#!/usr/local/bin/perl

use strict;
use warnings;

package MyData;

sub getData {

    my $data = {
        'test'  => 'yes',
        'key'   => 'value',
        'some'  => 'thing',
        'array' => [ 1, 2, 3 ],
    };

    my $key = shift;

    defined $data->{$key}
      ? return $data->{$key}
      : return;
}

package main;

foreach my $testcase (qw(test key some bork)) {
    my $value = MyData::getData($testcase);

    if ($value) {
        print "Data for $testcase : $value \n";
    } else {
        print "No such data : $testcase .\n";
    }

}