Example: Constrain a domain module using RNG

This section is non-normative.

In this scenario, a DITA architect wants to use only a subset of the elements defined in the highlighting domain. They want to use <b> and <i> but not any other of the elements in the domain. They want to integrate this constraint into the document-type shell for task.

Specifically, the DITA architect wants to redefine the content model in the following ways:

• Use <b> and <i>
• Remove <line-through>, <overline>, <sup>, <sup>, <tt>, and <u>

Note that when using RNG, domains can be constrained directly in the document-type shells.

1. They open the document-type shell for topic in an XML editor, and then they modify the "MODULE INCLUSIONS" division to exclude the elements that they do not want the implementation to use:

   <div>
     <a:documentation>MODULE INCLUSIONS</a:documentation>
     ...
     <include href="highlightDomain.rng">
       <define name="line-through.element">
         <notAllowed/>
       </define>
       <define name="overline.element">
         <notAllowed/>
       </define>
       <define name="sub.element">
         <notAllowed/>
       </define>
       <define name="sup.element">
         <notAllowed/>
       </define>
       <define name="tt.element">
         <notAllowed/>
       </define>
       <define name="u.element">
         <notAllowed/>
       </define>
     </include>
     ..  
   </div>

   Note (non-normative):

   The DITA architect made a choice as to where in the document-type shell they would implement the constraint. It can be placed either in the "Element-type configuration integration" or the "Module inclusions" section.
2. They make similar changes to all the other document-type shells in which they want to constrain the highlighting domain.