It is also a good practice to check for the existence of hash keys, particularly when prompting for input via the keyboard: 
if (exists $locs{$loc}) {
    # do something...
}
else {
   die "key $loc does not exist";
}

[download]

Update: I should have read mscharrer's node more closely, as this was already mentioned. But, I provided the link to the docs, so I guess this is not completely redundant.

In reply to Re: pulling value based on input by toolic
in thread pulling value based on input by kwn

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