Re: [Haskell-cafe] How to fulfill the "code-reuse" destiny of OOP?

On 30/10/09 05:32, Rogan Creswick wrote:

On Thu, Oct 29, 2009 at 6:54 PM, Magicloud Magiclouds wrote:

...

My concern here is about the data member inheriting. In OOP, when I inherit a class, I also got the members of it. But in haskell, how to inherit a "data"?

[..]

The point of that whole rant is that extending data-bearing classes isn't necessarily a good idea, so before trying to find a way to do it with haskell, it may be better to just encapsulate another data type, which is trivial:

data InnerThing = A | B | C

data OuterThing = Outer { innerThing :: InnerThing, otherField :: Int }

IIRC James Gosling once said that if he were to design Java today he would leave out classes. I suppose partly due to many of the issues with "data inheritance". /M -- Magnus Therning (OpenPGP: 0xAB4DFBA4) magnus＠therning．org Jabber: magnus＠therning．org http://therning.org/magnus identi.ca|twitter: magthe