ChristopherDavenport

import cats._
import cats.implicits._
import cats.effect._
import cats.effect.implicits._
import scala.concurrent.duration._
import io.chrisdavenport.mapref._


trait SetOnceCache[F[_], K, V]{
  def get(k: K): F[V]

ChristopherDavenport

package io.chrisdavenport.shapelessless

import cats._
import cats.syntax.all._
import cats.effect._

import scala.deriving._
import scala.compiletime._
import org.tpolecat.typename._

minad

Polyp: Small child of the Hydra

;; The undo keybindings `C-x u` and `C-_` enter the polyp.
(defpolyp polyp-undo
  "_u_ndo  _r_edo"
  ("u" undo-fu-only-undo "C-x u" "C-_")
  ("r" undo-fu-only-redo))

alphapapa

amohrland

module plfa.part1.Naturals where

data N : Set where
  zero : N
  suc : N -> N

{-# BUILTIN NATURAL N #-}

import Relation.Binary.PropositionalEquality as Eq
open Eq using (_≡_; refl)

ChristopherDavenport

scalaVersion := "2.13.1"

enablePlugins(JavaAppPackaging)
maintainer := "[email protected]"

dockerBaseImage := "java:14"

lexi-lambda

Monads and delimited control are very closely related, so it isn’t too hard to understand them in terms of one another. From a monadic point of view, the big idea is that if you have the computation m >>= f, then f is m’s continuation. It’s the function that is called with m’s result to continue execution after m returns.

If you have a long chain of binds, the continuation is just the composition of all of them. So, for example, if you have

m >>= f >>= g >>= h

then the continuation of m is f >=> g >=> h. Likewise, the continuation of m >>= f is g >=> h.

chrisdone

Statically checked overloaded strings

This gist demonstrates a trick I came up with which is defining IsString for Q (TExp a), where a is lift-able. This allows you to write $$("...") and have the string parsed at compile-time.

On GHC 9, you are able to write $$"..." instead.

This offers a light-weight way to enforce compile-time constraints. It's basically OverloadedStrings with static checks. The inferred return type

emcake

type ListBuilder() =
    
    /// map
    member x.For(l,f) = 
        List.map f l

    /// id
    member x.Yield(v) = 
        v

Althorion

;; The next line may not be needed
(set-default-font  "Source Code Pro for Powerline 13")

;; Fira code
;; This works when using emacs --daemon + emacsclient
(add-hook 'after-make-frame-functions (lambda (frame) (set-fontset-font t '(#Xe100 . #Xe16f) "Fira Code Symbol")))
;; This works when using emacs without server/client
(set-fontset-font t '(#Xe100 . #Xe16f) "Fira Code Symbol")
;; I haven't found one statement that makes both of the above situations work, so I use both for now