writer.hh

    
#ifndef already_included_writer_hh
#define already_included_writer_hh

// GENERAL-PURPOSE OUTPUT ROUTINES...
// The operator << is used for output
// for both built-in and user-defined types.
// For built-in types, the functions are
// defined here.  For user-defined types,
// functions are defined in the appropriate
// classes.

class string;

ABSTRACT class Writer
{
public:
   virtual ~Writer() {}
   virtual Writer& operator << (char ch)       = null;
   virtual Writer& operator << (int i)         = null;
   virtual Writer& operator << (double d)      = null;
   virtual Writer& operator << (const char* s) = null;
};
Writer& operator<<(Writer& w,bool b);

final class File_Writer : public Writer
{
private:
   FILE* f;
   bool ours_to_close;
public:
   File_Writer(string file_name);
   File_Writer(const char* file_name);
   File_Writer(FILE* f);
   ~File_Writer();
   Writer& operator << (char ch);
   Writer& operator << (int i);
   Writer& operator << (double d);
   Writer& operator << (const char* s);
};

extern File_Writer cout;
extern File_Writer cerr;
extern File_Writer debug;
const char endl = '\n';

#endif /* already_included_writer_hh */