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import scala.testing.SUnit._
object Test {
def main(args:Array[String]) = {
Foo.run
Mas.run
LisSeqArr.run
StreamFoo.run
}
}
// this class is used for representation
class Bar {
var size: Int = 50
var name: String = "medium"
}
// test basic unapply for 0, 1 and 2 args and with precise type test
object Fii {
def unapply(x: Any): boolean = x.isInstanceOf[Bar]
}
object Faa {
def unapply(x: Any): Option[String] = if(x.isInstanceOf[Bar]) Some(x.asInstanceOf[Bar].name) else None
}
object FaaPrecise {
def unapply(x: Bar): Option[String] = Some(x.name)
}
object FaaPreciseSome {
def unapply(x: Bar) = Some(x.name) // return type Some[String]
}
object Foo extends Assert {
def unapply(x: Any): Option[Product2[Int, String]] = x match {
case y: Bar => Some(Tuple(y.size, y.name))
case _ => None
}
def doMatch1(b:Bar) = b match {
case Foo(s:Int, n:String) => (s,n)
}
def doMatch2(b:Bar) = b match {
case Fii() => null
}
def doMatch3(b:Bar) = b match {
case Faa(n:String) => n
}
def doMatch4(b:Bar) = (b:Any) match {
case FaaPrecise(n:String) => n
}
def doMatch5(b:Bar) = (b:Any) match {
case FaaPreciseSome(n:String) => n
}
def run {
val b = new Bar
assertEquals(doMatch1(b),(50,"medium"))
assertEquals(doMatch2(b),null)
assertEquals(doMatch3(b),"medium")
assertEquals(doMatch4(b),"medium")
assertEquals(doMatch5(b),"medium")
}
}
// same, but now object is not top-level
object Mas extends Assert {
object Gaz {
def unapply(x: Any): Option[Product2[Int, String]] = x match {
case y: Baz => Some(Tuple(y.size, y.name))
case _ => None
}
}
class Baz {
var size: Int = 60
var name: String = "too large"
}
def run {
val b = new Baz
assertEquals(b match {
case Gaz(s:Int, n:String) => (s,n)
}, (60,"too large"))
}
}
object LisSeqArr extends Assert {
def run {
assertEquals((List(1,2,3): Any) match { case List(x,y,_*) => (x,y)}, (1,2))
assertEquals((List(1,2,3): Any) match { case Seq(x,y,_*) => (x,y)}, (1,2))
assertEquals((Array(1,2,3): Any) match { case Seq(x,y,_*) => (x,y)}, (1,2))
//assertEquals((Array(1,2,3): Any) match { case Array(x,y,_*) => {x,y}}, {1,2})
}
}
object StreamFoo extends TestCase("unapply for Streams") with Assert {
//val x:Stream[Int] = Stream.cons(1,x)
def sum(stream: Stream[int]): int =
stream match {
case Stream.empty => 0
case Stream.cons(hd, tl) => hd + sum(tl)
}
override def run {
val str: Stream[int] = Stream.fromIterator(List(1,2,3).elements)
assertEquals(sum(str), 6)
}
}
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