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WeakRef() constructor - JavaScript | MDN
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WeakRef() constructor
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.
* Some parts of this feature may have varying levels of support.
The WeakRef() constructor creates WeakRef objects.
Syntax
js
new WeakRef(target)
Parameters
target-
The target value the WeakRef should refer to (also called the referent). Must be an object or a non-registered symbol.
Return value
A new WeakRef object referring to the given target value.
Exceptions
TypeError-
Thrown if
targetis not an object or a non-registered symbol.
Examples
Creating a new WeakRef object
See the main WeakRef
page for a complete example.
js
class Counter {
constructor(element) {
// Remember a weak reference to a DOM element
this.ref = new WeakRef(element);
this.start();
}
}
Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-weak-ref-constructor |
Browser compatibility
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