type t = {mutable symbol : string option;mutable exchange : string option;mutable trade_account : string option;mutable client_order_id : string option;mutable order_type : Dtcprotocol_piqi.order_type_enum option;mutable buy_sell : Dtcprotocol_piqi.buy_sell_enum option;mutable price1 : Dtcprotocol_piqi.float64 option;mutable price2 : Dtcprotocol_piqi.float64 option;mutable quantity : Dtcprotocol_piqi.float64 option;mutable time_in_force : Dtcprotocol_piqi.time_in_force_enum option;mutable good_till_date_time : Dtcprotocol_piqi.int64_fixed option;mutable is_automated_order : bool option;mutable is_parent_order : bool option;mutable free_form_text : string option;mutable open_or_close : Dtcprotocol_piqi.open_close_trade_enum option;mutable max_show_quantity : Dtcprotocol_piqi.float64 option;}