Re: Constructing multi-level lists - any better than

Thanks a lot for your input to a (kind-of) solved problem. I really
appreciate the support from more experienced programmers.

Geert's solution is along what in the FAQs is called "tree-walking".
I like that it is shorter than mine and does not need to use
priority. It is easier to understand/explain and can be extended to
the case I have on my desk. And I thought xsl:key is always the
coolest solution... you still have to think 'around the corner' with
this tree-walker.

Andrew: I was longing for a solution with some XSLT2 but I have a
problem with group-starting-with="*[self::p]", because the p elements
are just placeholders for any other element that does not belong to a
list and may appear any number of times. So the source XML is a
mixture of some non-list elements followed by some list elements
followed by some non-list elements... The source may even begin with
some list elements. Perhaps my example was too much stripped down.
This would have illustrated it better:

<?xml version="1.0" encoding="UTF-8"?>
<levels>
<li1>1</li1>
<li2>2.1</li2>
<li2>2.2</li2>
<li1>3</li1>
<li1>4</li1>
<p/>
<any/>
<li1>5</li1>
<li1>6</li1>
<li2>7.1</li2>
<li2>7.2</li2>
<any/>
<p/>
<li2>8.1</li2>
<li2>8.2</li2>
<li1>9</li1>
<li1>10</li1>
<any/>
<p/>
</levels>

Abel, thanks for dealing with the more general issue of multiple
levels. Your way of doing it seems like a hybrid of for-each-group
and the tree-walker. It seems to me it uses the group only to get the
first element and then walks the tree, then creates a sub-group...
Oh, I have to look more into this, especially into the the use of
xsl:function which helps to clean-up the code (which I need, because
the elements I have are a bit more complicated than in my example).

For today, I'll go with Geert's approach, enhanced by some
xsl:function to make the match attributes in my real world case more
readable.

Thanks again for shifting my mind into XSL more than  I could have
achieved on my own!