in reply to Regex troubles...

That's how repeated captures work. $2 indicates the match that starts at the second group, it can't populate $3 (maybe it should return an array reference?)

I'd solve this in two steps. In the first one, match the whole repetition, than split it into single expressions: 

my @source = $text =~ /(regex1)((?:regex2)+)(regex3)/g;
my @repeated = $source[1] =~ /.../g;  # or split or whatever

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($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,

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Re^2: Regex troubles...
by kepler (Scribe) on Apr 20, 2016 at 13:42 UTC
    Hi, Thank you very much for the solution - I've been programming in Perl for some years and I must confess that I wasn't aware of this important detail in regexs that you kindly provided. Kind regards, Kepler
[reply]
      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]
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        That doesn't seem to yield any output that I can understand. Why three 'b1' 'b2' 'b3' from ab1b2b3b4d and nothing from any of the others? 

        c:\@Work\Perl\monks>perl -e
"use warnings;
 use strict;
 use feature qw{ say };
 ;;
 for my $string (qw(ab1b2b3b4d  ab5b6b7d  ab8b9d  abxd  ad)) {
   my @two;
   my @matches = $string =~ /(a)
                             (b.(?{ push @two, $2 if defined $2 }))+
                             (d)/x;
   say for @matches, '---', @two, '======';
   }
"
a
b4
d
---
b1
b2
b3
======
a
b7
d
---
======
a
b9
d
---
======
a
bx
d
---
======
---
======

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        Update: "This is perl 5, version 14, subversion 4 (v5.14.4) built for MSWin32-x86-multi-thread"

        Give a man a fish:  <%-{-{-{-<

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