Re^6: complaint: always testing defined()

But really, equality comparison of an undefined variable to anything else should just merrily produce the darned truth value without fuss.

Eww. That would be almost as bad as eq returning true, false, or undef (the latter if either operand is undef) ala SQL's NULL handling. I think the existing undef-becomes-""-or-0 is just fine.

Comment on Re^6: complaint: always testing defined()

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Re^7: complaint: always testing defined() by parv (Parson) on Nov 05, 2007 at 09:03 UTC
(In the proposed equality comparison of undef values) I would expect true only when both values are undef, false in any other case. That would result in much, w.r.t. Perl 5, POLA violation when warnings are off, namely `0 == undef` and `'' eq undef` both returning false of course. One third day later ... Near "POLA violation" added the warnings usage, and corrected the given comparison results (in Perl 5 without warnings, results are true values).	[reply] [d/l] [select]

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Re^7: complaint: always testing defined()
by parv (Parson) on Nov 05, 2007 at 09:03 UTC

(In the proposed equality comparison of undef values) I would expect true only when both values are undef, false in any other case. That would result in much, w.r.t. Perl 5, POLA violation when warnings are off, namely 0 == undef and '' eq undef both returning false of course.

One third day later ... Near "POLA violation" added the warnings usage, and corrected the given comparison results (in Perl 5 without warnings, results are true values).

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