X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fmatita%2Flibrary%2Fdecidable_kit%2Flist_aux.ma;h=a5bf2edb7588ca139325fa040fb2bf75ac148f3c;hb=8272528f48b942a80024aeb9b625d99cfe3f0f44;hp=8f30d3f6f00fcf13c2226db68f56c433abb84e85;hpb=680039d60c1d69521f84580ee0069cb2d6ff56ba;p=helm.git

diff --git a/helm/software/matita/library/decidable_kit/list_aux.ma b/helm/software/matita/library/decidable_kit/list_aux.ma
index 8f30d3f6f..a5bf2edb7 100644
--- a/helm/software/matita/library/decidable_kit/list_aux.ma
+++ b/helm/software/matita/library/decidable_kit/list_aux.ma
@@ -12,18 +12,11 @@
 (*                                                                        *)
 (**************************************************************************)
 
-set "baseuri" "cic:/matita/decidable_kit/list_aux/".
-
 include "list/list.ma".
 include "decidable_kit/eqtype.ma".
 include "nat/plus.ma".
 
-(* ### some functions on lists (some can be moved to list.ma ### *)
-
-let rec foldr (A,B:Type) (f : A → B → B) (b : B) (l : list A) on l : B := 
-  match l with [ nil ⇒ b | (cons a l) ⇒ f a (foldr ? ? f b l)].
-   
-definition length ≝ λT:Type.λl:list T.foldr T nat (λx,c.S c) O l.
+(* ### some functions on lists ### *)
 
 definition count : ∀T : eqType.∀f : T → bool.∀l : list T. nat :=
   λT:eqType.λf,l. 
@@ -32,38 +25,7 @@ definition count : ∀T : eqType.∀f : T → bool.∀l : list T. nat :=
 let rec mem (d : eqType) (x : d) (l : list d) on l : bool ≝
   match l with
   [ nil ⇒ false 
-  | cons y tl ⇒
-     match (cmp d x y) with [ true ⇒ true | false ⇒ mem d x tl]].
-
-definition iota : nat → nat → list nat ≝
-  λn,m. nat_rect (λ_.list ?) (nil ?) (λx,acc.cons ? (n+x) acc) m.
-  
-let rec map (A,B:Type) (f: A → B) (l : list A) on l : list B ≝
-  match l with [ nil ⇒ nil ? | cons x tl ⇒ f x :: (map A B f tl)].
-
-(* ### induction principle for functions visiting 2 lists in parallel *)
-lemma list_ind2 : 
-  ∀T1,T2:Type.∀l1:list T1.∀l2:list T2.∀P:list T1 → list T2 → Prop.
-  length ? l1 = length ? l2 →
-  (P (nil ?) (nil ?)) → 
-  (∀tl1,tl2,hd1,hd2. P tl1 tl2 → P (hd1::tl1) (hd2::tl2)) → 
-  P l1 l2.
-intros (T1 T2 l1 l2 P Hl Pnil Pcons);
-generalize in match Hl; clear Hl;
-generalize in match l2; clear l2;
-elim l1 1 (l2 x1); [ cases l2; intros (Hl); [assumption| destruct Hl]
-| intros 3 (tl1 IH l2); cases l2; [1: simplify; intros 1 (Hl); destruct Hl] 
-  intros 1 (Hl); apply Pcons;
-  apply IH; destruct Hl; 
-  (* XXX simplify in Hl non folda length *) 
-  assumption;]
-qed.
-  
- 
-lemma eq_map : ∀A,B,f,g,l. (∀x.f x = g x) → map A B f l = map A B g l.
-intros (A B f g l Efg); elim l; simplify; [1: reflexivity ];
-rewrite > (Efg t); rewrite > H; reflexivity;  
-qed.
+  | cons y tl ⇒ orb (cmp d x y) (mem d x tl)].
 
