Re: 7.1 and 7.3 are as bad as XML Schema

[Kohsuke KAWAGUCHI <kohsuke.kawaguchi@eng.sun.com>]

I think I can say that I have a fair degree of understanding.


> If you claim that you understand 7.4, please give non-trivial examples of 
> key-ambiguous grammars.  > each member

Well, here is my take:

<start>
  <element name="root">
  <!-- two versions of para -->
    
    <element name="para">
      <!-- title as an element -->
      <element name="title">
        <text/>
      </element>
      <attribute name="foo">
        <list><zeroOrMore>
          <key name="symSpace">
            <data type="NMTOKEN"/>
          </key>
        </zeroOrMore></list>
      </attribute>
      ...
    </element>
    
    <element name="para">
      <!-- title as an attribute -->
      <attribute name="title" />
      <attribute name="foo">
        <key name="symSpace">
          <data type="NMTOKEN"/>
        </key>
      </attribute>
      ...
    </element>
  </choice>
</element>


You can always tell that which "para" is used. So you can always tell
that @foo is a list or not. But nevertheless this grammar is ambiguous.


regards,
--
Kohsuke KAWAGUCHI                          +1 650 786 0721
Sun Microsystems                   kohsuke.kawaguchi@sun.com