bitwise-rotation

Rotate values with a bitwise rotation.

> In computer programming, a circular shift (or bitwise rotation) is a shift
> operator that shifts all bits of its operand. Unlike an arithmetic shift, a
> circular shift does not preserve a number's sign bit or distinguish a number's
> exponent from its significand (sometimes referred to as the mantissa).
> — [Wikipedia][1]

How to Use

``js
import bitwiseRotation from 'bitwise-rotation';

// Set the bit-width/length; max of 32, min of 0.
const rotationObject = bitwiseRotation(8);

// Returns an object with rotate right (ror) and rotate left (rol) methods.
const { ror, rol } = rotationObject;

// Rotate a value by an amount.
rol(101, 2); // 149
ror(101, 2); // 89
`

Visual Example

`js
import { rolInt8, rorInt8 } from 'bitwise-rotation';

const value = 1;
value.toString(2); // 00000001
rolInt8(value, 1).toString(2); // 00000010
rolInt8(value, 2).toString(2); // 00000100
rolInt8(value, 3).toString(2); // 00001000
rolInt8(value, 4).toString(2); // 00010000
rorInt8(value, 4).toString(2); // 00010000
rorInt8(value, 3).toString(2); // 00100000
rorInt8(value, 2).toString(2); // 01000000
rorInt8(value, 1).toString(2); // 10000000
`

API

$3

A function to specify a custom bitWidth that returns a rotationObject.

* bitWidth: An integer between \[0, 32\] that specifies the limit for
rotating values.

> bitWidth cannot be larger than 32 because operands of all bitwise operators
> are converted to signed 32-bit integers in two's complement format.
> — [MDN][2]

#### rotationObject

An object with the following 2 methods for rotating bytes:

* ror(value, rotation): Rotate a byte to the right by the specified amount of
rotation.

* value: Decimal representation of a value to be rotated.

* rotation: The amount to rotate the value by.

* rol(value, rotation): Rotate a byte to the left by the specified amount of
rotation.

* value: Decimal representation of a byte to be rotated.

* rotation: The amount to rotate the value` by.

Both methods return a decimal representation of a value rotated.

$3

Convenience method for rotating an 8-bit value right.

$3

Convenience method for rotating an 8-bit value left.

$3

Convenience method for rotating a 16-bit value right.

$3

Convenience method for rotating a 16-bit value left.

$3

Convenience method for rotating a 32-bit value right.

$3

Convenience method for rotating a 32-bit value left.

[1]: https://en.wikipedia.org/wiki/Circular_shift
[2]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_Operators#Signed_32-bit_integers