--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* ********************************************************************** *)
+(* Progetto FreeScale *)
+(* *)
+(* Sviluppato da: *)
+(* Cosimo Oliboni, oliboni@cs.unibo.it *)
+(* *)
+(* Questo materiale fa parte della tesi: *)
+(* "Formalizzazione Interattiva dei Microcontroller a 8bit FreeScale" *)
+(* *)
+(* data ultima modifica 15/11/2007 *)
+(* ********************************************************************** *)
+
+include "freescale/theory.ma".
+include "freescale/bool.ma".
+
+(* ******** *)
+(* BOOLEANI *)
+(* ******** *)
+
+ndefinition boolRelation : Type → Type ≝
+λA:Type.A → A → bool.
+
+ndefinition boolSymmetric: ∀A:Type.∀R:boolRelation A.Prop ≝
+λA.λR.∀x,y:A.R x y = R y x.
+
+ntheorem bool_destruct_true_false : true ≠ false.
+ nnormalize;
+ #H;
+ nchange with (match true with [ true ⇒ False | false ⇒ True]);
+ nrewrite > H;
+ nnormalize;
+ napply I.
+nqed.
+
+ntheorem bool_destruct_false_true : false ≠ true.
+ nnormalize;
+ #H;
+ nchange with (match true with [ true ⇒ False | false ⇒ True]);
+ nrewrite < H;
+ nnormalize;
+ napply I.
+nqed.
+
+nlemma bsymmetric_eqbool : boolSymmetric bool eq_bool.
+ nnormalize;
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ napply (refl_eq ??).
+nqed.
+
+nlemma bsymmetric_andbool : boolSymmetric bool and_bool.
+ nnormalize;
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ napply (refl_eq ??).
+nqed.
+
+nlemma bsymmetric_orbool : boolSymmetric bool or_bool.
+ nnormalize;
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ napply (refl_eq ??).
+nqed.
+
+nlemma bsymmetric_xorbool : boolSymmetric bool xor_bool.
+ nnormalize;
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ napply (refl_eq ??).
+nqed.
+
+nlemma eqbool_to_eq : ∀b1,b2:bool.(eq_bool b1 b2 = true) → (b1 = b2).
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##2,3: nelim (bool_destruct_false_true H) ##]
+ napply (refl_eq ??).
+nqed.
+
+nlemma eq_to_eqbool : ∀b1,b2.b1 = b2 → eq_bool b1 b2 = true.
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##2: nelim (bool_destruct_true_false H)
+ ##| ##3: nelim (bool_destruct_false_true H) ##]
+ napply (refl_eq ??).
+nqed.
+
+nlemma andb_true_true: ∀b1,b2.(b1 ⊗ b2) = true → b1 = true.
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##3,4: nelim (bool_destruct_false_true H) ##]
+ napply (refl_eq ??).
+nqed.
+
+nlemma andb_true_true_r: ∀b1,b2.(b1 ⊗ b2) = true → b2 = true.
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##2,3,4: nelim (bool_destruct_false_true H) ##]
+ napply (refl_eq ??).
+nqed.
+
+nlemma orb_false_false : ∀b1,b2:bool.(b1 ⊕ b2) = false → b1 = false.
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##1,2: nelim (bool_destruct_true_false H) ##]
+ napply (refl_eq ??).
+nqed.
+
+nlemma orb_false_false_r : ∀b1,b2:bool.(b1 ⊕ b2) = false → b2 = false.
+ #b1; #b2;
+ nelim b1;
+ nelim b2;
+ nnormalize;
+ #H;
+ ##[ ##1,3: nelim (bool_destruct_true_false H) ##]
+ napply (refl_eq ??).
+nqed.