A minimal Redux clone.

mux.js

module.exports = Object.freeze({



	createSelector: function (selector, processor) {
		var cache = {}, processed;
		return function (state) {
			var selected = selector(state);
			if (selected !== cache) {
				processed = processor(selected);
				cache = selected;
			}
			return processed;
		};
	},



	createStore: function (state, reducer) {
		var listeners = [];
		return {

			state: function () { return state; },

			dispatch: function (action) {
				var newState = reducer(state, action);
				if (newState !== state) {
					state = newState;
					for (var i = 0; i < listeners.length; i++) {
						listeners[i](state);
					}
				}
			},

			subscribe: function (listener) {
				listeners.push(listener);
				return this;
			}

		};
	},



	upstream: function (store, app, handlers) {
		Object.keys(handlers).forEach(function (key) {
			app[key] = handlers[key].bind(store.dispatch);
		});
	},



	downstream: function (store, app, handlers) {
		var keys = Object.keys(handlers);
		store.subscribe(function (state) {
			keys.forEach(function (key) {
				app[key] = handlers[key](state);
			});
		});
	}



});