Re: Another important feature of Ada

[Karel Thoenissen <thoenissen@hello.nl>]

Ed Falis schreef:

> Jean-Pierre Rosen wrote:
>
> > The importance of separating specs from bodies is *not* the ability to
> > view them separatly, which can be accomplished with a tool as
> > you note. It is the ability to compile the spec, and compile users of
> > the spec before even thinking about the implementation.
> > Therefore you can check the spec, and check that the spec matches the
> > needs without being influenced by implementation constraints
> > (which often leads to over-specification).
>
> Yes, I should have mentioned that this is easily (and often) done in
> Eiffel using completely deferred classes with assertions.  A deferred
> class is similar to an abstract tagged type in a package.
>
> I agree with your point about the value of being able to compile against
> unimplemented specs - it's always been one of my favorite aspects of
> Ada.  But the same effect can be achieved otherwise.
>
> - Ed

True, but at the cost of doubling the number of classes in the hierarchy and
spilling the name space.



--

Groeten, Karel Th�nissen