matita/matita/contribs/lambdadelta/ground_2/lib/streams.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                  *)
  12 (*                                                                        *)
  13 (**************************************************************************)
  14
  15 include "ground_2/notation/functions/oplusright_3.ma".
  16 include "ground_2/lib/relations.ma".
  17
  18 (* STREAMS ******************************************************************)
  19
  20 coinductive stream (A:Type[0]): Type[0] ≝
  21 | seq: A → stream A → stream A
  22 .
  23
  24 interpretation "cons (nstream)" 'OPlusRight A a u = (seq A a u).
  25
  26 (* Basic properties *********************************************************)
  27
  28 lemma stream_rew (A) (t:stream A): match t with [ seq a u ⇒ a ⨮ u ] = t.
  29 #A * //
  30 qed.