grep is your friend! :

use strict;
use warnings;

my @array=({key1=>1,key2=>2},{key1=>1,key2=>3},{key1=>1,key2=>5});
print "Yes!\n" unless grep { $_->{key1} != 1 } @array;

[download]

Or, if the array is large, List::Util's first is even a better friend:

#!/usr/bin/perl
use strict;
use warnings;
use List::Util qw( first );

my @array=({key1=>1,key2=>2},{key1=>1,key2=>3},{key1=>1,key2=>5});
print "Yes!\n" unless first { $_->{key1} != 1 } @array;

[download]

Update: Ok, I agree with holli, grep and (probably) first are loops, but not explicit loops, that was what maybe he was asking for. When I think in loops, I think in for, while and friends, and I see map, grep... more as "list transformers".

In reply to Re: Checking if all the key values are same in an Array by deibyz
in thread Checking if all the key values are same in an Array by perl_devel

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