Re: negative regex without !~

~~/(?:$RegexGoesHere(?!)|(?=))/~~

Ok, right. The previous construction was incorrect. I think using the experimental conditional test would work here since now the (?!) does not connect via backtracking to the (?=).

/(?((?:$RegexGoesHere))(?!)|(?=))/

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Re^2: negative regex without !~ by ysth (Canon) on Jul 22, 2004 at 22:26 UTC
Doesn't work. (?!) just makes it take the second alternative. People have proposed a FAIL HERE mechanism, but there isn't one now. The alternate way (much worse than hv's IMO) that you sometimes see is (IIRC) `/^(.(?!$regex))*\z/s`	[reply] [d/l]
Re^2: negative regex without !~ by hv (Prior) on Jul 22, 2004 at 22:12 UTC
Update: oops ~~Ooh yes, that's much cleaner than my attempt. (You don't need the '`(?=)`' in there, but it's probably clearer with than without.)~~ Hugo	[reply] [d/l]