refactoring ...

[helm.git] / matita / matita / contribs / lambda_delta / Basic_2 / grammar / term.ma

diff --git a/matita/matita/contribs/lambda_delta/Basic_2/grammar/term.ma b/matita/matita/contribs/lambda_delta/Basic_2/grammar/term.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                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+include "Basic-2/grammar/item.ma".
+
+(* TERMS ********************************************************************)
+
+(* terms *)
+inductive term: Type[0] ≝
+  | TAtom: item0 → term               (* atomic item construction *)
+  | TPair: item2 → term → term → term (* binary item construction *)
+.
+
+interpretation "sort (term)" 'Star k = (TAtom (Sort k)).
+
+interpretation "local reference (term)" 'LRef i = (TAtom (LRef i)).
+
+interpretation "term construction (atomic)" 'SItem I = (TAtom I).
+
+interpretation "term construction (binary)" 'SItem I T1 T2 = (TPair I T1 T2).
+
+interpretation "term binding construction (binary)" 'SBind I T1 T2 = (TPair (Bind I) T1 T2).
+
+interpretation "term flat construction (binary)" 'SFlat I T1 T2 = (TPair (Flat I) T1 T2).