我写了以下规范
"An IP4 address" should "belong to just one class" in {
val addrs = for {
a <- Gen.choose(0, 255)
b <- Gen.choose(0, 255)
c <- Gen.choose(0, 255)
d <- Gen.choose(0, 255)
} yield s"$a.$b.$c.$d"
forAll (addrs) { ip4s =>
var c: Int = 0
if (IP4_ClassA.unapply(ip4s).isDefined) c = c + 1
if (IP4_ClassB.unapply(ip4s).isDefined) c = c + 1
if (IP4_ClassC.unapply(ip4s).isDefined) c = c + 1
if (IP4_ClassD.unapply(ip4s).isDefined) c = c + 1
if (IP4_ClassE.unapply(ip4s).isDefined) c = c + …