While it is true that %hash{$_}++ is illegal syntax, it is interesting to note that %hash->{$_}++is not. (But it only works on actual hashes and not hash references.) AFAIK its a bug, but one that has basically become a feature. 
use Data::Dumper;
use strict;
use warnings;
my %hash;
%hash->{$_}=$_ foreach 0..5;
print Dumper(\%hash);
__END__
$VAR1 = {
          '0' => 0,
          '1' => 1,
          '2' => 2,
          '3' => 3,
          '4' => 4,
          '5' => 5
        };

[download]
It embarrassed the crap out of me when I discovered this. I was reviewing some code of my colleagues, (relatively new to perl at the time) and identified these as compile time errors. He politely told me what I was full of :-) and then showed me it compiled (and worked) fine. Luckily he had a few other subtle bugs that I found so I managed to avoid looking like a complete moron. :-)

--- demerphq
my friends call me, usually because I'm late....

In reply to Re: •Re: Re: Get All Duplicated Elements in an Array (Once, without shifting) by demerphq
in thread Get All Duplicated Elements in an Array (Once, without shifting) by George_Sherston

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