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Combining the DTDs of XML Languages

Module by: Sarah Coppin, Bill Wilson, Connexions. E-mail the authors

Summary: Explains how to include more than one XML language within the same document.


This module contains Connexions documentation which is out-of-date. The contents of this module are provided here for historical purposes only and should not be considered accurate for the current version of the Connexions website. Please visit the help page for up-to-date information about the Connexions website, including support for viewing and authoring content and the CNXML language. If you have any additional questions or cannot find the answer to your question, please contact and we will be happy to assist in any way we can.

Multiple XML languages can be combined in the same document. However, in order for these documents to be valid, they must have a Document Type Definition (DTD) that allows tags from one language to exist inside tags from another language. So if you wanted to include MathML in a CNXML document, you would need a DTD that allowed MathML to exist inside certain CNXML tags. Once that DTD existed, you would declare the DOCTYPE the same as normal. To actually use both languages you would need to use namespaces.

Example 1

For just CNXML, the doctype declaration is:

    <!DOCTYPE document PUBLIC "-//CNX//DTD CNXML 0.5//EN" 

For CNXML and MathML, the doctype declaration is:

    <!DOCTYPE document PUBLIC "-//CNX//DTD CNXML 0.5 plus MathML//EN" 

For CNXML and QML, the doctype declaration is:

    <!DOCTYPE document PUBLIC "-//CNX//DTD CNXML 0.5 plus QML//EN" 

For CNXML, QML, and MathML, the doctype declaration is:

    <!DOCTYPE document PUBLIC "-//CNX//DTD CNXML 0.5 plus
              MathML plus QML//EN" 

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