diff options
-rw-r--r-- | src/library/scala/collection/immutable/Set.scala | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/library/scala/collection/immutable/Set.scala b/src/library/scala/collection/immutable/Set.scala index 7c5138d700..a90c20fb69 100644 --- a/src/library/scala/collection/immutable/Set.scala +++ b/src/library/scala/collection/immutable/Set.scala @@ -17,6 +17,10 @@ package scala.collection.immutable; * <code>scala.collection.Set</code> as well as for <code>+</code> and * <code>-</code>. * + * Note that abstract immutable.Set's are not covariant in their type + * parameter. This is because some subclasses cannot support the + * <code>+</code> method for arbitrary types. + * * @author Matthias Zenger * @version 1.1, 03/05/2004 */ |