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Compiler Error C2931

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'class' : type-class-id redefined as a member function of 'identifier'

You can't use a generic or template class as a member function of another class.

This error is obsolete in Visual Studio 2022 and later versions.

This error can be caused if braces are improperly matched.

The following sample generates C2931:

// C2931.cpp
// compile with: /c
template<class T>
struct TC { };
struct MyStruct {
   void TC<int>();   // C2931
};

struct TC2 { };
struct MyStruct2 {
   void TC2();
};

C2931 can also occur when using generics:

// C2931b.cpp
// compile with: /clr /c
generic<class T> ref struct GC {};
struct MyStruct {
   void GC<int>();   // C2931
   void GC2();   // OK
};