Follow-up to Import a type family that is an operator in Haskell. This works: import GHC.TypeLits (type (+)) This is a parse error in GHC 9.0: import GHC.TypeL
I have a bunch of test modules and I can run a specific one using cabal test. cabal test Module.Name.Here The module contains many tests and one of them fails
The following video contains a mathematical card trick due to Colm Mulcahy: https://www.youtube.com/watch?v=dHzUQnRjbuM The key operation in the trick is define
I've read a few books on Haskell but haven't coded in it all that much, and I'm a little confused as to what Haskell is doing in a certain case. Let's say I'm u
I have installed ghc 9.2.1 via chocolatey on Windows 10. I tried to remove it with choco uninstall ghc and it says that one package has been removed. But I can
If first parameter is taken by the function first as function application is left-associative, for example: drop 2 [1,2,3,4] result: [3,4] is equivalent to (dr
Given: f1, f2 :: Fold Box (HashSet Thing) how do I write a fold that focuses the Things that are in f1 but not in f2? It would (of course) be the same Box, but
I am just learning Haskell. I am trying to present a number of spaces using a variable. For example, if I have a function: function (a,x,b) I
Long story short, I'd like some guidance on what's the (best) way to have Haskell work on Archlinux. By work I mean all, in terms of the ghci command line tool,
I'm compiling a haskell file with $ stack ghc --resolver lts-12.5 --package raw-strings-qq myscript.hs and execute it with $ ./myscript Killed $ on my Ub
I recently started learning Haskell and encountered a problem with the idea of Applicative. I need to make an implementation for newtype MyTriple a = MyTriple (
I have checked out https://github.com/gitpod-io/template-haskell and merged samples for a book (haskell in depth) into my branch. Prebuilding has no effect, eve
In Haskell there is a simple list function available iterate :: (a -> a) -> a -> [a] iterate f x = x : iterate f (f x) In python it could be implemen
I'm making drawings with the Haskell cairo binding and I want to align some object vertically. To do that, I need to know the width (the bounding box or partial
I'm trying to write Applicative for this type data Choice a = ColumnA a | ColumnB a I wrote a Functor instance: instance Functor Choice where fmap f (Co
I am pretty new to Haskell, and I was wondering if one can define new types that are defined by lists of other types. For example, I assume a string is defined
I have an instance of Num for a type I created called Vec: instance Num Vec where (+) (Vec x) (Vec y) = Vec (zipWith (+) x y) And I am trying to write a test
I have the following code which uses Newton's method to approximate the square root of some number. The problems is that when I run it, I get an error..What is
Is there anything in Haskell resembling the following type class? class Mergeable (f :: Type -> Type -> Type) where merge :: f a b -> f c d -> f (
Still not a hundred percent shure how to make instances of the more complex types. Have this: data CouldBe a = Is a | Lost deriving (Show, Ord) Made an ins