下面的类在这一行抛出编译器错误 val userList : List[User]
:
Multiple markers at this line
- only classes can have declared but undefined members
- only classes can have declared but undefined members
完整代码如下:
class SimilarityData {
case class User(id: String, jCoeff : Int)
def getUsers() =
{
val userList : List[User]
userList :+ new User("1" , 1);
}
}
是什么导致了这个错误?
最佳答案
您必须为本地 val
提供初始值:
val userList = List(new User("1", 1))
错误提醒您:
a
val
必须分配了一个初始值,在您的情况下是方法主体中的本地值。抽象类或特征上的
<val
可能未初始化 - 尽管它必须由沿线某处的(具体)子类初始化,
关于Scala 编译器错误 : only classes can have declared but undefined members,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17815302/