This contains two modules, regexp::list and regexp::optimizer.

regexp::list offers a method which turns a list of words into an optimized regular expression which matches all words therein. the optimized regular expression is much more efficient than a simple-minded '|'-concatenation.

regexp:optimizer factors out common suffices/prefices in regular expressions (trie optimization). currently, the user has to optimize "foo|far" and "foo|goo" into "f(?:oo|ar)" and "[fg]oo" by hand; this module does it automatically.