scala - 无法从无形中重现 Monoid 示例

Question

我尝试从以下位置重现 Monoid 示例：https ://github.com/milessabin/shapeless/blob/master/examples/src/main/scala/shapeless/examples/monoids.scala

scala> import shapeless._
import shapeless._

scala> import MonoidSyntax._
<console>:10: error: not found: value MonoidSyntax
       import MonoidSyntax._
          ^

scala> import Monoid.auto._
<console>:10: error: not found: value Monoid
       import Monoid.auto._

我尝试使用 Shapeless-2.0.0-SNAPSHOT 和 Shapeless-2.0.0-M1。我还需要一些其他的东西吗？

谢谢费边

Answer 1

The problem was that i missed the Monoid part of the example...