JavaScript Logical AND assignment (&&=) Operator (original) (raw)

Last Updated : 06 Jan, 2023

This operator is represented by x &&= y, and it is called the logical AND assignment operator. It assigns the value of y into x only if x is a truthy value.

We use this operator x &&= y like this. Now break this expression into two parts, x && (x = y). If the value of x is true, then the statement (x = y) executes, and the value of y gets stored into x but if the value of x is a falsy value then the statement (x = y) does not get executed.

Syntax :

x &&= y

is equivalent to

x && (x = y)

Example: This example shows the basic use of the Javascript Logical AND assignment(&&=) operator.

Javascript

<script>

`` let name = {

`` firstName: "Ram" ,

`` lastName: "" ,

`` };

`` console.log(name.firstName);

`` name.firstName &&= "Shyam" ;

`` console.log(name.firstName);

`` console.log(name.lastName);

`` name.lastName &&= "Kumar" ;

`` console.log(name.lastName);

</script>

Output :

"Ram" "Shyam" "" ""

Example 2: This example shows the basic use of the Javascript Logical AND assignment(&&=) operator.

HTML

< h1 style = "color:green" >

`` Geeksforgeeks

</ h1 >

< h3 >

`` Javascript Logical AND assignment(&&=) operator

</ h3 >

< p id = "print_arr" ></ p >

< script >

`` let arr = [1, 2, "apple", null, undefined, []]

`` // Replace each truthy values with "gfg"

`` arr.forEach((item, index)=>{

`` arr[index] &&= "gfg"

`` })

`` document.getElementById("print_arr").innerText = arr.toString();

`` //console.log(arr)

</ script >

Output :

Javascript Logical AND assignment(&&=) operator

Javascript Logical AND assignment(&&=) operator

We have a complete list of Javascript Operators, to check those please go through the Javascript Operators Complete Reference article.

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