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Request #39904 string -> boolean conversion of "\0" should give FALSE
Submitted: 2006-12-20 14:46 UTC Modified: 2014-10-12 14:30 UTC
Votes:1
Avg. Score:2.0 ± 0.0
Reproduced:1 of 1 (100.0%)
Same Version:1 (100.0%)
Same OS:0 (0.0%)
From: zizka at seznam dot cz Assigned:
Status: Wont fix Package: Scripting Engine problem
PHP Version: * OS: *
Private report: No CVE-ID: None
View Developer Edit
 [2006-12-20 14:46 UTC] zizka at seznam dot cz 
Description:
------------
It might be useful that (boolean)"\0" would give FALSE.
E.g. MySQL's BIT(1) column type can be used to store boolean values, but now PHP converts whatever value to TRUE.

Reproduce code:
---------------
header('Content-Type: text/plain');

echo "\nfalse: ".ord(false);
echo "\ntrue: ".ord(true);
echo "\n\\0: ".(boolean)("\0");
echo "\n\\1: ".(boolean)("\1");

// ord() is here just for thoughts context...

Expected result:
----------------
false: 0
true: 49
\0: 0
\1: 1

Actual result:
--------------
false: 0
true: 49
\0: 1  <----- HERE
\1: 1

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 [2009-04-18 19:11 UTC] dave at ifox dot com 
To correct, "\0" -> FALSE has not found itself into PHP, but "0" has, and that feature should be reversed.  It's not logical to assume the numerical value of alphanumeric strings in place of the programmer doing so with a numerical cast.

A bug report was even submitted that a string "false" should evaluate to FALSE when converted to boolean.  That won't happen, because PHP developers already know they made a mistake with the "0" hack.  Hopefully in a major version release it will be reversed and all non-empty strings will evaluate to TRUE.

Just like every other loosely-typed language on the planet.
 [2011-01-02 02:13 UTC] jani@php.net
-Summary: string -> boolean conversion of "\0" could give FALSE +Summary: string -> boolean conversion of "\0" should give FALSE -Package: Feature/Change Request +Package: Scripting Engine problem -Operating System: +Operating System: * -PHP Version: 5.2.0 +PHP Version: *
 [2014-10-12 14:30 UTC] nikic@php.net
-Status: Open +Status: Wont fix
 [2014-10-12 14:30 UTC] nikic@php.net 
From the experience of treating "0" as false (which is a PITA in many cases), also treating "\0" as false won't happen.
 
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