#!/usr/bin/env perl

use Data::Dumper;
use strict;
use warnings;

my $_aref = [[1,1],2,[1,1]];

my $_s=''.Data::Dumper->Dump([\$_aref],[qw(*_aref)]);
substr($_s,0,10)='';
our ($w,$t)=(0,0);
my $_re=qr{
        (?:
           \s+       # blank space - ignore
          |[,]       # comma - ignore
          |\[        # [ - increase weight
              (?{ local $w=$w+1; print "++w: $w\n"; })
          |\]        # ] - decrease weight
              (?{ local $w=$w-1; print "--w: $w\n"; })
          |(\d+)       # value - multiply by weight and add to $t
              (?{ print "value: $1\n"; $t+=$w*$1; print "\$t=$t\n";  })
        )
         }x;
if ($_s=~ m{(?{local $w=0;})^$_re*$}gms) {
    print "$t";
     };

__END__