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# Nullish Coalescing Assignment (??=) Operator in JavaScript

This is a new operator introduced by javascript. This operator is represented by x ??= y and it is called Logical nullish assignment operator. Only if the value of x is nullish then the value of y will be assigned to x that means if the value of x is null or undefined then the value of y will be assigned to x.

Let’s discuss how this logical nullish assignment operator works. Firstly we all know that logical nullish assignment is represented as x ??= y, this is derived by two operators nullish coalescing operator and assignment operator we can also write it as x ?? (x = y). Now javascript checks the x first, if it is nullish then the value of y will be assigned to x.

Syntax :

x ??= y  // Means : x ?? (x = y)

Example 1 :

## Javascript

 let x = 12;let y = null;  let z = 13;  // The value of x will become // unchanged because x is not nullish.x ??= z;  // The value of y will be // changed because y is nullish.y ??= z;    console.log(x)    // 12console.log(y)    // 13

Output :

12
13

Example 2 :

## Javascript

 let x = {  name : "Ram"}  // The value of name will remain// unchanged because x.name is not nullishx.name ??= "Shyam";  // There is no any property named age in object x .// So the value of x.age will be // undefined and undefined means nullish.// that's why the value of age will be assigned.x.age ??= 18;  console.log(x.name)  // Ramconsole.log(x.age)   // 18

Output :

"Ram"
18

Example 3:

## HTML



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Output :

Supported browsers

• Chrome 85
• Edge 85
• Firefox 79
• Safari 14

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