> still I don't know how to get the node position and put it into a
> variable

it's not clear why you need a variable at all, partly because whatever
 mail client you are using appears to be stripping all your examples
your initial posting looked like

  The output would look something like this:
  ...
  ......

from  

> I generate an ID based on the depth and position of the XML tree

you may just want something like <tr id="id{count(ancestor::*)}" or use
the built in ID generator
<tr id="{generate-id()"

David

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