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To: Todd Ruth <truth@proposaltech.com>
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Subject: Re: [PHP-DEV] '1.8' == 1.8 can return false
From: rasmus@lerdorf.com (Rasmus Lerdorf)

There is no bug here.  Please read:

http://docs.sun.com/source/806-3568/ncg_goldberg.html

-Rasmus

Todd Ruth wrote:
> I'm thinking there must be a bug in the heart of php
> causing this.  I'll debug it, but I haven't looked at
> php source code in a few years and would like a tip as
> to which files are involved in evaluating "==".  Here
> is a fragment from my code and the output:
> 
> ...
> print "<pre>\n";
> var_dump($max);
> var_dump($nms);
> var_dump($nms == $max);
> $max = (float)$max;
> $nms = (string)$nms;
> var_dump($max);
> var_dump($nms);
> var_dump($nms == $max);
> $max = (string)$max;
> $nms = (float)$nms;
> var_dump($max);
> var_dump($nms);
> var_dump($nms == $max);
> print "</pre>\n";
> ...
> 
> string(3) "1.8"
> float(1.8)
> bool(false)
> float(1.8)
> string(3) "1.8"
> bool(true)
> string(3) "1.8"
> float(1.8)
> bool(true)
> 
> I found this using php 5.2.3.  I just upgraded to php 5.2.5
> and am receiving the exact same result.  Obviously, I can't
> reproduce it with a simple var_dump("1.8"==1.8).  :(
> I guess something is getting corrupted, and I will add debug
> output until I find out what (or Murphy removes the problem
> by adding debug output; then I'm not sure what I'll do).
> 
> Thanks for any tips on which files I should look at it.