linkedlist-js

    1.3.0 • Public • Published

    LinkedList.js

    A simple doubly linked list implementation in Javascript.

    Installation

    npm install linkedlist-js
    

    Usage

    require the module...

    var List = require('linkedlist-js').List;

    instantiate a List object...

    var list = new List();
     
    // PUSH!
    list.push('HUEHUE');

    Traversing the List

    with each(callback)

    list.each(function (index, node) {
        console.log(index + '' + node.value());
    });

    like a badass

    var node = list.head();
     
    while (node != null) {
        console.log(node.value());
        node = node.next();
    }

    List API

    Adding Nodes

    push(value)

    Creates a node with the value specified, adds it to the end of the list and returns the Node object.

    var a = list.push('A');
    a.value(); //'A'

    unshift(value)

    Creates a node with the value specified, adds it to the beginning of the list and returns the Node object.

    var b = list.unshift('B');
    b.value(); //'B'

    Accessing Nodes

    pop

    Returns the tail Node and removes it from the list.

    var list = new List();
    list.push('A');
    list.push('B');
    
    list.pop().value(); //'B'
    

    shift

    Returns the head Node and removes it from the list.

    var list = new List();
    list.push('A');
    list.push('B');
    
    list.shift().value(); //'A'
    

    get(index)

    Returns the Node at the specified index. (Linear Lookup, not very performant)

    var list = new List();
    list.push('A');
    list.push('B');
    list.push('C');
     
    list.get(1).value(); //'B'

    Peeking

    head()

    Returns the head Node or null in list is empty

    var list = new List();
    var node_a = list.push('A');
    var node_b = list.push('B');
     
    list.head() === node_a; // true

    tail()

    Returns the tail Node or null in list is empty

    var list = new List();
    var node_a = list.push('A');
    var node_b = list.push('B');
     
    list.tail() === node_b; // true

    Searching

    find(value)

    Find the node with the specified value and returns it. (Linear search, not very performant)

    var list = new List();
    list.push('A');
    var node_b = list.push('B');
     
    list.find('B') === node_b; // true

    Misc

    set(index, value)

    Sets the value of the Node at the specifiec index.

    var list = new List();
    list.push('A');
     
    list.set(0, 'B');
    list.head().value(); // 'B'

    count()

    Returns the number of Nodes in the list.

    var list = new List();
    list.push('A');
    list.push('B');
     
    list.count(); // 2

    isEmpty()

    Returns true if list has no Nodes and false if otherwise.

    var list = new List();
    list.isEmpty(); // true
     
    list.push('A');
    list.isEmpty(); // false

    truncateTo(length)

    Truncates the list to the specified size.

    var list = new List();
    list.push('A');
    list.push('B');
    
    list.truncateTo(1);
    list.count(); // 1
    

    empty()

    Same as calling truncateTo(0). Empties the list.

    var list = new List();
    list.push('A');
    list.push('B');
    
    list.empty();
    
    list.count();   // 0
    list.isEmpty(); // true
    

    asArray()

    Returns the list as an Array.

    var list = new List();
    list.push('A');
    list.push('B');
     
    list.asArray(); // ['A', 'B']

    Node API

    Getters

    value()

    Returns the value of the Node

    previous()

    Returns the previous Node in the list of null if the node is the forst Node.

    next()

    Returns the next Node in the list of null if the node is the last Node.

    Setters

    set(value)

    Sets the value of the node

    var node = new Node();
    node.set('A');
    
    node.value(); // 'A'
    

    setPrevious(Node node)

    Sets the previous pointer of the Node

    var node_a = new Node();
    var node_b = new Node();
    node_b.setPrevious(node_a);
    
    node_b.previous() === node_a; // true
    

    setNext(Node node)

    Sets the next pointer of the Node

    var node_a = new Node();
    var node_b = new Node();
    node_a.setNext(node_b);
    
    node_a.next() === node_b; // true
    

    Misc

    isHead()

    Retunrs true if the node is the first node in the list.

    var list = new List();
    list.push('A');
    list.push('B');
     
    list.head().isHead(); // true

    isTail()

    Retunrs true if the node is the last node in the list.

    var list = new List();
    list.push('A');
    list.push('B');
     
    list.tail().isTail(); // true

    Running Tests

    npm test
    

    if you have mocha installed, you may also run

    mocha tests
    

    Install

    npm i linkedlist-js

    DownloadsWeekly Downloads

    7

    Version

    1.3.0

    License

    MIT

    Last publish

    Collaborators

    • omranjamal