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package i94
import scala.language.higherKinds
trait Base {
type Rep[T]
}
trait BaseExp extends Base {
type Rep[T] = Exp[T]
case class Exp[T](v: T)
}
trait BaseStr extends Base {
type Rep[T] = String
}
trait BaseDirect extends Base {
type Rep[T] = T
}
trait Test1 {
trait Monad[X] {
def x: X
}
sealed abstract class Either[A,B]
case class Left[A,B](x: A) extends Either[A,B] with Monad[A]
case class Right[A,B](x: B) extends Either[A,B] with Monad[B]
def flatMap[X,Y,M[X]<:Monad[X]](m: M[X], f: X => M[Y]): M[Y] = f(m.x)
println(flatMap(Left(1), {x: Int => Left(x)}))
}
trait Test2 {
trait Monad[X] {
def x: X
}
sealed abstract class Either[A,B]
case class Left[A,B](x: A) extends Either[A,B] with Monad[A]
case class Right[A,B](x: B) extends Either[A,B] with Monad[B]
def flatMap[X,Y,M[X]](m: M[X], f: X => M[Y]): M[Y]
println(flatMap(Left(1), {x: Int => Left(x)}))
}
trait Test3 {
def flatMap[X,Y,M[X]](m: M[X], f: X => M[Y]): M[Y]
println(flatMap(Some(1), {x: Int => Some(x)}))
}
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