[removed] is given function empty?

Question

Let\'s have a function call

function doSomethingAndInvokeCallback(callback){
    // do something
    callback();
}

I can check if given arg

Answer 1

In some implementation you can just do a toString() on the function and get it's content. Though it contains comments etcetera.

var foo = function(){ /* Comment */ };
alert(foo.toString());