X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fetc_new%2Fdrops%2Fdrops.etc;h=5d51b83c850108ebc030f3156e81d2af1824aca6;hb=ad3ca38634cfae29e8c26d0ab23cb466407eca5e;hp=86ca4c76a43d973aa3ee394c156ed61f4a2f7a26;hpb=93bba1c94779e83184d111cd077d4167e42a74aa;p=helm.git diff --git a/matita/matita/contribs/lambdadelta/basic_2/etc_new/drops/drops.etc b/matita/matita/contribs/lambdadelta/basic_2/etc_new/drops/drops.etc index 86ca4c76a..5d51b83c8 100644 --- a/matita/matita/contribs/lambdadelta/basic_2/etc_new/drops/drops.etc +++ b/matita/matita/contribs/lambdadelta/basic_2/etc_new/drops/drops.etc @@ -1,53 +1,2 @@ -lemma drop_split: ∀L1,L2,l,m2,s. ⬇[s, l, m2] L1 ≡ L2 → ∀m1. m1 ≤ m2 → - ∃∃L. ⬇[s, l, m2 - m1] L1 ≡ L & ⬇[s, l, m1] L ≡ L2. -#L1 #L2 #l #m2 #s #H elim H -L1 -L2 -l -m2 -[ #l #m2 #Hs #m1 #Hm12 @(ex2_intro … (⋆)) - @drop_atom #H lapply (Hs H) -s #H destruct /2 width=1 by le_n_O_to_eq/ -| #I #L1 #V #m1 #Hm1 lapply (le_n_O_to_eq … Hm1) -Hm1 - #H destruct /2 width=3 by ex2_intro/ -| #I #L1 #L2 #V #m2 #HL12 #IHL12 #m1 @(nat_ind_plus … m1) -m1 - [ /3 width=3 by drop_drop, ex2_intro/ - | -HL12 #m1 #_ #Hm12 lapply (le_plus_to_le_r … Hm12) -Hm12 - #Hm12 elim (IHL12 … Hm12) -IHL12 >minus_plus_plus_l - #L #HL1 #HL2 elim (lt_or_ge (|L1|) (m2-m1)) #H0 - [ elim (drop_inv_O1_gt … HL1 H0) -HL1 #H1 #H2 destruct - elim (drop_inv_atom1 … HL2) -HL2 #H #_ destruct - @(ex2_intro … (⋆)) [ @drop_O1_ge normalize // ] - @drop_atom #H destruct - | elim (drop_O1_pair … HL1 H0 I V) -HL1 -H0 /3 width=5 by drop_drop, ex2_intro/ - ] - ] -| #I #L1 #L2 #V1 #V2 #l #m2 #_ #HV21 #IHL12 #m1 #Hm12 elim (IHL12 … Hm12) -IHL12 - #L #HL1 #HL2 elim (lift_split … HV21 l m1) -HV21 /3 width=5 by drop_skip, ex2_intro/ -] -qed-. - lemma drop_inv_refl: ∀L,l,m. ⬇[Ⓕ, l, m] L ≡ L → m = 0. /2 width=5 by drop_inv_length_eq/ qed-. - -fact drop_inv_FT_aux: ∀L1,L2,s,l,m. ⬇[s, l, m] L1 ≡ L2 → - ∀I,K,V. L2 = K.ⓑ{I}V → s = Ⓣ → l = 0 → - ⬇[Ⓕ, l, m] L1 ≡ K.ⓑ{I}V. -#L1 #L2 #s #l #m #H elim H -L1 -L2 -l -m -[ #l #m #_ #J #K #W #H destruct -| #I #L #V #J #K #W #H destruct // -| #I #L1 #L2 #V #m #_ #IHL12 #J #K #W #H1 #H2 destruct - /3 width=1 by drop_drop/ -| #I #L1 #L2 #V1 #V2 #l #m #_ #_ #_ #J #K #W #_ #_ #H - elim (ysucc_inv_O_dx … H) -] -qed-. - -lemma drop_inv_FT: ∀I,L,K,V,m. ⬇[Ⓣ, 0, m] L ≡ K.ⓑ{I}V → ⬇[m] L ≡ -K.ⓑ{I}V. -/2 width=5 by drop_inv_FT_aux/ qed. - -lemma drop_inv_gen: ∀I,L,K,V,s,m. ⬇[s, 0, m] L ≡ K.ⓑ{I}V → ⬇[m] L ≡ -K.ⓑ{I}V. -#I #L #K #V * /2 width=1 by drop_inv_FT/ -qed-. - -lemma drop_inv_T: ∀I,L,K,V,s,m. ⬇[Ⓣ, 0, m] L ≡ K.ⓑ{I}V → ⬇[s, 0, m] L -≡ K.ⓑ{I}V. -#I #L #K #V * /2 width=1 by drop_inv_FT/ -qed-.