golang 自定义错误示例

package mainimport ( "fmt" "time")// MyError is an error implementation that includes a time and message.type MyError struct { When time.Time What string}func (e MyError) Error() string { return fmt.Sprintf("%v: %v", e.When, e.What)}func oops() error { return MyError{  time.Date(1989, 3, 15, 22, 30, 0, 0, time.UTC),  "the file system has gone away", }}func Example() { if err := oops(); err != nil {  fmt.Println(err) } // Output: 1989-03-15 22:30:00 +0000 UTC: the file system has gone away}func main() { Example()}

下面的代码也来自golang源码，记录以用