为什么不映射到Try在这种情况下删除Try(Why doesn't mapping over a Try remove the Try in this case)

为什么不映射到Try在这种情况下删除Try(Why doesn't mapping over a Try remove the Try in this case) // redis.get(key) returns a Option[A] redis.get(key).map(x => Try(x.toInt)).map(counter => doSomething(counter))

我收到一个错误，因为doSomething想要一个Int，但我传递了一个Try [Int]。

我认为Try上的映射会删除它，但它似乎没有工作。

我在这里想念的是什么？

// redis.get(key) returns a Option[A] redis.get(key).map(x => Try(x.toInt)).map(counter => doSomething(counter))

I am getting an error because doSomething wants an Int but I am passing a Try[Int].

I thought mapping on the Try would remove it, but it doesn't seem to be working.

What am I missing here?

最满意答案

Parens在错误的地方。 正如Michael Zajac所说，你正在映射Option ，而不是Try 。

固定：

redis.get(key).map(x => Try(x.toInt).map(counter => doSomething(counter)))

Parens in the wrong place. As Michael Zajac said, you're mapping the Option, not the Try.

Fixed:

redis.get(key).map(x => Try(x.toInt).map(counter => doSomething(counter)))