Re: [Haskell-cafe] regex-applicative library needs your help! (algorithmic challenge)

I wrote regex-tdfa, the efficient (though not yet lightning fast) Posix-like engine. You are not the first to want an efficient Perl-like engine. The answer you seek flows from Russ Cox (though in C++):

http://google-opensource.blogspot.com/2010/03/re2-principled-approach-to-reg...

http://code.google.com/p/re2/

Quoting relevant bit:

It also finds the leftmost-first match, the same match that Perl would, and can return submatch information. The one significant exception is that RE2 drops support for backreferences¹ and generalized zero-width assertions, because they cannot be implemented efficiently.

On 13/09/2011 06:40, Roman Cheplyaka wrote:

Please help make the regex-based parsing library efficient!

https://github.com/feuerbach/regex-applicative/wiki/Call-For-Help