More Complex Example of Aggregating Modifiers in DTDs

Following is a more complicated example. Suppose you want book elements to include

  • Exactly one title
  • Either an author or an editor, but it is okay if neither appear
  • Zero or more paragraphs

To accomplish this, you would perform steps that generate the following tree representation:

book
               

              
Sequence
                   
title
                   
Optional
                   
	Choice
                   
		author
                   
		editor
                   
Zero or More
                   
	paragraph
                   

                

In the Text view of the DTD, the definition for the book element is as follows:

<!ELEMENT book (title, (author|editor)?, paragraph*)>
               

            

Internet & eBusiness

Internet & eBusiness

Chemical Companies That Use Stylus Studio

When working in a lab it's always important to have the right ingredients. That's why top chemical companies use Stylus Studio 2006 to create the ultimate experiments. See which of these top chemical companies are using Stylus Studio today!

Support for DataDirect SequeLink

Learn about Stylus Studio's support for DataDirect SequeLink, an end-to-end database middleware solution that provides a universal thin client for ODBC, JDBC, ADO or .NET, providing flexibility for both client- and server-based deployments.

Learn SQL/XML

Learn how to access and update relational databases using industry-standard SQL/XML technologies along with Stylus Studio's DB-to-XML editor and File Explorer technologies.

Stylus Most Wanted

 
Free Stylus Studio XML Training:
W3C Member