docs: function on(ev, fn, context){
      var arg = arguments;
      var slice = [].slice;
      var evs = ev.split(',');
      var i = 0;
      var evt = '';
      var __fn = fn;
      fn = function wrapOn(e){
        context = context || this;
        __fn.apply(context, [e].concat(slice.call(arg, 3)));
      };
  
      while(evs[i]){
        evt = evs[i].replace(TRIM_REG, '');
        if (evt) Events.prototype.on.call(this, evt, fn);
        i++;
      }
  
      return fn;
    }