Mah*_*hdi 4 scala pattern-matching case-class akka
我有这样的事情:
class ProbeActor extends Actor {
case class Probe(messageKey: String)
def receiveProbe: Receive = {
case Probe(probeKey) => println("Good probe: "+probeKey)
case x => println("Bad probe: "+ x)
}
final override def receive = receiveProbe orElse receiveOther
def receiveOther: Receive = {
case _ => println("Other")
}
}
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我称之为:
class Prober extends ProbeActor {
val definite = ActorSystem("ProbeTest").actorOf(Props[ProbeActor], name = "probed")
implicit val timeout = Timeout(5 second)
val future = definite ? Probe("key")
}
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我希望文本"Good probe: key"应该打印,但我明白了"Bad probe: Probe(key)".
注意:如果我将Probe案例类放在外面,那么它可以正常工作.
经过更多搜索,我在scala-lang.org上找到了答案:
我认为潜在的误解是关于嵌套类类型的身份.
在
A级{B级}
类A x的每个新实例都创建一个新类型xB如果你在A内部进行普通模式匹配,则指的是类型B this.B的特定实例.
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