scope.Debugf("validatePortNumberString %v:", val)
	if !util.IsString(val) {
		return util.NewErrs(fmt.Errorf("validatePortNumberString(%s) bad type %T, want string", path, val))
	}
	if val.(string) == "*" || val.(string) == "" {
		return nil
	}
	intV, err := strconv.ParseInt(val.(string), 10, 32)
	if err != nil {
		return util.NewErrs(fmt.Errorf("%s : %s", path, err))
	}
	return validatePortNumber(path, intV)
}

	case int64:
		return v, nil
	case int:
		return int64(v), nil
	case string:
		i, err := strconv.Atoi(v)
		return int64(i), err
	default:
		return 0, errors.New("Invalid number format")
	}
}

// isString - Safely check if val is of type string without causing panic.
func isString(val interface{}) bool {
	_, ok := val.(string)
	return ok
}

// ContentLengthRange - policy content-length-range field.

// If explicit is true, then conversions from integer to string are
// also allowed.
func ConvertVal(v constant.Value, t *types.Type, explicit bool) constant.Value {
	switch ct := v.Kind(); ct {
	case constant.Bool:
		if t.IsBoolean() {
			return v
		}

	case constant.String:
		if t.IsString() {
			return v
		}

	case constant.Int:
		if explicit && t.IsString() {
			return tostr(v)
		}
		fallthrough

func isFloat(t Type) bool          { return isBasic(t, IsFloat) }
func isComplex(t Type) bool        { return isBasic(t, IsComplex) }
func isNumeric(t Type) bool        { return isBasic(t, IsNumeric) }
func isString(t Type) bool         { return isBasic(t, IsString) }
func isIntegerOrFloat(t Type) bool { return isBasic(t, IsInteger|IsFloat) }
func isConstType(t Type) bool      { return isBasic(t, IsConstType) }

		v1.AddArg2(v2, mem)
		v.AddArg2(v0, v1)
		return true
	}
	// match: (Load <t> ptr mem)
	// cond: t.IsString()
	// result: (StringMake (Load <typ.BytePtr> ptr mem) (Load <typ.Int> (OffPtr <typ.IntPtr> [config.PtrSize] ptr) mem))
	for {
		t := v.Type
		ptr := v_0
		mem := v_1
		if !(t.IsString()) {
			break
		}
		v.reset(OpStringMake)
		v0 := b.NewValue0(v.Pos, OpLoad, typ.BytePtr)
		v0.AddArg2(ptr, mem)

    public val KaType.isBoolean: Boolean get() = withValidityAssertion { isClassTypeWithClassId(DefaultTypeClassIds.BOOLEAN) }
    public val KaType.isString: Boolean get() = withValidityAssertion { isClassTypeWithClassId(DefaultTypeClassIds.STRING) }
    public val KaType.isCharSequence: Boolean get() = withValidityAssertion { isClassTypeWithClassId(DefaultTypeClassIds.CHAR_SEQUENCE) }

	valid := false
	length := int64(-1) // valid if >= 0
	switch typ := under(x.typ).(type) {
	case *Basic:
		if isString(typ) {
			valid = true
			if x.mode == constant_ {
				length = int64(len(constant.StringVal(x.val)))
			}
			// an indexed string always yields a byte value
			// (not a constant) even if the string and the
			// index are constant
			x.mode = value
			x.typ = universeByte // use 'byte' name
		}

	valid := false
	length := int64(-1) // valid if >= 0
	switch typ := under(x.typ).(type) {
	case *Basic:
		if isString(typ) {
			valid = true
			if x.mode == constant_ {
				length = int64(len(constant.StringVal(x.val)))
			}
			// an indexed string always yields a byte value
			// (not a constant) even if the string and the
			// index are constant
			x.mode = value
			x.typ = universeByte // use 'byte' name
		}

func isFloat(t Type) bool          { return isBasic(t, IsFloat) }
func isComplex(t Type) bool        { return isBasic(t, IsComplex) }
func isNumeric(t Type) bool        { return isBasic(t, IsNumeric) }
func isString(t Type) bool         { return isBasic(t, IsString) }
func isIntegerOrFloat(t Type) bool { return isBasic(t, IsInteger|IsFloat) }
func isConstType(t Type) bool      { return isBasic(t, IsConstType) }

		base.Errorf("invalid operation: %v (type %v does not support indexing)", n, t)
		n.SetType(nil)
		return n

	case types.TSTRING, types.TARRAY, types.TSLICE:
		n.Index = indexlit(n.Index)
		if t.IsString() {
			n.SetType(types.ByteType)
		} else {
			n.SetType(t.Elem())
		}
		why := "string"
		if t.IsArray() {
			why = "array"
		} else if t.IsSlice() {
			why = "slice"
		}