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AND (&=) - JavaScript | MDN
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AND (&=)

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This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 7.

AND (&=) , AND .

In this article

let a = 5; // 00000000000000000000000000000101
a &= 3; // 00000000000000000000000000000011

console.log(a); // 00000000000000000000000000000001
// Expected output: 1

js
x &= y // x = x & y

AND

js
let a = 5;
// 5:     00000000000000000000000000000101
// 2:     00000000000000000000000000000010
a &= 2; // 0

Specification
ECMAScript 2027 LanguageSpecification
# sec-assignment-operators

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