If the regex is built from untrusted input, the consider these words from Nicholas Clark (talking about another issue):

So it's not going to be an issue at all, unless your programmers are foolish enough to allow untrusted user input to be interpolated into regular expressions. In which case, you were already open to denial of service attacks from patterns that bust the C stack (fixed by Dave for 5.10) or take until the heat death of the universe to complete (inherently unfixable in a general purpose programming language)

If the regex is built from trusted input, then use re 'eval'; won't hurt.

would like to know how to do it another way(thats stable).

Do what? You didn't say what it's suppose to do. There's not a single comment that hints as to what it's suppose to do. Yet we're suppose to figure out what you want from complex code that "has a few strange bugs in it".

In reply to Re: Regex (?{ code }) and use re 'eval' by ikegami
in thread Regex (?{ code }) and use re 'eval' by SFLEX

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