irregex
                               -------

               Portable Efficient IrRegular Expressions

                 http://synthcode.com/scheme/irregex/

A fully portable and efficient R[4567]RS implementation of regular
expressions, supporting both POSIX syntax with various (irregular)
PCRE extensions, as well as SCSH's SRE syntax.  DFA matching is used
when possible, otherwise a closure-compiled NFA approach is used.

Documentation is in the file irregex.html.