// Oldham, Jeffrey D.
// 2000Feb21
// CS1321

// Example of Conditional Compilation

// This one piece of code produces two different programs depending on 
// whether you tell the compiler that "DEBUG" is defined.  If it is
// not defined, the debugging code will not be part of the program.
// If it is defined, the debugging code will be part of the program.

// To define "DEBUG", you must compile with a command like
//		g++ -DDEBUG debug.cc
// Following the "-D" is the term you want to define.
// Using "g++ debug.cc" will cause the debugging code to be omitted.

#include <iostream.h>
#include <stdlib.h>		// has EXIT_SUCCESS

int main()
{
  cout << "Hello, world.\n";
#if defined(DEBUG)
  // Note the syntax.  Lines starting with "#" must appear on lines by 
  // themselves and delimit the region of code that is conditionally
  // included.
  cout << "This debugging message is printed only during debugging.\n";
#endif  
  cout << "Hello, world.\n";
  return EXIT_SUCCESS;
}