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Icelandjack / Yoneda_II.markdown
Last active August 11, 2023 20:10
Yoneda Intuition from Humble Beginnings
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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.

View Modern FP with mtl.hs
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
import Control.Monad.IO.Class
import Control.Monad.Trans.Class
import Prelude hiding (log)
-- The API for cloud files.
class Monad m => MonadCloud m where
saveFile :: Path -> Bytes -> m ()
runarorama / gist:a8fab38e473fafa0921d
Last active April 13, 2021 22:28
Compositional application architecture with reasonably priced monads
View gist:a8fab38e473fafa0921d
sealed trait Interact[A]
case class Ask(prompt: String)
extends Interact[String]
case class Tell(msg: String)
extends Interact[Unit]
trait Monad[M[_]] {
def pure[A](a: A): M[A]
gcatlin / gist:1847248
Created February 16, 2012 19:43
Install specific version of Homebrew formula
View gist:1847248
brew update
brew versions FORMULA
cd `brew --prefix`
git checkout HASH Library/Formula/FORMULA.rb # use output of "brew versions"
brew install FORMULA
git checkout -- Library/Formula/FORMULA.rb # reset formula
## Example: Using Subversion 1.6.17