如何对具有多个参数列表的类进行模式匹配？

class DateTime(year: Int, month: Int, day: Int)(hour: Int, minute: Int, second: Int)

dt match {
  case DateTime(2012, 12, 12)(12, _, _) => // December 12th 2012, 12 o\'clock
  /* ... */
}

def unapply(dt: DateTime) = 
  Some((dt.year, dt.month, dt.day),(dt.hour, dt.minute, dt.second))

scala> case class A(i: Int)(j: Int) { }
defined class A

scala> A(5)(4) match { case A(5) => \"Hi\" }
res14: java.lang.String = Hi

scala> A(5)(4) == A(5)(9)
res15: Boolean = true

case class Time(hour: Int, minute: Int, second: Int) { }
case class Date(year: Int, month: Int, day: Int) { }
case class DateTime(date: Date, time: Time) { }

scala> val dt = DateTime(Date(2011,5,27), Time(15,21,50))
scala> dt match { case DateTime(Date(2011,_,_),Time(h,m,50)) => println(h + \":\" + m) }
15:21

Some((a,b),(x,y))

Some(((a,b,c),(x,y,z)))

Tuple2[Tuple3[A,B,C],Tuple3[X,Y,Z]]