javascript: prototyping with multiple objects

Question

Sorry if this is answered somewhere (it probably is), but I'm not quite sure how to even ask it properly, so I failed at searching :(

Basically I want to do something like this:

(a||b).prototype.c = function () {
  // do something
}

Basically a and b are objects. One or the other will exist, but not both. But I don't know which will exist, but I need to add a method to whichever one does.

Now, I know I could do something like this:

if (typeof(a) == 'object') {
  a.prototype.c = c;
} else if (typeof(b) == 'object') {
  b.prototype.c = c;
} 

function c () {
  // do something
}

But this has the problem of c having its own namespace on the global level, and I don't want that. I do not want c to have it's own namespace on the global level at any point in time.

Soo...obviously the first bit of code above doesn't work. How would I go about this? Or is something like this simply not possible? Please feel free to close and point me in the right direction if this has been answered before...

Answer 1

I think something like this will solve your problem:

(function() {
  var f = function() {
    //Prototype function
  };
  if(a)
    a.prototype.f = f;
  if(b)
    b.prototype.f = f;
})();