Linked List

My implementation of a singly linked list in JavaScript (singly meaning unidirectional and can be traversed in only one direction)

Why Linked Lists?

Linked lists are the base structures that other more complex data structures are derived from and store data in a series of "nodes". If you're here you know the differences, and if not, then you should read more about them, their advantages and disadvantages, etc.

Install

git clone https://github.com/ahadb/linked-list or whatever your preferred method is

To be distributed on NPM.

Use

import LinkedList from "./linked-list.js";

const singlyLinkedList = new LinkedList();

// objects as nodes
const node1 = { value: 1, key: 'one' };
const node2 = { value: 2, key: 'two' };

singlyLinkedList
  .append(node1)
  .prepend(node2);

singlyLinkedList.head // => nodeValue1
singlyLinkedList.tail // => nodeValue2

const nodeStringifier = value => `${value.key}:${value.value}`;
singlyLinkedList.toString(nodeStringifier; // => "two:2,one:1"

API

LinkedListNode

The building block of Singly Linked List is a node.

const node2 = new LinkedListNode(2);
const node1 = new LinkedListNode(1, node2);

LinkedList

Create a new Singly Linked List with no items.

const singlyLinkedList = new LinkedList();

LinkedList.prepend

Prepend a node to your Singly Linked List.

const singlyLinkedList = new LinkedList();
singlyLinkedList.prepend(2);

LinkedList.append

Append a node to your Singly Linked List.

const singlyLinkedList = new LinkedList();
singlyLinkedList.append(2);

LinkedList.delete

Delete a node by value anywhere in your Singly Linked List.

const singlyLinkedList = new LinkedList();

singlyLinkedList.append(1);
singlyLinkedList.append(2);
singlyLinkedList.append(3);

singlyLinkedList.delete(3);

LinkedList.deleteHead

Delete the head node in your Singly Linked List.

const singlyLinkedList = new LinkedList();

singlyLinkedList.append(1);
singlyLinkedList.append(2);
singlyLinkedList.append(3);

singlyLinkedList.deleteHead();

LinkedList.deleteTail

Delete the tail node in your Singly Linked List.

const singlyLinkedList = new LinkedList();

singlyLinkedList.append(1);
singlyLinkedList.prepend(2);
singlyLinkedList.prepend(3);

singlyLinkedList.deleteTail();

LinkedList.find

Find a node by value in your Singly Linked List.

const singlyLinkedList = new LinkedList();

singlyLinkedList.append(1);

singlyLinkedList
  .append(2)
  .append(3);

// you can use a callback as well here
singlyLinkedList.find({ value: 2 });

LinkedList.toArray

Convert your Singly Linked List to an Array

const singlyLinkedList = new LinkedList();

// objects as nodes
const node1 = { value: 1, key: 'one' };
const node2 = { value: 2, key: 'two' };

singlyLinkedList
  .append(node1)
  .prepend(node2);

singlyLinkedList.toArray()

LinkedList.toString

Convert your Singly Linked List to a String

const singlyLinkedList = new LinkedList();

// objects as nodes
const node1 = { value: 1, key: 'one' };
const node2 = { value: 2, key: 'two' };

singlyLinkedList
  .append(node1)
  .prepend(node2);

singlyLinkedList.toString()