helm/software/matita/library/datatypes/compare.ma

   1 (**************************************************************************)
   2 (*       ___                                                                *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
   7 (*      ||T||       A.Asperti, C.Sacerdoti Coen,                          *)
   8 (*      ||A||       E.Tassi, S.Zacchiroli                                 *)
   9 (*      \   /                                                             *)
  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU Lesser General Public License Version 2.1         *)
  12 (*                                                                        *)
  13 (**************************************************************************)
  14
  15 inductive compare :Set \def
  16 | LT : compare
  17 | EQ : compare
  18 | GT : compare.
  19
  20 definition compare_invert: compare \to compare \def
  21   \lambda c.
  22     match c with
  23       [ LT \Rightarrow GT
  24       | EQ \Rightarrow EQ
  25       | GT \Rightarrow LT ].