From 41dcb1603ea2e212a9167918f3d5dcb6f166e27b Mon Sep 17 00:00:00 2001 From: herbelin Date: Sat, 18 Oct 2008 15:55:00 +0000 Subject: Expérience de simplification de Ndigits compte tenu des tactiques existant actuellement MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@11466 85f007b7-540e-0410-9357-904b9bb8a0f7 --- theories/NArith/Ndigits.v | 287 ++++++++++++++++++++++------------------------ 1 file changed, 134 insertions(+), 153 deletions(-) (limited to 'theories/NArith') diff --git a/theories/NArith/Ndigits.v b/theories/NArith/Ndigits.v index 04f454df4..633f82edb 100644 --- a/theories/NArith/Ndigits.v +++ b/theories/NArith/Ndigits.v @@ -52,8 +52,8 @@ Proof. destruct n; destruct n'; simpl; auto. generalize p0; clear p0; induction p as [p Hrecp| p Hrecp| ]; simpl; auto. - destruct p0; simpl; trivial; intros; rewrite Hrecp; trivial. - destruct p0; simpl; trivial; intros; rewrite Hrecp; trivial. + destruct p0; trivial; rewrite Hrecp; trivial. + destruct p0; trivial; rewrite Hrecp; trivial. destruct p0 as [p| p| ]; simpl; auto. Qed. @@ -115,7 +115,7 @@ Definition xorf (f g:nat -> bool) (n:nat) := xorb (f n) (g n). Lemma xorf_eq : forall f f', eqf (xorf f f') (fun n => false) -> eqf f f'. Proof. - unfold eqf, xorf. intros. apply xorb_eq. apply H. + unfold eqf, xorf. intros. apply xorb_eq, H. Qed. Lemma xorf_assoc : @@ -166,14 +166,12 @@ Lemma Nbit_faithful_3 : (forall p':positive, eqf (Nbit (Npos p)) (Nbit (Npos p')) -> p = p') -> eqf (Nbit (Npos (xO p))) (Nbit a) -> Npos (xO p) = a. Proof. - destruct a. intros. cut (eqf (Nbit N0) (Nbit (Npos (xO p)))). + destruct a; intros. cut (eqf (Nbit N0) (Nbit (Npos (xO p)))). intro. rewrite (Nbit_faithful_1 (Npos (xO p)) H1). reflexivity. unfold eqf. intro. unfold eqf in H0. rewrite H0. reflexivity. - case p. intros. absurd (false = true). discriminate. - exact (H0 0). - intros. rewrite (H p0 (fun n => H0 (S n))). reflexivity. - intros. absurd (false = true). discriminate. - exact (H0 0). + destruct p. discriminate (H0 O). + rewrite (H p (fun n => H0 (S n))). reflexivity. + discriminate (H0 0). Qed. Lemma Nbit_faithful_4 : @@ -181,27 +179,26 @@ Lemma Nbit_faithful_4 : (forall p':positive, eqf (Nbit (Npos p)) (Nbit (Npos p')) -> p = p') -> eqf (Nbit (Npos (xI p))) (Nbit a) -> Npos (xI p) = a. Proof. - destruct a. intros. cut (eqf (Nbit N0) (Nbit (Npos (xI p)))). + destruct a; intros. cut (eqf (Nbit N0) (Nbit (Npos (xI p)))). intro. rewrite (Nbit_faithful_1 (Npos (xI p)) H1). reflexivity. - unfold eqf. intro. unfold eqf in H0. rewrite H0. reflexivity. - case p. intros. rewrite (H p0 (fun n:nat => H0 (S n))). reflexivity. - intros. absurd (true = false). discriminate. - exact (H0 0). - intros. absurd (N0 = Npos p0). discriminate. + intro. rewrite H0. reflexivity. + destruct p. rewrite (H p (fun n:nat => H0 (S n))). reflexivity. + discriminate (H0 0). cut (eqf (Nbit (Npos 1)) (Nbit (Npos (xI p0)))). - intro. exact (Nbit_faithful_1 (Npos p0) (fun n:nat => H1 (S n))). - unfold eqf in *. intro. rewrite H0. reflexivity. + intro. discriminate (Nbit_faithful_1 (Npos p0) (fun n:nat => H1 (S n))). + intro. rewrite H0. reflexivity. Qed. Lemma Nbit_faithful : forall a a':N, eqf (Nbit a) (Nbit a') -> a = a'. Proof. destruct a. exact Nbit_faithful_1. - induction p. intros a' H. apply Nbit_faithful_4. intros. cut (Npos p = Npos p'). - intro. inversion H1. reflexivity. - exact (IHp (Npos p') H0). + induction p. intros a' H. apply Nbit_faithful_4. intros. + assert (Npos p = Npos p') by exact (IHp (Npos p') H0). + inversion H1. reflexivity. assumption. - intros. apply Nbit_faithful_3. intros. cut (Npos p = Npos p'). intro. inversion H1. reflexivity. - exact (IHp (Npos p') H0). + intros. apply Nbit_faithful_3. intros. + assert (Npos p = Npos p') by exact (IHp (Npos p') H0). + inversion H1. reflexivity. assumption. exact Nbit_faithful_2. Qed. @@ -216,40 +213,37 @@ Qed. Lemma Nxor_sem_2 : forall a':N, Nbit (Nxor (Npos 1) a') 0 = negb (Nbit a' 0). Proof. - intro. case a'. trivial. - simpl. intro. - case p; trivial. + intro. destruct a'. trivial. + destruct p; trivial. Qed. Lemma Nxor_sem_3 : forall (p:positive) (a':N), Nbit (Nxor (Npos (xO p)) a') 0 = Nbit a' 0. Proof. - intros. case a'. trivial. - simpl. intro. - case p0; trivial. intro. - case (Pxor p p1); trivial. - intro. case (Pxor p p1); trivial. + intros. destruct a'. trivial. + simpl. destruct p0; trivial. + destruct (Pxor p p0); trivial. + destruct (Pxor p p0); trivial. Qed. Lemma Nxor_sem_4 : forall (p:positive) (a':N), Nbit (Nxor (Npos (xI p)) a') 0 = negb (Nbit a' 0). Proof. - intros. case a'. trivial. - simpl. intro. case p0; trivial. intro. - case (Pxor p p1); trivial. - intro. - case (Pxor p p1); trivial. + intros. destruct a'. trivial. + simpl. destruct p0; trivial. + destruct (Pxor p p0); trivial. + destruct (Pxor p p0); trivial. Qed. Lemma Nxor_sem_5 : forall a a':N, Nbit (Nxor a a') 0 = xorf (Nbit a) (Nbit a') 0. Proof. - destruct a. intro. change (Nbit a' 0 = xorb false (Nbit a' 0)). rewrite false_xorb. trivial. - case p. exact Nxor_sem_4. - intros. change (Nbit (Nxor (Npos (xO p0)) a') 0 = xorb false (Nbit a' 0)). - rewrite false_xorb. apply Nxor_sem_3. exact Nxor_sem_2. + destruct a; intro. change (Nbit a' 0 = xorb false (Nbit a' 0)). rewrite false_xorb. trivial. + destruct p. apply Nxor_sem_4. + change (Nbit (Nxor (Npos (xO p)) a') 0 = xorb false (Nbit a' 0)). + rewrite false_xorb. apply Nxor_sem_3. apply Nxor_sem_2. Qed. Lemma Nxor_sem_6 : @@ -258,28 +252,29 @@ Lemma Nxor_sem_6 : forall a a':N, Nbit (Nxor a a') (S n) = xorf (Nbit a) (Nbit a') (S n). Proof. - intros. + intros. +(* pose proof (fun p1 p2 => H (Npos p1) (Npos p2)) as H'. clear H. rename H' into H.