Here. This is definitely NOT shorter, but it is more robust. And unless I'm clueless, using map in a situation like this creates a second array in RAM, which you are throwing away. While this may not be a problem, it does not promote efficient memory management. 
#!/usr/bin/perl -w
use strict;
my %hash = ( foo => '123' , bar => '234',
             batz => '345', bongo => '100' );

#send reference to hash, and list of keys to sum
print sum_hash( \%hash, 'foo', 'bar', 'batz' ) . "\n";

#send reference to hash, will sum all numeric values
print sum_hash( \%hash ) . "\n";

sub sum_hash {
    my $t_hash = shift;
    my $total;
    if (@_) {
        for (@_) {$total += $t_hash->{$_}; }
    }
    else {
        for ( keys %$hashref ) { $total += $t_hash->{$_}; };
    }
    return $total;
}

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In reply to Re: sum function by ichimunki
in thread sum function by Anonymous Monk

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