Re: Ada.Storage_IO: applied example?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Wed, 24 Oct 2012 07:03:43 +0200, J-P. Rosen wrote:

> Le 23/10/2012 22:28, Dmitry A. Kazakov a �crit :
>> On Tue, 23 Oct 2012 21:42:43 +0200, Yannick Duch�ne (Hibou57) wrote:
>> 
>>> I'm seeking for a tiny use case showing `Ada.Storage_IO` in action.
>> 
>> It looks useless at first glance. The buffer size is fixed and
>> implementation defined(!). Why would anybody use that rather than plain
>> array?
>> 
> Imagine you want to implement a binary IO package. On one side you have
> high level data type, on the other side system files that are just
> blocks of bytes. Storage_IO allows you to bridge this gap (at least
> that's my understanding).

In that case the package should rather define conversions to and from
Storage_Array, better as in-place operations with a position to get/put
data at. Furthermore the generic parameter should have been declared as:

   type Element_Type (<>) is private.

And, of course, implementation-defined I/O is a bad idea anyway in modern
times of interoperability. (This also applies to Direct_IO and
Sequential_IO, which are remnants of late 70's.)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de