I would like to understand the key difference between parametric polymorphism such as polymorphism of generic classes/functions in the Java/Scala/C++ languages and "ad-hoc" polymorphism in the Haskell type system. I'm familiar with the first kind of languages, but I have never worked with the Haskell. More precisely: How is type inference algorithm e.g. in Java different from the type inference in Haskell? Please, give me an example of the situation where something can be written in Java/Scala but can not be written in Haskell(according to the modular features of these platforms too), and vice-versa. Thanks in advance.

Parametric polymorphism vs Ad-hoc polymorphism

I would like to understand the key difference between parametric polymorphism such as polymorphism of generic classes/functions in the Java/Scala/C++ languages and "ad-hoc" polymorphism in the Haskell type system. I'm familiar with the first kind of languages, but I have never worked with the Haskell.

More precisely:

How is type inference algorithm e.g. in Java different from the type inference in Haskell?
Please, give me an example of the situation where something can be written in Java/Scala but can not be written in Haskell(according to the modular features of these platforms too), and vice-versa.

Thanks in advance.

Parametric polymorphism vs Ad-hoc polymorphism

3 Answers