Why doesn't this work when the function is a static method?

[Jack via Digitalmars-d-learn]

works fine (this is defined at global scope, g and baa are same 
as static)

    int f(HWND hwnd, int n)
    {
        return n*10;
    }

    void baa()
    {
        HWND foo;
        writeln(foo.f(10));
    }


but if I wrap this within a class:

class Foo
{
    static int f(HWND hwnd, int n)
    {
        return n*10;
    }


    static void baa()
    {
        HWND foo;
        writeln(foo.f(10));
    }
}

I get the error:

Error: no property f for type void*