Reason · Reason lets you write simple, fast and quality type safe code while leveraging both the JavaScript & OCaml ecosystems.

sig
 type spec =
   Unit of (unit -> unit)
  | Bool of (bool -> unit)
  | Set of bool Stdlib.ref
  | Clear of bool Stdlib.ref
  | String of (string -> unit)
  | Set_string of string Stdlib.ref
  | Int of (int -> unit)
  | Set_int of int Stdlib.ref
  | Float of (float -> unit)
  | Set_float of float Stdlib.ref
  | Tuple of Arg.spec list
  | Symbol of string list * (string -> unit)
  | Rest of (string -> unit)
  | Rest_all of (string list -> unit)
  | Expand of (string -> string array)
 type key = string
 type doc = string
 type usage_msg = string
 type anon_fun = string -> unit
 val parse :
  (Arg.key * Arg.spec * Arg.doc) list ->
  Arg.anon_fun -> Arg.usage_msg -> unit
 val parse_dynamic :
  (Arg.key * Arg.spec * Arg.doc) list Stdlib.ref ->
  Arg.anon_fun -> Arg.usage_msg -> unit
 val parse_argv :
  ?current:int Stdlib.ref ->
  string array ->
  (Arg.key * Arg.spec * Arg.doc) list ->
  Arg.anon_fun -> Arg.usage_msg -> unit
 val parse_argv_dynamic :
  ?current:int Stdlib.ref ->
  string array ->
  (Arg.key * Arg.spec * Arg.doc) list Stdlib.ref ->
  Arg.anon_fun -> string -> unit
 val parse_and_expand_argv_dynamic :
  int Stdlib.ref ->
  string array Stdlib.ref ->
  (Arg.key * Arg.spec * Arg.doc) list Stdlib.ref ->
  Arg.anon_fun -> string -> unit
 val parse_expand :
  (Arg.key * Arg.spec * Arg.doc) list ->
  Arg.anon_fun -> Arg.usage_msg -> unit
 exception Help of string
 exception Bad of string
 val usage : (Arg.key * Arg.spec * Arg.doc) list -> Arg.usage_msg -> unit
 val usage_string :
  (Arg.key * Arg.spec * Arg.doc) list -> Arg.usage_msg -> string
 val align :
  ?limit:int ->
  (Arg.key * Arg.spec * Arg.doc) list ->
  (Arg.key * Arg.spec * Arg.doc) list
 val current : int Stdlib.ref
 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
end