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// /scala/trac/5777/a.scala
// Wed May 9 08:44:57 PDT 2012
trait Ring {
trait E
}
class Poly[C <: Ring](val ring: C) extends Ring
// This definition of Poly triggers the same failure on *both* versions
// class Poly(val ring: Ring) extends Ring
object BigInt extends Ring
object MyApp {
val r = new Poly(BigInt)
implicitly[r.ring.E <:< BigInt.E]
// fail on 2.10, works on 2.9.2
(null.asInstanceOf[BigInt.E] : r.ring.E)
// works on both versions
val r1 = new Poly[BigInt.type](BigInt)
(null.asInstanceOf[BigInt.E] : r1.ring.E)
// Oddly, -Xprint:typer reports that r and r1 have the same inferred type.
//
// private[this] val r: Poly[BigInt.type] = new Poly[BigInt.type](BigInt);
// <stable> <accessor> def r: Poly[BigInt.type] = MyApp.this.r;
// (null.asInstanceOf[BigInt.E]: MyApp.r.ring.E);
// private[this] val r1: Poly[BigInt.type] = new Poly[BigInt.type](BigInt);
// <stable> <accessor> def r1: Poly[BigInt.type] = MyApp.this.r1;
// (null.asInstanceOf[BigInt.E]: MyApp.r1.ring.E)
// diff typer-2.9.2.txt typer-2.10.txt
// ...
// ---
// > object MyApp extends scala.AnyRef {
// > def <init>(): MyApp.type = {
// > MyApp.super.<init>();
// 30c30
// < scala.this.Predef.implicitly[<:<[BigInt.E,MyApp.r.ring.E]](scala.this.Predef.conforms[BigInt.E]);
// ---
// > scala.this.Predef.implicitly[<:<[BigInt.E,MyApp.r.ring.E]]();
}
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