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// a.scala
// Thu Sep 27 09:42:16 PDT 2012
trait Bar[-T1, T2, +T3] { }
trait Foo[-T1, T2, +T3] extends Bar[T1, T2, T3]
class A {
var b = true
def f1(x: Foo[Int, Int, Int]) = x match {
/* nowarn */ case _: Foo[Nothing, Int, Any] => true
}
def f2[T, U, V](x: Foo[T, U, V]) = x match {
/* nowarn */ case _: Foo[Nothing, U, Any] => true
}
def f3[T, U, V](x: Foo[T, U, V]) = x match {
/* warn */ case _: Foo[U, U, V] if b => ()
/* nowarn */ case _: Foo[Nothing, U, V] if b => ()
/* warn */ case _: Foo[Any, U, V] if b => ()
}
def f4(xs: List[Int]) = xs match {
/* nowarn - todo */ case x: AnyRef { def bippy: Int } if b => x.bippy // this could/should do an instance check and not warn
/* nowarn - todo */ case x: AnyRef { def size: Int } if b => x.size // this could/should do a static conformance test and not warn
/* nowarn */ case x: ((AnyRef { def size: Int }) @unchecked) if b => x.size
}
}
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