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-rw-r--r--test/files/pos/depmet_implicit_norm_ret.scala29
1 files changed, 29 insertions, 0 deletions
diff --git a/test/files/pos/depmet_implicit_norm_ret.scala b/test/files/pos/depmet_implicit_norm_ret.scala
new file mode 100644
index 0000000000..4cdb2931c6
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+++ b/test/files/pos/depmet_implicit_norm_ret.scala
@@ -0,0 +1,29 @@
+object Test{
+ def ?[S <: AnyRef](implicit w : S) : w.type = w
+
+ // fallback, lower priority (overloading rules apply: pick alternative in subclass lowest in subtyping lattice)
+ class ZipWithDefault {
+ implicit def ZeroZipWith[S] = new ZipWith[S] {
+ type T = Stream[S]
+ }
+ }
+
+ object ZipWith extends ZipWithDefault {
+ // def apply[S: ZipWith](s : S) = ?[ZipWith[S]].zipWith(s) // TODO: bug return type should be inferred
+ def apply[S](s : S)(implicit zw: ZipWith[S]): zw.T = zw.zipWith(s)
+
+ implicit def SuccZipWith[S,R](implicit zWith : ZipWith[R]) = new ZipWith[S => R] {
+ type T = Stream[S] => zWith.T // dependent types replace the associated types functionality
+ }
+ }
+
+ trait ZipWith[S] {
+ type T
+ def zipWith : S => T = error("")
+ }
+
+ // bug: inferred return type = (Stream[A]) => java.lang.Object with Test.ZipWith[B]{type T = Stream[B]}#T
+ // this seems incompatible with vvvvvvvvvvvvvvvvvvvvvv -- #3731
+ def map[A,B](f : A => B) /* : Stream[A] => Stream[B]*/ = ZipWith(f)
+ val tst: Stream[Int] = map{x: String => x.length}(Stream("a"))
+} \ No newline at end of file