This library supports full W3C XML Schema regular expressions
inclusive all Unicode character sets and blocks. The complete grammar
can be found under http://www.w3.org/TR/xmlschema11-2/#regexs. It is
implemented by the technique of derivations of regular expressions.

The W3C syntax is extended to support not only union of regular sets,
but also intersection, set difference, exor. Matching of
subexpressions is also supported.

The library can be used for constricting lightweight scanners and
tokenizers. It is a standalone library, no external regex libraries
are used.

Homepage:
http://hackage.haskell.org/package/hxt-regex-xmlschema
