gistfile1.js

/**
 * @file Description
 */

/**
 * Description
 *
 * @constructor
 */

function EventEmitter(){

}

/**
 * Description
 */

EventEmitter.prototype.initEvents = function(){
    if (this._events) return;

    this._events = {};
    this._all = [];
};

/**
 * Description
 *
 * @param {String} type
 */

EventEmitter.prototype.listeners = function(type){
    this.initEvents();

    var events = this._events[type];
    return events ? events.clone : [];
};

/**
 * Description
 *
 * @param {String} type
 * @param {...} args
 */

EventEmitter.prototype.emit = function(type){
    this.initEvents();

    var listeners = this.listeners(type);
    var self      = this;
    var args      = arguments.toArray.slice(1);

    listeners.each(function(fn){
        fn.apply(self, args);
    });

    this._all.each(function(fn){
        fn.call(self, type, args);
    });

    return this;
};

/**
 * Description
 *
 * @param {String} type
 * @param {Function} fn
 */

EventEmitter.prototype.on = function(type, fn){
    this.initEvents();

    var events = this._events[type] = this._events[type] || [];
    events.push(fn);

    return this;
};

/**
 * Description
 *
 * @param {String} type
 * @param {Function} fn
 */

EventEmitter.prototype.once = function(type, fn){
    var self = this;

    return this.on(type, function(){
        fn.apply(this, arguments);
        self.off(type, fn);
    });
};

/**
 * Description
 *
 * @param {String} [type]
 * @param {Function} fn
 */

EventEmitter.prototype.off = function(type, fn){
    this.initEvents();

    if (!fn) {
        fn = type;
        type = null;
    }

    function check(arr){
        if (!arr) return;
        arr.each(function(val, key){
            if (val === fn) arr.remove(key);
        });
    }

    if (type) {
        check(this._events[type]);
    } else {
        this._events.each(check);
    }

    return this;
};

/**
 * Description
 *
 * @param {Function} fn
 */

EventEmitter.prototype.onAny = function(fn){
    this.initEvents();

    this._all.push(fn);
    return this;
};

/**
 * Description
 *
 * @param {Function} fn
 */

EventEmitter.prototype.offAny = function(fn){
    this.initEvents();

    var all = this._all;

    all.each(function(val, key){
        if (fn === val) all.remove(key);
    });

    return this;
};

/**
 * Description
 *
 * @param {EventEmitter} to
 * @param {String} [namespace]
 */

EventEmitter.prototype.proxy = function(to, namespace){
    this.initEvents();

    var from = this;
    namespace = namespace ? namespace + " " : "";

    from.onAny(function(type, args){
        var listeners = to.listeners(namespace + type);
        listeners.each(function(fn){
            fn.apply(from, args);
        });
    });

    return from;
};

module.exports = EventEmitter;