Tighten isStable predicate

A term ref is stable only if its prefix is also stable. At the same time, we
drop stability requirements where they no longer make sense (e.g. in isLegalPrefix).

1 files changed, 0 insertions, 7 deletions

diff --git a/tests/neg/projections.scala b/tests/neg/projections.scala
deleted file mode 100644
index 5d80e1151..000000000
--- a/tests/neg/projections.scala
+++ /dev/null
@@ -1,7 +0,0 @@
-class projections {
-
-  class Lambda { type Arg; type Apply }
-
-  var x: (Lambda { type Apply = Int }) # Apply = _ // error: illegal prefix
-
-}