我一直在这里寻找很多问题,我找到了一个类似标题
Enum case switch not found in type,但没有解决方案.
我想使用带有自身变异的枚举来解决问题,在个别状态下,下一个交通灯颜色是什么.
- enum TrafficLights {
- mutating func next() {
- switch self {
- case .red:
- self = .green
- case .orange:
- self = .red
- case .green:
- self = .orange
- case .none:
- self = .orange
- }
- }
- }
我已将所有案例作为可能的选项,它仍然返回错误：
Enum ‘case’ not found in type ‘TrafficLights’
@H_403_10@
案例必须在函数之外声明：
- enum TrafficLights {
- case green
- case red
- case orange
- case none
- mutating func next() {
- switch self {
- case .red:
- self = .green
- case .orange:
- self = .red
- case .green:
- self = .orange
- case .none:
- self = .orange
- }
- }
- }
