Specify whether to show the attribute default value.
<p>
The default value is provided by the <code>'default'</code> attribute
specified in the XSD element of the attribute declaration.
For example:
<dl><dd>
<code>&lt;xs:attribute name="abstract" type="xs:boolean" <b>default="false"</b>/&gt;</code>
</dd></dl>

When the attribute is defined by reference to a global attribute, its default value may be specified both
in the local reference component (which is being documented here)
and in the global (referenced) attribute component. In that case, the actual default value will be looked for,
first, in the reference component and, then, in the global one.