You haven't said what you understand by "null" in this context. "null" is not a concept in Perl. We have defined and we have true. eg:

ValueTrue?Defined?
undefNoNo
0NoYes
''NoYes
1YesYes
'TIMTOWTDI'YesYes

BTW, do you really find unless ! to be clearer than if?

In reply to Re: Checking Variable for Not Null by hippo
in thread Checking Variable for Not Null by dirtdog

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