I wanted to implement a Custom Datatype named ComplexNumber like this: data ComplexNumber a = C (a,a) Now I wanted to implement the Monoid Variable ...
I wanted to implement a Custom Datatype named ComplexNumber like this: data ComplexNumber a = C (a,a) Now I wanted to implement the Monoid Variable ...
I'm exploring the Typescript type system by implementing the Fantasy Land Spec and I ran into an issue while trying to implement the spec for Semigrou ...
The base library in Haskell has the following type synonyms in Data.Semigroup: type ArgMin a b = Min (Arg a b) type ArgMax a b = Max (Arg a b) He ...
Why does Semigroup has an Option type and None behave like a neutral element in Monoid? ...
Given an operation (??) such that (that is to say (??) is associative) must it be the case that (that is to say that liftA2 (??) is associative ...
I want to make the data type Moneda a instance of the Semigroup, and implement the associative operation as +. I'm having difficulties understanding i ...
I have a list of hashMaps as follows : I want to merge these HashMaps into a single HashMap as : I have tried listHashMaps.flatten.ToHashMap ...
The program can sort the list by Mfg or by Year. What is (<>)? ...
A semigroup is required to be associative, but I could define a Semigroup like: I am able to implement plus which is not associative, yet the class ...
Lets see declaration of a new data type used to deal with reverse list in Haskell: The problem I'm troubled with is a compilation failure which des ...
I am looking for most common Haskell library that introduces [a] wrapper that instantiates Semigroup by delegating mappending to its elements in the s ...
I'm trying to understand the relationship between a functor and a monoid. They are often mentioned together but I haven't been able to quite connect t ...
Using cats.Semigroup one can write this: import cats.Semigroup import cats.implicits._ val l1: String Either Int = Left("error") val r1: String Eith ...
Cannot understand the actual difference between Semigroupal.product and Semigroupal.tuple2. Here is a short example: With invalids both bothInvalid ...
I am trying to make a tic-tac-toe game, and I decided to construct types for cells (elements of the board) and the board as follows: Here, Nothing ...
The following function - Is a (less efficient) generalization of Data.Set.isSubSetOf. It checks if the first argument is "contained" in the second ...
In the exercises of Haskell Programming from First Principle book on Semigroup, I am asked to write quickCheck for user defined typeclasses. There are ...
I'm trying to convert an Haskell Semigroup to Scala. The Haskell code works fine but I can't write it in Scala Haskell: import Data.Semigroup newty ...
Maybe expresses computations that might not produce a result due to an error. Therefore such computations must be short circuited. Now Maybe's Semigr ...
I may have been under the false impression that Haskell is lazier than it is, but I wonder if there's a way to get the best of both worlds... Data.Mo ...