mandubian

import play.api.libs.json._
import play.api.libs.functional.syntax._
 
sealed trait Shape

case class Circle(c: (Float, Float), r: Float) extends Shape
object Circle {
  // reader is covariant and can be implicit in inheriting caseclasses
  implicit val reader = Json.reads[Circle]
  // writer is contravariant and can't be implicit in inheriting caseclasses

guillaumebort

package controllers;

import play.*;
import play.mvc.*;

import views.html.*;

public class Application extends Controller {

    public static Result index(String name) {