polyglotpiglet

public static void main(String... args) {

    int count = 0;
    for (int i = 0; i<100000; i++) {
        count += doubleMe(2);
        count += doubleMe(4);
    }
    System.out.println(count);
}

polyglotpiglet

public static void main(String... args) {

    int count = 0;
    for (int i = 0; i<100000; i++) {
        count += wrapper();
    }
    System.out.println(count);
}

private static int wrapper() {

polyglotpiglet

for {
  p <- people
  if p.age < 30 && p.age >= 20
} yield p.name

polyglotpiglet

SELECT name FROM people WHERE age < 30 AND age >= 20

polyglotpiglet

people.withFilter(p => p.age < 30 && p.age >= 20).map(p => p.name)

polyglotpiglet

import scala.util.Random

object MonthHall extends App {

  val numberOfIterations = 1000000

  val numberOfWins = (0 until numberOfIterations).count(_ => {
    val winningDoor = Random.nextInt(3)
    val chosenDoor = Random.nextInt(3)

polyglotpiglet

import java.util.Random;
import java.util.concurrent.*;

class NoVisibility {

    private boolean ready;
    private int number;
    private final ExecutorService executor;
    private final Random random;

polyglotpiglet

import org.junit.Test;

import java.util.Random;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import static org.assertj.core.api.Assertions.assertThat;

public class NoVisibilityTest {

polyglotpiglet

sealed trait InMyPocket[-A]

sealed trait Cuddler
final case class Puppy(name: String) extends Cuddler

object VarianceExample {

  var dog: InMyPocket[Puppy] = new InMyPocket[Puppy] {}
  var cuddler: InMyPocket[Cuddler] = new InMyPocket[Cuddler] {}

polyglotpiglet

sealed trait InMyPocket[-A]

sealed trait Cuddler
final case class Puppy(name: String) extends Cuddler

object VarianceExample {

  var dog: InMyPocket[Puppy] = new InMyPocket[Puppy] {}
  var cuddler: InMyPocket[Cuddler] = new InMyPocket[Cuddler] {}