doublelist

A fast-lookup key-value doubly-linked list implementation for nodejs.

Installation

npm install doublelist

Functionality

• doublelist(): Constructor. Returns a new doublelist instance.
• length: Returns the length of the list.
• add(key, value): Adds an element at the end of the list.
• append(key, value): As above.
• enqueue(key, value): As above.
• push(key, value): Adds an element at the beginning of the list.
• insert(insertkey, key, value): Adds an element after the element with key insertkey.
• pop(): Removes and returns the element at the beginning of the list, in the form [key, value].
• dequeue(): As above.
• remove(key): Removes and returns the value of the element with key key.
• clear(): Clears the list, removing all elements.
• flush(): As above.
• empty(): As above.
• get(key): Returns the value of the element with key key.
• find(key): As above.
• set(key, value): Assigns the value value to the element with key key.
• update(key, value): As above.
• hasKey(key): Returns whether or not the key key exists.
• foreach(callback): Iterates over the list, executing the callback callback on each element. Callback expects the signature: callback(key, value).
• toArray(): Returns an array representation of the list, in the form [[key1, value1], [key2, value2], ...].
• toDict(): Returns a dictionary representation of the list, in the form {key1: value1, key2: value2, ...}.

Example Code

var doublelist = require('doublelist')

var d = new doublelist()

d.add('armadillo', {'baboon':'crayfish'})
d.append('elephant', 5)
d.insert('armadillo', 'deer', null)
d.set('elephant', 500)
d.append('fennec', 'gorilla')
d.update('fennec', 'gopher')
console.log(d.remove('elephant'))
//500
d.insert('deer', 'earwig', 42.69)

d.foreach(function(key, value){
  console.log('KEY: ' + key + ', VALUE: ' + value)
})
//KEY: armadillo, VALUE: [object Object]
//KEY: deer, VALUE: null
//KEY: earwig, VALUE: 42.69
//KEY: fennec, VALUE: gopher

console.log(d.toArray())
//[ [ 'armadillo', { baboon: 'crayfish' } ],
//  [ 'deer', null ],
//  [ 'earwig', 42.69 ],
//  [ 'fennec', 'gopher' ] ]

console.log(d.toDict())
//[ armadillo: { baboon: 'crayfish' },
//  deer: null,
//  earwig: 42.69,
//  fennec: 'gopher' ]

d.clear()
console.log(d.length)
//0

Refer to the included tests for more example use.