src/HOL/Tools/Nitpick/nitpick_scope.ML

     val cards_asgns = fix_cards_assigns_wrt_boxing thy mono_Ts cards_asgns
     val blocks = blocks_for_types ext_ctxt cards_asgns maxes_asgns iters_asgns
                                   bisim_depths mono_Ts nonmono_Ts
     val ranks = map rank_of_block blocks
     val all = all_combinations_ordered_smartly (map (rpair 0) ranks)
-    val head = (uncurry take) (max_scopes, all)
+    val head = take max_scopes all
     val descs = map_filter (scope_descriptor_from_combination ext_ctxt blocks)
                            head
   in
     (length all - length head,
      descs |> length descs <= distinct_threshold ? distinct (op =)