Including other DTDs

["Remco de Boer" <deboer@zoorobotics.com>]

Hi all,

 

I'm currently investigating the MatML DTD (v2.0) that can be found at http://matml.nist.gov/

 

This DTD specifies the use of two other DTDs; the Virtual Hyperglossary (VHG) and Scalable Vector Graphics (SVG) DTD. The syntax it uses to include these DTDs is as follows:

 

<!ENTITY % VHG SYSTEM "http://www.vhg.org.uk/dtd/vhgdtd.html">
<!ELEMENT Terms (%VHG;)>
<!ATTLIST Terms %xmlns;>

 

<!ENTITY % SVG PUBLIC "-//W3C//DTD SVG 20001102//EN"
"http://www.w3.org/TR/2000/CR-SVG-20001102/DTD/svg-20001102.dtd">
<!ELEMENT Graphs (%SVG;)>
<!ATTLIST Graphs %xmlns;>

with the xmlns parameter entity defined as

 

<!ENTITY % xmlns "xmlns CDATA #IMPLIED">

 

When I try to view an example XML document with Internet Explorer, I get an error (A name was started with an invalid character). After commenting out the above mentioned Terms and Graphs elements (that are not used within the example document) all goes well.

 

This has left me to wonder: is this a legal way to include elements from other DTDs in a DTD, and is Internet Explorer/MSXML at fault? If so, what parser/validator can deal with this situation? If not so, how should it be accomplished instead?

 

Kind regards,

Remco de Boer