返回时间。时间零值当函数有错误时
const timeFormat = "15 Monday January 2006"
func ParseDate(s string) (time.Time, error) {
t, err := time.Parse(timeFormat, s)
if err != nil {
// time.Time{} returns January 1, year 1, 00:00:00.000000000 UTC
// which according to the source code is the zero value for time.Time
// https://golang.org/src/time/time.go#L23
return time.Time{}, err
}
return t, nil
}