*) generalize (fun p1 p2 => H (Npos p1) (Npos p2)); clear H; intro H. unfold xorf in *. - case a. simpl Nbit; rewrite false_xorb. reflexivity. - case a'; intros. + destruct a as [|p]. simpl Nbit; rewrite false_xorb. reflexivity. + destruct a' as [|p0]. simpl Nbit; rewrite xorb_false. reflexivity. - case p0. case p; intros; simpl Nbit in *. - rewrite <- H; simpl; case (Pxor p2 p1); trivial. - rewrite <- H; simpl; case (Pxor p2 p1); trivial. + destruct p. destruct p0; simpl Nbit in *. + rewrite <- H; simpl; case (Pxor p p0); trivial. + rewrite <- H; simpl; case (Pxor p p0); trivial. rewrite xorb_false. reflexivity. - case p; intros; simpl Nbit in *. - rewrite <- H; simpl; case (Pxor p2 p1); trivial. - rewrite <- H; simpl; case (Pxor p2 p1); trivial. + destruct p0; simpl Nbit in *. + rewrite <- H; simpl; case (Pxor p p0); trivial. + rewrite <- H; simpl; case (Pxor p p0); trivial. rewrite xorb_false. reflexivity. - simpl Nbit. rewrite false_xorb. simpl. case p; trivial. + simpl Nbit. rewrite false_xorb. destruct p0; trivial. Qed. Lemma Nxor_semantics : forall a a':N, eqf (Nbit (Nxor a a')) (xorf (Nbit a) (Nbit a')). Proof. - unfold eqf. intros. generalize a a'. elim n. exact Nxor_sem_5. - exact Nxor_sem_6. + unfold eqf. intros; generalize a, a'. induction n. + apply Nxor_sem_5. apply Nxor_sem_6; assumption. Qed. (** Consequences: @@ -289,8 +284,8 @@ Qed. Lemma Nxor_eq : forall a a':N, Nxor a a' = N0 -> a = a'. Proof. - intros. apply Nbit_faithful. apply xorf_eq. apply eqf_trans with (f' := Nbit (Nxor a a')). - apply eqf_sym. apply Nxor_semantics. + intros. apply Nbit_faithful, xorf_eq. apply eqf_trans with (f' := Nbit (Nxor a a')). + apply eqf_sym, Nxor_semantics. rewrite H. unfold eqf. trivial. Qed. @@ -298,19 +293,17 @@ Lemma Nxor_assoc : forall a a' a'':N, Nxor (Nxor a a') a'' = Nxor a (Nxor a' a''). Proof. intros. apply Nbit_faithful. - apply eqf_trans with - (f' := xorf (xorf (Nbit a) (Nbit a')) (Nbit a'')). - apply eqf_trans with (f' := xorf (Nbit (Nxor a a')) (Nbit a'')). + apply eqf_trans with (xorf (xorf (Nbit a) (Nbit a')) (Nbit a'')). + apply eqf_trans with (xorf (Nbit (Nxor a a')) (Nbit a'')). apply Nxor_semantics. apply eqf_xorf. apply Nxor_semantics. apply eqf_refl. - apply eqf_trans with - (f' := xorf (Nbit a) (xorf (Nbit a') (Nbit a''))). + apply eqf_trans with (xorf (Nbit a) (xorf (Nbit a') (Nbit a''))). apply xorf_assoc. - apply eqf_trans with (f' := xorf (Nbit a) (Nbit (Nxor a' a''))). + apply eqf_trans with (xorf (Nbit a) (Nbit (Nxor a' a''))). apply eqf_xorf. apply eqf_refl. - apply eqf_sym. apply Nxor_semantics. - apply eqf_sym. apply Nxor_semantics. + apply eqf_sym, Nxor_semantics. + apply eqf_sym, Nxor_semantics. Qed. (** Checking whether a number is odd, i.e. @@ -370,18 +363,16 @@ Qed. Lemma Nxor_bit0 : forall a a':N, Nbit0 (Nxor a a') = xorb (Nbit0 