[Haskell-cafe] Representing Hierarchies with Typeclasses

[Rahul Muttineni]

Hi Dimitri,

Thanks for the link! I'll take a look. The goal of doing this was to make
foreign Java imports reusable for subclasses in GHCVM.

Thanks,
Rahul

On Wed, Oct 5, 2016 at 7:25 PM, Dimitri DeFigueiredo <
defigueiredo at ucdavis.edu> wrote:

> I have looked at how to embedded object oriented systems into haskell
> for practical reasons.
> By far the best resource I found was Oleg Kiselyov and Ralph Lämmel's work:
>
> https://arxiv.org/pdf/cs/0509027.pdf
>
> It shows the multiple possibilities.
> I have used the idea of having a super class be a polymorphic type with
> a tail.
>
> data Point s = Pt { x :: Int, y:: Int, tail :: s}
>
> And then specializing the parameter s into your derived class
>
> type Radius = Int
> type Circle = Point Radius
>
> many times.
>
> But *be warned*, I try to avoid object hierarchies like the plague! They
> lead to code that is not reusable.
> You may want to consider other simpler possibilities. Here is one of my
> earlier experiments that may be useful to you (I no longer have the
> views expressed there).
>
> https://github.com/dimitri-xyz/inheritance-in-haskell
>
> Cheers,
>
> Dimitri
>
> --
> 2E45 D376 A744 C671 5100 A261 210B 8461 0FB0 CA1F
>
>
>


-- 
Rahul Muttineni
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20161005/0547d9a3/attachment.html>