You can assign a list to a hash slice, but that's about it. You need another loop: 
my %add = ( a => 1,
            b => 2,
            c => 3,
          );
for (1 .. 10) {
    $totals{$_} += $add{$_} for keys %add;
}
print Dumper(\%totals);

[download]

Or, you use each: 

    while (my ($k, $v) = each %add) {
        $totals{$k} += $v;
    }

[download]
لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: += a hash slice? by choroba
in thread += a hash slice? by Random_Walk

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