src/HOL/AxClasses/Semigroups.thy

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/AxClasses/Semigroups.thy	Tue Oct 03 18:30:56 2000 +0200
@@ -0,0 +1,21 @@
+(*  Title:      HOL/AxClasses/Semigroups.thy
+    ID:         $Id$
+    Author:     Markus Wenzel, TU Muenchen
+*)
+
+theory Semigroups = Main:
+
+consts
+  times :: "'a => 'a => 'a"    (infixl "[*]" 70)
+
+axclass semigroup < "term"
+  assoc: "(x [*] y) [*] z = x [*] (y [*] z)"
+
+
+consts
+  plus :: "'a => 'a => 'a"    (infixl "[+]" 70)
+
+axclass plus_semigroup < "term"
+  assoc: "(x [+] y) [+] z = x [+] (y [+] z)"
+
+end