code review 12919043: encoding/xml: add, support Marshaler interface

encoding/xml: add, support Marshaler interface

See golang.org/s/go12xml for design.

Repeat of CL 12603044, which was submitted accidentally
and then rolled back.

Fixes issue 2771.
Fixes issue 4169.
Fixes issue 5975.
Fixes issue 6125.

[rsc, 2013-08-14 04:22:13]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://code.google.com/p/go/

[rsc, 2013-08-14 18:58:10]

The previous copy of this CL was LGTM'ed, so now that the right prereqs are
checked in, submitting this again.

[rsc, 2013-08-14 18:58:31]

*** Submitted as https://code.google.com/p/go/source/detail?r=7b9e2c29bf14 ***

encoding/xml: add, support Marshaler interface

See golang.org/s/go12xml for design.

Repeat of CL 12603044, which was submitted accidentally
and then rolled back.

Fixes issue 2771.
Fixes issue 4169.
Fixes issue 5975.
Fixes issue 6125.

R=golang-dev
CC=golang-dev
https://codereview.appspot.com/12919043

[shiv, 2013-08-24 11:28:50]

On 2013/08/14 18:58:31, rsc wrote:
<snip>
> Fixes issue 2771.
> Fixes issue 4169.
> Fixes issue 5975.
> Fixes issue 6125.
> 
<snip>

rsc, issue 5975 does not seem to be closed. Can you please comment?

As updated in https://code.google.com/p/go/issues/detail?id=5975,

>>>
If I provide the input as:

    <ns1:mytag xmlns:ns1="http://www.mynsdefs.org/nsdefs-here-ns1">
	<ns2:Name>xyz</ns2:Name>
    </ns1:mytag>

Output is:
    <mytag xmlns="http://www.mynsdefs.org/nsdefs-here-ns1">
        <Name>xyz</Name>
    </mytag>

Isn't this an issue?
ns1 & ns2 are gone in the output. play link: http://play.golang.org/p/7V9gprqiG-
<<<

[rsc, 2013-09-06 19:52:11]

If you want to reproduce the namespace value for Name, you need to record
it. http://play.golang.org/p/RTU3Kk9fLq