Conditional Sections |
The conditional section markup provides support for conditionally including and excluding content at parse time within an XML document's external subset. Conditional sections are not allowed within a document's internal subset. The following example illustrates a likely application of conditional sections:
    <!ENTITY % debug 'IGNORE' >
    <!ENTITY % release 'INCLUDE' >

    <!ELEMENT addend (#PCDATA)>
    <!ELEMENT result (#PCDATA)>

    <![%debug;[
    <!ELEMENT sum (addend+, result)>
    ]]>
    <![%release;[
    <!ELEMENT sum (result)>
    ]]>