[erlang-questions] xmerl and the xml namespace

[Karolis Petrauskas]

Hello erlangers,

I tried to parse XML document containing namespaced elements using
xmerl. The document contain xml:lang attributes and no declaration for
the xml prefix. The minimal example reproducing the error is bellow.

1> catch xmerl_scan:string("<a xml:lang='en_US'/>",
[{namespace_conformant, true}]).

{'EXIT',{fatal,{{namespace_prefix_not_declared,"xml"},
                {file,file_name_unknown},
                {line,1},
                {col,23}}}}

The same XML document is parsed successfully with {namespace_conformant, false}.

The XML specification (https://www.w3.org/TR/xml-names/#xmlReserved)
says, that the xml prefix can be used without declaration and must
refer to "http://www.w3.org/XML/1998/namespace".

Is this a bug in xmerl, or I misunderstand something?

Karolis