class type mime_body_ro =object..end
 The value of the body can be returned either as string, or as
 object channel. Both ways are possible independently of where
 the value is stored, in-memory, or as external file.
method value : stringvalue method returns the _decoded_ body,
 i.e. transfer encodings are removed before the value is passed
 back.
 When the body is stored in an external file, this method
 reads the complete file into memory.
method store : storemethod open_value_rd : unit -> Netchannels.in_obj_channel let ch = body # open_value_rd () in
 try
   while true do
     let line = ch # input_line() in
     ... (* do something *)
   done;
   assert false; (* never reached *)
 with
   End_of_file ->
     ch # close_in()
 
 As value, this method returns the value in decoded form.
 This method is quite economical with the resources, and takes
 only as much memory as needed for the channel operations.
method finalize : unit -> unit