struct     type t = {       params: string list;      

(** Catch-all list of parameters to be concatted together and passed to the command. *)

      with_headers: bool;      

(** The header of A will be prepended to the output. -header. *)

      unique_features: bool;    

(** Write the original A entry one if any overlaps found in B. *)

    }     let default = { params = []; with_headers = true; unique_features = true; }     let render {params; with_headers; unique_features; } =       (if with_headers then " -header " else " ")       ^ (if unique_features then " -u " else " ")       ^ (String.concat ~sep:" " params)   end