I'm not sure if this is a solution you will want to use but here is what I usually do. Instead of 
if ($USER{coffee} > 5){ ... }

[download]
I would use 
if (defined($USER{coffee}) && $USER{coffee} > 5) { ... }

[download]
I feel checking defindedness is good thing to do in any case.

In reply to Re: -w in production environment by Anonymous Monk
in thread -w in production environment by gwhite

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