When I see stuff like:

runMVC
    :: s                               -- Initial state
    -> Model s a b                     -- Program logic
    -> Managed (View b, Controller a)  -- Impure output and input
    -> IO s                            -- Returns final state

It really crystallizes why I’m so interested in Haskell. This sort of definition of a whole paradigm (MVC) is clear in ways that I’ve not previously seen. This is concrete and, even if I don’t grok all the intricacies yet, it’s not just a handwavey description of an architecture.

Thanks for the link.