abstract final class Nothing extends Any

Nothing is - together with scala.Null - at the bottom of Scala’s type hierarchy.

Nothing is a subtype of every other type (including scala.Null); there exist no instances of this type. Although type Nothing is uninhabited, it is nevertheless useful in several ways. For instance, the Scala library defines a value scala.collection.immutable.Nil of type List[Nothing] . Because lists are covariant in Scala, this makes scala.collection.immutable.Nil an instance of List[T] , for any element of type T .

Another usage for Nothing is the return type for methods which never return normally. One example is method error in scala.sys, which always throws an exception.

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