It just needs some repair for syntax problems:

#!/usr/bin/perl

$regex = qr/(?{print "Hey!";}).../;
$string = "some word";

$string =~ s/some($regex)/$1 x 5/e;
print $string,$/;

[download]
Your parens in $regex weren't closed. I added qr// because it's a good thing to do, and some dots to match and a substitution just to demonstrate.

Update: The 'quote regex' operator, qr//, precompiles the regex before storing it. That improves performance in the same way as m//o and s///o, but the result is stored rather than scoped as /o is. Precompilation gains nothing if the regex is only used once, but if the regex is to be stored in a variable anyway, it does no harm that I know of.

After Compline,
Zaxo

In reply to Re: RegEx Perl Code by Zaxo
in thread RegEx Perl Code by Jaspersan

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