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WeakRef.prototype.deref() - JavaScript | MDN
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WeakRef.prototype.deref()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.
The deref() method of WeakRef instances returns this WeakRef's target value, or undefined if the target value has been garbage-collected.
Syntax
js
deref()
Parameters
None.
Return value
The target value of the WeakRef, which is either an object or a non-registered symbol. Returns undefined if the value has been garbage-collected.
Description
See the Notes on WeakRefs section of the WeakRef page for some important notes.
Examples
Using deref()
See the Examples
section of the WeakRef page for the complete example.
js
const tick = () => {
// Get the element from the weak reference, if it still exists
const element = this.ref.deref();
if (element) {
element.textContent = ++this.count;
} else {
// The element doesn't exist anymore
console.log("The element is gone.");
this.stop();
this.ref = null;
}
};
Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-weak-ref.prototype.deref |
Browser compatibility
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