scala - Future 不是 scala.concurrent 的成员

Question

我收到错误 Future is not a member of scala.concurrent导入 Future 时类(class)。

~/workspace/experiments $ scala
Welcome to Scala version 2.9.2 (OpenJDK 64-Bit Server VM, Java 1.7.0_151).
Type in expressions to have them evaluated.
Type :help for more information.

scala> import scala.concurrent.Future
<console>:7: error: Future is not a member of scala.concurrent
       import scala.concurrent.Future
              ^

scala>

我在 Ubuntu 14.04 上运行它:

~/workspace/experiments $ cat /etc/lsb-release                                                 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.5 LTS"

有谁知道我做错了什么？

Answer 1

升级您的 Scala 版本应该可以解决它。在 scala 2.9.2 中，Future 似乎不是 scala.concurrent 的成员
看
http://www.scala-lang.org/api/2.9.2/#scala.concurrent.package

与 http://www.scala-lang.org/api/2.11.8/#scala.concurrent.package