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Demonstrates a PHP bug: It is possible to directly call the magic method "__construct".
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<?php | |
/** | |
* DirectCallToMagicMethodConstruct.php | |
* | |
* PHP 5.4.13 (cli) (built: Mar 15 2013 02:05:59) | |
* Copyright (c) 1997-2013 The PHP Group | |
* Zend Engine v2.4.0, Copyright (c) 1998-2013 Zend Technologies | |
* with Xdebug v2.2.1, Copyright (c) 2002-2012, by Derick Rethans | |
*/ | |
class ParentClass | |
{ | |
function __construct() | |
{ | |
echo __METHOD__, \PHP_EOL; | |
} | |
function __clone() | |
{ | |
} | |
} | |
class ChildClass extends ParentClass | |
{ | |
function __construct() | |
{ | |
echo __METHOD__, \PHP_EOL; | |
// The following call would result in endless recursion. | |
// $this->__construct(); | |
// Accessing the superclass is possible via the special name "parent". | |
// There is not distinction between member methods and static methods! | |
parent::__construct(); | |
} | |
} | |
// The "new" operator is used to create a new instance. This invokes the magic (interceptor) method "__construct" (if defined). | |
$example = new ChildClass; | |
// The "clone" operator is used to create a shallow copy of an object. This invokes the magic (interceptor) method "__clone" (if defined). | |
$clonedExample = clone $example; | |
// The following call would raise an \E_FATAL: Cannot call __clone() method on objects - use 'clone $obj' instead in [...] on line 45 | |
//$example->__clone(); | |
// The following call DOES NOT raise an \E_FATAL. From a clients point of view, it should do that with the following message: | |
// "Cannot call __construct() method on objects - use 'new <Class>' instead in [...] on line 49" | |
$example->__construct(); | |
// Question: Why is the behaviour different? |
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