Fixed size array
npm i circularr
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 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(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 // 3unshift(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 // 3slice(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(): 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(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) // undefinedwrapAt(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) // 2Circularr 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)
}