Why are the dollar signs doubled?

I would not expect the -xism part to cost anything over the (?: ) without that. Again, that makes me wonder if re-compiling the string is worse than incorporating a compiled regex in another qr. Naturally, being able to leave off the parens completely simplifies things.

The regex engine has improved its optimizations in successive versions of Perl too; I think I read something about that in either the 5.10 or 5.12 notes.

In reply to Re^4: Composing regex's dynamically by John M. Dlugosz
in thread Composing regex's dynamically by John M. Dlugosz

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