Re^3: search for 'cat' not followed by 'dog'

Old habit that I write in a non-capture when I'm doing grouping. In this case, after some *quick* testing, I realize that the negative lookahead doesn't appear to capture by default. In fact, even with benchmarking, the non-cap is effectively no more efficient than leaving it out.

Comment on Re^3: search for 'cat' not followed by 'dog'

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Re^4: search for 'cat' not followed by 'dog' by haukex (Archbishop) on Jan 29, 2019 at 08:57 UTC
Note that even if the lookarounds did capture, putting a non-capturing group around a capturing group doesn't stop it from capturing, i.e. `"x"=~/(?:(x))/` still puts `"x"` in `$1` (you can even do funky stuff like `"xyz"=~/(?=(y))/` which will capture `"y"` without advancing the match position past it). As of 5.22 you can say `(?n:...)` and any capture groups inside will be non-capturing.	[reply] [d/l] [select]