Question

我正在编写一个基于Log的项目中使用的日志记录类。

在Log中，日志记录方法就像这样调用

open func trace(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(.trace, items, separator, terminator, file, line, column, function)
}

open func debug(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(.debug, items, separator, terminator, file, line, column, function)
}

open func info(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(.info, items, separator, terminator, file, line, column, function)
}

open func warning(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(.warning, items, separator, terminator, file, line, column, function)
}

open func error(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(.error, items, separator, terminator, file, line, column, function)
}

这些都可以正常工作，但我发现代码过于重复，并希望使用Generic T类型的单一方法替换它

open func log<T: Level>(_ items: Any..., separator: String = " ", terminator: String = "\n", file: String = #file, line: Int = #line, column: Int = #column, function: String = #function) {
    log(T, items, separator, terminator, file, line, column, function)
}

我提出的方法是

class public func log<T: LogLevelGeneric>(_ items: Any..., separator: String = "", _ file: String = #file, _ line: Int = #line, _ function: String = #function, t:T) {
         // Error: Inheritance from non-protocol, non-class type LogLevelGeneric

}


public enum LogLevelGeneric: String {
    case pretty  = "Prettify"
    case measure = "Measure "
    case verbose = "Verbose "
    case info    = "Info    "
    case warning = "Warning "
    case debug   = "Debug   "
    case error   = "❤️️Error   "
}

搜索谷歌和stackoverflow，香港专业教育学院发现我试图做的事情可以实现，但它不能，到目前为止我只是证明它无法完成。

有人能指出我如何做到这一点的正确方向？感谢。

Answer 1

错误消息表明您不能将枚举用作通用约束。

实际上，您不需要通用功能，将该级别作为参数传递，例如

class public func log(level: LogLevelGeneric, items: Any..., separator: String = "", _ file: String = #file, _ line: Int = #line, _ function: String = #function) {


}

我如何在泛型类中使用枚举值

1 个答案: