Compiler Error C3161

'interface' : nesting class, struct, union or interface in an interface is illegal; nesting interface in a class, struct or union is illegal

An __interface can only appear at global scope or within a namespace. A class, struct, or union cannot appear in an interface.

Example

The following sample generates C3161.

// C3161.cpp
// compile with: /c
__interface X {
   __interface Y {};   // C3161 A nested interface
};