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{"lastUpload":"2020-10-16T15:12:58.640Z","extensionVersion":"v3.4.3"}

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import java.io.{ByteArrayOutputStream, ByteArrayInputStream}
import java.util.zip.{GZIPOutputStream, GZIPInputStream}

import scala.util.Try

object Gzip {

  def compress(input: Array[Byte]): Array[Byte] = {
    val bos = new ByteArrayOutputStream(input.length)
    val gzip = new GZIPOutputStream(bos)

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loadNumberOfItems("foo.bar") shouldBe a [Int]
// InvalidUrlException
loadNumberOfItems("http://google.com") shouldBe a [Int]
// InvalidPayloadException
loadNumberOfItems("http://actual.server.endpoint.com/number") shouldBe a [Int]
// ParsingException
loadNumberOfItems("http://actual.server.endpoint.com/number") shouldBe a [Int]
// ClassCastException

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sealed trait Exception
case object InvalidUrl extends Exception
case object InvalidJson extends Exception

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def loadNumberOfItems(url: String): Int = {
  val json: Json = request(url)
  json.getField("number").asInstanceOf[Int]
}

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def loadNumberOfItems(url: String): IO[Either[Exception, Int]] =
  Url(url)
  .toRight(InvalidUrl)
  .map(request(_))
  .traverse(_.map(_.getFieldOption("number").flatMap(_.as[Int]).toRight(InvalidJson)))
  .map(_.flatten)

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def loadNumberOfItems(url: String): IO[Either[Exception, Int]] = {
  val maybeUrl: Option[Url] =
    Url(url)
  val eitherUrl: Either[Exception, Url] =
    maybeUrl.toRight(InvalidUrl)
  val eitherJson: Either[Exception, IO[Json]] =
    eitherUrl.map(u => request(u))
  val eitherResult: Either[Exception, IO[Either[Exception, Int]]] =
    eitherJson.map(futureJson =>
      futureJson.map(json => json.getFieldOption("number").flatMap(x => x.as[Int]).toRight(InvalidJson)))

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def count(p: A => Boolean): Int

def find(p: A => Boolean): Option[A]

def filter(p: A => Boolean): List[A]

def exists(p: A => Boolean): Boolean

def forall(p: A => Boolean): Boolean

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Cafe.buyCoffee(creditCard) shouldBe (coffee, charge)

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object Cafe {
  def buyCoffee(creditCard: CreditCard): (Coffee, Charge) = {
    val cup = new Coffee()                // new coffee is created
    (cup, Charge(creditCart, cup.price))  // cup and charge is returned
  }
}
// Can be created without new keyword
case class Charge(creditCard: CreditCard, amount: Double)