scala - 如何在 Scala 中创建一组字符？

Question

我想在 Scala 中创建一组字符范围，例如 A..Za..z0..9。这是我的看法:

scala> ('A' to 'Z').toSet.union(('a' to 'z').toSet).union(('0' to '9').toSet)
res3: scala.collection.immutable.Set[Char] = Set(E, e, X, s, x, 8, 4, n, 9, N, j, y, T, Y, t, J, u, U, f, F, A, a, 5, m, M, I, i, v, G, 6, 1, V, q, Q, L, b, g, B, l, P, p, 0, 2, C, H, c, W, h, 7, r, K, w, R, 3, k, O, D, Z, o, z, S, d)

这不是做到这一点的惯用方式。什么是更好的方法？

Answer 1

这个怎么样:

scala> ('a' to 'z').toSet ++ ('A' to 'Z') ++ ('0' to '9')
res0: scala.collection.immutable.Set[Char] = Set(E, e, X, s, x, 8, 4, n, 9, N, j, y, T, Y, t, J, u, U, f, F, A, a, 5, m, M, I, i, v, G, 6, 1, V, q, Q, L, b, g, B, l, P, p, 0, 2, C, H, c, W, h, 7, r, K, w, R, 3, k, O, D, Z, o, z, S, d)

或者，或者:

scala> (('a' to 'z') ++ ('A' to 'Z') ++ ('0' to '9')).toSet
res0: scala.collection.immutable.Set[Char] = Set(E, e, X, s, x, 8, 4, n, 9, N, j, y, T, Y, t, J, u, U, f, F, A, a, 5, m, M, I, i, v, G, 6, 1, V, q, Q, L, b, g, B, l, P, p, 0, 2, C, H, c, W, h, 7, r, K, w, R, 3, k, O, D, Z, o, z, S, d)