Perhaps you mean succinct rather than efficient?

use 5.010;

...

$hash{$key} //= 0;

[download]

is succinct, clear (if you know the syntax) and likely about as efficient in terms of fewest processor cycles as you can get. It requires Perl 5.10, but that shouldn't be a problem most places now.

True laziness is hard work

In reply to Re: Perl Hash Behavior. by GrandFather
in thread Perl Hash Behavior. by Anonymous Monk

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