matita/matita/contribs/lambda_delta/basic_2/grammar/lenv_weight.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
   7 (*      ||T||         The HELM team.                                      *)
   8 (*      ||A||         http://helm.cs.unibo.it                             *)
   9 (*      \   /                                                             *)
  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
  12 (*                                                                        *)
  13 (**************************************************************************)
  14
  15 include "basic_2/grammar/term_weight.ma".
  16 include "basic_2/grammar/lenv.ma".
  17
  18 (* WEIGHT OF A LOCAL ENVIRONMENT ********************************************)
  19
  20 let rec lw L ≝ match L with
  21 [ LAtom       ⇒ 0
  22 | LPair L _ V ⇒ lw L + #[V]
  23 ].
  24
  25 interpretation "weight (local environment)" 'Weight L = (lw L).
  26
  27 (* Basic_1: removed theorems 2: clt_cong clt_head clt_thead *)
  28 (* Basic_1: note: clt_thead should be renamed clt_ctail *)