module Extended_date: sig .. end
sig
end
val format : ?ofday:Core.Std.Time.Ofday.t -> string -> Core.Std.Date.t -> string
?ofday:Core.Std.Time.Ofday.t -> string -> Core.Std.Date.t -> string
format "%Y-%m-%d" t will return "YYYY-MM-DD"
format "%Y-%m-%d" t