QuantifiedConstraints1 has landed in GHC 8.6, I am reading Deriving Type Classes (section 7)2 where it was first suggested. However I can't understand, in operational terms, how QuantifiedConstraints are translated into dictionaries. Following is the excerpt from the paper.
I am trying to understand the numeric type class hierarchy in Haskell. The basic numeric type isAs a side note, according to some of my sources (slides), it should actually be
We often use type class dependence to emulate the sub typing relationship.e.g:when we want to express the sub typing relationship between Animal, Reptile and Aves in OOP:
I'm trying to write an Eq instance for this data type:I wrote the trivial code I thought that would work:
I expect the following behavior from the applicative instance of my ZipList':This was my first attempt: