matita/matita/contribs/lambdadelta/ground/relocation/pr_id.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
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  13 (**************************************************************************)
  14
  15 include "ground/notation/functions/element_i_0.ma".
  16 include "ground/relocation/pr_map.ma".
  17
  18 (* IDENTITY ELEMENT FOR PARTIAL RELOCATION MAPS *****************************)
  19
  20 (*** id *)
  21 corec definition pr_id: pr_map ≝ ⫯pr_id.
  22
  23 interpretation
  24   "identity element (partial relocation streams)"
  25   'ElementI = (pr_id).
  26
  27 (* Basic constructions (specific) *******************************************)
  28
  29 (*** id_rew *)
  30 lemma pr_id_unfold: ⫯𝐢 = 𝐢.
  31 <(stream_unfold … (𝐢)) in ⊢ (???%); //
  32 qed.