Application document defaults

- specifying default definitions in the application document.

<DSD:Default>
  <Context>
    <Element Name="form">
      <Attribute Name="action"/>
        <Sequence>
          <String Value="http://www.brics.dk/"/>
          <ZeroOrMore><AnyChar/></ZeroOrMore>
        </Sequence>
      </Attribute>
    </Element>
    <SomeElements/>
    <Element Name="input">
      <Attribute Name="type" Value="text"/>
    </Element>
  </Context>
  <DefaultAttribute Name="length" Value="30"/>
</DSD:Default>

(The length default previously defined is overridden for text type input elements inside form elements that have an action attribute whose value is a string starting with http://www.brics.dk/.)

An application document default

is applicable for the subtree rooted by its parent element, and
the inner-most application document default always overrides an outer one.