javascript operator
Left shift assignment (<<=)
The left shift assignment (<<=) operator performs left shift on the two operands and assigns the result to the left operand.
Interactive exampleOpen the canonical MDN source to run this embedded demo.
let a = 5; // 00000000000000000000000000000101
a <<= 2; // 00000000000000000000000000010100
console.log(a);
// Expected output: 20
Syntax
x <<= y
Description
x <<= y is equivalent to x = x << y, except that the expression x is only evaluated once.
Examples
Using left shift assignment
let a = 5;
// 00000000000000000000000000000101
a <<= 2; // 20
// 00000000000000000000000000010100
let b = 5n;
b <<= 2n; // 20n
Specifications
SpecificationsStandards references are available on the canonical MDN page.
Browser compatibility
Browser compatibilityCompatibility data is available on the canonical MDN page.