Lennart Augustsson wrote:
>
> Kevin Atkinson wrote:
>
> > I am sorry for the naive question but how do you fell about adding
> > dynamic binding to Haskell to make it possible to have heterogeneous
> > lists with out having to use a nasty union type which has a number of
> > problems.
> >
>
> What you want(?) is existential types. Most implementations support
> this.
Maybe? What exactly are they. I have not been able to find a good
guide which explains the forall and exists qualifier concepts.
What I want to be able to do is store a bunch of objects with a common
base class in a list. And I also want to be able to add types to this
heritage without having to modify a single line of the existing code.
--
Kevin Atkinson
[EMAIL PROTECTED]
http://metalab.unc.edu/kevina/
