Bitwise AND assignment (&=)

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The bitwise AND assignment (&=) operator performs bitwise AND on the two operands and assigns the result to the left operand.

{{InteractiveExample("JavaScript Demo: Bitwise AND assignment (&=) operator", "shorter")}}

```js interactive-example let a = 5; // 00000000000000000000000000000101 a &= 3; // 00000000000000000000000000000011

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

## Syntax

```js-nolint
x &= y

Description#

x &= y is equivalent to x = x & y, except that the expression x is only evaluated once.

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

let b = 5n;
b &= 2n; // 0n