#ifndef _BOOL_H_
#define _BOOL_H_

/* Note: It is an abstraction violation to use the C "boolean"
 * operators (&&, ||, etc.) on Bool objects.  Those operators
 * really operate on type "int".
 *
 * Note: Bool_and() and Bool_or() do not short circuit.
 * Bool_cand() and Bool_cor() do.  
 */ 

/* The identifier en_Bool and the values are private */

#ifdef Bool
#undef Bool
#endif

#ifdef __STDC__
typedef enum Bool_en {Bool_FALSE=0, Bool_TRUE=1} Bool;
#else
typedef int Bool;
#define Bool_FALSE 0
#define Bool_TRUE  1
#endif

/* The macro expansions are private */

#define Bool_to_int(a) ((int)a)
#define Bool_to_char(a) ((char)a)
#define Bool_create(integral_value) (((integral_value) != 0)?(Bool_TRUE):(Bool_FALSE))
/* Some type conversions are omitted for efficiency (with stupid compilers) */
#define Bool_or(a,b) ((a)|(b))
#define Bool_and(a,b) ((a)&(b))
#define Bool_cor(a,b) ((a)||(b))
#define Bool_cand(a,b) ((a)&&(b))
#define Bool_not(a) ((a)^(Bool_TRUE))

#endif