theorem pred_Sn : \forall n:nat.
(eq nat n (pred (S n))).
-intros.
-apply refl_equal.
+intros.reflexivity.
qed.
theorem injective_S : \forall n,m:nat.
(eq nat (S n) (S m)) \to (eq nat n m).
intros.
-(elim (sym_eq ? ? ? (pred_Sn n))).(elim (sym_eq ? ? ? (pred_Sn m))).
+rewrite > pred_Sn n.
+rewrite > pred_Sn m.
apply f_equal. assumption.
qed.
theorem O_S : \forall n:nat. Not (eq nat O (S n)).
intros.simplify.intros.
-cut (not_zero O).exact Hcut.elim (sym_eq ? ? ? H).
+cut (not_zero O).exact Hcut.rewrite > H.
exact I.
qed.
intros.elim n.apply O_S.apply not_eq_S.assumption.
qed.
-
let rec plus n m \def
match n with
[ O \Rightarrow m
| (S p) \Rightarrow S (plus p m) ].
theorem plus_n_O: \forall n:nat. eq nat n (plus n O).
-intros.elim n.simplify.apply refl_equal.simplify.apply f_equal.assumption.
+intros.elim n.simplify.reflexivity.
+simplify.apply f_equal.assumption.
qed.
theorem plus_n_Sm : \forall n,m:nat. eq nat (S (plus n m)) (plus n (S m)).
-intros.elim n.simplify.apply refl_equal.simplify.apply f_equal.assumption.
+intros.elim n.simplify.reflexivity.
+simplify.apply f_equal.assumption.
qed.
theorem sym_plus: \forall n,m:nat. eq nat (plus n m) (plus m n).
intros.elim n.simplify.apply plus_n_O.
-simplify.elim (sym_eq ? ? ? H).apply plus_n_Sm.
+simplify.rewrite > H.apply plus_n_Sm.
qed.
theorem assoc_plus:
\forall n,m,p:nat. eq nat (plus (plus n m) p) (plus n (plus m p)).
-intros.elim n.simplify.apply refl_equal.simplify.apply f_equal.assumption.
+intros.elim n.simplify.reflexivity.
+simplify.apply f_equal.assumption.
qed.
let rec times n m \def
| (S p) \Rightarrow (plus m (times p m)) ].
theorem times_n_O: \forall n:nat. eq nat O (times n O).
-intros.elim n.simplify.apply refl_equal.simplify.assumption.
+intros.elim n.simplify.reflexivity.
+simplify.assumption.
qed.
theorem times_n_Sm :
\forall n,m:nat. eq nat (plus n (times n m)) (times n (S m)).
-intros.elim n.simplify.apply refl_equal.
-simplify.apply f_equal.elim H.
-apply trans_eq ? ? (plus (plus e m) (times e m)).apply sym_eq.
-apply assoc_plus.apply trans_eq ? ? (plus (plus m e) (times e m)).
+intros.elim n.simplify.reflexivity.
+simplify.apply f_equal.rewrite < H.
+transitivity (plus (plus e m) (times e m)).symmetry.
+apply assoc_plus.transitivity (plus (plus m e) (times e m)).
apply f_equal2.
-apply sym_plus.apply refl_equal.apply assoc_plus.
+apply sym_plus.reflexivity.apply assoc_plus.
qed.
theorem sym_times :
\forall n,m:nat. eq nat (times n m) (times m n).
intros.elim n.simplify.apply times_n_O.
-simplify.elim (sym_eq ? ? ? H).apply times_n_Sm.
+simplify.rewrite < sym_eq ? ? ? H.apply times_n_Sm.
qed.
let rec minus n m \def
(\forall n:nat. R O n) \to
(\forall n:nat. R (S n) O) \to
(\forall n,m:nat. R n m \to R (S n) (S m)) \to \forall n,m:nat. R n m.
-intros.cut \forall m:nat.R n m.apply Hcut.elim n.apply H.
-apply nat_case m1.apply H1.intros.apply H2. apply H3.
+intros 5.elim n.apply H.
+apply nat_case m.apply H1.intros.apply H2. apply H3.
qed.
inductive le (n:nat) : nat \to Prop \def
theorem le_n_O_eq : \forall n:nat. (le n O) \to (eq nat O n).
intros.cut (le n O) \to (eq nat O n).apply Hcut. assumption.
-elim n.apply refl_equal.
+elim n.reflexivity.
apply False_ind.apply (le_Sn_O ? H2).
qed.
theorem le_S_n : \forall n,m:nat. le (S n) (S m) \to le n m.
-intros.cut le (pred (S n)) (pred (S m)).exact Hcut.
+intros.change with le (pred (S n)) (pred (S m)).
elim H.apply le_n.apply trans_le ? (pred x).assumption.
apply le_pred_n.
qed.
apply nat_double_ind (\lambda n,m.((le n m) \to (le m n) \to eq nat n m)).
intros.whd.intros.
apply le_n_O_eq.assumption.
-intros.whd.intros.apply sym_eq.apply le_n_O_eq.assumption.
-intros.whd.intros.apply f_equal.apply H2.
+intros.symmetry.apply le_n_O_eq.assumption.
+intros.apply f_equal.apply H2.
apply le_S_n.assumption.
apply le_S_n.assumption.
qed.
eq compare (nat_compare n m) (compare_invert (nat_compare m n)).
intros.
apply nat_double_ind (\lambda n,m.eq compare (nat_compare n m) (compare_invert (nat_compare m n))).
-intros.elim n1.simplify.apply refl_equal.
-simplify.apply refl_equal.
-intro.elim n1.simplify.apply refl_equal.
-simplify.apply refl_equal.
-intros.simplify.elim H.apply refl_equal.
+intros.elim n1.simplify.reflexivity.
+simplify.reflexivity.
+intro.elim n1.simplify.reflexivity.
+simplify.reflexivity.
+intros.simplify.elim H.simplify.reflexivity.
qed.