In this post, we will see how to resolve The Writer monad and its type declaration Question: I am trying to get a better understanding of Monads and I am currently looking into the Write Monad in http://learnyouahaskell.com/for-a-few-monads-more#writer I don’t ...
In this post, we will see how to resolve Scala 2.13: Case class with extendable variable attributes? Question: I want to create a case class which can incorporate a record of string and another case class entity. For example: Now ...
In this post, we will see how to resolve How to derive a Generic.Aux if the case class has a type parameter – Shapeless Question: given: Is there a succint way to generate, for example, a Generic.Aux that will take ...
In this post, we will see how to resolve Can I always replace do … pure … with ado … in … in Purescript? Question: Can I always replace a do-block like this: where the last line is “pure” something, ...
In this post, we will see how to resolve Type class instance for case objects defined in sealed trait Question: In Scala 2.13 I have a case where I define some operation for all of types extending some sealed trait ...
In this post, we will see how to resolve How to change base class field in functional fashion in scala Question: Say I have this hierarchy and I want to define method with following signature that returns an instance of ...
In this post, we will see how to resolve Default Implementation of Coq typeclass methods Question: Is there a way you can provide default implementations of Coq typeclass methods like you can in Haskell? I saw no mention of this ...
Question: This might seem like a stupid question, but let’s say I have a Haskell type class C (a :: K) defined for some fixed kind K, and I know I have instances C a for all types a :: ...
Question: I’m trying to define my own Show class named MyShow, and want to ‘steal’ instances from TextShow and Prelude.Show, and prefer the former one if both exists. I tried following (showbPrec things is simplified to be focused): But I’m ...
Question: Haskell hobbyist here – is it possible to map a polymorphic constant over a list of types in a generic way? More precisely, consider this snippet: Unsurprisingly, this works as expected, i.e., it prints ["Int","Double"]. However, if I try ...