note
farang
<p>I think this has to do with optimization of the regexp. I may not be using terminology quite right, but Perl sees that the $sub variable can be interpolated, so the regexp is eval'd at compile time, thereby populating ${^MATCH}. That is, it is only after being eval'd once that ${^MATCH} gets the value from the search.<br><br>The following code also forces a similar 'second eval'.
<c>
my $x = "abcde";
$x =~ s/b../sprintf "==${^MATCH}=="/pe;
print "$x\n";
</c>
</p>
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