kubukoz

#!/bin/bash

set -euo pipefail

# You'll have to change this, also see note about caveat below
SDK_PATH=/Users/kubukoz/Developer/PlaydateSDK/C_API

rm -rf HelloWorld.pdx || true
rm Source/pdex.elf || true

kubukoz

Jakub Kozłowski | Scala in the city | 26 X 2023

Code | Recording

---

Why build an IDE?

1. For fun
2. For your proprietary DSL

kubukoz

// compiles
//> using scala "3.3.1"
import scala.annotation.tailrec

case class Opt[A](value: A | Null) {

  inline def flatMap[B](inline f: A => Opt[B]): Opt[B] =
    if (value == null)
      Opt(null)
    else

kubukoz

You mention that you would only use circe auto derivation in only a few limited cases - may I ask why? It looks like you are using semi-auto derivation instead. Why is this better/more stable?

The difference is where the derivation happens - in semiauto, you only have one place where a codec for a given type will be derived: at definition site, which is usually the companion object (it's the companion object in our case, but it could be anywhere really - point still stands that it's easier to track). In auto derivation, codecs are derived as needed by the usage - e.g. in the endpoint definitions or in a controller (depending on the tech stack you use). The problem here is that you need all the codecs of all the fields and all their fields (...and so on...) to be available there.

The centralization of the codecs in Semiauto mode allows us to switch to a different format at any time, while keeping the representation consistent across all usages of it. Additionally, it allows us to test the codec logic witho

kubukoz

def showProcessedCount[F[_]: Concurrent: Timer, A]: Pipe[F, A, A] = stream =>
  fs2.Stream.eval(Ref[F].of(0)).flatMap { count =>
    stream.chunks
      .evalMap { chunk =>
        count.update(_ + chunk.size).as(chunk)
      }
      .flatMap(fs2.Stream.chunk)
      .concurrently(
        fs2.Stream

kubukoz

//> using scala "3.2.2"
//> using lib "co.fs2::fs2-io:3.6.1"
//> using lib "io.circe::circe-core:0.14.5"
//> using lib "io.circe::circe-parser:0.14.5"
import cats.data.NonEmptyList
import cats.effect.IO
import cats.effect.IOApp
import cats.implicits.*
import cats.kernel.Order
import fs2.io.file.Files

kubukoz

//> using lib "co.fs2::fs2-core:3.7.0-RC4"
import cats.effect.IOApp
import cats.effect.IO
import scala.concurrent.duration._
import cats.effect.std.UUIDGen
import cats.implicits._
import scala.util.Random
import fs2.concurrent.Signal

object Demo extends IOApp.Simple {

kubukoz

//> using scala "2.13.10"
//> using lib "co.fs2::fs2-io:3.5.0"
//> using option "-Wunused:imports"
import cats.effect.IO
import cats.effect.IOApp
import cats.effect.kernel.Resource
import cats.implicits._
import fs2.io.file.Files
import fs2.io.file.Path

kubukoz

https://www.usenix.org/legacy/events/hotos07/tech/full_papers/dolstra/dolstra.pdf
https://edolstra.github.io/pubs/phd-thesis.pdf
https://nixos.org/manual/nix/stable/
https://nixos.org/guides/nix-pills/index.html
https://nix.dev/
https://wiki.nikitavoloboev.xyz/package-managers/nix
https://edolstra.github.io/pubs/nixos-jfp-final.pdf
https://nixos.org/docs/SCR-2005-091.pdf
https://medium.com/@MrJamesFisher/nix-by-example-a0063a1a4c55
https://scrive.github.io/nix-workshop/01-getting-started/01-introduction.html

kubukoz

//> using lib "software.amazon.smithy:smithy-model:1.26.4"
//> using scala "2.13.10"
import software.amazon.smithy.model.Model
import software.amazon.smithy.model.neighbor.NeighborProvider
import software.amazon.smithy.model.shapes.ShapeId

import scala.jdk.CollectionConverters._

object demo extends App {