Name Space of typedef Names
Names declared using typedef occupy the same name space as other identifiers (except statement labels). Therefore, they cannot use the same identifier as a previously declared name, except in a class-type declaration. Consider the following example:
// typedef_names1.cpp
// C2377 expected
typedef unsigned long UL; // Declare a typedef name, UL.
int UL; // C2377: redefined.
The name-hiding rules that pertain to other identifiers also govern the visibility of names declared using typedef. Therefore, the following example is legal in C++:
// typedef_names2.cpp
typedef unsigned long UL; // Declare a typedef name, UL
int main()
{
unsigned int UL; // Redeclaration hides typedef name
}
// typedef UL back in scope