type spec =
| Unit of unit -> unit
| Bool of bool -> unit
| Set of bool ref
| Clear of bool ref
| String of string -> unit
| Set_string of string ref
| Int of int -> unit
| Set_int of int ref
| Float of float -> unit
| Set_float of float ref
| Tuple of spec list
| Symbol of string list * string -> unit
| Rest of string -> unit
| Rest_all of string list -> unit
| Expand of string -> string array
type anon_fun = string -> unit
val read_arg : string -> string array
val read_arg0 : string -> string array
val write_arg : string -> string array -> unit
val write_arg0 : string -> string array -> unit