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// Tue Jul 12 16:38:23 PDT 2011
class Bip[T1]
class Foo[T2] extends Bip[T2]
class Bar[T3] extends Bip[T3]
abstract class Factory[CC[X] <: Bip[X]] { }
object Quux1 extends Factory[Foo]
object Quux2 extends Factory[Bar]
object Test {
// FAIL
val xs = List(Quux1, Quux2)
// error: type mismatch;
// found : Quux1.type (with underlying type object Quux1)
// required: Factory[_ >: Bar with Foo <: Bip]
// ^^ ^^ ^^ ^^ <-- QUIZ: what is missing from these types?
// The type it should figure out, come on scalac
type F = Factory[CC] forSome { type X ; type CC[X] >: Bar[X] with Foo[X] <: Bip[X] }
// No problem
val ys = List[F](Quux1, Quux2)
// A repl session to get you started.
/*
val quux1 = EmptyPackageClass.tpe.member(TermName("Quux1"))
val quux2 = EmptyPackageClass.tpe.member(TermName("Quux2"))
val tps = List(quux1, quux2) map (_.tpe)
val test = EmptyPackageClass.tpe.member(TermName("Test"))
val f = test.tpe.member(TypeName("F")).tpe
val fn = f.normalize.asInstanceOf[ExistentialType]
val fn2 = fn.underlying.asInstanceOf[TypeRef]
*/
}
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