Scala，使用部分函數參數和隱式參數

Question

當我運行以下代碼時，出現一些錯誤：

Error:(15, 25) missing parameter type for expanded function
The argument types of an anonymous function must be fully known. (SLS 8.5)
Expected type was: ?
  testFuture onComplete({
                    ^

碼：

object TestFuture extends App{

val exe = ExecutionContext.fromExecutor(Executors.newCachedThreadPool())

testFuture onComplete({
case Success((str,i)) =>{
  println(str,i)
}
case Failure(e) =>{
  e.printStackTrace()
}})(exe)


println(Runtime.getRuntime.availableProcessors())
Thread.sleep(2000)

def testFuture:Future[(String,Int)] = Future[(String,Int)] {
  Thread.sleep(1000)
  ("oh my sky",12)
}(exe)
}

當我用“隱式”修飾“ val exe”並調用currying函數而沒有像下面的代碼那樣顯式使用“ exe”時，它運行正確。 你能告訴我為什么嗎？

object TestFuture extends App{
implicit val exe = ExecutionContext.fromExecutor(Executors.newCachedThreadPool())

testFuture onComplete({
case Success((str,i)) =>{
  println(str,i)
}
case Failure(e) =>{
  e.printStackTrace()
}})


println(Runtime.getRuntime.availableProcessors())
Thread.sleep(2000)

def testFuture:Future[(String,Int)] = Future[(String,Int)] {
  Thread.sleep(1000)
  ("oh my sky",12)
}
}

Answer 1

我猜想，infix方法調用不支持多個參數列表。 嘗試使用點符號：

testFuture.onComplete{
  case Success((str,i)) =>
    println(s"$str, $i")
  case Failure(e) =>
    e.printStackTrace()
}(exe)