dacr

David's programming examples knowledge base

• Generated by code-examples-manager release 2.4.5-SNAPSHOT
• 561 published examples

akka-pekko

• akka-actors-hello-world.sc : Simple akka hello world example
• akka-capitalize-and-print.sc : dump capitalized string coming from stdin using streams
• akka-http-client-json-stream.sc : Fully asynchronous http client call with json streamed response using akka-http will work in all cases, even with chunked responses !
• akka-http-client-json-with-proxy.sc : Fully asynchronous http client call with json response using akka-http will work in all cases, even with chunked responses, this example add automatic http proxy support.
• [akka-http-client-json.sc](https:/

seoh

notxcain

import cats.data.Kleisli
import cats.effect.{ Concurrent, Sync }
import cats.effect.concurrent.MVar
import cats.implicits._
import cats.{ Applicative, Functor, Monad }

// Let's start with our dsl

// First we need to interact with a console
trait Console[F[_]] {

seratch

import org.scalatest._

class H2Spec extends FlatSpec with Matchers {

  case class Sample(id: Long, name: Option[String])

  "H2 connections" should "work" in {

    import io.r2dbc.h2.{ H2ConnectionConfiguration, H2ConnectionFactory }
    import io.r2dbc.client.R2dbc

e8kor

// Snippet
import akka.event.LogMarker
import akka.event.slf4j.Slf4jLogMarker
import net.logstash.logback.marker.RawJsonAppendingMarker

import io.circe._
import io.circe.generic.extras._
import io.circe.syntax._

implicit private val config: Configuration = Configuration.default.withSnakeCaseMemberNames // ELK has good support for snake case json convention

kryptt

package br
package blocks

import scala.concurrent.{ExecutionContext, Future}

import fs2.{Strategy, Stream, Task}
import fs2.async.mutable.Topic

abstract class Piece[Model, View]
  (events: Stream[Task, Any])(implicit ec: ExecutionContext) {

notxcain

import cats.data.{ EitherT, State }
import cats.implicits._
import cats.{ Monad, ~> }
import io.aecor.liberator.macros.free
import io.aecor.liberator.syntax._
import io.aecor.liberator.{ ProductKK, Term }

@free
trait Api[F[_]] {
  def doThing(aThing: String, params: Map[String, String]): F[Either[String, String]]

OlivierBlanvillain

Revisiting Tagless Final Interpreters

Tageless Final interpreters are an alternative to the traditional Algebraic Data Type (and generalized ADT) based implementation of the interpreter pattern. This document presents the Tageless Final approach with Scala, and shows how Dotty with it's recently added implicits functions makes the approach even more appealing. All examples are direct translations of their Haskell version presented in the Typed Tagless Final Interpreters: Lecture Notes (section 2).

The interpreter pattern has recently received a lot of attention in the Scala community. A lot of efforts have been invested in trying to address the biggest shortcomings of ADT/GADT based solutions: extensibility. One can first look at cats' Inject typeclass for an implementation of [Data Type à la Carte](http://www.cs.ru.nl/~W.Swierstra/Publications/DataTypesA

bmc

object StaticFile {

  // Various necessary imports. Notes:
  //
  // 1. fs2 is necessary. See https://github.com/functional-streams-for-scala/fs2
  // 2. streamz is necessary. See https://github.com/krasserm/streamz
  // 3. Apache Tika is used to infer MIME types from file names, because it's more reliable and
  //    fully-featured than using java.nio.file.Files.probeContentType().
  //
  // If using SBT, you'll want these library dependencies and resolvers:

djspiewak

Getting Started in Scala

This is my attempt to give Scala newcomers a quick-and-easy rundown to the prerequisite steps they need to a) try Scala, and b) get a standard project up and running on their machine. I'm not going to talk about the language at all; there are plenty of better resources a google search away. This is just focused on the prerequisite tooling and machine setup. I will not be assuming you have any background in JVM languages. So if you're coming from Python, Ruby, JavaScript, Haskell, or anywhere…  I hope to present the information you need without assuming anything.

Disclaimer It has been over a decade since I was new to Scala, and when I was new to Scala, I was coming from a Java and Ruby background. This has probably caused me to unknowingly make some assumptions. Please feel free to call me out in comments/tweets!

One assumption I'm knowingly making is that you're on a Unix-like platform. Sorry, Windows users.

Getting the JVM