observ-varlist

An observable list that can grow negatively or positively

Install

$ npm install --save observ-varlist

Usage

var ObservList = require('observ-varlist')
var toArray = require('observ-varlist/to-array')

var list = ObservList(['b', 'c'])

list.prepend('a')

list.from() // => -1
list.count() // => 3

list() // => {from: -1, count: 3, '-1': 'a', 0: 'b', 1: 'c'}
toArray(list) // => ObservArray(['a', 'b', 'c'])
toArray(list()) // => ['a', 'b', 'c']

API

ObservList([initial], [constructor]) -> observList

initial

Optional Type: object|array

Either an array, or an object containing from: Number, count: Number, and optional indices containing data between from and from + count.

constructor

Optional Type: function

Every item put into the list will go through this constructor. Whatever the constructor returns will be stored in the list.

observList Instance

Returned from the ObservList constructor, this is an observable with the following methods:

list.prepend(item)

• Expands the list backwards and inserts the item. Can go into negative indexes.

list.append(item)

• Expands the list forwards and inserts the item.

list.reset(data)

Resets the list. Data is either an array or an object containing from: Number, count: Number, and optional indices containing data between from and from + count.

list.forEach, list.map, list.filter, list.find

Convenience functions that are like the array methods.

License

MIT © Andrew Joslin