/source/alexandria/macros.lisp
/usr/share/common-lisp/source/alexandria/numbers.lisp
/usr/share/common-lisp/source/alexandria/package.lisp
/usr/share/common-lisp/source/alexandria/sequences.lisp
/usr/share/common-lisp/source/alexandria/strings.lisp
/usr/share/common-lisp/source/alexandria/symbols.lisp
/usr/share/common-lisp/source/alexandria/tests.lisp
/usr/share/common-lisp/source/alexandria/types.lisp