The performance penalty is still there. It is even more important in recent versions of perl as it prevents most optimisation from being performed. So by using it you loose a lot of the work that has been done to speed-up common regexps.

Which does not mean that it is a problem in most cases. When in doubdt use Benchmark!

In reply to Re: performance penalty using case insensitivity by mirod
in thread performance penalty using case insensitivity by filmo

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