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object Test {
def main(args: Array[String]): Unit = {
Foo.run()
Mas.run()
LisSeqArr.run()
StreamFoo.run()
Test1256.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 VarFoo {
def unapply(a : Int)(implicit b : Int) : Option[Int] = Some(a + b)
}
object Foo {
def unapply(x: Any): Option[Product2[Int, String]] = x match {
case y: Bar => Some(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(): Unit = {
val b = new Bar
assert(doMatch1(b) == (50,"medium"))
assert(doMatch2(b) == null)
assert(doMatch3(b) == "medium")
assert(doMatch4(b) == "medium")
assert(doMatch5(b) == "medium")
implicit val bc: Int = 3
assert(7 == (4 match {
case VarFoo(x) => x
}))
}
}
// same, but now object is not top-level
object Mas {
object Gaz {
def unapply(x: Any): Option[Product2[Int, String]] = x match {
case y: Baz => Some(y.size, y.name)
case _ => None
}
}
class Baz {
var size: Int = 60
var name: String = "too large"
}
def run(): Unit = {
val b = new Baz
assert((60,"too large") == (b match {
case Gaz(s:Int, n:String) => (s,n)
}))
}
}
object LisSeqArr {
def run(): Unit = {
assert((1,2) == ((List(1,2,3): Any) match { case List(x,y,_: _*) => (x,y)}))
assert((1,2) == ((List(1,2,3): Any) match { case Seq(x,y,_: _*) => (x,y)}))
}
}
object StreamFoo {
def sum(stream: Stream[Int]): Int =
stream match {
case Stream.Empty => 0
case Stream.cons(hd, tl) => hd + sum(tl)
}
def run(): Unit = {
val str: Stream[Int] = List(1,2,3).toStream
assert(6 == sum(str))
}
}
object Test1256 {
class Sync {
def unapply(scrut: Any): Boolean = false
}
class Buffer {
val Get = new Sync
val jp: PartialFunction[Any, Any] = {
case Get() =>
}
}
def run(): Unit = {
assert(!(new Buffer).jp.isDefinedAt(42))
}
}
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