[sv-bc] empty typedefs

The LRM is not clear in the following cases:
 
   Can you have multiple identical empty typedefs of the same typename
in the same scope?
 
ex1:
   typedef class C;
   typedef class C;
 
Ex2:
   typedef C;
   typedef class C;
 
 
I assume that non identical typedefs should be an error:
    typedef enum C;
    typedef class C;
 
 
Also would the following be legal:
 
class C
endclass
 
typedef class C; // looks like it can be legal but it is not much of a
forward declaration!
 
 
Francoise
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