func (b *Blog) IsFieldZero(field *mapping.StructField) (bool, error) {
	switch field.Index[0] {
	case 0: // ID
		return b.ID == 0, nil
	case 1: // CreatedAt
		return b.CreatedAt == time.Time{}, nil
	case 2: // Title
		return b.Title == "", nil
	case 5: // TopPostID
		return b.TopPostID == 0, nil
	}
	return false, errors.Wrapf(mapping.ErrInvalidModelField, "provided invalid field name: '%s'", field.Name())
}
// IsFieldZero implements mapping.Fielder interface.
IsFieldZero implements mapping.Fielder interface.
// IsFieldZero implements mapping . Fielder interface .
func (b *Blog) IsFieldZero(field *mapping.StructField) (bool, error) {
	switch field.Index[0] {
	case 0: 
		return b.ID == 0, nil
	case 1: 
		return b.CreatedAt == time.Time{}, nil
	case 2: 
		return b.Title == "", nil
	case 5: 
		return b.TopPostID == 0, nil
	}
	return false, errors.Wrapf(mapping.ErrInvalidModelField, "provided invalid field name: '%s'", field.Name())
}
func ( b * Blog ) IsFieldZero ( field * mapping . StructField ) ( bool , error ) { switch field . Index [ 0 ] { case 0 : return b . ID == 0 , nil case 1 : return b . CreatedAt == time . Time { } , nil case 2 : return b . Title == " " , nil case 5 : return b . TopPostID == 0 , nil } return false , errors . Wrapf ( mapping . ErrInvalidModelField , " " , field . Name ( ) ) }
IsFieldZero implements mapping.Fielder interface.
IsFieldZero implements mapping . Fielder interface .
// ID // CreatedAt // Title // TopPostID