Re: Usage of Interfaces with Ada 95

[Simon Wright <simon@pushface.org>]

Matthew Heaney <matthewjheaney@earthlink.net> writes:

> Michael Erdmann <Michael.Erdmann@snafu.de> writes:
> 
> > This is not the point! The point is, that i like to setup a 
> > repository of concepts, which is specialized when it is used.
> > For example, the iterator (or enumerator) is a very general
> > concept which requieres basicaly the following methods
> > 
> >     First          - Return the first element

This will have a problem in Ada since you'll be treating the iterator
as an in out parameter to what otherwise looks like a function.

> >     Next           - Fetch the next element
> >     HasMoreElement - Check if there is more
> > 
> > 
> > By introducing a set of concepts i like to standarize the coding.

> For example, all the containers and iterators in the Charles library
> reify your iterator concept above.  So what's the problem?  That
> library does exactly what you want, which is to iterate over the
> elements in a container.

And so do Booch Component iterators, which are abstract, and which of
course are much more like what all English-speaking programmers bar
those who also speak STL understand by Iterator than the STL ones
which Charles has adopted. I just have to get that dig in. And there
are some on the ARG who have similar views. We shall have to see how
it goes! Personally I have no problem at all with what the STL does,
just some of the names it's adopted for the concepts ..