List.thy

   hd            :: "'a list => 'a"
   tl,ttl        :: "'a list => 'a list"
   mem		:: "['a, 'a list] => bool"			(infixl 55)
   list_all      :: "('a => bool) => ('a list => bool)"
   map           :: "('a=>'b) => ('a list => 'b list)"
-  "@"		:: "['a list, 'a list] => 'a list"		(infixl 65)
+  "@"		:: "['a list, 'a list] => 'a list"		(infixr 65)
   list_case     :: "['a list, 'b, ['a, 'a list]=>'b] => 'b"
   filter	:: "['a => bool, 'a list] => 'a list"
 
   (* List Enumeration *)