The above condition is not equivalent to what you posted earlier. 

NOT( DEFINED(A) AND DEFINED(B) AND DEFINED(C) ... )

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is equivalent to: 
( NOT DEFINED(A) ) OR ( NOT DEFINED(B) ) OR ( NOT DEFINED(C) ) ...

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That's De Morgan's theorem.


TGI says moo

In reply to Re^2: if not defined by TGI
in thread if not defined by Trihedralguy

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