xml vs map in Go

gistfile1.txt

package main

import "fmt"
import "encoding/xml"

// IdentityDkimAttributes is undocumented.
type IdentityDkimAttributes struct {
	DkimEnabled            bool     `query:"DkimEnabled" xml:"DkimEnabled"`
	DkimTokens             []string `query:"DkimTokens.member" xml:"DkimTokens>member"`
	DkimVerificationStatus string   `query:"DkimVerificationStatus" xml:"DkimVerificationStatus"`
}

type IdentityDkimAttributesMap map[string]IdentityDkimAttributes

func (m *IdentityDkimAttributesMap) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
	(*m) = make(IdentityDkimAttributesMap)
	v := struct {
		Entry []struct{
			Key   string                 `xml:"key"`
			Value IdentityDkimAttributes `xml:"value"`
		} `xml:"entry"`
	}{}

	if err := d.DecodeElement(&v, &start); err != nil {
		return err
	}

	for _, e := range v.Entry {
		(*m)[e.Key] = e.Value
	}

	return nil
}

// GetIdentityDkimAttributesResponse is undocumented.
type GetIdentityDkimAttributesResponse struct {
	DkimAttributes IdentityDkimAttributesMap `query:"DkimAttributes" xml:"GetIdentityDkimAttributesResult>DkimAttributes"`
}

var x = []byte(`<?xml version="1.0"?>
<GetIdentityDkimAttributesResponse xmlns="http://ses.amazonaws.com/doc/2010-12-01/">
<GetIdentityDkimAttributesResult>
<DkimAttributes>
<entry>
<key>amazon.com</key>
<value>
<DkimEnabled>true</DkimEnabled>
<DkimVerificationStatus>Success</DkimVerificationStatus>
<DkimTokens>
<member>vvjuipp74whm76gqoni7qmwwn4w4qusjiainivf6f</member>
<member>3frqe7jn4obpuxjpwpolz6ipb3k5nvt2nhjpik2oy</member>
<member>wrqplteh7oodxnad7hsl4mixg2uavzneazxv5sxi2</member>
</DkimTokens>
</value>
</entry>
<entry>
<key>amazon.co.jp</key>
<value>
<DkimEnabled>true</DkimEnabled>
<DkimVerificationStatus>Success</DkimVerificationStatus>
<DkimTokens>
<member>vvjuipp74whm76gqoni7qmwwn4w4qusjiainivf6f</member>
<member>3frqe7jn4obpuxjpwpolz6ipb3k5nvt2nhjpik2oy</member>
<member>wrqplteh7oodxnad7hsl4mixg2uavzneazxv5sxi2</member>
</DkimTokens>
</value>
</entry>
</DkimAttributes>
</GetIdentityDkimAttributesResult>
<ResponseMetadata>
<RequestId>bb5a105d-c468-11e1-82eb-dff885ccc06a</RequestId>
</ResponseMetadata>
</GetIdentityDkimAttributesResponse>
`)

var m = []byte(`<?xml version="1.0"?>
<DkimAttributes>
<entry>
<key>amazon.com</key>
<value>
<DkimEnabled>true</DkimEnabled>
<DkimVerificationStatus>Success</DkimVerificationStatus>
<DkimTokens>
<member>vvjuipp74whm76gqoni7qmwwn4w4qusjiainivf6f</member>
<member>3frqe7jn4obpuxjpwpolz6ipb3k5nvt2nhjpik2oy</member>
<member>wrqplteh7oodxnad7hsl4mixg2uavzneazxv5sxi2</member>
</DkimTokens>
</value>
</entry>
<entry>
<key>amazon.co.jp</key>
<value>
<DkimEnabled>true</DkimEnabled>
<DkimVerificationStatus>Success</DkimVerificationStatus>
<DkimTokens>
<member>vvjuipp74whm76gqoni7qmwwn4w4qusjiainivf6f</member>
<member>3frqe7jn4obpuxjpwpolz6ipb3k5nvt2nhjpik2oy</member>
<member>wrqplteh7oodxnad7hsl4mixg2uavzneazxv5sxi2</member>
</DkimTokens>
</value>
</entry>
</DkimAttributes>
`)

func main() {
	{
		e := GetIdentityDkimAttributesResponse{}
		xml.Unmarshal(x, &e)
		fmt.Println(e)
	}

	{
		e := IdentityDkimAttributesMap{}
		xml.Unmarshal(m, &e)
		fmt.Println(e)
	}
}

var _ xml.Unmarshaler = &IdentityDkimAttributesMap{}