Nstreamtype token = {region : Pos.Region.t;token : Approx_lexer.token;newlines : int;between : string Lazy.t;substr : string Lazy.t;offset : int;}val of_string : ?start_pos:Pos.Position.t -> ?start_offset:int -> string -> tval of_channel : ?start_pos:Pos.Position.t -> in_channel -> t