val list : 'a arg -> 'a list arg
val none : string -> (unit -> unit) -> action
val one : string -> string * 'a arg -> ('a -> unit) -> action
val two : string -> string * 'a arg * string * 'b arg -> ('a * 'b -> unit) -> action
val list : 'a arg -> 'a list arg
val none : string -> (unit -> unit) -> action
val one : string -> string * 'a arg -> ('a -> unit) -> action
val two : string -> string * 'a arg * string * 'b arg -> ('a * 'b -> unit) -> action