helm/matita/contribs/PREDICATIVE-TOPOLOGY/subsets_defs.ma

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   3 (*      ||M||                                                             *)
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  11 (*        v         GNU General Public License Version 2                  *)
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  13 (**************************************************************************)
  14
  15 set "baseuri" "cic:/matita/PREDICATIVE-TOPOLOGY/subsets_defs".
  16
  17 include "qd_defs.ma".
  18
  19 (* SUBSETS
  20    - We use predicative subsets coded as propositional functions
  21      according to G.Sambin and S.Valentini "Toolbox"
  22 *)
  23
  24 definition Subset \def \forall (D:QD). D \to Prop.
  25
  26 alias id "True" = "cic:/Coq/Init/Logic/True.ind#xpointer(1/1)".
  27 definition stop \def \lambda (D:QD). \lambda (a:(ac (qd D))). True.