You can also store the matching parts in an array in a (?{}) expression: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

for my $string (qw( ab1b2b3d
                    ab1b2x
              )) {
    my @two;
    my @matches = $string =~ /(a)
                              (b.(?{ push @two, $2 if defined $2 }))+
                              (d)/x;
    say for @matches, '---', @two, '======';
}

[download]

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re^3: Regex troubles... by choroba
in thread Regex troubles... by kepler

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