Questions for typeclass


5197

How should types be used in Haskell type classes?

I'm new to Haskell, and a little confused about how type classes work. Here's a simplified example of something I'm trying to do:
9240

Exporting a polymorphic MonadState function for a particular state data type

What I'm trying to do is (in a module I'm writing) export a function that works on a particular type in a state monad (in the example below, that type would be Foo). However I would like the user t...
7305

Haskell Typeclass shorthand

So, I have a pair of typeclasses that I'll be using a lot together, and I want to avoid specifying both each time. Basically, instead of putting
2561

How to make a type an instance of Eq

I have a data type called Praat. I want Praat to be an instance of Eq so that two Praats are equal if and only if mx are equal. How does one do this?
1641

multiple type parameters in haskell type classes

I'm trying to do some abstraction in Haskell98 but doen't know how to do it.
2877

Choose a typeclass based on return type

I want to be able to have a function, which implementation will choose a typeclass based on the manual type specification of it's return type.
4208

How do I create a ListIsomorphic instance for Vector.Unboxed?

Since it seems that writing a ListIsomorphic instance for generic vectors is impossible (or not a good idea), I'm trying to write one for Vector.Unboxed directly.
8796

Provide type-class when implementing/override method

I would prefer to work more with type-classes but having some issues:
679

Multi-parameter type synonym instances

I'm trying to figure out if it's possible (and how) to define class instances for multi-parameter type synonyms.
3874

Haskell ghci read behaviour with * and max

So I've just encountered the following in ghci:
3081

How to create ListIsomorphic instances for tuples and packed types?

Sorry, this is yet another topic in the same serie. I have a typeclass for things that are isomorphic to lists:
7628

Haskell ad hoc polymorphism

I'm trying to get my head around ad-hoc polymorphism in haskell, that is having the same function provide different behaviour for different argument types.
5131

Haskell: Why is there no type mismatch (and why does this compile)?

I was so sleepy that I wrote the following code (modified to just show the confusion):
2570

Facilities for generating Haskell types in Haskell (“second order Haskell”)?

Apologies in advance if this question is a bit vague. It's the result of some weekend daydreaming.
3805

Flexible instances needed?

I want to write a Convertible instance for a Haskell type to it's C representation

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