Tiniest, simplest pubsub ever

pubsub.js

/*jslint nomen: true*/
'use strict';

var Pubsub = function () {
    this._events = {};
};

Pubsub.prototype.on = function (type, handler) {
    if (this._events[type] === undefined) {
        this._events[type] = [];
    }

    this._events[type].push(handler);
};

Pubsub.prototype.trigger = function (event, message) {
    var events;

    if (this._events[event] instanceof Array) {
        events = this._events[event];
        events.forEach(function (e) {
            e.call(this, message);
        });

    }
};

Pubsub.prototype.off = function (type) {
    if (this._events[type]) {
        delete this._events[type];
    }
};

// ---------------------------------------- //

var broker = new Pubsub();

broker.on('foo', function (m) {
    console.log('Got the message ', m);
});

broker.trigger('foo', 42);
broker.trigger('foo', 26);

broker.off('foo');

broker.trigger('foo', 'Never show this');

// ---------------------------------------- //