Tom,

> I thought you already had, i.e. Elements in two documents refer to the same
> item (i.e. equivalent) if they
> 
> a) have the same element name
> b) have the same number and values of attributes
> c) the parents are equivalent (by the same rules)
> 
> NB c) doesn't need to use ancestors because the parents can only be
> equivalent if their parents are etc. etc.

thinking about it I came to the conclusion that it's not that simple.
How would you like to see the following documents merged?

<a>
  <b>First</b>
  <b>Second</b>
</a>

and

<a>
  <b>Third</b>
</a>

My transformation gives
<a>
  <b>FirstThird</b>
  <b>Second</b>
</a>

According to your suggestion, the following would also be ok:
<a>
  <b>First</b>
  <b>SecondThird</b>
</a>

My rules must include
d) if they are at the same position (relative to their parent node)

Cheers,
Oliver


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|  ob|do        Dipl.Inf. Oliver Becker                             |
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|  op|qo        WWW:    http://www.informatik.hu-berlin.de/~obecker |
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