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- lambda_delta: programmed renaming to lambdadelta
[helm.git] / matita / matita / contribs / lambda_delta / basic_2 / grammar / lenv_length.ma
diff --git a/matita/matita/contribs/lambda_delta/basic_2/grammar/lenv_length.ma b/matita/matita/contribs/lambda_delta/basic_2/grammar/lenv_length.ma
deleted file mode 100644 (file)
index faf6de0..0000000
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@@ -1,52 +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/grammar/lenv.ma".
-
-(* LENGTH OF A LOCAL ENVIRONMENT ********************************************)
-
-let rec length L ≝ match L with
-[ LAtom       ⇒ 0
-| LPair L _ _ ⇒ length L + 1
-].
-
-interpretation "length (local environment)" 'card L = (length L).
-
-(* Basic inversion lemmas ***************************************************)
-
-lemma length_inv_zero_dx: ∀L. |L| = 0 → L = ⋆.
-* // #L #I #V normalize <plus_n_Sm #H destruct
-qed-.
-
-lemma length_inv_zero_sn: ∀L. 0 = |L| → L = ⋆.
-* // #L #I #V normalize <plus_n_Sm #H destruct
-qed-.
-
-lemma length_inv_pos_dx: ∀d,L. |L| = d + 1 →
-                         ∃∃I,K,V. |K| = d & L = K. ⓑ{I}V.
-#d *
-[ normalize <plus_n_Sm #H destruct
-| #K #I #V #H
-  lapply (injective_plus_l … H) -H /2 width=5/
-]
-qed-.
-
-lemma length_inv_pos_sn: ∀d,L. d + 1 = |L| →
-                         ∃∃I,K,V. d = |K| & L = K. ⓑ{I}V.
-#d *
-[ normalize <plus_n_Sm #H destruct
-| #K #I #V #H
-  lapply (injective_plus_l … H) -H /2 width=5/
-]
-qed-.