If you want to match the date 04/30/2010 then neither \d{2}\/\d{2}\/\d{4} nor \S+ is correct. Both will match ٦٦/٦٦/٦٦٦٦, or 98/76/5432 for that matter. Neither of them is actually 04/30/2010. If you just don't care about false positives, returning 1 instead of doing a match is the fastest way.

In general, being as precise as possible is the fastest, as that allows Perl to fail early. Always remember that when benchmarking matching: benchmark failures as well. But that's the general cause. There will be endless examples and cases with additional assumptions where vagueness wins. But those will be exceptions.

In reply to Re: Regex: is it faster to be vague? by JavaFan
in thread Regex: is it faster to be vague? by cmm7825

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