async-watch

AsyncWatch is a small library for watching javascript/node.js objects. It uses Object.defineProperty which makes it compatible with most browsers.

Features

• Asynchronous execution (Changes are triggerd on requestAnimationFrame)
• Nested object watching
• Restoring watchers after objects are destroyed
• No dirty hacks
• Suitable for angular-like frameworks
• Good test coverage

Install

For browser:

bower install async-watch --save

For Node.js projects

npm install async-watch --save

Examples

var watch = require('async-watch').AsyncWatch; // not needed for browsers
var obj = {}; // creating an empty object
AsyncWatch(obj, 'a.b.c', function(value){
    console.log('set', value);
});
// You can pass an array as well
//AsyncWatch(obj, ['a', 'b', 'c'])

As you can see here, we start with an empty object. AsyncWatch will set a watcher on property "a", which knows about its descendands

 obj.a = {
  b : {
   c : 1
  }
 };
 obj.a.b.c = 2;
 obj.a.b.c = 3;

The output will look like this:

set undefined
set 3

First set happens when AsyncWatch is initialized, after that the program waits for the next available frame to trigger changes.

Contribution

Contribution is greatly appreciated! Please, run tests before submitting a pool request.

Known issues

https://github.com/wiresjs/async-watch/blob/master/test/corner_case.js#L54