how to determine source information of callback in

问题:

Is it possible to determine the source information (file, line number, column number) of a callback in v8?

function foo(callback) {
    var x = callback();
    if (typeof x !== "string") {
        //hmmm, x is not as expected, I want to know more about the callback.
    }
}

回答1:

I'm not aware that you can do this in JavaScript, but if you can debug it, it should show you the file/line etc..

I guess doing that would depend exactly on your setup and I've never done it myself - it looks like node (uses v8) has some sort of support for that .

Might be useful?: v8 DebuggerProtocol

回答2:

callsite helps with this.

It exposes __stack global variable which can be used to get the stack trace. And __line which is the current line number.