//----------------------------------------------------------------------
// bool.h - declaration for a bool type
//
//  This is about the most portable way to define a bool type.  It
//  relies only on C syntax.  It works better than a C++ enum because
//  the <, >, and == operators return type int, and you get warnings
//  about conversions if you try to assign to a bool type variable.
//  This fixes the warnings, at the cost of some type checking ability.
//
//  WARNING: be careful when using expressions like:
//  
//  if (BooleanFunction() == true) ...
//
//  since true is defined to be exactly 1, it is possible for 
//  the BooleanFunction to return some other non-zero value, which
//  should be true, but which is not == 1.  It is safer to just say
//  
//  if (BooleanFunction()) ...
//
//
//  HOW TO USE THIS FILE:
//
//  This file should work on any compiler.  You should be able to say
//
//  #include "bool.h"
//
//  and this file will figure out how to define the bool type for you,
//  even if "defining the bool type" means allowing the builtin type
//  to be used.  If this file does not work for your compiler, please
//  email me (Andy, acollins@cs.washington.edu) and tell me about it.
//
//  You don't need to know how this file works, but if you are curious,
//  you should be able to figure it out by looking at the comments
//  and probably a C preprocessor reference.
//
//  Andy Collins   --   CSE 143 Computer Programming II 
//  Unversity of Washington Computer Science and EngineeringCSE 143
//  Last update: 02 October 1997
//----------------------------------------------------------------------

#ifndef _BOOL_H_     // Standard multiple-inclusion boilerplate
#define _BOOL_H_

// the following code identifies all forms of MS C, and disables
// the warning that says you shouldn't be using bool, true and false
// Unfortunately, it also knocks off all other warnings about using
// features which are reserved.  Oh well
//                     -- Andy
#ifdef _MSC_VER
#if (_MSC_VER < 1100)         // older than 5.0
#pragma warning(disable:4237)
#endif
#endif

// The ifndefs here keep us from doing this under G++, since
// that already has a bool, and under MSVC 5.0 (and hopefully
// any nerwer versions, although the documentation wasn't 
// clear on the future trends of the numbering system.  1100
// means version 5.0)
#define _NEED_TO_DEFINE_BOOL 1    // Assume we have to define it

#ifdef __GNUC__        // find and handle G++
#undef _NEED_TO_DEFINE_BOOL
#define _NEED_TO_DEFINE_BOOL 0
#endif

#ifdef _MSC_VER           // find and handle MSVC 5.0
#if (_MSC_VER >= 1100)    // MSVC older than 5.0
#undef _NEED_TO_DEFINE_BOOL
#define _NEED_TO_DEFINE_BOOL 0
#endif
#endif

#ifdef __MWERKS__        // find and handle Metrowerks CodeWarrior
 #if (__MWERKS__ != 1)   // if we're running CW7 or later...
  #if __option (bool)    // and bool support is active...
   #undef _NEED_TO_DEFINE_BOOL   // then we don't need the hack
   #define _NEED_TO_DEFINE_BOOL 0
  #endif
 #endif
#endif

#if (_NEED_TO_DEFINE_BOOL == 1)
enum {false = 0, true = 1};     // this gives us true and false
typedef int bool;               // this gives us bool
#endif

#endif // _BOOL_H_