#!/opt/perl/bin/perl -w

use strict;

use Tie::Hash;
 
package Hash::Add;
 
@Hash::Add::ISA = qw /Tie::StdHash/;
 
 
use overload '+' => sub { 
    my ($self, $other) = @_;
 
    foreach my $key (keys %$self) {
        $self -> {$key} += $other -> {$key};                 
    }
};

package main;
 
my $totals = tie my %totals => 'Hash::Add';
my $delta  = tie my %delta  => 'Hash::Add';

my @fields = qw /foo bar/;
 
@totals {@fields} = (10, 20);
@delta  {@fields} =  (5,  6);

$totals += $delta;
 
print "Foo = $totals{foo}\n";
print "Bar = $totals{bar}\n";

__END__
Foo = 15
Bar = 26

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-- Abigail

In reply to Re: Using += in array context by Abigail
in thread Using += in array context by grinder

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