Generics and Constrained Polymorphism versus Subtyping

Posted by Rahul G on Stack Overflow See other posts from Stack Overflow or by Rahul G
Published on 2010-04-25T04:41:19Z Indexed on 2010/04/25 4:43 UTC
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scala

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haskell

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functional-programming

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oop

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programming-languages

Hullo all.

In this (Warning: PDF) presentation on Haskell Type Classes, on slide #54, there's this question:

Open Question:

In a language with generics and constrained polymorphism, do you need subtyping too?

My questions are:

How do generics and constrained polymorphism make subtyping unnecessary?
If generics and constrained polymorphism make subtyping unnecessary, why does Scala have subtyping?

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