src/Pure/Tools/codegen_thingol.ML

       ]
   | pretty_def (Datatype ((vs, cs), insts)) =
       Pretty.block [
         Pretty.list "(" ")" (map (pretty_itype o IVarT) vs),
         Pretty.str " |=> ",
-        Pretty.gen_list " |" "" ""
+        Pretty.enum " |" "" ""
           (map (fn (c, tys) => (Pretty.block o Pretty.breaks)
             (Pretty.str c :: map pretty_itype tys)) cs),
         Pretty.str ", instances ",
         Pretty.enum "," "[" "]" (map Pretty.str insts)
       ]

   | pretty_def (Class ((supcls, (v, mems)), insts)) =
       Pretty.block [
         Pretty.str ("class var " ^ v ^ "extending "),
         Pretty.enum "," "[" "]" (map Pretty.str supcls),
         Pretty.str " with ",
-        Pretty.gen_list "," "[" "]"
+        Pretty.enum "," "[" "]"
           (map (fn (m, (_, ty)) => Pretty.block
             [Pretty.str (m ^ "::"), pretty_itype ty]) mems),
         Pretty.str " instances ",
         Pretty.enum "," "[" "]" (map Pretty.str insts)
       ]

         Pretty.str "class instance (",
         Pretty.str clsname,
         Pretty.str ", (",
         Pretty.str tyco,
         Pretty.str ", ",
-        Pretty.gen_list "," "[" "]" (map (Pretty.gen_list "," "{" "}" o
+        Pretty.enum "," "[" "]" (map (Pretty.enum "," "{" "}" o
           map Pretty.str o snd) arity),
         Pretty.str "))"
       ];
 
 fun pretty_module modl =