#include <fstream>  // define class 'ofstream' and 'ostream'

//----------------------------------------------------
template< class T1 >
class TBase {
public:
   TBase( const T1 t ):itsA( t ){}
   ~TBase(){};
   friend ostream& operator<<( ostream& os, const TBase< T1 >& b );
protected:
   T1 itsA;
};

template< class T1 >
ostream& operator<<( ostream& os, const TBase< T1 >& b ){
   os << b.itsA;
   return os;
};

//----------------------------------------------------
template< class T2, class T3 >
class TAdvanced : public TBase< T2 > {
public:
   TAdvanced( const T2 t2, const T3 t3 ) : TBase< T2 >( t2 ), itsB( t3 ){};
   ~TAdvanced(){};
   friend ostream& operator<<( ostream& os, const TAdvanced< T2, T3 >& a );
protected:
   T3 itsB;
};

template< class T2, class T3 >
ostream& operator<<( ostream& os, const TAdvanced< T2, T3 >& a ){
   os << static_cast< TBase< T2 > >( a ) << itsB;
   return os;
};

//----------------------------------------------------
void main( int, char*[] ){
   ofstream ofs( "test.dat", ios::out | ios::binary );
   TAdvanced< int, float > test( 1, 2.3 );
   ofs << test;
};  // End main


In the above code my compiler complains about the line 'ofs << test;',
claiming that there is an ambiguity between
'operator<<( ostream&, const TBase< T1 >& )' and
'operator<<( ostream&, const TAdvanced< T2, T3 >& )'

Isn't it clear that 'test' is of type 'TAdvanced< int, float >' and not
of type 'TBase< int >' ?!!!!!!

Dazed and confused while using BC501.

-Daniel




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