OperatorSwift

# <<=(_:_:)

Stores the result of shifting a value’s binary representation the specified number of digits to the left in the left-hand-side variable.

``static func <<= <Other>(lhs: inout Self, rhs: Other) where Other : BinaryInteger``

## Parameters

lhs

The value to shift.

rhs

The number of bits to shift `lhs` to the left.

## Overview

The `<<` operator performs a smart shift, which defines a result for a shift of any value.

• Using a negative value for `rhs` performs a right shift using `abs(rhs)`.

• Using a value for `rhs` that is greater than or equal to the bit width of `lhs` is an overshift, resulting in zero.

• Using any other value for `rhs` performs a left shift on `lhs` by that amount.

The following example defines `x` as an instance of `UInt8`, an 8-bit, unsigned integer type. If you use `2` as the right-hand-side value in an operation on `x`, the value is shifted left by two bits.

``````var x: UInt8 = 30                 // 0b00011110
x <<= 2
// x == 120                       // 0b01111000``````

If you use `11` as `rhs`, `x` is overshifted such that all of its bits are set to zero.

``````var y: UInt8 = 30                 // 0b00011110
y <<= 11
// y == 0                         // 0b00000000``````

Using a negative value as `rhs` is the same as performing a right shift with `abs(rhs)`.

``````var a: UInt8 = 30                 // 0b00011110
a <<= -3
// a == 3                         // 0b00000011

var b: UInt8 = 30                 // 0b00011110
b >>= 3
// b == 3                         // 0b00000011``````