diff -r 000000000000 -r a5a9c433f639 src/ZF/ex/Prop.ML
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ZF/ex/Prop.ML	Thu Sep 16 12:20:38 1993 +0200
@@ -0,0 +1,47 @@
+(*  Title: 	ZF/ex/prop.ML
+    ID:         $Id$
+    Author: 	Lawrence C Paulson
+    Copyright   1993  University of Cambridge
+
+Datatype definition of propositional logic formulae and inductive definition
+of the propositional tautologies.
+*)
+
+(*Example of a datatype with mixfix syntax for some constructors*)
+structure Prop = Datatype_Fun
+ (val thy = Univ.thy;
+  val rec_specs = 
+      [("prop", "univ(0)",
+	  [(["Fls"],	"i"),
+	   (["Var"],	"i=>i"),
+	   (["op =>"],	"[i,i]=>i")])];
+  val rec_styp = "i";
+  val ext = Some (NewSext {
+	     mixfix =
+	      [Mixfix("#_", "i => i", "Var", [100], 100),
+	       Infixr("=>", "[i,i] => i", 90)],
+	     xrules = [],
+	     parse_ast_translation = [],
+	     parse_preproc = None,
+	     parse_postproc = None,
+	     parse_translation = [],
+	     print_translation = [],
+	     print_preproc = None,
+	     print_postproc = None,
+	     print_ast_translation = []});
+  val sintrs = 
+	  ["Fls : prop",
+	   "n: nat ==> #n : prop",
+	   "[| p: prop;  q: prop |] ==> p=>q : prop"];
+  val monos = [];
+  val type_intrs = data_typechecks;
+  val type_elims = []);
+
+val [FlsI,VarI,ImpI] = Prop.intrs;
+
+
+(** Type-checking rules **)
+
+val ImpE = Prop.mk_cases Prop.con_defs "p=>q : prop";
+
+writeln"Reached end of file.";