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Problem is that every framework have their own dialect of it, and many of them are not even regular expression, but something beyond that.
by hvidgaard 10y ago
Problem is that every framework have their own dialect of it, and many of them are not even regular expression, but something beyond that.
- thedufer 10y agoThe most common dialect is PCRE. Most languages have an implementation of either that or a superset of it.
- hvidgaard 10y agoThe most common dialect is PCRE. Most languages have an implementation of either that or a superset of it. PCRE isn't exactly simple to begin with. That languages may implement it, or a superset of it, is exactly the problem. I know regular expressions very well, or rather I know regular languages and can fairly easily identify if a problem is solvable as a regular expressions. But once you start to go beyond that, it's not simple anymore and the benefit of a regular expression is lost.
- thedufer 10y agoIf you know what . does, various repetition markers (*,+,?,{}), and character classes, you're 90% there. Back-references are another big portion, although that's admittedly where things start getting a bit complex.