mpkocher

//> using platform "jvm"
//> using scala "2.13.8"
//> using lib "dev.zio::zio:1.0.14"
//> using lib "com.monovore::decline:2.2.0"
//> using mainClass "DeclinedApp"

// Runnable using `scala-cli run Declined.scala  -- --user Ralph --alpha 3.14`

import zio.{ExitCode, ZEnv, ZIO, Task, RIO, IO, UIO, URIO}
import zio.console._

quelgar

Every Argument for Static Typing Applies to Typed Errors

Think of all the arguments you've heard as to why static typing is desirable — every single one of those arguments applies equally well to using types to represent error conditions.

An odd thing I’ve observed about the Scala community is how many of its members believe that a) a language with a sophisticated static type system is very valuable; and b) that using types for error handling is basically a waste of time. If static types are useful—and if you like Scala, presumably you think they are—then using them to represent error conditions is also useful.

Here's a little secret of functional programming: errors aren't some special thing that operate under a different set of rules to everything else. Yes, there are a set of common patterns we group under the loose heading "error handling", but fundamentally we're just dealing with more values. Values that can have types associated with them. There's absolutely no reason why the benefits of static ty

djspiewak

Fibers

Fibers are an abstraction over sequential computation, similar to threads but at a higher level. There are two ways to think about this model: by example, and abstractly from first principles. We'll start with the example.

(credit here is very much due to Fabio Labella, who's incredible Scala World talk describes these ideas far better than I can)

Callback Sequentialization

Consider the following three functions

MateuszKubuszok

Useful Ammonite snippets

All of these can be figured out by looking at ammonite.io and at libraries pages, but to make things faster for myself I written it down (I don't always want to search through Ammonite history nor pollute my ~/.ammonite/predef.sc).

For convenience, next to library there is badge with the newest version and next to one liners for Ammonite for specific version is link to releases - it let you update to newest version without goolging or checking project's site.

• Ammonite for specific Scala version
  • 2.10
  • 2.11
• 2.12

yogthos

Introductory resources

• High level overview https://yogthos.github.io/ClojureDistilled.html
• An Animated Introduction to Clojure https://markm208.github.io/cljbook/
• Interactive tutorial in a browser https://tryclojure.org/
• Interactive exercises http://clojurescriptkoans.com/
• Clerk notebooks with introductory examples https://github.clerk.garden/anthonygalea/notes-on-clojure
• More interactive exercises https://4clojure.oxal.org/
• Lambda Island tutorials https://lambdaisland.com/
• Functional Programming with Clojure resources https://practicalli.github.io/

hilios

import scala.concurrent.{Await, ExecutionContext, Future, Promise}
import cats.implicits._

import scala.concurrent.duration.Duration
import scala.util.{Failure, Success}

final case class FutureConcurrentEffect()(implicit ec: ExecutionContext) extends FutureEffect with ConcurrentEffect[Future] {
  def start[A](fa: Future[A]): Future[Fiber[Future, A]] = Future.successful {
    FutureFiber(fa)
  }

neko-kai

package quantified

import cats.Monad

import scala.language.implicitConversions

/**
  * C[_] constraint applied to type F[_, _] quantified in first parameter, i.e.
  *
  * {{{

jdegoes

package fpmax

import scala.util.Try
import scala.io.StdIn.readLine

object App0 {
  def main: Unit = {
    println("What is your name?")

    val name = readLine()

wogan

package retry

import scala.concurrent.duration.{Duration, FiniteDuration}
import scala.util.Random

import scala.concurrent.duration._

object Backoff {

  val none: Backoff = _ => Duration.Zero

timothyklim

package utils

import akka.stream._
import akka.stream.scaladsl._
import akka.stream.stage._
import akka.util.{ByteString, ByteStringBuilder}
import scala.annotation.tailrec
import java.security.SecureRandom
import java.security.{Key, KeyFactory, PublicKey, PrivateKey}
import java.security.spec.{PKCS8EncodedKeySpec, X509EncodedKeySpec}