打印执行时间 in Swift

如何在 Swift 中打印某个函数的执行时间首先，我们需要在类中定义一个 ContinuousClock 属性

//打印函数执行时间
    var clock = ContinuousClock()

    func logTime(duration: ContinuousClock.Duration, function: String = #function) {
        print("\(function) Time taken = \(duration)")
    }

     func someMethod() {
        let startInstant = clock.now
        defer { logTime(duration: clock.now - startInstant) }
     }