X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fsyntax%2Fappend_length.ma;fp=matita%2Fmatita%2Fcontribs%2Flambdadelta%2Fbasic_2%2Fsyntax%2Fappend_length.ma;h=0000000000000000000000000000000000000000;hb=ff612dc35167ec0c145864c9aa8ae5e1ebe20a48;hp=e7c79ebeeb2627e513618ca3dab1c9c992a2bd3e;hpb=222044da28742b24584549ba86b1805a87def070;p=helm.git diff --git a/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma b/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.ma deleted file mode 100644 index e7c79ebee..000000000 --- a/matita/matita/contribs/lambdadelta/basic_2/syntax/append_length.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 "basic_2/syntax/lenv_length.ma". -include "basic_2/syntax/append.ma". - -(* APPEND FOR LOCAL ENVIRONMENTS ********************************************) - -(* Properties with length for local environments ****************************) - -lemma append_length: ∀L1,L2. |L1 + L2| = |L1| + |L2|. -#L1 #L2 elim L2 -L2 // -#L2 #I >append_bind >length_bind >length_bind // -qed. - -lemma ltail_length: ∀I,L. |ⓘ{I}.L| = ↑|L|. -#I #L >append_length // -qed. - -(* Advanced inversion lemmas on length for local environments ***************) - -(* Basic_2A1: was: length_inv_pos_dx_ltail *) -lemma length_inv_succ_dx_ltail: ∀L,n. |L| = ↑n → - ∃∃I,K. |K| = n & L = ⓘ{I}.K. -#Y #n #H elim (length_inv_succ_dx … H) -H #I #L #Hn #HLK destruct -elim (lenv_case_tail … L) [2: * #K #J ] -#H destruct /2 width=4 by ex2_2_intro/ -qed-. - -(* Basic_2A1: was: length_inv_pos_sn_ltail *) -lemma length_inv_succ_sn_ltail: ∀L,n. ↑n = |L| → - ∃∃I,K. n = |K| & L = ⓘ{I}.K. -#Y #n #H elim (length_inv_succ_sn … H) -H #I #L #Hn #HLK destruct -elim (lenv_case_tail … L) [2: * #K #J ] -#H destruct /2 width=4 by ex2_2_intro/ -qed-. - -(* Inversion lemmas with length for local environments **********************) - -(* Basic_2A1: was: append_inj_sn *) -lemma append_inj_length_sn: ∀K1,K2,L1,L2. L1 + K1 = L2 + K2 → |K1| = |K2| → - L1 = L2 ∧ K1 = K2. -#K1 elim K1 -K1 -[ * /2 width=1 by conj/ - #K2 #I2 #L1 #L2 #_ >length_atom >length_bind - #H destruct -| #K1 #I1 #IH * - [ #L1 #L2 #_ >length_atom >length_bind - #H destruct - | #K2 #I2 #L1 #L2 #H1 >length_bind >length_bind #H2 - elim (destruct_lbind_lbind_aux … H1) -H1 #H1 #H3 destruct (**) (* destruct lemma needed *) - elim (IH … H1) -IH -H1 /3 width=4 by conj/ - ] -] -qed-. - -(* Note: lemma 750 *) -(* Basic_2A1: was: append_inj_dx *) -lemma append_inj_length_dx: ∀K1,K2,L1,L2. L1 + K1 = L2 + K2 → |L1| = |L2| → - L1 = L2 ∧ K1 = K2. -#K1 elim K1 -K1 -[ * /2 width=1 by conj/ - #K2 #I2 #L1 #L2 >append_atom >append_bind #H destruct - >length_bind >append_length >plus_n_Sm - #H elim (plus_xSy_x_false … H) -| #K1 #I1 #IH * - [ #L1 #L2 >append_bind >append_atom #H destruct - >length_bind >append_length >plus_n_Sm #H - lapply (discr_plus_x_xy … H) -H #H destruct - | #K2 #I2 #L1 #L2 >append_bind >append_bind #H1 #H2 - elim (destruct_lbind_lbind_aux … H1) -H1 #H1 #H3 destruct (**) (* destruct lemma needed *) - elim (IH … H1) -IH -H1 /2 width=1 by conj/ - ] -] -qed-. - -(* Advanced inversion lemmas ************************************************) - -lemma append_inj_dx: ∀L,K1,K2. L+K1 = L+K2 → K1 = K2. -#L #K1 #K2 #H elim (append_inj_length_dx … H) -H // -qed-. - -lemma append_inv_refl_dx: ∀L,K. L+K = L → K = ⋆. -#L #K #H elim (append_inj_dx … (⋆) … H) // -qed-. - -lemma append_inv_pair_dx: ∀I,L,K,V. L+K = L.ⓑ{I}V → K = ⋆.ⓑ{I}V. -#I #L #K #V #H elim (append_inj_dx … (⋆.ⓑ{I}V) … H) // -qed-. - -(* Basic eliminators ********************************************************) - -(* Basic_1: was: c_tail_ind *) -(* Basic_2A1: was: lenv_ind_alt *) -lemma lenv_ind_tail: ∀Q:predicate lenv. - Q (⋆) → (∀I,L. Q L → Q (ⓘ{I}.L)) → ∀L. Q L. -#Q #IH1 #IH2 #L @(f_ind … length … L) -L #x #IHx * // -#L #I -IH1 #H destruct -elim (lenv_case_tail … L) [2: * #K #J ] -#H destruct /3 width=1 by/ -qed-.