Martin Holmes wrote:
>
> Where seg/@type = 'type_01', then seg/@subtype must be one of 'a', 'b' 
> or 'c';
>
> Where seg/@type = 'type_02', then seg/@subtype must be one of 'x', 
> 'y', or 'z'.
>
> Is this possible, and if so, how would I encode this into an ODD file?
>
You cannot model dependencies between attributes in RELAXNG, so you'd have
to write Schematron rules (allowed inside <content>). Off the top of my 
head:

<s:pattern name="segTypes">
  <s:rule context="tei:seg">
    <s:assert
    test="@type='TYPE_01'
          and not(@subtype='a' or 'b' or 'c')">
      Type TYPE_01 is associated with subtypes a, b, or c only
    </s:assert>
    <s:assert
    test="@type='TYPE_02'
          and not(@subtype='x' or 'y' or 'z')">
      Type TYPE_01 is associated with subtypes x, y, or z only
    </s:assert>
  </s:rule>
</s:pattern>

but you may be able to express more elegantly.

-- 
Sebastian Rahtz      

Information Manager, Oxford University Computing Services
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