Re: Including node in group when grouping key is null

Steve,

Gerrit offers an elegant solution provided your @type values are
controlled to avoid 'primary' in the data. :-)

More generally, you should find that group-by="@type" does not fail to
group nodes for which @type is empty. If you want to avoid those, you
need to select="author[exists(@type)". If you want to include them,
they'll be grouped with a key of '' (the empty string), along with
those that have @type=''. This is because the value returned by
@group-by is cast to a string, and string(()) is "".

Assuming @type will never be 'primary' (or whatever fallback value you
choose), Gerrit's solution succeeds in grouping authors with no @type
separately from authors with @type=''. Which is another reason to like
it.

Cheers, Wendell

Wendell Piez | http://www.wendellpiez.com
XML | XSLT | electronic publishing
Eat Your Vegetables
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On Thu, Jan 9, 2014 at 2:16 AM, Imsieke, Gerrit, le-tex
<gerrit.imsieke@xxxxxxxxx> wrote:
>
>
> On 09.01.2014 08:11, Steve Fogel wrote:
>>
>> <xsl:for-each-group select="author" group-by="@type">
>
>
> group-by="(@type, 'primary')[1]"