X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fstatic%2Frex_drops.ma;fp=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fstatic%2Frex_drops.ma;h=7ce890273a7b2c9de98f4f6a1ae00bce8bdb60ff;hb=222044da28742b24584549ba86b1805a87def070;hp=0000000000000000000000000000000000000000;hpb=5c186c72f508da0849058afeecc6877cd9ed6303;p=helm.git diff --git a/matita/matita/contribs/lambdadelta/basic_2/static/rex_drops.ma b/matita/matita/contribs/lambdadelta/basic_2/static/rex_drops.ma new file mode 100644 index 000000000..7ce890273 --- /dev/null +++ b/matita/matita/contribs/lambdadelta/basic_2/static/rex_drops.ma @@ -0,0 +1,124 @@ +(**************************************************************************) +(* ___ *) +(* ||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 "basic_2/relocation/drops_cext2.ma". +include "basic_2/relocation/drops_sex.ma". +include "basic_2/static/frees_drops.ma". +include "basic_2/static/rex.ma". + +(* GENERIC EXTENSION ON REFERRED ENTRIES OF A CONTEXT-SENSITIVE REALTION ****) + +definition f_dedropable_sn: predicate (relation3 lenv term term) ≝ + λR. ∀b,f,L1,K1. ⬇*[b, f] L1 ≘ K1 → + ∀K2,T. K1 ⪤[R, T] K2 → ∀U. ⬆*[f] T ≘ U → + ∃∃L2. L1 ⪤[R, U] L2 & ⬇*[b, f] L2 ≘ K2 & L1 ≡[f] L2. + +definition f_dropable_sn: predicate (relation3 lenv term term) ≝ + λR. ∀b,f,L1,K1. ⬇*[b, f] L1 ≘ K1 → 𝐔⦃f⦄ → + ∀L2,U. L1 ⪤[R, U] L2 → ∀T. ⬆*[f] T ≘ U → + ∃∃K2. K1 ⪤[R, T] K2 & ⬇*[b, f] L2 ≘ K2. + +definition f_dropable_dx: predicate (relation3 lenv term term) ≝ + λR. ∀L1,L2,U. L1 ⪤[R, U] L2 → + ∀b,f,K2. ⬇*[b, f] L2 ≘ K2 → 𝐔⦃f⦄ → ∀T. ⬆*[f] T ≘ U → + ∃∃K1. ⬇*[b, f] L1 ≘ K1 & K1 ⪤[R, T] K2. + +definition f_transitive_next: relation3 … ≝ λR1,R2,R3. + ∀f,L,T. L ⊢ 𝐅*⦃T⦄ ≘ f → + ∀g,I,K,n. ⬇*[n] L ≘ K.ⓘ{I} → ↑g = ⫱*[n] f → + sex_transitive (cext2 R1) (cext2 R2) (cext2 R3) (cext2 R1) cfull g K I. + +(* Properties with generic slicing for local environments *******************) + +lemma rex_liftable_dedropable_sn: ∀R. (∀L. reflexive ? (R L)) → + d_liftable2_sn … lifts R → f_dedropable_sn R. +#R #H1R #H2R #b #f #L1 #K1 #HLK1 #K2 #T * #f1 #Hf1 #HK12 #U #HTU +elim (frees_total L1 U) #f2 #Hf2 +lapply (frees_fwd_coafter … Hf2 … HLK1 … HTU … Hf1) -HTU #Hf +elim (sex_liftable_co_dedropable_sn … HLK1 … HK12 … Hf) -f1 -K1 +/3 width=6 by cext2_d_liftable2_sn, cfull_lift_sn, ext2_refl, ex3_intro, ex2_intro/ +qed-. + +lemma rex_trans_next: ∀R1,R2,R3. rex_transitive R1 R2 R3 → f_transitive_next R1 R2 R3. +#R1 #R2 #R3 #HR #f #L1 #T #Hf #g #I1 #K1 #n #HLK #Hgf #I #H +generalize in match HLK; -HLK elim H -I1 -I +[ #I #_ #L2 #_ #I2 #H + lapply (ext2_inv_unit_sn … H) -H #H destruct + /2 width=1 by ext2_unit/ +| #I #V1 #V #HV1 #HLK1 #L2 #HL12 #I2 #H + elim (ext2_inv_pair_sn … H) -H #V2 #HV2 #H destruct + elim (frees_inv_drops_next … Hf … HLK1 … Hgf) -f -HLK1 #f #Hf #Hfg + /5 width=5 by