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

Re:Is there a regular expression to detect a valid regular e... by hk__2 on Sunday September 08, 2019 @03:05PM (#20912658)

What about <a>this  </a> ?

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Re:Is there a regular expression to detect a valid regular e... by unlinkr on Monday September 09, 2019 @01:56AM (#20915540)

Yes you can tokenize this with a regular expression and extract the valid start and end tags.

If comments in XHTML could nest you would have a problem. But this is not the case.

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Re:Is there a regular expression to detect a valid regular e... by hk__2 on Monday September 09, 2019 @03:53AM (#20916055)

> Yes you can tokenize this with a regular expression and extract the valid start and end tags.

So you need more than a regular expression, hence your premise is incorrect.

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Re:Is there a regular expression to detect a valid regular e... by unlinkr on Monday September 09, 2019 @04:52AM (#20916334)

No, you don't need more than a regular expression. If you want to extract elements, i.e. match start tags to the corresponding end tags, then you need a stack-based parser. But just to extract the start tags (which is the question) a regular expression is sufficient.

The original question is a question about tokenization, not parsing, which is why a regular expression is sufficient.

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