It's not as bad as generating all combinations. Roughly speaking, the regex engine only needs to compare upper- and lower-case versions of the next character in the pattern, and it gets to move on as soon as it finds a match.

As you suggest, if speed matters it's best to apply lc to the searched text and use a lower-cased regex pattern.

After Compline,
Zaxo

In reply to Re: Slowness of /i by Zaxo
in thread Slowness of /i by sulfericacid

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