Compiler Error C2885

'class::identifier' : not a valid using-declaration at non-class scope

Remarks

You used a using declaration incorrectly.

This error can be generated as a result of compiler conformance work that was done for Visual Studio 2005: it is no longer valid to have a using declaration to a nested type; you must explicitly qualify each reference you make to the nested type, put the type in a namespace, or create a typedef.

Examples

The following example generates C2885.

// C2885.cpp
namespace MyNamespace {
   class X1 {};
}

struct MyStruct {
   struct X1 {
      int i;
   };
};

int main () {
   using MyStruct::X1;   // C2885

   // OK
   using MyNamespace::X1;
   X1 myX1;

   MyStruct::X1 X12;

   typedef MyStruct::X1 abc;
   abc X13;
   X13.i = 9;
}

If you use the using keyword with a class member, C++ requires you to define that member inside another class (a derived class).

The following example generates C2885.

// C2885_b.cpp
// compile with: /c
class A {
public:
   int i;
};

void z() {
   using A::i;   // C2885 not in a class
}

class B : public A {
public:
   using A::i;
};