普通に非推奨でしょう。。。
パターンマッチのところに@uncheckedをつけると、match is not exhaustiveのwarningを回避できる。
object Test extends App { // This would normally warn "match is not exhaustive" // because `None` is not covered. def f(x: Option[String]) = (x: @unchecked) match { case Some(y) => y } // This would normally warn "type pattern is unchecked" // but here will blindly cast the head element to String. def g(xs: Any) = xs match { case x: List[String @unchecked] => x.head } }
@uncheckedのアノテーションについて。