fixed 1275 by adding minimal early check to Nam...

fixed 1275 by adding minimal early check to Namers so that overriding of type members in refinements cannot change number of type parameters (in principle the full overriding checks should be performed at a later point, when they don't cause cyclicity errors -- this is TODO)

1 files changed, 14 insertions, 0 deletions

diff --git a/test/files/neg/bug1275.scala b/test/files/neg/bug1275.scala
new file mode 100644
index 0000000000..04c66400c8
--- /dev/null
+++ b/test/files/neg/bug1275.scala
@@ -0,0 +1,14 @@
+// tested using Scala compiler version 2.6.0-RC1 -- (c) 2002-2007 LAMP/EPFL
+
+// prompted by "Covariant return types" mailing list question
+object TestCovariance {
+
+    // see  Type constructor polymorphism  in  http://www.scala-lang.org/docu/changelog.html
+    trait Seq[+t] {
+        type MyType[+t] <: Seq[t]
+
+        def f: MyType[t]
+    }
+
+    def span[a, s <: Seq[a] { type MyType <: s } ](xs: s): s = xs f
+}