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import scala.language.reflectiveCalls
class Coll[+T] {
type A1 <: T
type A2 <: A1
def contains = new { def apply[T1 <: T](value: T1) = ??? }
def contains1 = new { def apply[T1 <: A1](value: T1) = ??? }
def contains2 = new { def apply[T1 <: A2](value: T1) = ??? }
def contains3 = {
trait Bippy {
type B1 <: T
type B2 <: B1
}
new Bippy { def apply[T1 <: T](value: T1) = ??? }
new Bippy { def apply[T1 <: B1](value: T1) = ??? }
new Bippy { def apply[T1 <: B2](value: T1) = ??? }
new Bippy {
type B3 = B2
type B4 = List[B2]
def apply1[T1 <: B3](value: T1) = ???
def apply2[T1 <: B4](value: T1) = ???
def apply3(value: B3) = ???
def apply4(value: B4) = value.head
}
}
def contains4 = new {
def apply1(s: String)(x: Int)(value: T) = ???
def apply2[T1 <: T](s: String)(x: Int)(value: T1) = ???
}
def containsOk = {
trait Bippy {
type B1 <: AnyRef
type B2 <: B1
}
new Bippy { def apply[T1 <: AnyRef](value: T1) = ??? }
new Bippy { type B1 = String ; def apply[T1 <: B1](value: T1) = ??? }
new Bippy { type B2 = String ; def apply[T1 <: B2](value: T1) = ??? }
}
}
object Test {
def main(args: Array[String]): Unit = {
val xs = new Coll[List[String]]
val ys: Coll[Traversable[String]] = xs
println(ys contains Nil)
// java.lang.NoSuchMethodException: Coll$$anon$1.apply(scala.collection.Traversable)
// at java.lang.Class.getMethod(Class.java:1605)
// at Test$.reflMethod$Method1(a.scala:14)
// at Test$.main(a.scala:14)
// at Test.main(a.scala)
}
}
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