Re^5: NaNs are true

What happens if you add NaN to zero? i.e.

if ( 0 + $MPFR_NaN_obj )
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I reckon we are the only monastery ever to have a dungeon stuffed with 16,000 zombies.

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Re^6: NaNs are true by syphilis (Archbishop) on Mar 01, 2011 at 02:56 UTC
What happens if you add NaN to zero? The usual rules apply. NaN+0 equals Nan, so `( 0 + $MPFR_NaN_obj )` returns a Math::MPFR object (courtesy of overloading of '+') that has a value of NaN, which is false. Cheers, Rob	[reply] [d/l]
Re^7: NaNs are true by jdporter (Paladin) on Mar 01, 2011 at 03:49 UTC
... has a value of NaN, which is false. Ok, I'm confused. In your OP, you say NaNs are true. Now you're saying they're false. Update: I see, you're talking about your overloaded version, which changes the "sign" of NaN. Ok, I agree that changing that is a Bad Idea in general, because of the violation of expectations. So, I guess you'll be stuck (assuming you ditch your overloaded version) doing an explicit test for NaN... `if ( $obj == NaN or $obj ) # true if true or NaN` [download] in which case, you could wrap it in a new method: `sub isTrue # ! { my $obj = shift; $obj == NaN \|\| $obj }` [download]	[reply] [d/l] [select]