Where can i find the code source of javascript functions?

Question

For example, i want to know how the querySelector method was built. I checked on MDN but there's only examples that show how to use it.

I also tried to check in the console.log but nothing readable.

Pal Kerecsenyi · Accepted Answer · 2018-06-05T15:15:54.673

0

There is a non-standard method to do this. Please be aware that it is not fully cross-browser compatible and shouldn't be used in a production environment.

function hello(){
    return "Hi!";
}
console.log(hello.toSource());

See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/toSource for more.

Edit: To see the source code of a built-in function, you will need to look at the engine source. This varies browser to browser. For example, Chrome uses the V8 engine. See https://github.com/v8/v8

edited Jun 05 '18 at 15:15

answered Jun 05 '18 at 15:12

Pal Kerecsenyi

560
4
18

1

I think the OP wants to see the source code of native javascript functions. – Guillaume Georges Jun 05 '18 at 15:13
1

... which just shows up as `function() { [native code] }`. – Carcigenicate Jun 05 '18 at 15:15

Where can i find the code source of javascript functions?

1 Answers1