```
operator <<= {
associativity right
precedence
assignment
}
```

### Declarations

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

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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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

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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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.

`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
```

**Parameters:**
**lhs:** The value to shift.
**rhs:** The number of bits to shift `lhs`

to the left.

#### Declaration

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

#### Declared In

`FixedWidthInteger`

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

The

`<<`

operator performs asmart shift, which defines a result for a shift of any value.`rhs`

performs a right shift using`abs(rhs)`

.`rhs`

that is greater than or equal to the bit width of`lhs`

is anovershift, resulting in zero.`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.If you use

`11`

as`rhs`

,`x`

is overshifted such that all of its bits are set to zero.Using a negative value as

`rhs`

is the same as performing a right shift with`abs(rhs)`

.Parameters:lhs:The value to shift.rhs:The number of bits to shift`lhs`

to the left.## Declaration

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

## Declared In

`FixedWidthInteger`