Namely: For a given A != B, (!A or !B) == !(A && B), which will always be true for any single value.

ow.

You attached two conditions to (!A or !B) == !(A && B), but it's always true.

You refer some non-existent "single value" because you meant to talk about (V != A) or (V != B).

I believe you meant: 

(A or B)

[download]
is equivalent to 
!(!A and !B)

[download]
Because of that, 
(V != A) or (V != B)

[download]
is equivalent to 
!( (V == A) and (V == B) )

[download]

If A != B, the "and" is obviously false (since V can't have two different values at the same time), and the whole statement is therefore true.

In reply to Re^2: This is why Perl is so frustrating by ikegami
in thread This is why Perl is so frustrating by eggmatters

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