Bug #69476 [Com]: is_null() must not throw warnings

Edit report at https://bugs.php.net/bug.php?id=69476&edit=1 ID: 69476 Comment by: nikic@php.net Reported by: spam2 at rhsoft dot net Summary: is_null() must not throw warnings Status: Not a bug Type: Bug Package: Scripting Engine problem Operating System: Linux PHP Version: Irrelevant Block user comment: N Private report: N New Comment: @cmb The question is how to detect whether a variable is defined, but null. @op You correctly surmised that there is no (obvious) way to do this. Could you please describe why you consider this to be necessary? Checking whether a *simple* variable is defined is, as far as I can tell, useless in any case. If you want to check whether an array key exists (and is null) you can use array_key_exists. Similarly for objects there is property_exists. Previous Comments: ------------------------------------------------------------------------ [2015-04-17 16:48:53] cmb@php.net > how [...] do you test if a variable is defined with the isset() behavior > saying no if the value is NULL isset($var) && !is_null($var) ------------------------------------------------------------------------ [2015-04-17 15:49:18] spam2 at rhsoft dot net bullshit - isset() don't work when a variable is defined and contains NULL, you should read your own documentation [harry@srv-rhsoft:/mnt/data/downloads]$ php test.php [harry@srv-rhsoft:/mnt/data/downloads]$ cat test.php <?php $x = NULL; if(isset($x)) { echo "defined\n"; } ?> ------------------------------------------------------------------------ [2015-04-17 15:45:45] chx@php.net You want isset() and this has nothing to do with the specification. ------------------------------------------------------------------------ [2015-04-17 15:40:49] spam2 at rhsoft dot net Description: ------------ since isset() returns false in case a variable contains NULL (which is a major design error) is_null() MUST not throw a warning in case of a undefined variable Test script: --------------- <?php if(isset($nicht_definiert) || is_null($nicht_definiert)) { echo "defined\n"; } ?> Expected result: ---------------- no warning or a sane isset() behavior with sanity in mind how the hell do you test if a variable is defined with the isset() behavior saying no if the value is NULL Actual result: -------------- Notice: Undefined variable: nicht_definiert in /mnt/data/downloads/test.php on line 2 defined ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=69476&edit=1