Hi Monks,
Following piece of code is not work as obvios 
use strict;

my %hash = (
    'key01' => '1', 
    'key02' => '2',
    'key03' => '3',
);

my $key = 'key01';
if ($key in keys(%hash)) { ### 
    print "$key is in hash";
}

[download]
But my question is what is the optimal way to implement the functionality of "in" at "### in the above code (without looping entire array.

Thanks in advance - SB.

In reply to Best way check key availability by banduwgs

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