Is there a regular expression to detect a valid regular expression?

Re:Is there a regular expression to detect a valid regular e... by kyberias on Sunday September 08, 2019 @09:36AM (#20910489)

I hate it how the accepted answer is incorrect and does not teach the fundamental property of regular expressions.

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Re:Is there a regular expression to detect a valid regular e... by PeterisP on Sunday September 08, 2019 @10:35AM (#20910804)

The fundamental property of regular expressions is that the programming/software engineering concept of "regex" or "regular expression" is fundamentally different from the mathematical concept of "regular language".

If you see "regex" without any special context and start thinking about what it can/can't do, then the first association should be with something like PCRE and its capabilities, not something that's bound by the pumping lemma.

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Re:Is there a regular expression to detect a valid regular e... by unlinkr on Sunday September 08, 2019 @10:01AM (#20910598)

It only works in practice, not in theory.

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Re:Is there a regular expression to detect a valid regular e... by yifanl on Monday September 09, 2019 @08:34AM (#20917503)

It doesnt work in practice, PCRE does not validate all valid PCRE expressions.

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