// errmsg.gopackage mainimport (	"errors"	"fmt")type DivideError struct {	dividee int	divider int}func (de *DivideError) Error() string {	strFormat := `		Cannot proceed, the divider is zero.		dividee: %d		divider: %d	`	return fmt.Sprintf(strFormat, de.dividee, de.divider)}func PrintErrTest() error {	return errors.New("error!!!!")}func Divide(varDividee int, varDivider int) (result int, errormsg string) {	if varDivider == 0 {		dData := DivideError{			dividee: varDividee,			divider: varDivider,		}		errormsg = dData.Error()		return	} else {		return varDividee / varDivider, ""	}}func main() {	//  1	error := PrintErrTest()	if error != nil {		fmt.Println(error)	}	// 2	if result, errorMsg := Divide(100, 10); errorMsg == "" {		fmt.Println("100/10 =", result)	}	if _, errorMsg := Divide(100, 0); errorMsg != "" {		fmt.Println("errorMsg is :", errorMsg)	}}

输出：

error!!!!100/10 = 10errorMsg is : 		Cannot proceed, the divider is zero.		dividee: 100		divider: 0