obtain the object type within the prototype function

Does anyone know how to retrieve the type of an object under the prototype property? For example, consider the following code:

Object.prototype.someproperty = function(){
...do something...
console.log(typeof this); 
..more...
}

In my code, "Function" always results because the constructor of objects is a function. When I call it like this:

Array.someproperty(); //In this case, I want to get "array"
//or
String.someproperty(); //In this case, I want to get "string"

Instead of getting "function", I want to retrieve "Array"... Does anyone have a solution for this?

Answer №1

The issue at hand is that the reference to this when accessed via Array and String becomes bound to the function itself rather than an instance of the respective types. To identify which of these functions is being called, one must resort to manual testing as shown below:

Object.prototype.someproperty = function() {
  if (this === Array) {
    return "array";
  } else if (this === String) {
    return "string";
  } 
  ...
}

However, in this scenario, you are not accurately determining the type of object from which the prototype is being invoked. The returned value of "function" serves as more of a heuristic rather than a precise type test.

Answer №2

After dedicating a considerable amount of time to reading and learning, I have come to realize the negative consequences of extending prototype objects. Thank you to everyone for your encouragement and assistance.

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