| author | haftmann |
| Tue, 19 Sep 2006 15:22:35 +0200 | |
| changeset 20604 | 9dba9c7872c9 |
| parent 16417 | 9bc16273c2d4 |
| permissions | -rw-r--r-- |
(* Title: HOL/AxClasses/Semigroups.thy ID: $Id$ Author: Markus Wenzel, TU Muenchen *) theory Semigroups imports Main begin consts times :: "'a => 'a => 'a" (infixl "[*]" 70) axclass semigroup < type assoc: "(x [*] y) [*] z = x [*] (y [*] z)" consts plus :: "'a => 'a => 'a" (infixl "[+]" 70) axclass plus_semigroup < type assoc: "(x [+] y) [+] z = x [+] (y [+] z)" end