Why can't I multi-declare a class

Question

I can do this

extern int i;
extern int i;

But I can\'t do the same with a class

class A {
..
}
class A {
..
}

Answer 1

But in the first case ther is no contradiction.

extern int i;
extern double i;

won't work either. So if you create class A to times it wouldn't be possible to decide who A is.