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Compiler Error C3161


The latest version of this topic can be found at 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.

The following sample generates C3161.

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