diff -r 000000000000 -r a5a9c433f639 src/FOL/ex/prolog.thy
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/FOL/ex/prolog.thy	Thu Sep 16 12:20:38 1993 +0200
@@ -0,0 +1,22 @@
+(*  Title: 	FOL/ex/prolog.thy
+    ID:         $Id$
+    Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
+    Copyright   1992  University of Cambridge
+
+First-Order Logic: PROLOG examples
+
+Inherits from FOL the class term, the type o, and the coercion Trueprop
+*)
+
+Prolog = FOL +
+types   list 1
+arities list    :: (term)term
+consts  Nil     :: "'a list"
+        ":"     :: "['a, 'a list]=> 'a list"            (infixr 60)
+        app     :: "['a list, 'a list, 'a list] => o"
+        rev     :: "['a list, 'a list] => o"
+rules   appNil  "app(Nil,ys,ys)"
+        appCons "app(xs,ys,zs) ==> app(x:xs, ys, x:zs)"
+        revNil  "rev(Nil,Nil)"
+        revCons "[| rev(xs,ys);  app(ys, x:Nil, zs) |] ==> rev(x:xs, zs)"
+end