ext2_pair, sle_sex_trans, ex2_intro/ +] +qed. + +(* Inversion lemmas with generic slicing for local environments *************) + +(* Basic_2A1: uses: llpx_sn_inv_lift_le llpx_sn_inv_lift_be llpx_sn_inv_lift_ge *) +(* Basic_2A1: was: llpx_sn_drop_conf_O *) +lemma rex_dropable_sn: ∀R. f_dropable_sn R. +#R #b #f #L1 #K1 #HLK1 #H1f #L2 #U * #f2 #Hf2 #HL12 #T #HTU +elim (frees_total K1 T) #f1 #Hf1 +lapply (frees_fwd_coafter … Hf2 … HLK1 … HTU … Hf1) -HTU #H2f +elim (sex_co_dropable_sn … HLK1 … HL12 … H2f) -f2 -L1 +/3 width=3 by ex2_intro/ +qed-. + +(* Basic_2A1: was: llpx_sn_drop_trans_O *) +(* Note: the proof might be simplified *) +lemma rex_dropable_dx: ∀R. f_dropable_dx R. +#R #L1 #L2 #U * #f2 #Hf2 #HL12 #b #f #K2 #HLK2 #H1f #T #HTU +elim (drops_isuni_ex … H1f L1) #K1 #HLK1 +elim (frees_total K1 T) #f1 #Hf1 +lapply (frees_fwd_coafter … Hf2 … HLK1 … HTU … Hf1) -K1 #H2f +elim (sex_co_dropable_dx … HL12 … HLK2 … H2f) -L2 +/4 width=9 by frees_inv_lifts, ex2_intro/ +qed-. + +(* Basic_2A1: uses: llpx_sn_inv_lift_O *) +lemma rex_inv_lifts_bi: ∀R,L1,L2,U. L1 ⪤[R, U] L2 → ∀b,f. 𝐔⦃f⦄ → + ∀K1,K2. ⬇*[b, f] L1 ≘ K1 → ⬇*[b, f] L2 ≘ K2 → + ∀T. ⬆*[f] T ≘ U → K1 ⪤[R, T] K2. +#R #L1 #L2 #U #HL12 #b #f #Hf #K1 #K2 #HLK1 #HLK2 #T #HTU +elim (rex_dropable_sn … HLK1 … HL12 … HTU) -L1 -U // #Y #HK12 #HY +lapply (drops_mono … HY … HLK2) -b -f -L2 #H destruct // +qed-. + +lemma rex_inv_lref_pair_sn: ∀R,L1,L2,i. L1 ⪤[R, #i] L2 → ∀I,K1,V1. ⬇*[i] L1 ≘ K1.ⓑ{I}V1 → + ∃∃K2,V2. ⬇*[i] L2 ≘ K2.ⓑ{I}V2 & K1 ⪤[R, V1] K2 & R K1 V1 V2. +#R #L1 #L2 #i #HL12 #I #K1 #V1 #HLK1 elim (rex_dropable_sn … HLK1 … HL12 (#0)) -HLK1 -HL12 // +#Y #HY #HLK2 elim (rex_inv_zero_pair_sn … HY) -HY +#K2 #V2 #HK12 #HV12 #H destruct /2 width=5 by ex3_2_intro/ +qed-. + +lemma rex_inv_lref_pair_dx: ∀R,L1,L2,i. L1 ⪤[R, #i] L2 → ∀I,K2,V2. ⬇*[i] L2 ≘ K2.ⓑ{I}V2 → + ∃∃K1,V1. ⬇*[i] L1 ≘ K1.ⓑ{I}V1 & K1 ⪤[R, V1] K2 & R K1 V1 V2. +#R #L1 #L2 #i #HL12 #I #K2 #V2 #HLK2 elim (rex_dropable_dx … HL12 … HLK2 … (#0)) -HLK2 -HL12 // +#Y #HLK1 #HY elim (rex_inv_zero_pair_dx … HY) -HY +#K1 #V1 #HK12 #HV12 #H destruct /2 width=5 by ex3_2_intro/ +qed-. + +lemma rex_inv_lref_unit_sn: ∀R,L1,L2,i. L1 ⪤[R, #i] L2 → ∀I,K1. ⬇*[i] L1 ≘ K1.ⓤ{I} → + ∃∃f,K2. ⬇*[i] L2 ≘ K2.ⓤ{I} & K1 ⪤[cext2 R, cfull, f] K2 & 𝐈⦃f⦄. +#R #L1 #L2 #i #HL12 #I #K1 #HLK1 elim (rex_dropable_sn … HLK1 … HL12 (#0)) -HLK1 -HL12 // +#Y #HY #HLK2 elim (rex_inv_zero_unit_sn … HY) -HY +#f #K2 #Hf #HK12 #H destruct /2 width=5 by ex3_2_intro/ +qed-. + +lemma rex_inv_lref_unit_dx: ∀R,L1,L2,i. L1 ⪤[R, #i] L2 → ∀I,K2. ⬇*[i] L2 ≘ K2.ⓤ{I} → + ∃∃f,K1. ⬇*[i] L1 ≘ K1.ⓤ{I} & K1 ⪤[cext2 R, cfull, f] K2 & 𝐈⦃f⦄. +#R #L1 #L2 #i #HL12 #I #K2 #HLK2 elim (rex_dropable_dx … HL12 … HLK2 … (#0)) -HLK2 -HL12 // +#Y #HLK1 #HY elim (rex_inv_zero_unit_dx … HY) -HY +#f #K2 #Hf #HK12 #H destruct /2 width=5 by ex3_2_intro/ +qed-.