What is the difference between these two custom event binding methods? Which one is better?

var __onfireEvents = {}; function _bind(eventName, callback, is_one, context) { if (typeof eventName !== string_str || typeof callback !== function_str) { throw new Error('args: '+string_str+', '+function_str+''); } if (! hasOwnKey(__onfireEvents, eventName)) { __onfireEvents[eventName] = {}; } __onfireEvents[eventName][++__cnt] = [callback, is_one, context]; return [eventName, __cnt]; } function on(eventName, callback, context) { return _bind(eventName, callback, 0, context); } 

$customSubMap = {}; subscribeEvent = function ( $collection, event_name, fn ) { $collection.on( event_name, fn ); if ( ! $customSubMap[ event_name ] ) { $customSubMap[ event_name ] = $collection; } else { $customSubMap[ event_name ] = $customSubMap[ event_name ].add( $collection ); } };