adding callback to function - always

Question

I found myself using a weird way to add callback functions to my functions and I was wondering if there is a more generic way to add callbacks to functions, best case I would ha

Answer 1

You could, if you really want to, extend Function.prototype with a .cb prototype. Something like:

Function.prototype.cb = function(cb){
   var self = this;
   return function(){
      self.callback = cb || function(){};
      self.apply(self, arguments);
   }
}

then your code would compress to:

var myFunc = function(obj){
   // some code

   this.callback(); // callback will always be defined
}

and the call would slightly change:

myFunc.cb(function(){
   // callback code
})(myObj);

Just an idea. You can make the syntax pretty much whatever you want.

Answer 2

Not sure what you are trying to do here, but a way to add a callback that seems more straight forward:

function( obj, callback ) {
   if(callback) {
      callback();
   }
}

Answer 3

I prefer a formal parameter:

var myFunc = function(obj, callback) {
   ...
}

This way it makes it obvious that there is a callback. You also don't have to mess around with the arguments object; you can just check to see if callback is undefined, and then check to see if it is of the appropriate type (Function).