What are some common mistakes when using type classes in Haskell?

What are some common mistakes when using type classes in Haskell?

Some common mistakes include misunderstanding instance declarations, not using overlapping instances correctly, and failing to leverage type inference.

Can you explain what overlapping instances are?

Overlapping instances occur when two or more type class instances could match the same type. This can lead to ambiguity.

How can I avoid issues with overlapping instances?

To avoid issues, you can use the {-# OVERLAPPING #-} and {-# OVERLAPPABLE #-} pragmas to control which instance should be chosen.

What about type inference? How does it relate to type classes?

Type inference allows Haskell to automatically deduce the types of expressions. Misunderstanding it can lead to unnecessary type annotations.

Any tips for debugging type class issues?

Use GHC's -Wall flag to enable warnings, and consider using the :t command in GHCi to check types of expressions.