Edit report at https://bugs.php.net/bug.php?id=60944&edit=1
ID: 60944
Comment by: phpmpan at mpan dot pl
Reported by: lampacz+php at gmail dot com
Summary: Unable to detect if variable exists vs. is null
Status: Open
Type: Feature/Change Request
Package: Variables related
Operating System: Linux
PHP Version: 5.3.9
Block user comment: N
Private report: N
New Comment:
What is the rationale for introducing such function? Can you provide any
real-life example when it is neccessary to distinguish between an undefined
global variable and a global variable set to `NULL`? The question is important,
as use of global variables is getting less popular. Adding a new function, that
will duplicate already existing functionality (proposed by Laruence), is IMHO
not a good idea.
Previous Comments:
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[2012-02-01 10:39:28] lampacz+php at gmail dot com
Marvelous.
Sugestion for new function: is_defined(mixed $var)
which internally return array_key_exists($var, get_defined_vars()); ?
Thank you for.
------------------------------------------------------------------------
[2012-02-01 09:54:15] larue...@php.net
<?php
$a = null;
var_dump(array_key_exists('a', get_defined_vars())); //or $GLOBALS
?>
------------------------------------------------------------------------
[2012-02-01 08:05:10] lampacz+php at gmail dot com
Description:
------------
There is no difference between $x = NULL and unset($a). So i'm unable to detect
if variable was defined (so it can be defined and be filled with null)
http://www.php.net/manual/en/types.comparisons.php Table Comparisons of $x with
PHP functions, rows 2 - 4 gives same results
Expected result:
----------------
Different results for undefined variables and null variables
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Edit this bug report at https://bugs.php.net/bug.php?id=60944&edit=1
