Immuo NPM | npm.io

ImmuO

Immutable objects in JavaScript

Installation

Via npm on Node:

npm install immuo

In your browser: TBD

Usage

Reference in your program

var immuo = require('immuo');

Reference in your browser TBD

Create an immutable object:

var state = immuo();

Setting a property returns the new immutable object:

var newstate = state.set('name', 'Adam');
console.log(newstate.name); // 'Adam'
console.log(state.name); // undefined

Setting a property (nested or not) returns the new top immutable object

var state = immuo();
var newstate = state.set('person', {});
newstate = newstate.person.set('name', 'Adam');
newstate = newstate.person.set('age', 800);

console.log(newstate.person.name); // 'Adam'
console.log(newstate.person.age);  // 800

The properties are immutable:

var state = immuo();
var newstate = state.set('person', {});
newstate.person = { name: 'Adam' }; // invalid operation!!!

You can get a cloned detached object, and modify it:

var state1 = immuo();
var state2 = state1.set('person', {});

// cloned and detached person
var person = state2.person.get();

// now, each set returns a new person, not a new state
var newperson = person.set('name', 'Adam')
    .set('age', 800)
    .set('wife', 'Eve');
    
// attach to state
var state3 = state2.set('person', newperson);