<para>substitute entities; possible values are 0 and 1</para>
<para>Note that although this flag disables entity substitution, it
does not prevent the parser from loading external entities;
- if entity substitution disabled, the
- document tree will contain an XML_ENTITY_REF_NODE node
+ when substitution of an external entity is disabled, the
+ entity will be represented in the document tree by a XML_ENTITY_REF_NODE node
whose subtree will be the content obtained by parsing the external resource;
of nesting is visible from the DOM
- <para>provide a custom external entity handler. Possible value is a subroutine reference.</para>
+ <para>Provide a custom external entity handler
+ to be used when expand_entities is set to 1.
+ Possible value is a subroutine reference.</para>
<para>The subroutine provided is called whenever
the parser needs to retrieve the content of an external entity.
It is called with two arguments: the system ID (URI) and the public ID.