code: func (v *Validator) Match(field string, regex *regexp.Regexp) *ValidationResult {
  	if !regex.MatchString(v.data.Get(field)) {
  		return v.addMatchError(field)
  	} else {
  		return validationOk
  	}
  }
docs: // Match will add an error to the Validator if data.Values[field] does
  // not match the regular expression regex.