}
	return []string{InclusiveRangeError(minUserID, maxUserID)}
}

var portNameCharsetRegex = regexp.MustCompile("^[-a-z0-9]+$")
var portNameOneLetterRegexp = regexp.MustCompile("[a-z]")

// IsValidPortName check that the argument is valid syntax. It must be
// non-empty and no more than 15 characters long. It may contain only [-a-z0-9]
// and must contain at least one letter [a-z]. It must not start or end with a

	for _, val := range goodValues {
		if msgs := IsValidPortName(val); len(msgs) != 0 {
			t.Errorf("expected true for %q: %v", val, msgs)
		}
	}

	badValues := []string{"longerthan15characters", "", strings.Repeat("a", 16), "12345", "1-2-3-4", "-begin", "end-", "two--hyphens", "whois++"}
	for _, val := range badValues {
		if msgs := IsValidPortName(val); len(msgs) == 0 {
			t.Errorf("expected false for %q", val)
		}

			}
		} else {
			if port.EndPort != nil {
				allErrs = append(allErrs, field.Invalid(portPath.Child("endPort"), *port.EndPort, "may not be specified when `port` is non-numeric"))
			}
			for _, msg := range validation.IsValidPortName(port.Port.StrVal) {
				allErrs = append(allErrs, field.Invalid(portPath.Child("port"), port.Port.StrVal, msg))
			}
		}
	} else {
		if port.EndPort != nil {