1.js

function TodoVM(model){
	this.title = observable(model.title);
	this.completed = observable(model.observable)
}

filters = {
	all: () => true,
	active: (todo) => !todo.completed(),
	completed: (todo) => todo.completed()
};

function TodosVM(todos){
	todos = todos.map((model) => new TodoVM(model)));

	this.todos = observableArray(todos);

	this.todos.bind(JSON.stringify)
		.subscribe(apply(localStorage, 'todos'));

	this.status = computed(function(params){
		return maybe(params.status).orElse('all').value().toLowerCase();
	}, routeStream('/:status?'));

	this.filtered = computed(function(todos, status){
		return todos.filter(filters[status]);
	}, this.todos, this.status);
}

2.js

function TodoVM(model){
	this.title = observable(model.title);
	this.completed = observable(model.observable)
}

filters = {
	all: () => true,
	active: (todo) => !todo.completed(),
	completed: (todo) => todo.completed()
};

function TodosVM(todos){
	todos = todos.map((model) => new TodoVM(model)));

	this.todos = observableArray(todos);

	this.todos.bind(JSON.stringify)
		.subscribe(apply(localStorage, 'todos'));

	this.status = routeStream('/:status?')
		.bind(pluck('status'))
		.bind((status) => maybe(status).orElse('all').value().toLowerCase());

	this.filtered = merge(this.todos, this.status)
		.bind(function(todos, status){
			return todos.filter(filters[status]);
		});
}