我有這樣的域對象:斯卡拉+ MongoDB的:可選字段和immutables
case class Person (
name : String,
age: Option[Int],
email : String
) extends MongoObject
隨着年齡的可選字段。所以我定義我廠:
object Person extends MongoObjectShape[Person] {
lazy val name = Field.scalar("name", _.name)
lazy val age = Field.optional("age", t => t.age)
lazy val email = Field.scalar("email", _.email)
override lazy val * = name :: age :: email :: Nil
override def factory(dbo: DBObject): Option[Person] =
for {
n <- name from dbo
t <- age from dbo
z <- email from dbo
} yield new Person(n, t, z)
}
,但它並沒有編譯,因爲我得到:
[error] found : Int
[error] required: Option[Int]
[error] } yield new Person(n, t, z)
[error] ^
有什麼不對呢?
謝謝包裝ŧ , 有用。當然,我必須在Scala中學習更多關於模式匹配的知識。 – onof 2010-12-17 18:32:35