src/ZF/inductive.ML
changeset 0 a5a9c433f639
child 516 1957113f0d7d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ZF/inductive.ML	Thu Sep 16 12:20:38 1993 +0200
@@ -0,0 +1,63 @@
+(*  Title: 	ZF/inductive.ML
+    ID:         $Id$
+    Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
+    Copyright   1993  University of Cambridge
+
+Inductive Definitions for Zermelo-Fraenkel Set Theory
+
+Uses least fixedpoints with standard products and sums
+
+Sums are used only for mutual recursion;
+Products are used only to derive "streamlined" induction rules for relations
+*)
+
+
+structure Lfp =
+  struct
+  val oper	= Const("lfp",      [iT,iT-->iT]--->iT)
+  val bnd_mono	= Const("bnd_mono", [iT,iT-->iT]--->oT)
+  val bnd_monoI	= bnd_monoI
+  val subs	= def_lfp_subset
+  val Tarski	= def_lfp_Tarski
+  val induct	= def_induct
+  end;
+
+structure Standard_Prod =
+  struct
+  val sigma	= Const("Sigma", [iT, iT-->iT]--->iT)
+  val pair	= Const("Pair", [iT,iT]--->iT)
+  val split_const	= Const("split", [[iT,iT]--->iT, iT]--->iT)
+  val fsplit_const	= Const("fsplit", [[iT,iT]--->oT, iT]--->oT)
+  val pair_iff	= Pair_iff
+  val split_eq	= split
+  val fsplitI	= fsplitI
+  val fsplitD	= fsplitD
+  val fsplitE	= fsplitE
+  end;
+
+structure Standard_Sum =
+  struct
+  val sum	= Const("op +", [iT,iT]--->iT)
+  val inl	= Const("Inl", iT-->iT)
+  val inr	= Const("Inr", iT-->iT)
+  val elim	= Const("case", [iT-->iT, iT-->iT, iT]--->iT)
+  val case_inl	= case_Inl
+  val case_inr	= case_Inr
+  val inl_iff	= Inl_iff
+  val inr_iff	= Inr_iff
+  val distinct	= Inl_Inr_iff
+  val distinct' = Inr_Inl_iff
+  end;
+
+functor Inductive_Fun (Ind: INDUCTIVE) : sig include INTR_ELIM INDRULE end =
+struct
+structure Intr_elim = 
+    Intr_elim_Fun(structure Ind=Ind and Fp=Lfp and 
+		  Pr=Standard_Prod and Su=Standard_Sum);
+
+structure Indrule = Indrule_Fun (structure Ind=Ind and 
+		                 Pr=Standard_Prod and Intr_elim=Intr_elim);
+
+open Intr_elim Indrule
+end;
+