Fork channel

Create a new channel as a copy of main.

Rename channel

Rename main to:

Delete channel

Delete main? This cannot be undone.

using-decl-a.h
typedef int using_decl_type;
int using_decl_var;
int merged;

namespace UsingDecl {
  using ::using_decl_type;
  using ::using_decl_var;

  namespace A { typedef int inner; }
  using A::inner;
}