Generic Event Emitter

EventEmitter.js

module.exports = function() {
  var handlers = {};

  function _register(name) {
    return handlers[name] || handlers[name] = [];
  }

  function on(name, handler) {
    var event = _register(name);
    event.push(handler);
  }
  
  function off(name, handler) {
    var event, index;
    event = _register(name);
    index = event.indexOf(handler);
    if(index > -1) {
      event.splice(index, 1);
    }
  }
  
  function emit(name, data) {
    var args, events, index;
    args = [].slice.call(arguments, 1);
    events = _register(name);
    for(index = 0; index < events.length; index++) {
      events[i].apply(events[i], args);
    }
  }

  return {
    on: on,
    off: off,
    emit: emit
  }
};