Regular expression for Regular expressions?

Posted by kavoir.com on Stack Overflow See other posts from Stack Overflow or by kavoir.com
Published on 2010-05-07T14:45:46Z Indexed on 2010/05/07 14:48 UTC
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php

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regular

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expression

I have an app that enables the user to input a regular expression, my question is how to check against any input of regular expressions and make sure they are valid ones because if they are not there will be preg_match errors.

I don't want to use the '@' before preg_match, so if there's a way to check the validity of the user input of regular expressions that'd be great.

The regular expression system of PHP seems to be rather too complicated for me to come up with a regular expression for them. Any idea or any alternatives would be possible in achieving this?

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