Re: Functor => Pointed => Applicative => Monad

On 01/12/2010, at 13:04, Conor McBride wrote:

I was being slightly facetious. I was also wondering what value the Pointed class would add, by asking which instances of Functor would fail to be Pointed. The constantly Zero (or Void, if you insist) Functor? What else?

Any tuple type. Or, more generally, any multifunctor or anything that carries more information than just the a. Roman