a) (Nbit0 a'). Proof. - intros. rewrite <- Nbit0_correct. rewrite (Nxor_semantics a a' 0). - unfold xorf. rewrite Nbit0_correct. rewrite Nbit0_correct. reflexivity. + intros. rewrite <- Nbit0_correct, (Nxor_semantics a a' 0). + unfold xorf. rewrite Nbit0_correct, Nbit0_correct. reflexivity. Qed. Lemma Nxor_div2 : forall a a':N, Ndiv2 (Nxor a a') = Nxor (Ndiv2 a) (Ndiv2 a'). Proof. intros. apply Nbit_faithful. unfold eqf. intro. - rewrite (Nxor_semantics (Ndiv2 a) (Ndiv2 a') n). - rewrite Ndiv2_correct. - rewrite (Nxor_semantics a a' (S n)). - unfold xorf. rewrite Ndiv2_correct. rewrite Ndiv2_correct. + rewrite (Nxor_semantics (Ndiv2 a) (Ndiv2 a') n), Ndiv2_correct, (Nxor_semantics a a' (S n)). + unfold xorf. rewrite 2! Ndiv2_correct. reflexivity. Qed. @@ -389,8 +380,9 @@ Lemma Nneg_bit0 : forall a a':N, Nbit0 (Nxor a a') = true -> Nbit0 a = negb (Nbit0 a'). Proof. - intros. rewrite <- true_xorb. rewrite <- H. rewrite Nxor_bit0. - rewrite xorb_assoc. rewrite xorb_nilpotent. rewrite xorb_false. reflexivity. + intros. + rewrite <- true_xorb, <- H, Nxor_bit0, xorb_assoc, xorb_nilpotent, xorb_false. + reflexivity. Qed. Lemma Nneg_bit0_1 : @@ -410,10 +402,9 @@ Lemma Nsame_bit0 : forall (a a':N) (p:positive), Nxor a a' = Npos (xO p) -> Nbit0 a = Nbit0 a'. Proof. - intros. rewrite <- (xorb_false (Nbit0 a)). cut (Nbit0 (Npos (xO p)) = false). - intro. rewrite <- H0. rewrite <- H. rewrite Nxor_bit0. rewrite <- xorb_assoc. - rewrite xorb_nilpotent. rewrite false_xorb. reflexivity. - reflexivity. + intros. rewrite <- (xorb_false (Nbit0 a)). + assert (H0: Nbit0 (Npos (xO p)) = false) by reflexivity. + rewrite <- H0, <- H, Nxor_bit0, <- xorb_assoc, xorb_nilpotent, false_xorb. reflexivity. Qed. (** a lexicographic order on bits, starting from the lowest bit *) @@ -434,42 +425,40 @@ Lemma Nbit0_less : forall a a', Nbit0 a = false -> Nbit0 a' = true -> Nless a a' = true. Proof. - intros. elim (Ndiscr (Nxor a a')). intro H1. elim H1. intros p H2. unfold Nless in |- *. - rewrite H2. generalize H2. elim p. intros. simpl in |- *. rewrite H. rewrite H0. reflexivity. - intros. cut (Nbit0 (Nxor a a') = false). intro. rewrite (Nxor_bit0 a a') in H5. - rewrite H in H5. rewrite H0 in H5. discriminate H5. - rewrite H4. reflexivity. - intro. simpl in |- *. rewrite H. rewrite H0. reflexivity. - intro H1. cut (Nbit0 (Nxor a a') = false). intro. rewrite (Nxor_bit0 a a') in H2. - rewrite H in H2. rewrite H0 in H2. discriminate H2. - rewrite H1. reflexivity. + intros. destruct (Ndiscr (Nxor a a')) as [(p,H2)|H1]. unfold Nless. + rewrite H2. destruct p. simpl. rewrite H, H0. reflexivity. + assert (H1: Nbit0 (Nxor a a') = false) by (rewrite H2; reflexivity). + rewrite (Nxor_bit0 a a'), H, H0 in H1. discriminate H1. + simpl. rewrite H, H0. reflexivity. + assert (H2: Nbit0 (Nxor a a') = false) by (rewrite