The WeakReference classWeakReference
&reftitle.intro;
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.
If the original object has been destroyed, &null; will be returned
when calling the WeakReference::get method.
The original object will be destroyed when the
refcount for it drops to zero;
creating weak references does not increase the refcount of the object being referenced.
WeakReferences cannot be serialized.
&reftitle.classsynopsis;
finalWeakReference&Methods;WeakReference ExamplesBasic WeakReference Usage
get());
unset($obj);
var_dump($weakref->get());
?>
]]>
&example.outputs.similar;
&reftitle.changelog;
&Version;&Description;8.4.0
The output of WeakReference::__debugInfo now includes
the referenced object, or NULL if the reference is no longer
valid.
&language.predefined.weakreference.construct;
&language.predefined.weakreference.create;
&language.predefined.weakreference.get;