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package magnolia.examples
import magnolia._
import language.experimental.macros
import language.higherKinds
import collection.immutable.ListMap
object `package` {
implicit class Showable[T: Show](t: T) {
def show: String = implicitly[Show[T]].show(t)
}
implicit val showString: Show[String] = identity
implicit val showBool: Show[Boolean] = _.toString
implicit def showList[T: Show]: Show[List[T]] = xs => xs.map { x => s"list:${implicitly[Show[T]].show(x)}" }.mkString(";")
implicit def showSet[T: Show]: Show[Set[T]] = s => "set"
implicit class Equable[T: Eq](t: T) {
def isEqualTo(other: T): Boolean = implicitly[Eq[T]].isEqual(t, other)
}
implicit val eqString: Eq[String] = _ == _
implicit val eqBool: Eq[Boolean] = _ == _
implicit def eqList[T: Eq]: Eq[List[T]] =
(l1, l2) => l1.size == l2.size && (l1 zip l2).forall { case (e1, e2) => e1 isEqualTo e2 }
implicit def eqSet[T: Eq]: Eq[Set[T]] =
(s1, s2) => s1.size == s2.size && (s1 zip s2).forall { case (e1, e2) => e1 isEqualTo e2 }
}
sealed trait Tree
case class Branch(left: Tree, right: Tree) extends Tree
case class Leaf(value: Int) extends Tree
sealed trait Entity
case class Person(name: String, address: Address) extends Entity
case class Organization(name: String, contacts: Set[Person]) extends Entity
case class Address(lines: List[String], country: Country)
case class Country(name: String, code: String, salesTax: Boolean)
trait Show[T] { def show(t: T): String }
object Show extends Show_1 {
implicit val showInt: Show[Int] = _.toString
implicit val derivation = new ContravariantDerivation[Show] {
type Return = String
def call[T](show: Show[T], value: T): String = show.show(value)
def construct[T](body: T => String): Show[T] = body(_)
def join(xs: ListMap[String, String]): String = xs.map { case (k, v) => s"$k=$v" }.mkString("{", ", ", "}")
}
}
trait Show_1 {
implicit def generic[T]: Show[T] = macro Macros.magnolia[T, Show[_]]
}
trait Eq[T] { def isEqual(a: T, b: T): Boolean }
object Eq extends Eq_1 {
implicit val eqInt: Eq[Int] = _ == _
implicit val derivation = new ContravariantDerivation2[Eq] {
type Return = Boolean
def call[T](eq: Eq[T], value1: T, value2: T): Boolean =
if(value1.getClass == value2.getClass) eq.isEqual(value1, value2) else false
def construct[T](body: (T, T) => Boolean): Eq[T] = body(_, _)
def join(elements: ListMap[String, Boolean]): Boolean = elements.forall(_._2)
}
}
trait Eq_1 {
implicit def generic[T]: Eq[T] = macro Macros.magnolia[T, Eq[_]]
}
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