Haskell has some very interesting type-level features, Servant is a great case-study in how they can be used to build a practical and feature rich library. This post walks through an example in an attempt to become more familiar with its inner workings.

type UsersIndex =
  Get '[JSON] [User]

type UsersShow =
  Capture "username" String
    :> Get '[JSON] User

type UsersAPI =
  "users"
    :> (UsersIndex :<|> UsersShow)

type Lens s t a b =
  forall f. Functor f =>
    (a -> f b) -> s -> f t

_1 :: Lens (a, c) (b, c) a b
_1 = _

_2 :: Lens (c, a) (c, b) a b
_2 = _

Gaining an understanding of the Lens type has been on my todo list for a long time. So I finally bit the bullet and read up a little. These are (more or less) my notes as I went along.

I sought to understand what the fuss was all about and I’ve now added to the mass of Monad Explainer posts on the internet.

readAFile().then(function (content) {
  return writeAFile(content)
}).then(function (report) {
  console.log(report)
})

Petrichor (/ˈpɛtrɨkɔər/) is the earthy scent produced when rain falls on dry soil. The word is constructed from Greek, petra, meaning ‘stone’, + ichor, the fluid that flows in the veins of the gods in Greek mythology.

— Wikpedia

I don’t have the original images anymore, but this made a rad gif also…

Everything is connected, and the way it connects is kinda complex. I’d like to be more aware of my connections to people and the networks they’re a part of.

As it stands these are all mock-ups rendered in SketchUp, the dream plan is to get this rendering in the browser from user input. Wild scaffolding.