Geriving instances, generically. This module shares some of the underlying ideas and implementations of the generic-data package, allowing us to derive a bunch of instances using the underlying Generic implementation, but in a more declarative way.

In particular we introduc the Generically newtype wrapper to be used with '-XDerivingVia' to make derivation explicit. For example:

  data Foo = Foo
       deriving Generic
       deriving Eq via Generically Foo