How to look at the implementation of internal methods in JavaScript?

Question

JavaScript

alert(Array.join);//undefined
var x= Array.join;
alert(x)//undefined

So what is the way to see the code of the methods? Is it possible?

Answer 1

Yes. Look for the source code of the engine (Gecko, Webkit) and the corresponding implementation of the method. Through the console - no way.
Example for Gecko: https://github.com/mozilla/gecko-dev/blob/d18a5a08...

Answer 2

alert(Array.join.toString() )?

Answer 3

It is possible to esteem specifications, algorithms for all methods are described there.