Re: [PHP-DEV] Bug #3922 Updated: == bug From: Hartmut Holzgraefe (hartmut <email protected>)
Date: 05/20/00

Zeev Suraski wrote:
> > 0 == 'N/A' -> true
> > 'N/A' == 0 -> false
>
> What do you mean by that? There's no difference between (0=='N/A') and
> ('N/A'==0) in both PHP 3.0 and 4.0 - both of the lvalue and rvalue
> behave in the same way.

uh, stupid me, did only the mind test, not the real thing :(
(influenced by browsing some c++ books lately)

but then this is an even more confusing behavior ...

i would have thought that '==' worked by casting the right
expression to the type of the left before comparing them
so the result for '0 == "N/A"' would by true due tue
'0 == (int)"N/A"' although not obvious in the first place,
but then '"N/A" == 0' should be interpreted as
'"N/A" == (string)0' resulting in false ...

knowing about lex, yacc and friends, i can see what's going
on here and i know that '===' is the answer but even i
assumed that '===' was more for resolving things like
'"1"==1' and never thought about this special case

anyway, i think closing the bug was still okay, i'll just edit out
the other-way-round part 

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