Empty type on xsd:element not handled as anyType ?

[Eusebiotrigo]

Description

I am using xgen to generate code in go.

The xsd extract is:

<xsd:complexType name="AccountHolder_Type">
xsd:sequence
xsd:choice
<xsd:element name="Individual" type="dpi:NameReportableSeller_Type"/>
xsd:sequence
<xsd:element name="Organisation" type="dpi:OrganisationParty_Type"/>
<xsd:element name="AcctHolderType"/>
</xsd:sequence>
</xsd:choice>
</xsd:sequence>
</xsd:complexType>

and the code generated for that Type is:

type AccountHolderType struct {
XMLName xml.Name xml:"AccountHolder_Type"
Individual *NameReportableSellerType xml:"Individual"
Organisation *OrganisationPartyType xml:"Organisation"
AcctHolderType *AcctHolderType xml:"AcctHolderType"
}

And that AcctHolderType points to nothing, and, to be honest, not sure if it should generate a type or a string or it is that the XSD needs to declare its type there.

Steps to reproduce the issue:

1. Use xgen to generate the code in goLang
2. Use the DPIXML_v1.08.xsd from https://www.oecd.org/tax/exchange-of-tax-information/DPI-DAC7-XML-Schema-and-User-Guide-v2.03.zip

Describe the results you received:
type AccountHolderType struct {
XMLName xml.Name xml:"AccountHolder_Type"
Individual *NameReportableSellerType xml:"Individual"
Organisation *OrganisationPartyType xml:"Organisation"
AcctHolderType *AcctHolderType xml:"AcctHolderType"
}
Describe the results you expected:
Not really sure what to expect, but code does not compile as there is no AcctHolderType type declared
Output of go version:

go version go1.16.15 linux/amd64

xgen version or commit ID:

xgen version: 0.1.0

Environment details (OS, physical, etc.):
Fedora35