// Implement a decorator function that takes
// a function as an argument and will track
// how many times the passed function was called.
function Add(x, y) {
return x + y;
}
var Add = countDecorator(Add);
Add(1, 1);
// -> 2 Dont pay attention to this number. The important part is we called the `Add` function once.
Add.callCount();
// -> 1
Add(2, 2);
// -> 4 Dont pay attention to this number either. The important part is we called the `Add` function again.
Add.callCount();
// -> 2