i-am-tom

const Day = ({ get, left, right }) => {
  const map = f => Day ({
    get: f (extract()),

    left, right
  })

  const extend = f =>
    Day ({
      get: (left, right) => f (Day ({ get, left, right })),

Icelandjack

(previous Yoneda blog) (reddit) (twitter)

Yoneda Intuition from Humble Beginnings

Let's explore the Yoneda lemma. You don't need to be an advanced Haskeller to understand this. In fact I claim you will understand the first section fine if you're comfortable with map/fmap and id.

I am not out to motivate it, but we will explore Yoneda at the level of terms and at the level of types.

chrisanthropic

Download the image builder

• git clone [email protected]:Robertof/nixos-docker-sd-image-builder.git
• cd nixos-docker-sd-image-builder

Configure for Raspi4

• modify /config/rpi4/default.nix to increase size of boot partition
  • this step is optional but I ran out of space in /boot pretty quickly with the default setting since I'm still learning and rebuilding a lot. Let's leave some room for trial & error.
  • sdImage.firmwareSize = 1024;
• modify /config/sd-image.nix
• ./rpi3 becomes ./rpi4