lbialy’s gists

lbialy / no-illegal-states.scala

Created November 2, 2024 10:45

Making illegal states unrepresentable the Scala way

	//> using scala 3.5.2
	//> using dep "com.softwaremill.ox::core:0.5.2"

	object types:
	opaque type Title = String
	object Title:
	def apply(title: String): Either[Exception, Title] =
	if title.isBlank then Left(Exception("Title must not be blank"))
	else Right(title)

lbialy / kyo-discipline.scala

Created October 19, 2024 19:37

Kyo passes monadic laws via Discipline

	//> using scala 3.5.1

	//> using test.dep org.typelevel::cats-laws:2.12.0
	//> using test.dep org.typelevel::discipline-munit:2.0.0

	//> using test.dep io.getkyo::kyo-core:0.13.1
	//> using test.dep io.getkyo::kyo-cats:0.13.1

	//> using test.dep org.scalameta::munit:1.0.2

lbialy / graalvm-in-docker.txt

Created March 28, 2024 21:30

Have fun Anton

	$ sbt new http4s/http4s.g8 --branch 1.0-scala3
	// use all the defaults, just set sbt to 1.9.9

	$ cd quickstart

	$ sbt assembly

	$ cat Dockerfile # create this file with these contents:
	FROM ghcr.io/graalvm/jdk-community:22
	RUN mkdir /opt/app

lbialy / async-exfiltration-prevention.scala

Created March 26, 2024 17:23

	//> using scala 3.4.0

	import language.experimental.captureChecking

	class DbCon:
	def runUpdate(): Unit = println(s"runUpdate on ${Thread.currentThread()}")
	def close(): Unit = println("closing DbCon")

	def transact[A](f: DbCon^ => A): A =
	val dbCon = DbCon()

lbialy / backpressure.scala

Created March 2, 2024 22:10

Demonstration of backpressure with Loom

	//> using scala 3.3.3
	//> using jvm graalvm-java21:21.0.2
	//> using dep com.softwaremill.ox::core:0.0.21

	import ox.*
	import java.util.concurrent.*

	@main def main = supervised {
	val queue = ArrayBlockingQueue[Int](5)

lbialy / Helpers.scala

Last active February 27, 2024 17:19 — forked from prolativ/Helpers.scala

	import scala.quoted.*

	extension (using quotes: Quotes)(repr: quotes.reflect.TypeRepr)
	def flatMapResultType(f: quotes.reflect.TypeRepr => Option[quotes.reflect.TypeRepr]): Option[quotes.reflect.TypeRepr] =
	import quotes.reflect.*
	repr match
	case MethodType(paramNames, paramTypes, resultType) =>
	resultType.flatMapResultType(f).map(tp => MethodType(paramNames)(_ => paramTypes, _ => tp))
	// case PolyType => // should not appear here
	case tp =>

lbialy / caliban-demo.sc

Last active December 30, 2023 13:04

Run with `scala-cli run caliban-demo.sc` or `scala-cli run https://gist.github.com/lbialy/c9aa46136f3ee7897600c697de273567`

	//> using dep com.github.ghostdogpr::caliban-quick:2.5.0

	enum Origin {
	case EARTH, MARS, BELT
	}

	case class Character(
	name: String,
	nicknames: List[String],
	origin: Origin

lbialy / main.scala

Last active December 29, 2023 21:09

comparing word counting: std vs fs2

	//> using scala "3.3.1"
	//> using lib "co.fs2::fs2-io:3.9.3"

	import scala.util.*
	import scala.io.Source

	def safePrintln(s: Any): Either[Throwable, Unit] =
	try Right(println(s))
	catch case err: Throwable => Left(err)

lbialy / app.decompiled.java

Created October 27, 2023 12:24

Decompiled Kotlin coroutine rendezvous from SML Blogpost

	// AppKt.java
	package hello;

	import kotlin.Metadata;
	import kotlin.coroutines.Continuation;
	import kotlin.coroutines.CoroutineContext;
	import kotlin.jvm.functions.Function0;
	import kotlin.jvm.functions.Function2;
	import kotlin.jvm.internal.Intrinsics;
	import kotlin.jvm.internal.SourceDebugExtension;

lbialy / pom.xml

Created October 27, 2023 11:10

Pom for kotlin coroutines rendezvous snippet

	<?xml version="1.0" encoding="UTF-8"?>
	<project
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
	xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

	<modelVersion>4.0.0</modelVersion>

	<groupId>org.jetbrains.kotlin.examples</groupId>
	<artifactId>hello-world</artifactId>
	<version>1.0-SNAPSHOT</version>

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