将一个名称空间隐藏在另一个名称空间中

Question

I need to use one namespace inside another and i don't want to allow access to the first namespace in the way like this

namespace One
{
    typedef int INT;
}

namespace Two
{
    using namespace One;
    #include "file.h"
    ...
}

int main(void)
{
    Two::INT i;
}

file.h

namespace One 
{
    INT k;
}

I can't change file.h that is why i need using inside Two and i need user be forced to use this notation:

int main(void)
{
    Two::One::INT i;
}

Such notation is mandatory, because in file.hi redefine types from One with another pragma and if user ask for same type with Two::type_name and Two::One::type_name it would get structures with different memory layouts.

Yes, Two::One::k must be accessible.

Answer 1

// Namespaces can be nested where you can define one namespace inside another name space as follows:

namespace namespace_name1 {
   // code declarations
   namespace namespace_name2 {
      // code declarations
   }
}

//You can access members of nested namespace by using resultion operators as follows:

// to access members of namespace_name2

using namespace namespace_name1::namespace_name2;

// to access members of namespace:name1

using namespace namespace_name1;

// http://www.tutorialspoint.com/cplusplus/cpp_namespaces.htm