[Ocaml-lib-devel] IO oo wrappers

[Nicolas C. <war...@fr...>]

Here's some OO wrappers proposal for IO module.

As Yamagata Yoriyuki suggested, theses can be useful in order to provide
ExtLib IO compatibility without the need to add a dependency to IO module
(that's one - the only ? - nice thing with objects, since their type are not
module-bounds). If success, I'm planing also to add this for Enums.

Regards,
Nicolas Cannasse

(** MLI **)

class ['a,'b] o_input : ('a,'b) input ->
  object

 method read : 'a
 method nread : int -> 'b
 method pos : int
 method available : int option
 method close : unit

  end

class ['a,'b,'c] o_output : ('a,'b,'c) output ->
  object

 method write : 'a -> unit
 method nwrite : 'b -> unit
 method pos : int
 method flush : unit
 method close : 'c

  end

val from_in : ('a,'b) #o_input -> ('a,'b) input
val from_out : ('a,'b,'c) #o_output -> ('a,'b,'c) output

(** ML **)

class ['a,'b] o_input (ch:('a,'b) input) =
  object

 method read = read ch
 method nread n = nread ch n
 method pos = pos_in ch
 method available = available ch
 method close = close_in ch

  end

class ['a,'b,'c] o_output (ch:('a,'b,'c) output) =
  object

 method write x = write ch x
 method nwrite x = nwrite ch x
 method pos = pos_out ch
 method flush = flush ch
 method close = close_out ch

  end

let from_in ch =
 create_in
  ~read:(fun () -> ch#read)
  ~nread:ch#nread
  ~pos:(fun () -> ch#pos)
  ~available:(fun () -> ch#available)
  ~close:(fun () -> ch#close)

let from_out ch =
 create_out
  ~write:ch#write
  ~nwrite:ch#nwrite
  ~pos:(fun () -> ch#pos)
  ~flush:(fun () -> ch#flush)
  ~close:(fun () -> ch#close)