Re: [xsl] things about grouping

[Geert Bormans <geert@xxxxxxxxxxxxxxxxxxx>]

> 2. If your group by patttern evaluates to  an empty element
> current-grouping-key() will yield nothing. However one may (as I did)
> want to get at the attributes of such an element but this is not
> possible.

current-grouping-key() will not yield "nothing"
it will yield the empty string (if a sequence of empty strings, 
duplicates are removed)
All the element that have a grouping key = empty string, will be in 
the group with current-grouping-key() = ''
and you will have access to their attributes without a problem.
You will have to expand on this to explain what exactly your problem 
is, so we can help you get around this


> 3. If you group-starting-with it's weird to then see things not
> encompassed by the starting-with expression appear as a group because
> they precede the first occurrence of the starting-with expression.
> While this works as specified  because for-each-group is a total
> function over the population it does result in a mismatch between the
> grammatical semantic and the exhibited behaviour, or to put it another
> way it does what it says in the spec but  doesn't do what it says on
> the tin.

Thank God a programming language does as per specification ;-)
If you don't want that preceding group simply get rid of it using some test
For me the semantics is right...
all nodes selected are grouped without throwing away selected nodes

I think for both 2. and 3. the answer in 1. will help you understand 
the mechanism

cheers

Geert