Then maybe you want 3-value-logic ?

http://blogs.perl.org/users/ovid/2013/02/three-value-logic-in-perl.html

http://en.wikipedia.org/wiki/Three-valued_logic

In reply to Re^3: Do people find warning for undef with string compare useful? by vsespb
in thread Do people find warning for undef with string compare useful? by perl-diddler

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