This regex should do what you want: ((?:3{4})+)

With the /e modifier you can simplify your program a bit: 

#!/usr/str/perl
use strict;
use warnings;

my $toTranslate =
"333333333333333333333333333333333333333333333333333333333333333333333
+333333333333333333333333333333333333333333333333233333333322333333333
+233333333333333333333333333333333323333333322333333332333333333";

1 while $toTranslate =~ s/((?:3{4})+)/"[" . length($1) . "]"/ge;

print $toTranslate,"\n";

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In reply to Re: Regex exact pattern match problem! by moritz
in thread Regex exact pattern match problem! by Jts

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