WeakRef is a constructor that is built-in for creating a reference to an object in a weak manner that is the WeakRef does not itself keep the object from being garbage collected. The deref() method is a feature of WeakRef cases with which you can determine if the referenced object still exists.

Syntax

weakRef.deref();

Parameter:

The deref() does not take any parameters.

Return type:

The deref() returns, the target object referred by WeakRef if it still exists or undefined, if the object has been garbage collected.

Approach

• Create an object with a property name.
• To get the referenced object, the def () method is invoked on weaker.
• It implies that properties for the object can be accessed if dereferencedObj is true.
• If it’s undefined, then it means that the object has been garbage collected.

Example: The example below shows the JavaScript WeakRef.prototype. def () and check for the object’s existence.

let obj = { name: "Pankaj" };
let weakRef = new WeakRef(obj);

// Dereference the weak reference only once
let dereferencedObj = weakRef.deref(); 

if (dereferencedObj) {
    console.log("Object still exists:", dereferencedObj.name);
} else {
    console.log("Object has been garbage collected");
}

Object still exists: Pankaj