Package Exports

circularr

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (circularr) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

Circularr

Fixed size array

Install

npm i circularr

Usage

import Circularr from 'circularr'

// Create from
const arrFrom = Circularr.from([1, 2, 3, 4, 5])

// Create new with fixed size
const arr = new Circularr(3) // [undefined, undefined, undefined]

// fill using value
arr.fill(0)   // [0, 0, 0]

// shift in some values
arr.shift(16) // [0, 0, 16]
arr.shift(32) // [0, 16, 32]

// check contents
console.log(...arr) // undefined, 16, 32

Api

Fill

fill(value: T): this

Fills the array using value, effectively resetting it. Returns this.

const array = new Circularr(3) // [undefined, undefined, undefined]

/* mutate fill */
array.fill(0) // [0, 0, 0]

Shift

shift(value: T): T

shift method pushes the value to the end of the array, wherein the first value gets popped out and returned.

const array = new Circularr(3).fill(0)

array.shift(8)   // [0, 0, 8] => 0
array.shift(16)  // [0, 8, 16] => 0
array.shift(32)  // [8, 16, 32] => 0
array.shift(64)  // [16, 32, 64] => 8
array.length     // 3

Unshift

unshift(value: T): T

unshift does the opposite. It pushes the value to the front, popping the last value out.

const array = new Circularr(3).fill(0)

array.unshift(8)   // [8, 0, 0] => 0
array.unshift(16)  // [16, 8, 0] => 0
array.unshift(32)  // [32, 16, 8] => 0
array.unshift(64)  // [64, 32, 16] => 8
array.length       // 3

Slice

slice(beginIndex?: number, endIndex?: number): Circularr<T>

slice does works the same way as Array.slice().

const array = Circularr.from([1, 2, 3, 4])

const sliced = array.slice(1, 3) // [2, 3]

Trim

trim(): Circularr<T>

trim returns new Circularr with removed undefined values from both ends.

const array = new Circularr<number>(5)

array.shift(1)
array.shift(2)

const trimmed = array.trim() // [1, 2]

At

at(index: number): T | undefined

at returns element at the index. For negative indices - undefined is returned. For overflow indices - undefined is returned

const array = new Circularr<number>(5)

array.shift(1)
array.shift(2)

const val0 = array.at(0) // undefined
const val1 = array.at(3) // 1
const val2 = array.at(4) // 2
const val3 = array.at(5) // undefined

WrapAt

wrapAt(index: number): T | undefined

wrapAt returns element at the index. For negative and overflow indices - the index will be wrapped around, and correct value will be returned

const array = new Circularr<number>(5)

array.shift(1)
array.shift(2)

const val0 = array.at(0) // undefined
const val1 = array.at(3) // 1
const val2 = array.at(4) // 2
const val3 = array.at(8) // 1
const val3 = array.at(9) // 2

Iterable

Circularr implements iterable protocol, so it can be used with any standard iterable syntax

const array = Circularr.from([1, 2, 3])

// array destructuring
const [firstValue] = array

// destructuring copy
const copyToArray = [...array]

// for..of syntax
for (let value of array) {
  console.log(value)
}