X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambda_delta%2FGround_2%2Fstar.ma;fp=matita%2Fmatita%2Fcontribs%2Flambda_delta%2FGround_2%2Fstar.ma;h=0000000000000000000000000000000000000000;hb=eb918fc784eacd2094e3986ba321ef47690d9983;hp=ed35806424bbb2c0bca9ae9796fc8a3521eae9a7;hpb=011cf6478141e69822a5b40933f2444d0522532f;p=helm.git diff --git a/matita/matita/contribs/lambda_delta/Ground_2/star.ma b/matita/matita/contribs/lambda_delta/Ground_2/star.ma deleted file mode 100644 index ed3580642..000000000 --- a/matita/matita/contribs/lambda_delta/Ground_2/star.ma +++ /dev/null @@ -1,112 +0,0 @@ -(**************************************************************************) -(* ___ *) -(* ||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 *) -(* *) -(**************************************************************************) - -include "basics/star.ma". -include "Ground_2/xoa_props.ma". -include "Ground_2/notation.ma". - -(* PROPERTIES OF RELATIONS **************************************************) - -definition Decidable: Prop → Prop ≝ λR. R ∨ (R → False). - -definition confluent2: ∀A. ∀R1,R2: relation A. Prop ≝ λA,R1,R2. - ∀a0,a1. R1 a0 a1 → ∀a2. R2 a0 a2 → - ∃∃a. R2 a1 a & R1 a2 a. - -definition transitive2: ∀A. ∀R1,R2: relation A. Prop ≝ λA,R1,R2. - ∀a1,a0. R1 a1 a0 → ∀a2. R2 a0 a2 → - ∃∃a. R2 a1 a & R1 a a2. - -lemma TC_strip1: ∀A,R1,R2. confluent2 A R1 R2 → - ∀a0,a1. TC … R1 a0 a1 → ∀a2. R2 a0 a2 → - ∃∃a. R2 a1 a & TC … R1 a2 a. -#A #R1 #R2 #HR12 #a0 #a1 #H elim H -a1 -[ #a1 #Ha01 #a2 #Ha02 - elim (HR12 … Ha01 … Ha02) -HR12 -a0 /3 width=3/ -| #a #a1 #_ #Ha1 #IHa0 #a2 #Ha02 - elim (IHa0 … Ha02) -a0 #a0 #Ha0 #Ha20 - elim (HR12 … Ha1 … Ha0) -HR12 -a /4 width=3/ -] -qed. - -lemma TC_strip2: ∀A,R1,R2. confluent2 A R1 R2 → - ∀a0,a2. TC … R2 a0 a2 → ∀a1. R1 a0 a1 → - ∃∃a. TC … R2 a1 a & R1 a2 a. -#A #R1 #R2 #HR12 #a0 #a2 #H elim H -a2 -[ #a2 #Ha02 #a1 #Ha01 - elim (HR12 … Ha01 … Ha02) -HR12 -a0 /3 width=3/ -| #a #a2 #_ #Ha2 #IHa0 #a1 #Ha01 - elim (IHa0 … Ha01) -a0 #a0 #Ha10 #Ha0 - elim (HR12 … Ha0 … Ha2) -HR12 -a /4 width=3/ -] -qed. - -lemma TC_confluent2: ∀A,R1,R2. - confluent2 A R1 R2 → confluent2 A (TC … R1) (TC … R2). -#A #R1 #R2 #HR12 #a0 #a1 #H elim H -a1 -[ #a1 #Ha01 #a2 #Ha02 - elim (TC_strip2 … HR12 … Ha02 … Ha01) -HR12 -a0 /3 width=3/ -| #a #a1 #_ #Ha1 #IHa0 #a2 #Ha02 - elim (IHa0 … Ha02) -a0 #a0 #Ha0 #Ha20 - elim (TC_strip2 … HR12 … Ha0 … Ha1) -HR12 -a /4 width=3/ -] -qed. - -lemma TC_strap1: ∀A,R1,R2. transitive2 A R1 R2 → - ∀a1,a0. TC … R1 a1 a0 → ∀a2. R2 a0 a2 → - ∃∃a. R2 a1 a & TC … R1 a a2. -#A #R1 #R2 #HR12 #a1 #a0 #H elim H -a0 -[ #a0 #Ha10 #a2 #Ha02 - elim (HR12 … Ha10 … Ha02) -HR12 -a0 /3 width=3/ -| #a #a0 #_ #Ha0 #IHa #a2 #Ha02 - elim (HR12 … Ha0 … Ha02) -HR12 -a0 #a0 #Ha0 #Ha02 - elim (IHa … Ha0) -a /4 width=3/ -] -qed. - -lemma TC_strap2: ∀A,R1,R2. transitive2 A R1 R2 → - ∀a0,a2. TC … R2 a0 a2 → ∀a1. R1 a1 a0 → - ∃∃a. TC … R2 a1 a & R1 a a2. -#A #R1 #R2 #HR12 #a0 #a2 #H elim H -a2 -[ #a2 #Ha02 #a1 #Ha10 - elim (HR12 … Ha10 … Ha02) -HR12 -a0 /3 width=3/ -| #a #a2 #_ #Ha02 #IHa #a1 #Ha10 - elim (IHa … Ha10) -a0 #a0 #Ha10 #Ha0 - elim (HR12 … Ha0 … Ha02) -HR12 -a /4 width=3/ -] -qed. - -lemma TC_transitive2: ∀A,R1,R2. - transitive2 A R1 R2 → transitive2 A (TC … R1) (TC … R2). -#A #R1 #R2 #HR12 #a1 #a0 #H elim H -a0 -[ #a0 #Ha10 #a2 #Ha02 - elim (TC_strap2 … HR12 … Ha02 … Ha10) -HR12 -a0 /3 width=3/ -| #a #a0 #_ #Ha0 #IHa #a2 #Ha02 - elim (TC_strap2 … HR12 … Ha02 … Ha0) -HR12 -a0 #a0 #Ha0 #Ha02 - elim (IHa … Ha0) -a /4 width=3/ -] -qed. - -definition NF: ∀A. relation A → relation A → predicate A ≝ - λA,R,S,a1. ∀a2. R a1 a2 → S a1 a2. - -inductive SN (A) (R,S:relation A): predicate A ≝ -| SN_intro: ∀a1. (∀a2. R a1 a2 → (S a1 a2 → False) → SN A R S a2) → SN A R S a1 -. - -lemma NF_to_SN: ∀A,R,S,a. NF A R S a → SN A R S a. -#A #R #S #a1 #Ha1 -@SN_intro #a2 #HRa12 #HSa12 -elim (HSa12 ?) -HSa12 /2 width=1/ -qed.