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[helm.git] / matitaB / matita / contribs / ng_assembly / compiler / environment.ma

diff --git a/matitaB/matita/contribs/ng_assembly/compiler/environment.ma b/matitaB/matita/contribs/ng_assembly/compiler/environment.ma
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+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||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                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+(* ********************************************************************** *)
+(*                          Progetto FreeScale                            *)
+(*                                                                        *)
+(*   Sviluppato da: Ing. Cosimo Oliboni, oliboni@cs.unibo.it              *)
+(*   Sviluppo: 2008-2010                                                  *)
+(*                                                                        *)
+(* ********************************************************************** *)
+
+include "common/string.ma".
+include "compiler/ast_type.ma".
+
+(* ***************** *)
+(* GESTIONE AMBIENTE *)
+(* ***************** *)
+
+(* elemento: name + const + type *)
+nrecord envDsc : Type ≝
+ {
+ nameDsc: aux_str_type;
+ constDsc: bool;
+ typeDsc: ast_type
+ }.
+
+(* ambiente globale: (ambiente base + ambienti annidati) *)
+ninductive env_list : nat → Type ≝
+  env_nil: list envDsc → env_list O
+| env_cons: ∀n.list envDsc → env_list n → env_list (S n).
+
+ndefinition defined_envList ≝
+λd.λl:env_list d.match l with [ env_nil _ ⇒ False | env_cons _ _ _ ⇒ True ].
+
+(* bisogna bypassare la carenza di inversion *)
+nlemma defined_envList_S : ∀d.∀l:env_list (S d).defined_envList (S d) l.
+ #d; #l;
+ ngeneralize in match (refl_eq ? (S d));
+ ncases l in ⊢ (? ? % ? → %);
+ ##[ ##1: #dsc; #H; ndestruct (*nelim (nat_destruct_0_S … H)*)
+ ##| ##2: #n; #dsc; #sub; #H;
+          nnormalize;
+          napply I
+ ##]
+nqed.
+
+ndefinition cut_first_envList_aux : Πd.env_list (S d) → env_list d ≝
+λd.λl:env_list (S d).
+  match l
+   return λX.λY:env_list X.defined_envList X Y → env_list (pred X)
+  with
+   [ env_nil h ⇒ λp:defined_envList O (env_nil h).False_rect_Type0 ? p
+   | env_cons n h t ⇒ λp:defined_envList (S n) (env_cons n h t).t
+   ] (defined_envList_S d l).