I\'ve seen many people complaining about some of the type classes from the standard library saying things like \"Monad should require Functor\" or even \"Monad should require Applicative\", \"Applicat
The following type signature to find the magnitude of a vector represented as a tuple doesn\'t seem to work:
Let there are classes Fruit, Orange, and Apple. abstract class Fruit class Orange extends Fruit class Apple extends Fruit
I would like to have a type class of types that can possibly casted to other types when possible. class Castable a b where
I\'m trying to write Eric Kidd\'s and Sigfpe\'s code for a probability monad using Data.Map as a backend but I\'m stuck with a Functor instance.
Let\'s say I have: data MyType myToDouble :: MyType -> Double Let\'s say I want MyType to b开发者_开发知识库e an instance of Num or Real or something that Double is already an instance of.
It appears to be impossible to introspect type class constraints on functions and data types and such. However, ghci appears to do it.开发者_JAVA技巧
My specific problem is actually not about the general translation of an OO interface to Haskell. This is just the best title I could come up with. Yet, I\'m sure that my problem originates from a stil
Code is below. I\'d like to have parameters to my function that are only restricted by type class. I call a function of the type class on them and then I can use them. But I\'m getting various errors
In my free time I\'m learning Haskell, so this is a beginner question. In my readings I came across an example illustrating how Either a is made an instance of Functor:
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