Question

我是Scala的新手，在这里我试图找到1到100之间的偶数，因此在进行过滤时，我会得到

scala.collection.immutable.Range.Inclusive

scala> var a = List(1 to 100)
a: List[scala.collection.immutable.Range.Inclusive] = List(Range(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100))

scala> a.filter(x => (x % 2 == 0))
<console>:26: error: value % is not a member of scala.collection.immutable.Range.Inclusive
       a.filter(x => (x % 2 == 0))
                        ^

scala> val b = a.filter(x => x % 2 == 0)
<console>:25: error: value % is not a member of scala.collection.immutable.Range.Inclusive
       val b = a.filter(x => x % 2 == 0)
                               ^

Answer 1

您无需将Range包裹在List中，只需执行以下操作：

val a = 1 to 100

a.filter(x => x % 2 == 0)

Answer 2

您正在创建Range的列表，而不是整数在该范围内的列表。为此，将其更改为：

val a = (1 to 10).toList

但是@Tim是对的，您可以直接在filter上Range

我在提交文件时收到错误消息，称“值％不是scala.collection.immutable.Range.Inclusive的成员”

2 个答案: