#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my $data = '123 456 789 987 654 321';

my @results;
$data =~ /(\d+\s*(?{push @results, $1 if defined $1}))+$/;
push @results, $1;

print Dumper(@results);
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Just messing around seeing what could be done. not really sure why the last match doesn't get included or why the first one is undef, but i think they are probably related. Perhaps i'm actually pushing the last match not the current match, in fact thats almost certainly whats happening, anyone know how to reference the current match in a code block?