src/HOL/Tools/Nitpick/nitpick_rep.ML

     (case (best_one_rep_for_type scope T1, best_one_rep_for_type scope T2) of
        (Unit, Unit) => Unit
      | (R1, R2) => Struct [R1, R2])
   | best_one_rep_for_type (scope as {card_assigns, datatypes, ofs, ...}) T =
     (case card_of_type card_assigns T of
-       1 => if is_some (datatype_spec datatypes T)
-               orelse is_fp_iterator_type T then
+       1 => if is_some (datatype_spec datatypes T) orelse
+               is_fp_iterator_type T then
               Atom (1, offset_of_type ofs T)
             else
               Unit
      | k => Atom (k, offset_of_type ofs T))