Re: FAQ 4.58 How can I know how many entries are in a hash?

On Thu, 13 Dec 2007 05:01:22 -0800, Todd wrote:

$num_keys = keys %hash;

Seems there is a better way to do it:

#! /bin/perl -l

%hash = (a=>1, b=>2, c=>3, d=>4, e);
$num_keys = %hash+0;

I fail to see how this qualifies as "better".

[..]

So it means when in numeric(not string) context, %hash return numbers of
keys accidently. But anyway, it's a good feature.

This is indeed accidental, and as far as I know not guaranteed to work in
any future version of perl. It's also unlikely to work with tied hashes.

Joost.




.

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