Another approach to delayed evaluation is to use closures (update: ok, not really closures, but subroutines). To get a sub to be evaluated in the double-quotish context of a s/// replacement, it needs to be part of a block. The only block interpolated in double quotes is a deref.

So you make the closure return a ref to the string you want, and deref it in the replacement. It will be evaluated at replacement time, and you get the substitution you're looking for. 

my $regex = ['(foo)',sub {\"bar$1"}];
my $string = 'blah foo blah';
$string =~ s/$regex->[0]/${$regex->[1]->()}/;
print "S=$string\n";

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In reply to Re: Regex Substitution, Interpolating on the RHS? by Roy Johnson
in thread Regex Substitution, Interpolating on the RHS? by Cody Pendant

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