The WeakReference class

    (PHP 7 >= 7.4.0, PHP 8)

    Introduction

    Weak references allow the programmer to retain a reference to an object which does not prevent the object from being destroyed. They are useful for implementing cache like structures.

    WeakReferences cannot be serialized.

    Class synopsis

    finalclassWeakReference {
    public__construct()
    publicstaticcreate(object$object): WeakReference
    publicget(): ?object
    }

    WeakReference Examples

    Example #1 Basic WeakReference Usage

    <?php
    $obj     = new stdClass;
    $weakref = WeakReference::create($obj);
    var_dump($weakref->get());
    unset(    $obj);
    var_dump($weakref->get());
    ?>

    The above example will output something similar to:

     object(stdClass)#1 (0) { } NULL

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