Counting Nodes

["Maltby, David G" <david.g.maltby@xxxxxxxx>]

I am working on producing RTF from content marked up with DTD which I do not
control.  It contains chunks such as:

<alert>
<text type="list:num">
  <text>List Item 1</text>
  <text type="list:alpha">
    <text>List Item a</text>
    <text>List Item b</text>
  </text>
  <text>List Item 2</text>
  <text>List Item 3</text>
</alert>

And so in RTF, the expectation is that it will look something like:

  1. List Item 1
    a. List Item a
    b. List Item b
  2. List Item 2
  3. List Item 3

Problem is you can not use (child-number) for counting the siblings because
when you get to the text node "List Item 2" then (child-number) will equal
3.  So I need another way to count the text siblings.  I came up with the
following procedure:

(define (text-node-cnt #!optional (cur-text-node (current-node)))
  (let loop ( (text-siblings (siblings cur-text-node)) (cnt 0) )
    (cond
      ((node-list-empty? (my-debug text-siblings))
        (cnt))
      ((node-list=? cur-text-node (node-list-first text-siblings))
        (+ cnt 1))
      ((has-attribute? (normalize "type") (node-list-first text-siblings))
        ;don't count it
        (loop (node-list-rest text-siblings) cnt))
      (else (loop (node-list-rest text-siblings) (+ cnt 1)))
    )
  )
)

Counting-wise this works great, the problem is when looking at the text
nodes containing "List Item 1", "List Item 2", or "List Item 3",
text-siblings starts out containing 13 nodes.  The procedure exits,
respectively, on the 1st, 8th, and 12th node.  My RTF looks like:

  1. List Item 1
    a. List Item a
    b. List Item b
  8. List Item 2
  12. List Item 3

For non-built-in procedures, I have used the procedure definitions found in
the DSSSL Documentation Library.  I can not for the life of me figure out
what group of 13 nodes (siblings) is returning to me.  Any ideas on how I
might debug this?  Is there a more elegant method I have not considered?


Best Regards,
David Maltby, IETM Team, Lockheed Martin Missile and Space
"Transforming instances conforming to one DTD 
into instances conforming to another DTD" (GKH)



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