Well, I take it back, and have updated my answers.

Perl does special-case  /$foo/g and  s/$foo/.../g to avoid re-compiling. It does not optimize changing the anchor like  /\G$foo/gc, which is the actual code from my module.

The testing I did at the time was based on performance, rather than specifically tracing whether the compilation got invoked. It could be that evaling a coderef with the expanded regex text still performs better than referencing a compiled regex, but but I don't really have time right now to go back and benchmark it.

In reply to Re^6: On the regex pattern variable to be inserted into another (which recompile???) by NERDVANA
in thread On the regex pattern variable to be inserted into another by Anonymous Monk

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