From: hans at velum dot net
Operating system: All
PHP version: 5.0.1
PHP Bug Type: Feature/Change Request
Bug description: instanceof requires class to be loaded
Description:
------------
[pasted from messages on internals@ list]
I like the new $obj instanceof ClassName way of checking class / interface
types, .... but this method does have one major drawback compared to the
old is_a() approach:
The class must be loaded in order to perform an instanceof check!
There are many situations where you do not want to have to load every
class to see whether a returned object is a class of that type. In
particular for driver classes, the current model requires loading *every*
possible driver in order to check to see which type of class was
returned.
is_a() works great, but has been deprecated and is now generating E_STRICT
errors.
Reproduce code:
---------------
[conributed by Sean Coates on internals@ list]
<?php
class Foo {}
$foo = unserialize('O:3:"Foo":0:{}');
echo '$foo is_a Foo? '. (is_a($foo, 'Foo') ? 'yes' : 'no') ."\n";
echo '$foo instanceof Foo? '. ($foo instanceof Foo ? 'yes' : 'no') ."\n";
?>
---- and ----
<?php
//class Foo {}
$foo = unserialize('O:3:"Foo":0:{}');
echo '$foo is_a Foo? '. (is_a($foo, 'Foo') ? 'yes' : 'no') ."\n";
echo '$foo instanceof Foo? '. ($foo instanceof Foo ? 'yes' : 'no') ."\n";
?>
Expected result:
----------------
$foo is_a Foo? yes
$foo instanceof Foo? yes
---- and ----
$foo is_a Foo? no
$foo instanceof Foo? no
Actual result:
--------------
$foo is_a Foo? yes
$foo instanceof Foo? yes
---- and ----
$foo is_a Foo? no
Fatal error: Class 'Foo' not found in
/home/sean/phpdoc/scripts/tmp/is_a.php on line 8
--
Edit bug report at http://bugs.php.net/?id=29736&edit=1
--
Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=29736&r=trysnapshot4
Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=29736&r=trysnapshot5
Fixed in CVS: http://bugs.php.net/fix.php?id=29736&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=29736&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=29736&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=29736&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=29736&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=29736&r=support
Expected behavior: http://bugs.php.net/fix.php?id=29736&r=notwrong
Not enough info: http://bugs.php.net/fix.php?id=29736&r=notenoughinfo
Submitted twice: http://bugs.php.net/fix.php?id=29736&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=29736&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=29736&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=29736&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=29736&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=29736&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=29736&r=float
