Daniel Westheide dwestheide

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You might also be interested in the 2016 version.

Applied Functional Programming with Scala - Notes

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

Easy Scala Publication

The following describes how you can publish artifacts for any sbt project using the GitHub Package Registry and the sbt-github-packages plugin.

Step 1: Create a GitHub Token

In your GitHub account, go to Settings > Developer settings > Personal access tokens, then click on Generate new token (or click here). Fill in some sort of meaningful name (I chose Dev) and click on the write:packages checkbox:

	$stack, $draws = [], {}

	def method_missing *args
	return if args[0][/^to_/]
	$stack << args.map { \|a\| a or $stack.pop }
	$draws[$stack.pop(2)[0][0]] = args[1] if args[0] == :<
	end

	class Array
	def +@

	object NettyFutureBridge {
	import scala.concurrent.{ Promise, Future }
	import scala.util.Try
	import java.util.concurrent.CancellationException
	import org.jboss.netty.channel.{ Channel, ChannelFuture, ChannelFutureListener }

	def apply(nettyFuture: ChannelFuture): Future[Channel] = {
	val p = Promise[Channel]()
	nettyFuture.addListener(new ChannelFutureListener {
	def operationComplete(future: ChannelFuture): Unit = p complete Try(

	class MyManagedResource extends ResourceController[String] {
	def index = Action(Ok("index"))

	def newScreen = Action(Ok("new"))

	def create = Action {
	Redirect(MyInjectableResource.reverseRoutes.index())
	}

	def show(id: String) = Action(Ok("Show " + id))

	/**
	* Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
	*/
	package akka.contrib.mailbox

	import scala.concurrent.duration._
	import java.util.concurrent.atomic.AtomicInteger
	import java.util.concurrent.atomic.AtomicLong
	import com.typesafe.config.Config
	import akka.actor.{ ActorContext, ActorRef, ActorSystem, ExtendedActorSystem }

	/**
	* The MIT License (MIT)
	*
	* Copyright (c) 2013-2015 Andrew Snare, Age Mooij
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is

	// Inspired by a tweet from @trautonen 1/13/2016
	// Use Source.unfoldAsync to turn paginated database results into an akka-streams Source
	// unfold is the inverse of fold

	case class Page[T](pageNumber:Long, totalPages:Long, contents:List[T])
	case class Thing(id: Long, name: String = "foo")

	val totalPages = 5 //
	val pageSize = 3