Question

我想在通用Try[T]处理程序中重构一些常见的错误处理逻辑，类似于：

def handler[T](t: Try[T], successFunc: T => Unit) = {

  t.map {
    case Success(res) => { // type mismatch required T, found Any (in successFunc line)
    //case Success(res: T) => { // Type abstract type pattern T is unchecked since it is eliminated by erasure
      successFunc(res)
    }
    case Failure(e: CustomException) => {
      // custom actions
    }
    case Failure(e) => {
      // custom actions
    } 
  }
}

似乎由于类型擦除，我无法与类型T匹配。但我无法将Any传递给successFunc。

如何实现此功能？

Answer 1

尝试映射会将函数应用于该尝试成功所持有的值，您所拥有的值不是Success或Failure，而是T，你想要的是match：

def handler[T](t: Try[T], successFunc: T => Unit) = {
  t match {
    case Success(res) =>
      successFunc(res)
    case Failure(e: FileNotFoundException) =>
    case Failure(e) =>
  }
}

map案例中的用法是：

t.map(someT => successFunc(someT))

通用Try [T]函数

1 个答案: