helm/software/matita/contribs/LAMBDA-TYPES/Unified/SUB/Switch/defs.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
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   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 set "baseuri" "cic:/matita/LAMBDA-TYPES/Unified/SUB/Switch/defs".
  16
  17 (* POLARITY SWITCH RELATION
  18 *)
  19
  20 include "SUB/Term/defs.ma".
  21
  22 inductive Switch (q1:Bool): Head \to Bool \to Prop \def
  23    | switch_bind: \forall q2,p. (p -- q1 == q2) \to
  24                   \forall r. Switch q1 (bind p r) q2
  25    | switch_flat: \forall q2,p. (p -- q1 == q2) \to
  26                   \forall r. Switch q1 (flat p r) q2
  27 .