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Comment by pjmlp | Hacker News Reader

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pjmlp·

> How are type classes in Haskell an OO feature?

See https://news.ycombinator.com/item?id=8280613

There are so many ways of doing OO.

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Depends on how you define OO. My own definition of object involves identity and corresponding encapsulated state, which is something that Haskell doesn't support directly (since identity isn't pure).

Sure, but given your backgound, I imagine you are fully aware that back in the early 90's the OO community was quite divided about what are actually the core concepts and their implementation.

So, what OO is all about will depend which researcher gets asked.

True. And in the end, this even applies to functional or declarative programming

Oh, fully agreed. I think my main point was that OO in a language such as OCaml has very little to do with OO in a language such as Scala (or Java). I'm agreeing with the OP that the marriage of OO and FP in Scala is problematic.

Yes, we can use less currently mainstream (note: not less correct) definitions of OO, but that doesn't help the Scala=OO+FP position.

Just like languages have versions/revisions, e.g: C++11,C++14, Java8 ...etc, having versions at major changes during evolution of OO might have helped in creating reference points which can facillitate discussions and enhance understanding i.e. like OO98, 0099, OO2005 ...etc.

That's impossible, because what would you write in OOxx, given the different CS views and programming models on the subject?

Jump dump what is being worked on at any given point in time?

For me it is hard to grasp how youngsters see OO or FP, because I was part of the initial mainstream waves. So I got to see the things in a different perspective.

The world at companies was procedural, and lots of experimentation was going on.

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