module Focus_dir : sig ... endmodule Margin : sig ... endmodule Scroll_region : sig ... endmodule Float_type : sig ... endmodule Scroll_result : sig ... endmodule Scroll : sig ... endval move_focus : ('key, 'value, _) Core_kernel.Map.t ‑> 'key option ‑> Focus_dir.t ‑> ('key * 'value) optionmove_focus gives the next element starting from the given key in the given direction
according to the order of elements in the map.
If the given key is None, move_focus returns the first element in the map for
direction Next, and the last element in the map for direction Prev.
If the given key is already the last element in the table for direction Next, or the
first element in the table for direction Prev, then move_focus returns None.