! Aware to Perl: How can I know how many entries are in a hash?

How can I know how many entries are in a hash?

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If you mean how many keys, then all you have to do is take the scalar sense of the keys() function:

    $num_keys = scalar keys %hash;

In void context it just resets the iterator, which is faster for tied hashes.

Source: Perl FAQ: Data Manipulation
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.

(Corrections, notes, and links courtesy of RocketAware.com)

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