Immutable-dll

A Doubly linked list featuring functional methods, immutable data and a fluent interface.

See the Full documentation or Checkout on Github

Install

yarn add immutable-dll
npm install -s immutable-dll

Usage

Typescript

import {DLinkedList} from 'immutable-dll'

const dll = DLinkedList.fromArray<number>([1,2,3])
const double = dll.map<number>(v => v * 2)
const triple = double.map<number>(v => v * 3)
const values = triple.map<string>(v => `value: ${v}`)

dll.toArray() // [1,2,3]
values.toArray() // [ 'value: 6', 'value: 12', 'value: 18' ]

Javascript

const {DLinkedList} = require('immutable-dll')

const dll = DLinkedList.fromArray([1,2,3])
const double = dll.map(v => v * 2)
const triple = double.map(v => v * 3)
const values = triple.map(v => `value: ${v}`)

dll.toArray() // [1,2,3]
values.toArray() // [ 'value: 6', 'value: 12', 'value: 18' ]

Immutable Values

Plain objects as determined by lodash.isplainobject) and arrays are deeply cloned when they are added to the list, and again deeply cloned when they are extracted, both directly and when provided to an iterator function.

Every method that returns a list value will return a deeply cloned object provided it is a plain object or array.

Javascript Primitive types are unique and passed by value. Functions are returned directly with no modification.

import {DLinkedList} from 'immutable-dll'

const arr = [{a: 1, b: 2}, {a: 3, b: 4}, {a: 5, b: 6}]

const dll = DLinkedList.fromArray(arr) 
const double = dll.map<{a: number, b: number}>(v => ({a: v.a * 2, b: v.b * 2}))

arr[0].a = 100
arr[0].b = 200
arr[1] = {a: 0, b: 0}

arr // [ { a: 100, b: 200 }, { a: 0, b: 0 }, { a: 5, b: 6 } ]
dll.toArray() // [{a: 1, b: 2}, {a: 3, b: 4}, {a: 5, b: 6}]
double.toArray() // [ { a: 2, b: 4 }, { a: 6, b: 8 }, { a: 10, b: 12 } ]

Full documentation can be found here!

 let f: asyncMapIteratee<number, number> = (value: number) => Promise.resolve(value * value)

 let f: asyncReduceIteratee<number, number> = (acc, value) => {
   acc += value
   return Promise.resolve(acc)
 }

 let f: eachIteratee<number> = (value: number) => `I have this value: ${value}`

 let f: filterPredicate<number> = (value: number) => return true

 let f: mapIteratee<number, string> = (value: number) => `I have this value: ${value}`

 let f: reduceIteratee<number, number> = (acc, value) => {
   acc += value
   return acc
 }