prefer vacuous definitional type classes over axiomatic ones;

--- a/src/HOL/TLA/Action.thy	Mon Feb 10 17:23:13 2014 +0100
+++ b/src/HOL/TLA/Action.thy	Mon Feb 10 21:00:56 2014 +0100
@@ -15,7 +15,7 @@
 type_synonym 'a trfun = "(state * state) => 'a"
 type_synonym action   = "bool trfun"
 
-arities prod :: (world, world) world
+instance prod :: (world, world) world ..
 
 consts
   (** abstract syntax **)

--- a/src/HOL/TLA/Init.thy	Mon Feb 10 17:23:13 2014 +0100
+++ b/src/HOL/TLA/Init.thy	Mon Feb 10 21:00:56 2014 +0100
@@ -12,7 +12,7 @@
 begin
 
 typedecl behavior
-arities behavior :: world
+instance behavior :: world ..
 
 type_synonym temporal = "behavior form"
 

--- a/src/HOL/TLA/Intensional.thy	Mon Feb 10 17:23:13 2014 +0100
+++ b/src/HOL/TLA/Intensional.thy	Mon Feb 10 21:00:56 2014 +0100
@@ -10,8 +10,7 @@
 imports Main
 begin
 
-classes world
-classrel world < type
+class world
 
 (** abstract syntax **)
 

--- a/src/HOL/TLA/Stfun.thy	Mon Feb 10 17:23:13 2014 +0100
+++ b/src/HOL/TLA/Stfun.thy	Mon Feb 10 21:00:56 2014 +0100
@@ -10,8 +10,7 @@
 begin
 
 typedecl state
-
-arities state :: world
+instance state :: world ..
 
 type_synonym 'a stfun = "state => 'a"
 type_synonym stpred  = "bool stfun"