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import scala.language.existentials
import scala.language.reflectiveCalls
class Foo {
class Line {
case class Cell[T](var x: T)
def f[T](x: Any): Cell[t1] forSome { type t1 } = x match { case y: Cell[t] => y }
var x: Cell[T] forSome { type T } = new Cell(1)
println({ x = new Cell("abc"); x })
}
}
class FooW {
class Line {
case class Cell[T](var x: T)
def f[T](x: Any): Cell[ _ ] = x match { case y: Cell[t] => y }
var x: Cell[_] = new Cell(1)
println({ x = new Cell("abc"); x })
}
}
trait Counter[T] {
def newCounter: T
def get(i: T): Int
def inc(i: T): T
}
case class C[T](x: T)
object LUB {
def x = C(1)
def y = C("abc")
var coinflip: Boolean = _
def z = if (coinflip) x else y
def zz: C[_1] forSome { type _1 >: Int with java.lang.String } = z
def zzs: C[_ >: Int with java.lang.String] = z
}
object Bug1189 {
case class Cell[T](x: T)
type U = Cell[T1] forSome { type T1 }
def f(x: Any): U = x match { case y: Cell[_] => y }
var x: U = Cell(1)
println(x)
println(f(x))
x = Cell("abc")
println(x)
println(f(x))
}
object Test extends App {
val x = { class I; class J; (new C(new I), new C(new J)) }
val y: (C[X], C[Y]) forSome { type X; type Y } = x
def foo(x : Counter[T] { def name : String } forSome { type T }) = x match {
case ctr: Counter[t] =>
val c = ctr.newCounter
println(ctr.name+" "+ctr.get(ctr.inc(ctr.inc(c))))
case _ =>
}
def fooW(x : Counter[T] { def name : String } forSome { type T }) = x match {
case ctr: Counter[t] =>
val c = ctr.newCounter
println(ctr.name+" "+ctr.get(ctr.inc(ctr.inc(c))))
case _ =>
}
val ci = new Counter[Int] {
def newCounter = 0
def get(i: Int) = i
def inc(i: Int) = i+1
def name = "Int"
}
val cf = new Counter[Float] {
def newCounter = 0
def get(i: Float) = i.intValue
def inc(i: Float) = i+1
def name = "Float"
}
var ex: Counter[T] forSome { type T } = _
ex = ci
ex = cf
var exW: Counter[_] = _
ex = ci
ex = cf
foo(ci)
foo(cf)
fooW(ci)
fooW(cf)
val foo = new Foo
new foo.Line
val fooW = new FooW
new fooW.Line
}
trait FooBar[ A <: Option[_]] { def foo: A }
trait SubFooBar[B <: Option[_]] extends FooBar[B]
object Test1 {
var pc: List[Product with (Counter[T] forSome { type T })] = List()
def f() = pc
pc = f()
}
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