Edit report at https://bugs.php.net/bug.php?id=46492&edit=1

 ID:                 46492
 Comment by:         v_cadet at yahoo dot fr
 Reported by:        email at davekok dot nl
 Summary:            array instanceof Traversable results false
 Status:             Not a bug
 Type:               Bug
 Package:            SPL related
 Operating System:   linux 2.6
 PHP Version:        5.2.6
 Block user comment: N
 Private report:     N

 New Comment:

Sorry but this report *does* make quite a lot of sense. For instance a function 
may expect any traversable object as an argument, which makes PHP automatically 
validate calls to that function. Example:

function foo( Traversable $item_list ) { /* Do something */ }

Since arrays *are* traversable somehow, this simple function would make the 
code quite clear and obvious, automatically accept a small range of possible 
argument types and yielding runtime exception otherwise. Now since arrays are 
not objects, one must bloat the code and wrap arrays into Traversable objects. 
Granted this can be achieved in a very simple way but this results in uselessly 
adding code, regardless of how simple it can be.

I have run into the need of such a nice feature in a recent PHP application. In 
my case I have removed the Traversable hint and added checks (as you suggested) 
against the argument for acceptable types. But I for one yet don't like that 
workaround.


Previous Comments:
------------------------------------------------------------------------
[2008-11-05 11:08:00] col...@php.net

Sorry, but your problem does not imply a bug in PHP itself.  For a
list of more appropriate places to ask for help using PHP, please
visit http://www.php.net/support.php as this bug system is not the
appropriate forum for asking support questions.  Due to the volume
of reports we can not explain in detail here why your report is not
a bug.  The support channels will be able to provide an explanation
for you.

Thank you for your interest in PHP.

array() is not an object of any class. Hence, it can't implement any interface 
such as Traversable.

You probably want: is_array($o) || $o instanceof Traversable

------------------------------------------------------------------------
[2008-11-05 09:37:37] email at davekok dot nl

Description:
------------
When executing the expression

(array() instanceof Traversable)

it results in false.

I'm not really sure if an array is seen as an object in PHP. But since there is 
no function like is_traversable. I expected this to work.


Reproduce code:
---------------
$a = array();

return ($a instanceof Traversable)


Expected result:
----------------
true

Actual result:
--------------
false


------------------------------------------------------------------------



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