You can always get at the first key and the first value of a hash by looking at the hash as a list:

my ($key,$value) = %hash;
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If your hash has more than one key, you will get a key, but as a hash is not ordered, there is no guarantee that you will get a specific key.

Or slice it out:

  my $key = (keys %hash)[0];

• another intruder with the mooring in the heart of the Perl

my ($a_key) = keys %$myHas;


foreach my $l (keys %$myHas) {
    ....
    last;
}


while (my ($a_key) = each %$myHas) {
    ....
    last;
}
keys %$myHas;  # Reset iterator.
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You can always use grep if you know what the name will be like:

use strict;
use warnings;
use Data::Dumper;

my %hash = (
    foo       => 'bar',
    football  => 'Monday',
    one_thing => 'another',
);

my @match = grep /^foo/, keys %hash;
print Dumper \@match;
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L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

If there's one key in the hash, keys(%hash) will return a single element array (excuse me, I've gone into lecture mode...).

If you really don't care about which key you get from a hash with more than one entry, wouldn't

($key) = keys(%hash);
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be perfectly adequate?

Incidentally, if there is going to be only one key in a hash or, if you've multiple keys and don't care which one you get, why are you using a hash?

Thanks to Perl Mouse for pointing out a horrid error on my part; for some inane reason I thought shift(keys(%hash)) was valid Perl.

wouldn't

$key = shift(keys(%hash));
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be perfectly adequate?

How could something that doesn't even have a remote chance of compiling be "perfectly adequate"?

shift, but it's nature, must have an lvalue as its argument, and to be more precise, an lvalue that starts with an @. List context keys() is neither. shift isn't an alternative for [0].

Perl --((8:>*

Because I went into idiot mode; it tends to happen often on Mondays.

emc