No need to execute any code inside a regular expression to solve your problem: 

use strict;
use warnings;
use 5.010; # only required for say()

$_ ='abacdbccdee';
if (/(?:[^bc]*[bc]){3}/g) {
    say pos;
}

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Perl 6 - second systems done right

In reply to Re: a regular expression problem by moritz
in thread a regular expression problem by siskos1

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