[chavo-b]

why the resulting regex contains ++ instead of only one + ? such regexs are wrong!

[logn]

"Possessive quantifiers are a way to prevent the regex engine from trying all permutations. This is primarily useful for performance reasons. You can also use possessive quantifiers to eliminate certain matches."

http://www.regular-expressions.info/possessive.html

[chavo-b]

ok, tnx, now it makes sense