Re: user-defined type conversion

[18k11tm001@sneakemail.com (Russ)]

18k11tm001@sneakemail.com (Russ) wrote in message news:<bebbba07.0205201126.572c9f09@posting.google.com>...
> "David C. Hoos, Sr." <david.c.hoos.sr@ada95.com> wrote in message news:<mailman.1021892102.6644.comp.lang.ada@ada.eu.org>...
> > ----- Original Message ----- 
> > From: "Russ" <18k11tm001@sneakemail.com>
> > Newsgroups: comp.lang.ada
> > To: <comp.lang.ada@ada.eu.org>
> > Sent: May 19, 2002 10:25 PM
> > Subject: Re: user-defined type conversion
> > 
> > > I still don't see why I shouldn't be able to make my own type/unit
> > > conversion that has the same simple syntax as the built-in type
> > > conversions. Until I do, I consider it a minor deficiency of the
> > > language.
> > Do you understand now?
> 
> Yes, I understand now. But I think Ada should have been designed to
> first check for a user-defined type conversion before using a
> compiler-generated conversion. That would solve the ambiguity problem
> and allow users to create their own type/unit conversions with the
> same syntax as built-in type conversions. That, in turn, would allow
> developers to create simple and elegant type/unit system for each
> particular application.

After reading the replies here and thinking about it a bit more, I
have come to the conclusion that it is not such a great idea after all
to have user-defined type conversions with the same syntax as built-in
conversions.

The problem is that it is error prone. I could carelessly try to
invoke my user-defined conversion on a type that I have not defined it
for, and the compiler would not be able to detect the error (because
it would just use the built-in conversion).

There's hope for me after all.