Re: function Is_Open (File : File_Type) return Boolean; :Text_io

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

On Thu, 29 Oct 2015 04:25:06 -0700 (PDT), AdaMagica wrote:

> Am Mittwoch, 28. Oktober 2015 22:02:17 UTC+1 schrieb Dmitry A. Kazakov:
>>> In Ada, we can write:
>>> 
>>>     type Gizmo_Count is range 0 .. 2**10;
>>>     Num_Gizmos: Gizmo_Count := 0;
>>> 
>>> IMHO, documenting the 0..1024 requirement in executable code is much
>>> better than using a comment:
>> 
>> How is that documenting? It is a direct instruction to the compiler.
>> Documentation is addressed to the human reader.
>> 
>> The advantage of Ada over C is that where in Ada you can instruct, in C the
>> only way is to document.
> 
> IMHO, this is again a case of Dmitry's special nomenclature:

It is the standard meaning of the word: to record something in written,
graphic or other form; to support or accompany with documentation.

> I think the Ada community has a different bias: Expressing requirements,
> i.e. documentation, in code is preferable.

Actually there are people in c.l.a. against excessive commenting.

> Thus we use Natural rather than
> Integer  for counting, use constraints like above in Gizmo. And we call
> this *documenting*. This is both, an instruction for the compiler *and*
> information addressed to the reader.

So, according to you

   X : Integer;  -- Undocumented
   Y : Natural; -- Documented

Don't you find it a bit silly? There is no difference between both.

BTW, any numeric type in Ada is constrained => "documented", according to
you.

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