> The regexp package we currently use implements POSIX 1003.2 regexps
> (see src/backend/regex/re_format.7). I believe there is an item on the
> TODO list about upgrading the regexp parser to something more modern
> ... feel free to hop on that project if it's bugging you ...
I would like to recommend
ftp://ftp.cus.cam.ac.uk/pub/software/programs/pcre/
which stands for "PERL compatible regular expressions" and has an
expression analyzer & compiler for more efficient repeated matching.
Since Philip Hazel has only written this package to support his Mail
Transfer Agent (exim), it is optimised for performance.
I hope I have been of help,
Oliver Seidel
