D语言中秒的计算单位定义
秒: seconds 毫秒: msecs 微秒: usecs 纳秒: nsecs
其中:
1.seconds = 1000.msecs 1.msecs = 1000.usecs 1.usecs = 1000.nsecs
具体使用方法可参照官方文档:https://dlang.org/phobos/core_time.html#seconds