[PHP-NOTES] note 130387 added to class.weakmap

WeakMap and SplObjectStorage have different behavior when iterating in a foreach loop. While the key in SplObjectStorage is the numeric index of the inner array, in the WeakMap the key is the object reference:

<?php
class A {}
	
$a = new A;

$objectStorage = new SplObjectStorage ();
$weakMap = new WeakMap();

$objectStorage [$a] = 1;
$weakMap[$a] = 1;

foreach($objectStorage as $key => $value) {
	var_dump($key); // prints: int(0)
}

foreach($weakMap as $key => $value) {
	var_dump($key); // prints: object(A)#1 (0) {}
}
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Server IP: 45.112.84.4
Probable Submitter: 80.90.5.137 (proxied: 2001:1308:2067:da00:5147:7d63:6d7b:8699)
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Manual Page -- https://php.net/manual/en/class.weakmap.php
Edit        -- https://main.php.net/note/edit/130387
Del: integrated  -- https://main.php.net/note/delete/130387/integrated
Del: useless     -- https://main.php.net/note/delete/130387/useless
Del: bad code    -- https://main.php.net/note/delete/130387/bad+code
Del: spam        -- https://main.php.net/note/delete/130387/spam
Del: non-english -- https://main.php.net/note/delete/130387/non-english
Del: in docs     -- https://main.php.net/note/delete/130387/in+docs
Del: other reasons-- https://main.php.net/note/delete/130387
Reject      -- https://main.php.net/note/reject/130387
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