X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fcontribs%2FRELATIONAL%2FNPlus%2Finv.ma;h=99bf3a9eeaa07b3a99d4048b73fdfc15b35065c3;hb=b0b69bb764af48d7f022477398f0beff5fb3f3f3;hp=68043c84a6ab65e66512910dcf46f5a0b356eab5;hpb=00f8f919262e3c84dd9e42477092cc1312171493;p=helm.git

diff --git a/matita/contribs/RELATIONAL/NPlus/inv.ma b/matita/contribs/RELATIONAL/NPlus/inv.ma
index 68043c84a..99bf3a9ee 100644
--- a/matita/contribs/RELATIONAL/NPlus/inv.ma
+++ b/matita/contribs/RELATIONAL/NPlus/inv.ma
@@ -16,119 +16,78 @@ set "baseuri" "cic:/matita/RELATIONAL/NPlus/inv".
 
 include "NPlus/defs.ma".
 
-(* primitive generation lemmas proved by elimination and inversion *)
+(* Inversion lemmas *********************************************************)
 
-theorem nplus_gen_zero_1: \forall q,r. (zero + q == r) \to q = r.
- intros. elim H; clear H q r; intros;
- [ reflexivity
- | clear H1. auto new timeout=30
- ].
+theorem nplus_inv_zero_1: \forall q,r. (zero + q == r) \to q = r.
+ intros. elim H; clear H q r; auto.
 qed.
 
-theorem nplus_gen_succ_1: \forall p,q,r. ((succ p) + q == r) \to 
+theorem nplus_inv_succ_1: \forall p,q,r. ((succ p) + q == r) \to 
                           \exists s. r = (succ s) \land p + q == s.
  intros. elim H; clear H q r; intros;
- [
- | clear H1.
-   decompose.
-   subst.
- ]; apply ex_intro; [| auto new timeout=30 || auto new timeout=30 ]. (**)
+ [ auto depth = 4
+ | clear H1. decompose. subst. auto depth = 4
+ ]
 qed.
 
-theorem nplus_gen_zero_2: \forall p,r. (p + zero == r) \to p = r.
+theorem nplus_inv_zero_2: \forall p,r. (p + zero == r) \to p = r.
  intros. inversion H; clear H; intros;
- [ auto new timeout=30
- | clear H H1.
-   destruct H2.
+ [ auto.
+ | clear H H1. destruct H2.
  ].
 qed.
 
-theorem nplus_gen_succ_2: \forall p,q,r. (p + (succ q) == r) \to 
+theorem nplus_inv_succ_2: \forall p,q,r. (p + (succ q) == r) \to 
                           \exists s. r = (succ s) \land p + q == s.
  intros. inversion H; clear H; intros;
  [ destruct H.
- | clear H1 H3 r.
-   destruct H2; clear H2.
-   subst.
-   apply ex_intro; [| auto new timeout=30 ] (**)
+ | clear H1 H3 r. destruct H2; clear H2. subst. auto depth = 4.
  ].
 qed.
 
-theorem nplus_gen_zero_3: \forall p,q. (p + q == zero) \to 
+theorem nplus_inv_zero_3: \forall p,q. (p + q == zero) \to 
                           p = zero \land q = zero.
  intros. inversion H; clear H; intros;
- [ subst. auto new timeout=30
- | clear H H1.
-   destruct H3.
+ [ subst. auto
+ | clear H H1. destruct H3.
  ].
 qed.
 
-theorem nplus_gen_succ_3: \forall p,q,r. (p + q == (succ r)) \to
+theorem nplus_inv_succ_3: \forall p,q,r. (p + q == (succ r)) \to
                           \exists s. p = succ s \land (s + q == r) \lor
                                      q = succ s \land p + s == r.
  intros. inversion H; clear H; intros;
- [ subst.
- | clear H1.
-   destruct H3. clear H3.
-   subst.
- ]; apply ex_intro; [| auto new timeout=30 || auto new timeout=30 ] (**)
+ [ subst
+ | clear H1. destruct H3. clear H3. subst.
+ ]; auto depth = 4.
 qed.
-(*
-(* alternative proofs invoking nplus_gen_2 *)
 
-variant nplus_gen_zero_3_alt: \forall p,q. (p + q == zero) \to 
-                              p = zero \land q = zero.
- intros 2. elim q; clear q; intros;
- [ lapply linear nplus_gen_zero_2 to H as H0.
-   subst. auto new timeout=30
- | clear H.
-   lapply linear nplus_gen_succ_2 to H1 as H0.
-   decompose.
-   lapply linear eq_gen_zero_succ to H1 as H0. apply H0
- ].
-qed.
+(* Corollaries to inversion lemmas ******************************************)
 
-variant nplus_gen_succ_3_alt: \forall p,q,r. (p + q == (succ r)) \to
-                              \exists s. p = succ s \land (s + q == r) \lor
-                                         q = succ s \land p + s == r.
- intros 2. elim q; clear q; intros;
- [ lapply linear nplus_gen_zero_2 to H as H0.
-   subst
- | clear H.
-   lapply linear nplus_gen_succ_2 to H1 as H0.
-   decompose.
-   lapply linear eq_gen_succ_succ to H1 as H0.
-   subst
- ]; apply ex_intro; [| auto new timeout=30 || auto new timeout=30 ]. (**)
+theorem nplus_inv_succ_2_3: \forall p,q,r.
+                            (p + (succ q) == (succ r)) \to p + q == r.
+ intros. 
+ lapply linear nplus_inv_succ_2 to H. decompose. subst.
+ destruct H1. clear H1. subst. auto.
 qed.
-*)
-(* other simplification lemmas *)
 
-theorem nplus_gen_eq_2_3: \forall p,q. (p + q == q) \to p = zero.
- intros 2. elim q; clear q; intros;
- [ lapply linear nplus_gen_zero_2 to H as H0.
-   subst
- | lapply linear nplus_gen_succ_2 to H1 as H0.
-   decompose.
-   destruct H2. clear H2.
-   subst
- ]; auto new timeout=30.
+theorem nplus_inv_succ_1_3: \forall p,q,r.
+                            ((succ p) + q == (succ r)) \to p + q == r.
+ intros. 
+ lapply linear nplus_inv_succ_1 to H. decompose. subst.
+ destruct H1. clear H1. subst. auto.
 qed.
 
-theorem nplus_gen_eq_1_3: \forall p,q. (p + q == p) \to q = zero.
- intros 1. elim p; clear p; intros;
- [ lapply linear nplus_gen_zero_1 to H as H0.
-   subst
- | lapply linear nplus_gen_succ_1 to H1 as H0.
-   decompose.
-   destruct H2. clear H2.
-   subst
- ]; auto new timeout=30.
+theorem nplus_inv_eq_2_3: \forall p,q. (p + q == q) \to p = zero.
+ intros 2. elim q; clear q;
+ [ lapply linear nplus_inv_zero_2 to H
+ | lapply linear nplus_inv_succ_2_3 to H1
+ ]; auto.
 qed.
 
-theorem nplus_gen_succ_2_3: \forall p,q,r.
-                            (p + (succ q) == (succ r)) \to p + q == r.
- intros. 
- lapply linear nplus_gen_succ_2 to H. decompose. subst.
- destruct H1. clear H1. subst. auto.
+theorem nplus_inv_eq_1_3: \forall p,q. (p + q == p) \to q = zero.
+ intros 1. elim p; clear p;
+ [ lapply linear nplus_inv_zero_1 to H
+ | lapply linear nplus_inv_succ_1_3 to H1.
+ ]; auto.
 qed.