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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: The simple Image issue
Date: Wed, 31 Aug 2011 18:07:42 +0200
Organization: cbb software GmbH
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Date: 2011-08-31T18:07:42+02:00
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On Wed, 31 Aug 2011 11:53:17 -0400, Hyman Rosen wrote:

> On 8/31/2011 2:16 AM, Georg Bauhaus wrote:
>> In which way would you change T'Value for symmetry?
> 
> You wouldn't, because the symmetry is false. When you
> already have an object, being forced to name its type
> is silly and redundant. When you have a string and want
> it converted to an object, of course you need to say
> what type it's becoming.

However type conversion is another beast. If I designed the language I
would support ad-hoc subtypes (ones established dynamically in some scope
without implementation inheritance). E.g. in some context one could make
Integer a subtype of String and just write:

   I : Integer;
   ...
   Put_Line ("I=" & I);

Static type relationships, even with MI and MD support, are not flexible
enough to handle cases like I/O, containers etc in a generic way. You need
an ability to create a virtual parent for unrelated types later on to be
able to have a class of these types (on order to define operations handling
instances from this class).

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