Subst/AList.thy

   alist_rec  :: "[('a*'b)list, 'c, ['a, 'b, ('a*'b)list, 'c]=>'c] => 'c"
   assoc      :: "['a,'b,('a*'b) list] => 'b"
 
 rules
 
-  alist_rec_def "alist_rec(al,b,c) == list_rec(al, b, split(c))"
+  alist_rec_def "alist_rec(al,b,c) == list_rec(b, split(c), al)"
 
   assoc_def     "assoc(v,d,al) == alist_rec(al,d,%x y xs g.if(v=x,y,g))"
 
 end