I have a code snippet that's generating odd errors. Can you tell what I've done wrong? 
print "$tmpf\n";   # prints 'farms'
print keys( %factories);   # 'farms' is one of them.
if ( defined $factories{ $tmpf})

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This seems to do what I want, but it also generates the error message 'Use of uninitialized value in pattern match (m//)'

In reply to Why? uninitialized value in pattern match when using if (defined) by Dervish

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