Good point. As long as it's the only clause in the regex, you're right that they'd be equivalent.

But to issue the warning you want, the regex engine would have to post-process the regex, to make sure it IS equivalent, and no one slipped in anything after the closing ).

And even then, how would you deal with qr//?

Given: 

$re=qr/(LIST|OF|LISTS)/;

[download]
you couldn't optimize $re to /(LIST|OF)/, since you don't know where it will be used, right?

Mike

In reply to Re: Superfluous subpatterns in regex alternations. by RMGir
in thread Superfluous subpatterns in regex alternations. by demerphq

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