Comparing objects on PHP5
| From: | Rui Hirokawa | Date: | Sun, 09 May 2004 07:43:53 +0000 |
| Subject: | Comparing objects on PHP5 | ||
| Groups: | php.internals | ||
| Request: | Send a blank email to internals+get-9741@lists.php.net to get a copy of this message | ||
Hi,
I think objects comparison in PHP5 has problems.
Here is small sample code,
<?php
class Foo {
var $v = 1;
}
class Boo {
var $v = 1;
}
$a = new Foo;
$b = new Foo;
$c = new Boo;
$d = new Foo;
$d->v = 2;
$e = $a;
// value comparison
echo $a == $b ? "same," : "not same,";
echo $a == $c ? "same," : "not same,";
echo $a == $d ? "same," : "not same,";
echo $a == $e ? "same" : "not same";
echo "\n";
// value and type comparison
echo $a === $b ? "same," : "not same,";
echo $a === $c ? "same," : "not same,";
echo $a === $d ? "same," : "not same,";
echo $a === $e ? "same" : "not same";
?>
The output from PHP4 and PHP5(ze1_compat on/off) is,
PHP 4.3.6 :
same,not same,not same,same
same,not same,not same,same
PHP 5.0.0RC2 zend.ze1_compatibility_mode=off :
same,not same,not same,same
(Notice: Object of class [Foo|Boo] could not be converted to integer)
not same,not same,not same,same
PHP 5.0.0RC2 zend.ze1_compatibility_mode=on :
same,same,not same,same
not same,not same,not same,not same
The problem and question are,
1. the different class is recognised as same in PHP5 (ze1_compat=on).
2. the same object is recognised as different in PHP5 (ze1_compat=on).
3. Why integer casting of object was implicitly applied in PHP5
(ze1_compat=off) ?
--
Rui Hirokawa <rui_hirokawa@ybb.ne.jp>