H1; reflexivity). + rewrite (Nxor_bit0 a a'), H, H0 in H2. discriminate H2. Qed. Lemma Nbit0_gt : forall a a', Nbit0 a = true -> Nbit0 a' = false -> Nless a a' = false. Proof. - intros. elim (Ndiscr (Nxor a a')). intro H1. elim H1. intros p H2. unfold Nless in |- *. - rewrite H2. generalize H2. elim p. intros. simpl in |- *. rewrite H. rewrite H0. reflexivity. - intros. cut (Nbit0 (Nxor a a') = false). intro. rewrite (Nxor_bit0 a a') in H5. - rewrite H in H5. rewrite H0 in H5. discriminate H5. - rewrite H4. reflexivity. - intro. simpl in |- *. rewrite H. rewrite H0. reflexivity. - intro H1. unfold Nless in |- *. rewrite H1. reflexivity. + intros. destruct (Ndiscr (Nxor a a')) as [(p,H2)|H1]. unfold Nless. + rewrite H2. destruct p. simpl. rewrite H, H0. reflexivity. + assert (H1: Nbit0 (Nxor a a') = false) by (rewrite H2; reflexivity). + rewrite (Nxor_bit0 a a'), H, H0 in H1. discriminate H1. + simpl. rewrite H, H0. reflexivity. + assert (H2: Nbit0 (Nxor a a') = false) by (rewrite H1; reflexivity). + rewrite (Nxor_bit0 a a'), H, H0 in H2. discriminate H2. Qed. Lemma Nless_not_refl : forall a, Nless a a = false. Proof. - intro. unfold Nless in |- *. rewrite (Nxor_nilpotent a). reflexivity. + intro. unfold Nless. rewrite (Nxor_nilpotent a). reflexivity. Qed. Lemma Nless_def_1 : forall a a', Nless (Ndouble a) (Ndouble a') = Nless a a'. Proof. - simple induction a. simple induction a'. reflexivity. + destruct a; destruct a'. reflexivity. trivial. - simple induction a'. unfold Nless in |- *. simpl in |- *. elim p; trivial. - unfold Nless in |- *. simpl in |- *. intro. case (Pxor p p0). reflexivity. + unfold Nless. simpl. destruct p; trivial. + unfold Nless. simpl. destruct (Pxor p p0). reflexivity. trivial. Qed. @@ -477,10 +466,10 @@ Lemma Nless_def_2 : forall a a', Nless (Ndouble_plus_one a) (Ndouble_plus_one a') = Nless a a'. Proof. - simple induction a. simple induction a'. reflexivity. + destruct a; destruct a'. reflexivity. trivial. - simple induction a'. unfold Nless in |- *. simpl in |- *. elim p; trivial. - unfold Nless in |- *. simpl in |- *. intro. case (Pxor p p0). reflexivity. + unfold Nless. simpl. destruct p; trivial. + unfold Nless. simpl. destruct (Pxor p p0). reflexivity. trivial. Qed. @@ -500,79 +489,71 @@ Qed. Lemma Nless_z : forall a, Nless a N0 = false. Proof. - simple induction a. reflexivity. - unfold Nless in |- *. intro. rewrite (Nxor_neutral_right (Npos p)). elim p; trivial. + induction a. reflexivity. + unfold Nless. rewrite (Nxor_neutral_right (Npos p)). induction p; trivial. Qed. Lemma N0_less_1 : forall a, Nless N0 a = true -> {p : positive | a = Npos p}. Proof. - simple induction a. intro. discriminate H. - intros. split with p. reflexivity. + destruct a. discriminate. + intros. exists p. reflexivity. Qed. Lemma N0_less_2 : forall a, Nless N0 a = false -> a = N0. Proof. - simple induction a. trivial. - unfold Nless in |- *. simpl in |- *. - cut (forall p:positive, Nless_aux N0 (Npos p) p = false -> False). - intros. elim (H p H0). - simple induction p. intros. discriminate H0. - intros. exact (H H0). - intro. discriminate H. + induction a as [|p]; intro H. trivial. + elimtype False. induction p as [|p IHp|]; discriminate || simpl; auto using IHp. Qed. Lemma Nless_trans : forall a a' a'', Nless a a' = true -> Nless a' a'' = true -> Nless a a'' = true. Proof. - intro a. pattern a; apply N_ind_double. - intros. case_eq (Nless N0 a''). trivial. - intro H1. rewrite (N0_less_2 a'' H1) in H0. rewrite (Nless_z a') in H0. discriminate H0. - intros a0 H a'. pattern a'; apply N_ind_double. - intros. rewrite (Nless_z (Ndouble a0)) in H0. discriminate H0. - intros a1 H0 a'' H1. rewrite (Nless_def_1 a0 a1) in H1. - pattern a''; apply N_ind_double; clear a''. - intro. rewrite (Nless_z (Ndouble a1)) in H2. discriminate H2. - intros. rewrite (Nless_def_1 a1 a2) in H3. rewrite (Nless_def_1 a0 a2). - exact (H a1 a2 H1 H3). - intros. apply Nless_def_3. - intros a1 H0 a'' H1. pattern a''; apply N_ind_double. - intro. rewrite (Nless_z (Ndouble_plus_one a1)) in H2. discriminate H2. - intros. rewrite (Nless_def_4 a1 a2) in H3. discriminate H3. - intros. apply Nless_def_3. - intros a0 H a'. pattern a'; apply N_ind_double. - intros. rewrite (Nless_z (Ndouble_plus_one a0)) in H0. discriminate H0. - intros. rewrite (Nless_def_4 a0 a1) in H1. discriminate H1. - intros a1 H0 a'' H1. pattern a''; apply N_ind_double. - intro. rewrite (Nless_z (Ndouble_plus_one a1)) in H2. discriminate H2. - intros. rewrite (Nless_def_4 a1 a2) in H3. discriminate H3. - rewrite (Nless_def_2 a0 a1) in H1. intros. rewrite (Nless_def_2 a1 a2) in H3. - rewrite (Nless_def_2 a0 a2). exact (H a1 a2 H1 H3). + induction a as [|a IHa|a IHa] using N_ind_double; intros a' a'' H H0. + destruct (Nless N0 a'') in *. trivial. + rewrite (N0_less_2 a'' Heqb), (Nless_z a') in H0. discriminate H0. + induction a' as [|a' _|a' _] using N_ind_double. + rewrite (Nless_z (Ndouble a)) in H. discriminate H. + rewrite (Nless_def_1 a a') in H. + induction a'' using N_ind_double. + rewrite (Nless_z (Ndouble a')) in H0. discriminate H0. + rewrite (Nless_def_1 a' a'') in H0. rewrite (Nless_def_1 a a''). + exact (IHa _ _ H H0). + apply Nless_def_3. + induction a'' as [|a'' _|a'' _] using N_ind_double. + rewrite (Nless_z (Ndouble_plus_one a')) in H0. discriminate H0. + rewrite (Nless_def_4 a' a'') in H0. discriminate H0. + apply Nless_def_3. + induction a' as [|a' _|a' _] using N_ind_double. + rewrite (Nless_z (Ndouble_plus_one a)) in H. discriminate H. + rewrite (Nless_def_4 a a') in H. discriminate H. + induction a'' using N_ind_double. + rewrite (Nless_z (Ndouble_plus_one a')) in H0. discriminate H0. + rewrite (Nless_def_4 a' a'') in H0. discriminate H0. + rewrite (Nless_def_2 a' a'') in H0. rewrite (Nless_def_2 a a') in H. + rewrite (Nless_def_2 a a''). exact (IHa _ _ H H0). Qed. Lemma Nless_total : forall a a', {Nless a a' = true} + {Nless a' a = true} + {a = a'}. Proof. - intro a. - pattern a; apply N_rec_double; clear a. - intro. case_eq (Nless N0 a'). intro H. left. left. auto. - intro H. right. rewrite (N0_less_2 a' H). reflexivity. - intros a0 H a'. - pattern a'; apply N_rec_double; clear a'. - case_eq (Nless N0 (Ndouble a0)). intro H0. left. right. auto. - intro H0. right. exact (N0_less_2 _ H0). - intros a1 H0. rewrite Nless_def_1. rewrite Nless_def_1. elim (H a1). intro H1. - left. assumption. - intro H1. right. rewrite H1. reflexivity. - intros a1 H0. left. left. apply Nless_def_3. - intros a0 H a'. - pattern a'; apply N_rec_double; clear a'. - left. right. case a0; reflexivity. - intros a1 H0. left. right. apply Nless_def_3. - intros a1 H0. rewrite Nless_def_2. rewrite Nless_def_2. elim (H a1). intro H1. - left. assumption. - intro H1. right. rewrite H1. reflexivity. + induction a using N_rec_double; intro a'. + destruct (Nless N0 a') in *. left. left. auto. + right. rewrite (N0_less_2 a' Heqb). reflexivity. + induction a' as [|a' _|a' _] using N_rec_double. + destruct (Nless N0 (Ndouble a)) in *. left. right. auto. + right. exact (N0_less_2 _ Heqb). + rewrite 2!Nless_def_1. destruct (IHa a') as [ | ->]. + left. assumption. + right. reflexivity. + left. left. apply Nless_def_3. + induction a' as [|a' _|a' _] using N_rec_double. + left. right. destruct a; reflexivity. + left. right. apply Nless_def_3. + rewrite 2!Nless_def_2. destruct (IHa a') as [ | ->]. + left. assumption. + right. reflexivity. Qed. (** Number of digits in a number *) @@ -621,7 +602,7 @@ Proof. induction n; intros. rewrite (V0_eq _ bv); simpl; auto. rewrite (VSn_eq _ _ bv); simpl. -generalize (IHn (Vtail _ _ bv)); clear IHn. +specialize IHn with (Vtail _ _ bv). destruct (Vhead _ _ bv); destruct (Bv2N n (Vtail bool n bv)); simpl; auto with arith. @@ -701,7 +682,7 @@ Lemma Nbit0_Blow : forall n, forall (bv:Bvector (S n)), Proof. intros. unfold Blow. -pattern bv at 1; rewrite (VSn_eq _ _ bv). +rewrite (VSn_eq _ _ bv) at 1. simpl. destruct (Bv2N n (Vtail bool n bv)); simpl; destruct (Vhead bool n bv); auto. @@ -750,9 +731,9 @@ Lemma Nxor_BVxor : forall n (bv bv' : Bvector n), Proof. induction n. intros. -rewrite (V0_eq _ bv); rewrite (V0_eq _ bv'); simpl; auto. +rewrite (V0_eq _ bv), (V0_eq _ bv'); simpl; auto. intros. -rewrite (VSn_eq _ _ bv); rewrite (VSn_eq _ _ bv'); simpl; auto. +rewrite (VSn_eq _ _ bv), (VSn_eq _ _ bv'); simpl; auto. rewrite IHn. destruct (Vhead bool n bv); destruct (Vhead bool n bv'); destruct (Bv2N n (Vtail bool n bv)); destruct (Bv2N n (Vtail bool n bv')); simpl; auto. -- cgit v1.2.3