Dll NPM | npm.io

dll

A lightweight, fast & flexible doubly linked list for JavaScript.

var currentID = 0;

function Food (name) {
  this.name = name;

  // a unique id field is required:
  this._id = currentID;
  currentID += 1;
}

var entityA = new Food('Bacon'),
    entityB = new Food('Brocolli'),
    entityC = new Food('Sausage'),
    entityD = new Food('Steak');

var LinkedList = require('dll');
var list = new LinkedList();

list.add(entityA);
list.add(entityB);
list.add(entityC);
list.add(entityD);

console.log(list.length); // "4"

// Iterating is easy:
var itr = list.first;
while (itr) {
  console.log(itr.obj.name);
  itr = itr.next;
}
// Output:
//   Bacon
//   Brocolli
//   Sausage
//   Steak

// Or even easier:
list.each(function (obj) {
  console.log (itr.obj.name);
});

assert( list.contains(entityC) === true );

list.remove(entityC);

assert( list.contains(entityC) === false );

// Iterating backwards is easy:
itr = list.last;
while (itr) {
  console.log(itr.obj.name);
  itr = itr.prev;
}
// Output:
//   Steak
//   Sausage
//   Bacon

list.clear();
console.log(list.length); // "0"

Caveats

Only objects are supported. No primitives.
Objects must have a unique ID property (default is _id, but it can be changed with dll.config.idPropertyName).
Duplicate items are not supported.

API

var LinkedList = require('dll');

LinkedList.config.idPropertyName

Type: String Default: "_id"

The name of the property used to uniquely identify objects.

You are required to have a unique ID property on any objects that are added to a linked list, but you can call it whatever you want by changing the string value of this property.