I wrote a warning when nullary methods return U...

I wrote a warning when nullary methods return Unit. I wimped out of
including it in this patch because we had about 200 of them, and that's
what is fixed in this patch. I will add the warning to some kind of
"-Xlint" feature after 2.9.

This is motivated at least partly by the resolution of #4506, which
indicates the distinction between "def foo()" and "def foo" will
continue to jab its pointy stick into our eyes, so I believe we have a
minimal duty of at least following our own advice about what they mean
and not making a semirandom choice as to whether a method has parens or
not. Review by community.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/library/scala/collection/mutable/ObservableBuffer.scala b/src/library/scala/collection/mutable/ObservableBuffer.scala
index aa9bd7ac95..c38bf5fbf3 100644
--- a/src/library/scala/collection/mutable/ObservableBuffer.scala
+++ b/src/library/scala/collection/mutable/ObservableBuffer.scala
@@ -46,7 +46,7 @@ trait ObservableBuffer[A] extends Buffer[A] with Publisher[Message[A] with Undoa
     val oldelement = apply(n)
     super.update(n, newelement)
     publish(new Update(Index(n), newelement) with Undoable {
-      def undo { update(n, oldelement) }
+      def undo() { update(n, oldelement) }
     })
   }
 
@@ -54,7 +54,7 @@ trait ObservableBuffer[A] extends Buffer[A] with Publisher[Message[A] with Undoa
     val oldelement = apply(n)
     super.remove(n)
     publish(new Remove(Index(n), oldelement) with Undoable {
-      def undo { insert(n, oldelement) }
+      def undo() { insert(n, oldelement) }
     })
     oldelement
   }
@@ -62,7 +62,7 @@ trait ObservableBuffer[A] extends Buffer[A] with Publisher[Message[A] with Undoa
   abstract override def clear(): Unit = {
     super.clear
     publish(new Reset with Undoable {
-      def undo { throw new UnsupportedOperationException("cannot undo") }
+      def undo() { throw new UnsupportedOperationException("cannot undo") }
     })
   }
 }