It's trivial for a few things, but quickly becomes larger than life. The question is how do we securely interpret an re with a large enough feature-set to be useful for most things. Looks like this may not be a concern and that's indeed an acceptable answer.

What do you mean by "securely", what is the security concern?

In reply to Re^5: Untaint a string match, regular expression. by Anonymous Monk
in thread Untaint a string match, regular expression. by cheako

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