 (* ### eqtype for lists ### *)
 let rec lcmp (d : eqType) (l1,l2 : list d) on l1 : bool ≝
@@ -76,13 +38,12 @@ lemma lcmp_length :
   ∀d:eqType.∀l1,l2:list d.
  lcmp ? l1 l2 = true → length ? l1 = length ? l2.
 intros 2 (d l1); elim l1 1 (l2 x1);
-[ cases l2; simplify; intros;[reflexivity|destruct H] 
-| intros 3 (tl1 IH l2); cases (l2); intros; [1:destruct H]
-  simplify; (* XXX la apply non fa simplify? *) 
-  apply congr_S; apply (IH l);
-  (* XXX qualcosa di enorme e' rotto! la regola di convertibilita?! *)
-  simplify in H;
-  letin H' ≝ (b2pT ? ? (andbP ? ?) H); decompose; assumption]
+[1: cases l2; simplify; intros; [reflexivity|destruct H] 
+|2: intros 3 (tl1 IH l2); cases (l2); intros; [1:simplify in H; destruct H]
+    simplify; (* XXX la apply non fa simplify? *) 
+    apply congr_S; apply (IH l);
+    (* XXX qualcosa di enorme e' rotto! la regola di convertibilita?! *)
+    simplify in H; cases (b2pT ? ? (andbP ? ?) H); assumption]
 qed.
 
 lemma lcmpP : ∀d:eqType.∀l1,l2:list d. eq_compatible (list d) l1 l2 (lcmp d l1 l2).
@@ -90,34 +51,21 @@ intros (d l1 l2);
 generalize in match (refl_eq ? (lcmp d l1 l2));
 generalize in match (lcmp d l1 l2) in ⊢ (? ? ? % → %); intros 1 (c);
 cases c; intros (H); [ apply reflect_true | apply reflect_false ]
-[ letin Hl≝ (lcmp_length ? ? ? H); clearbody Hl;
+[ lapply (lcmp_length ? ? ? H) as Hl;
   generalize in match H; clear H;
   apply (list_ind2 ? ? ? ? ? Hl); [1: intros; reflexivity]
-  simplify; intros (tl1 tl2 hd1 hd2 IH H);
-  letin H' ≝ (b2pT ? ? (andbP ? ?) H); decompose;
+  simplify; intros (tl1 tl2 hd1 hd2 IH H); cases (b2pT ? ? (andbP ? ?) H);
   rewrite > (IH H2); rewrite > (b2pT ? ? (eqP d ? ?) H1); reflexivity
-| generalize in match H; clear H; generalize in match l2; clear l2;
-  elim l1 1 (l1 x1);
-   [ cases l1; [intros; destruct H]
-     unfold Not; intros; destruct H1;
+| elim l1 in H l2 ⊢ % 1 (l1 x1);
+   [ cases l1; simplify; [intros; destruct H | unfold Not; intros; destruct H1;]
    | intros 3 (tl1 IH l2); cases l2;
      [ unfold Not; intros; destruct H1;
      | simplify;  intros;
-       letin H' ≝ (p2bT ? ? (negbP ?) H); clearbody H'; clear H;
-       letin H'' ≝ (b2pT ? ? (andbPF ? ?) H'); clearbody H''; clear H';
-       cases H''; clear H'';
-       [ intros; 
-         letin H' ≝ (b2pF ? ? (eqP d ? ?) H); clearbody H'; clear H;
-         (* XXX destruct H1; *)
-         change in H' with (Not ((match (x1::tl1) with [nil⇒x1|(cons x1 _) ⇒ x1]) = s));
-         rewrite > H1 in H'; simplify in H'; apply H'; reflexivity;
-       | intros; 
-         letin H' ≝ (IH ? H); clearbody H';
-         (* XXX destruct H1 *)
-         change in H' with (Not ((match (x1::tl1) with [nil⇒tl1|(cons _ l) ⇒ l]) = l)); 
-         rewrite > H1 in H'; simplify in H'; apply H'; reflexivity;
-       ]]]]
+       cases (b2pT ? ? (andbPF ? ?) (p2bT ? ? (negbP ?) H)); clear H;
+       [ intro; lapply (b2pF ? ? (eqP d ? ?) H1) as H'; clear H1;
+         destruct H; apply H'; reflexivity;
+       | intro; lapply (IH ? H1) as H'; destruct H;
+         apply H'; reflexivity;]]]]
 qed.
     
 definition list_eqType : eqType → eqType ≝ λd:eqType.mk_eqType ? ? (lcmpP d).  
-