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Overloading operator << to accept template function

I am trying to write extensible grammar using functions, but cannot find the correct syntax for accepting a template function. I use Visual C ++ 2008. It will accept a variable of the same type as a template function, or a similar function without a template, but not the template function itself.

Error 1 of error C2679: binary '<<: an operator was not found that accepts the right operand of the "overloaded function" type (or there is no acceptable conversion) (string ***)

class Grammar {
    friend Grammar operator << ( const Grammar& lhs, const char* rhs ) {
        return lhs; // append rhs to grammar
    }
    template<typename T>
    friend Grammar operator << ( const Grammar& lhs, T (*rhs) () ) {
        return lhs; // append rhs() to grammar
    }
};

template<typename T>
class ExpressionParticle {
};

template<typename T>
ExpressionParticle<T> Expression () ;

ExpressionParticle<int> ExpressionInt ();

int _tmain ( int argc, _TCHAR *argv[] )
{
    ExpressionParticle<int> (*p)();

    p = Expression<int>;

    Grammar() << "p";
    Grammar() << p;
    Grammar() << ExpressionInt;
    Grammar() << Expression<int>; // ***

What is the type Expression<int>if it is not type p in the above? How its type differs from type ExpressionInt.

+5
4

, g++ . Visual Studio. , VS2005 . ( VS2005):

template<class T>
T id(T t)  {return t; }
int main ()
{
    ExpressionParticle<int> (*p)();

    p = Expression<int>;

    Grammar() << "p";
    Grammar() << p;
    Grammar() << ExpressionInt;
    Grammar() << id(Expression<int>); // ***
}
+3

:

class Grammar {
    friend Grammar operator << ( const Grammar& lhs, const char* rhs ) {
        return lhs; // append rhs to grammar
    }
    template<typename T>
    friend Grammar operator << ( const Grammar& lhs, T (*rhs) () ) {
        return lhs; // append rhs() to grammar
    }
};

:

class Grammar {
public:
    Grammar& operator << ( const char* rhs ) {
        return *this; // append rhs to grammar
    }
    template<typename T>
    Grammar& operator << ( const T &rhs) {
        return *this; // append rhs() to grammar
    }
};
0

VS2010 . typedef . VS2008, , .

int _tmain ( int argc, _TCHAR *argv[] )
{
   typedef ExpressionParticle< int > (*FCN)();

   ExpressionParticle<int> (*p)() = Expression<int>; 

   Grammar() << "p"; 
   Grammar() << p; 
   Grammar() << ExpressionInt; 
   Grammar() << static_cast< FCN >( Expression<int> );
0

MSVC 2013 , ++ 11, :

template <typename T>
using Fptr = ExpressionParticle<T>(*)();

:

Grammar() << Fptr<int>(Expression<int>) << endl;
0

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