Renaming built in javascript functions

Question

Can one rename a built in JavaScript function?

I am trying to rename the "reverse" function to another name, but still have it do the same function

Answer 1

You can change the name by creating an alias in the prototype for the function

 Array.prototype.newreversename = Array.prototype.reverse; var arr=["abc","sssd"]; console.log(arr.newreversename())

You can also create a wrapper function for the new function

 Array.prototype.newreversefunction = function() { return this.reverse(); }; var arr=["a","c"]; console.log(arr.newreversefunction())

Answer 2

You can, but don't

This is called monkey patching. Javascript is flexible enough to allow you to change fundamental things like this, but you will break other code and make your own code unreadable by others if you modify normal parts of the language this way.

That said, you can assign and clear things, even in prototypes like this

Array.prototype.rev = Array.prototype.reverse
> function reverse() { [native code] }
Array.prototype.reverse = null
> null
[1,2,3,4,5].rev()
> [5, 4, 3, 2, 1]
[1,2,3,4,5].reverse()
> "[1,2,3,4,5].reverse is not a function"

Answer 3

You can , but I would strongly recommend against doing so.

The proper way to do it would be to get the property descriptor for the method from the prototype ( Object.getOwnPropertyDescriptor ), then use that to define a new property ( Object.defineProperty ), and use delete to get rid of the previous one:

 Object.defineProperty( Array.prototype, "thingy", Object.getOwnPropertyDescriptor(Array.prototype, "reverse") ); delete Array.prototype.reverse; console.log([1,2,3].thingy()); // [3, 2, 1] console.log([1,2,3].reverse()); // Error

Answer 4

You can do it like this:

Array.prototype.myReverse = Array.prototype.reverse;
delete Array.prototype.reverse;

But you should avoid this, as many libraries rely on the reverse function. Instead, if you want to call it using another name, just do the first line:

Array.prototype.myReverse = Array.prototype.reverse;

Answer 5

You can change the name by creating an alias

 Array.prototype.slicing = Array.prototype.slice; var animals = ['ant', 'bison', 'camel', 'duck', 'elephant']; console.log(animals.slicing(2))