public static ValidationRule <TField> WithFailMessage <TField>(this ValidationRule <TField> rule,
                                                                string failMessage) where TField : IFieldViewModel
 {
     rule.FailMessage = failMessage;
     return(rule);
 }
 public static ValidationRule <TField> WithSpecification <TField>(this ValidationRule <TField> rule,
                                                                  Specification <TField> specification) where TField : IFieldViewModel
 {
     rule.Specification = specification;
     return(rule);
 }
 public static ValidationRule <TField> WithSuccessMessage <TField>(this ValidationRule <TField> rule,
                                                                   string successMessage) where TField : IFieldViewModel
 {
     rule.SuccessMessage = successMessage;
     return(rule);
 }