find a number of keys in a hash

perlthirst has asked for the wisdom of the Perl Monks concerning the following question:

hi,

how to find a number of keys in a hash with out declaring temporary array?

I am able to get number of keys in a hash, by using the following method

use strict;
use warnings;


my %data= (
    'a' => 'b',
    'c' => 'd',
    'e' => 'f'
    );

my @keylen = keys %data;
print $#keylen;
[download]

But here I have used array named as keylen and then i got the total number of keys.

Is it possible to take in a step. Kindly advice.

Comment on find a number of keys in a hash Download Code

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Re: find a number of keys in a hash by setebos (Beadle) on Jan 16, 2009 at 14:25 UTC
`scalar(keys(%hash_name))`	[reply] [d/l]
Re: find a number of keys in a hash by Fletch (Bishop) on Jan 16, 2009 at 14:26 UTC
Actually you got 1 less than the number of keys because arrays are zero based, but that's a different problem. If you read the keys documentation the second sentence explains that calling it in scalar context returns the number of keys: `my $num_keys = keys %data`. The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l]
Re^2: find a number of keys in a hash by MidLifeXis (Monsignor) on Jan 16, 2009 at 19:35 UTC
Or the last index of the array (if you change `$[`) --MidLifeXis	[reply] [d/l]
Re: find a number of keys in a hash by jwkrahn (Abbot) on Jan 16, 2009 at 14:25 UTC
Using keys in scalar context will return the number of keys in the hash: `my $keylen = keys %data; print $keylen;` [download]	[reply] [d/l]