Re: [xml] RelaxNG Question

[Daniel Veillard <veillard redhat com>]

On Tue, Dec 19, 2006 at 02:37:20PM -0800, Jason McKesson wrote:
> Because I haven't found a more appropriate venue for this question.
>
> In RelaxNG, let's say that you have 2 attributes. And you would like to 
> make a named pattern for them, such that it matches the attributes if 
> one of them or both of them are found. Is it possible to specify this 
> without saying:
>
> <choice>
>     <group>
>        <ref name="attrib1"/>
>        <ref name="attrib2"/>
>     </group>
>     <ref name="attrib1"/>
>     <ref name="attrib2"/>
> </choice>
>
>
> Because I have a schema now where I would want to have 3 (and in some 
> cases, possibly more) of these defined. That would require a lot of 
> extraneous manipulation.
>
> So, does RelaxNG have something for this?

  Hum, using the property that you can have a given attribute only once per node
inverting the group and using optional may work

  <group>
    <choice>
      attrib1
      attrib2
      ...
      attribn
    <choice>
    <optional>attrib1</optional>
    <optional>attrib2</optional>
    ...
    <optional>attribn</optional>
  </group>

should work and stay linear in expression complexity

Daniel

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