src/HOL/Algebra/abstract/RingHomo.thy
changeset 17479 68a7acb5f22e
parent 13735 7de9342aca7a
child 20318 0e0ea63fe768
--- a/src/HOL/Algebra/abstract/RingHomo.thy	Sat Sep 17 20:16:35 2005 +0200
+++ b/src/HOL/Algebra/abstract/RingHomo.thy	Sat Sep 17 20:49:14 2005 +0200
@@ -4,14 +4,12 @@
     Author: Clemens Ballarin, started 15 April 1997
 *)
 
-RingHomo = Ring +
-
-consts
-  homo	:: ('a::ring => 'b::ring) => bool
+theory RingHomo imports Ring begin
 
-defs
-  homo_def	"homo f == (ALL a b. f (a + b) = f a + f b &
-			      f (a * b) = f a * f b) &
-			   f 1 = 1"
+constdefs
+  homo  :: "('a::ring => 'b::ring) => bool"
+  "homo f == (ALL a b. f (a + b) = f a + f b &
+                                   f (a * b) = f a * f b) &
+                                   f 1 = 1"
 
 end