The namespace axis is deprecated in Xslt from v2 and implementations do not need to support it.
There are now functions to enquire about the in-scope namespaces. But the important thing is that the namespaces axis was not like attributes: it gives you the in-scope namespaces not the namespaces defined on the current element.
I can see three different possible efinitions of 'empty' for namespaces.
* If you want to know 'are there any in-scope namespaces defined for this node'? you use the in-scope namespace function.
* If you want to know 'is this element in any namespace?' I think you can use the namespace accessor function.
* If you want to know 'have any namespaces been declared on this element?' I think you check if the in-scope namespaces of the current element are the same as its parents using functions. (That will miss duplicate declarations, so it is not perfect.)
When I do XPath training, I just leave out any details of the old namespace axis and say 'dont use it, it had problems, it varies by implementation, they deprecated it.'
It isone example where fidelity source-to-source conversions need more info than the xsd data model (or the xml info set provides.) The other example is that we don't know whether an attribute got its value from being specified or implied from the DTD. I think that is because a lot of the technocrats came from the open source world, which basically meant that they used SGMLS: Omnimark provided a test WHEN ATTRIBUTE X IS SPECIFIED that was really useful. XML infoset and xpath data models allow regeneration of the parsed xml not tag-level transformations.
Regards
Rick
Hi Roger,<quote>Okay, I added namespace::* to the XPath that David provided, to take into account namespaces. Here is the new XPath: empty((node(),@*,namespace::*)
)
Here are the results I got from running my XSLT program using the new XPath:
Is empty?
<B/>
true
<B></B>
true
<B>&null;</B>
true
<B> </B>
false
<B><!-- Hello, world --></B>
false
<B><bad/></B>
false
<B>99</B>
false
<B x="10"/>
false
<B xmlns:b="test"/>
false
Perfect!
</quote>I am wondering what combination of parser/xslt-processor you were using...Because the XPath expression:empty((node(),@*,namespace::*)) should produce false in all cases.The reason? every element has at least two namespace nodes -- the xml namespace and the xml-namespace namespace nodes.And, indeed, this is exactly what I am getting using Saxon 9.1.A correct XPath expression is this:empty( (
node(),
@*,
namespace::*[not(name() = ('xml', 'xmlns'))]
)
)Here I assume that the XML parser will raise an error in case the reserved prefixes "xml" and "xmlns" are rebound to other namespace URIs.Cheers,DimitreOn Sat, Sep 24, 2016 at 2:02 PM, Costello, