Question

I need to edit the function which locates inside of the constructor.
Example:

some.thing = function() {
    this.somefn = function() { // this is the function that I need to fix
        ...
    }
}

But function should be edited not just only for a single object (new obj = some.thing();) but also for any created objects by this constructor.

So is there any way to edit such inner-functions?

Answer 1

Here is a solution based on prototype:

var Something = function () {
    this.f = function () {
       console.log("Something");
    };    
};
var Old = Something;
var Something = function () {
    Old.apply(this);
    this.f = function () {
        console.log("New");
    };
};
Something.prototype = new Old();

var s = new Something();
s.f(); // prints "New"