jQuery.fn.hasBind.js

jQuery.fn.hasBind = function(type, _fn)
{
  var data, eventsMap, events;
  
  if(!((data = this._data()) && (eventsMap = data.events) && (events = eventsMap[type])))
    return false;
    
  var event, i = -1; while((event = events[++i]) && event.handler !== _fn)
    ;
    
  return !!event;  
};