Re: How come Ada isn't more popular?

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

On Tue, 06 Feb 2007 16:44:17 +0100, Markus E Leypold wrote:

> Maciej Sobczak <no.spam@no.spam.com> writes:
> 
>> Sure. But for the sake of discussion completeness, you might wish to
>> throw an example of a situation where scoped lifetime will not make it.
> 
> Model-View-Controller in GUIs. Especially trying to adapt that to GTKAda.

I am not sure what you mean, but

1. GTK+ uses reference counting. GtkAda just follows it in that respect. So
all GtkAda interface objects are access to class-wide record. These objects
are scoped. Because GtkAda is thin bindings its objects are not controlled
(neither they are in GTK+). It would be quite easy to make them controlled
and perform Unref upon Finalization.

2. MVC tree view is not different in that respect and does not impose any
additional difficulties except usual awkward interfacing with C.

You can find custom tree view models for GtkAda here:

   http://www.dmitry-kazakov.de/ada/gtkada_contributions.htm#2.1

and custom cell renderers here:

   http://www.dmitry-kazakov.de/ada/gtkada_contributions.htm#2.3

>> OK, I accept the word "peculiar". I only oppose "quite a clean
>> concept" in your previous post. :-)
> 
> Tha Ada OO way. 'Controlled' is just the logical consequence and on
> top of tagged types quite clean. 

Controlled is a hack. It is the logical consequence of an apparent desire
to leave this issue open for future language extensions.

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