Re: Ada2005

[dmitry@elros.cbb-automation.de (Dmitry A. Kazakov)]

On Wed, 19 Dec 2001 18:20:41 GMT, "Mark Lundquist"
<no.spam@getalife.com> wrote:

>
>"Ray Blaak" <blaak@telus.net> wrote in message
>news:uvgf5rb15.fsf@telus.net...
>> dmitry@elros.cbb-automation.de (Dmitry A. Kazakov) writes:
>> > However, what people criticizing Ada usualy want, is just a syntax
>> > sugar, which would allow to refer methods using postfix form if there
>> > is only one dispatching [or class-wide] argument and it is the first
>> > one.
>>
>> Like me.
>>
>> > I think in a future revision there could be some variant of rename
>> > statement which would allow to do this and also the opposite thing
>> > [for "methods" of protected objects and tasks which are always called
>> > using the postfix form]. For instance:
>> >
>> > type Ellipse is tagged ...
>> > procedure Draw (Figure : Ellipse, Where : Point);
>> > entry Ellipse.Draw (Where : Point) renames Draw;
>>
>> Why not make it automatic? The extra declaration is tedious and requires
>extra
>> maintenance.
>>
>> Given:
>>
>>   e : Ellipse;
>>
>> then have
>>
>>   e.Draw(p)
>>
>> be valid iff Draw exists with an Ellipse as its first parameter.
>>
>> Then it is truly just an alternate syntax to be used if desired, and not
>used
>> if not.
>>
>
>Doesn't it make a mishmash of the name resolution rules?  Consider
>
>        type Note is private;
>
>        function Pitch (Subject : Note) return Note_Properties.Pitch;
>        function Length (Subject : Note) return Note_Properties.Length;
>
>    private
>
>        type Note is record
>            Pitch : Note_Properties.Pitch;
>            Length : Note_Properties.Lenght;
>        end record;
>
>In the body of the package, how do you resolve the name "X.Pitch" for an X
>of type Note?

We already have this case with protected types:

protected type X is
    function Y return Integer;
private
    Y : Integer;  -- Illegal!
end X;

Thus the compiler should complain about:

Pitch : Note_Properties.Pitch;

Regards,
Dmitry Kazakov