I haven't dipped my toe into this deeper end of the regex pool yet, so I'm curious about the motivation behind your question. If I understand it right, you want an expression, which you are placing within  (?{...}), to execute every time you evaluate this regex, regardless of whether or not the remainder of the regex yields an actual match.

If that is the correct understanding, why would you want to do it that way, as opposed to this way: 

   your_executable_expression;
   /XXX/

[download]
That is, since this expression should execute in any case, just go ahead and do it outside the regex, then evaluate the (simpler) regex.

If I have the wrong understanding, could someone explain what you get from  /(?{...}).../ (without the optimization, as requested here) that you wouldn't get from running that statement outside the regex? (I just don't know.)

In reply to Re: Disabling regexp optimizations? by graff
in thread Disabling regexp optimizations? by diotalevi

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