Compiler Error C2899

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typename cannot be used outside a template declaration

The typename keyword can be used only in a template definition or declaration. In a template declaration, it can be used in two ways:

// C2899.cpp
// compile with: /c
template<typename T> 
class X {};

// Another way
template<class T> 
struct XX {
   typename T::A a;   // T::A is a type
};

The following sample generates C2899:

// C2899b.cpp
// compile with: /c
struct Y {
   typedef int B;
   typename Y::B b;   // C2899
};