For a regex intensive project many moons ago, I was running the same regex in loop against a big array of entries. I thought that this was the ideal place for the /o option, but I found that it made no performance difference at all. I remember reading somewhere that in some situations, Perl is smart enough to do /o automatically without being asked to do so. That appeared to be the case in my test. Its been so long ago, that I don't remember the exact regex being tested - could be that there wasn't a $var in it to begin with - don't remember.

In reply to Re^2: Regex /o modifier: what bugs? by Marshall
in thread Regex /o modifier: what bugs? by kcott

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