//Purpose: to see if certain kinds of statements compile.
//The compiler seems to err where "+++" text is found, below.
//From _The C++ Programming Language_, 3rd ed., Stroustrup, p. 228, section
//"10.2.4 Static Members:"
//"... a [design] that preserves the semantics of default constructor 
values"
//... "without the encumbrance of a publicly accessible global variable."
//Tested on platform DJGPP ver. 2.03 using compiler G++ ver. 2.953 by 
default
//"tuned for Pentium" on an Intel 386 running Windows 95 ver. 4.00.950.
//Author: George Sawyer (address@hidden).
//Date: July 19, 2001.

#include <iostream>

#define SHOW_ERROR

//Class to test compiler.
class AAA
{private:
   int data1;
   int data2;

   //Default value: data member declaration.
   static AAA defaultValue;
public:
   //Constructor declaration, with its own defaults.
   AAA ( const int & d1 = 0, const int & d2 = 0 );

   //Set default value: member function declaration.
#ifdef SHOW_ERROR
   //Error (1) calling this, when function was void.
   static void setDefault ( const int & e1, const int & e2 );
#else
   //Solution was to use:
   static int setDefault ( const int & e1, const int & e2 );
#endif
   //Obtain object values: member function declarations.
   int out1 ( ) const;
   int out2 ( ) const;
};
//Constructor definition, with its own defaults.
AAA::AAA ( const int & d1 = 0, const int & d2 = 0 )
{  //If values not supplied, use stored defaults.
   data1 = d1 ? d1 : defaultValue.data1;
   data2 = d2 ? d2 : defaultValue.data2;
}
//Set default value: member function definition.
#ifdef SHOW_ERROR
//Error (1) calling this, when function was void.
void AAA::setDefault ( const int & e1, const int & e2 )
#else
//Solution was to use:
int AAA::setDefault ( const int & e1, const int & e2 )
#endif
{  defaultValue = AAA ( e1, e2 );
#ifndef SHOW_ERROR
   return 0;
#endif
}
//Obtain object values: member function definitions.
int AAA::out1 ( ) const {  return data1; }
int AAA::out2 ( ) const {  return data2; }

//----End of class definitions.----------------------------------------

//Define and initialize default value: use constructor, abbreviated form.
AAA AAA::defaultValue ( 10, 11 );

//Obtain default value: use constructor, normal form.
AAA var1 = AAA ( );

//Generate particular value: use constructor, normal form.
AAA var2 = AAA ( 20, 21 );

//Generate particular value: use constructor, abbreviated form.
AAA var3 ( 30, 31 );

//Using appropriate member function, set new default value.
#ifdef SHOW_ERROR
//+++Error (1) here, for some reason. Compiler says:
//+++ANSI C++ forbids declaration `setDefault' with no type.
//+++`int AAA::setDefault' is not a static member of 'class AAA'.
//+++initializer list being treated as compound expression.
AAA::setDefault ( 40, 41 );
#else
//Solution was to use:
int n = AAA::setDefault ( 40, 41 );
#endif

//Obtain default value: use constructor, abbreviated form.
#ifdef SHOW_ERROR
//+++Error (2) below, for some reason. Compiler says:
//+++Request for member `out1' in `var4', which is of non-aggregate type
//+++`AAA ()()'.
//+++(Same for out2.)
AAA var4 ( );
#else
//Solution was to use normal form:
AAA var4 = AAA ( );
#endif

int main ( )
{  cout << "var1 is " << var1.out1 ( ) << ", " << var1.out2 ( ) << ".\n";
   cout << "var2 is " << var2.out1 ( ) << ", " << var2.out2 ( ) << ".\n";
   cout << "var3 is " << var3.out1 ( ) << ", " << var3.out2 ( ) << ".\n";
   //+++Error (2) here, explained above.
   cout << "var4 is " << var4.out1 ( ) << ", " << var4.out2 ( ) << ".\n";
}