戻り値の型はOption[A]でした
def find(p: (A) ⇒ Boolean): Option[A] Finds the first element of the sequence satisfying a predicate, if any.
Scala Standard Library 2.12.3 - scala.collection.immutable.List
戻り値の型はOption[A]でした
def find(p: (A) ⇒ Boolean): Option[A] Finds the first element of the sequence satisfying a predicate, if any.
Scala Standard Library 2.12.3 - scala.collection.immutable.List