I guess it might have to do with the keys and values of %ENV being stringified, so perhaps that's why you're not seeing undef. A different criteria you could use might be $value = 'empty value' unless length $value;

In reply to Re^2: not able to make defined-or operator work in my code by Anonymous Monk
in thread RE: not able to make defined-or operator work in my code by lonewolf28

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