If you can compile your regex into DFA, you will be able to tell (trivially). However, perl regex have backreferences, can embed code, and so on. Basically the Halting Problem? In that case, the answer is no.

In reply to Re: Can I determine index point of failure in string during regex match attempt by oiskuu
in thread Can I determine index point of failure in string during regex match attempt by tj_thompson

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