scala> :settings -Wunused:all

scala> import scala.collection.*

scala> class Foo { import scala.util.*; println("foo") }
1 warning found
-- [E198] Unused Symbol Warning: -----------------------------------------------
1 |class Foo { import scala.util.*; println("foo") }
  |                              ^
  |                              unused import
// defined class Foo

scala> { import scala.util.*; "foo" }
val res0: String = "foo"
