module Printer: sig endval day_name : (Date.day -> string) Pervasives.refval name_of_day : Date.day -> stringval short_name_of_day : Date.day -> stringval month_name : (Date.month -> string) Pervasives.refval name_of_month : Date.month -> stringval short_name_of_month : Date.month -> stringmodule type S = sig endmodule DatePrinter: sig endmodule TimePrinter: sig endmodule CalendarPrinter: sig end