Example of Compose.expand in action which is related to https://github.com/iaincarsberg/compose/commit/59e5b9a96b28642279636ec7f6ee15087cf6d29e

main.js

Entity = Compose(
	function () {
		// fake a unique id
		this.id = Math.floor(Math.random() * 1000);
	},
	{
		a: function () {
			return this.id;
		}
	}
);

// Add some functionality to the Entity
Entity.expand(Compose(
	function (custom) {
		this.name = (custom || {}).name || 'unknown';
	},
	{
		getName: function () {
			return this.name + ' is entity ' + this.id;
		}
	}
));


var e1 = new Entity({name: 'Iain'}),
	e2 = new Entity({name: 'Carsberg'}),
	e3 = new Entity();

console.log(e1.id, e1.a(), e1.getName());// 918 918 "Iain is entity 918"
console.log(e2.id, e2.a(), e2.getName());// 919 919 "Carsberg is entity 919"
console.log(e3.id, e3.a(), e3.getName());// 895 895 "unknown is entity 895"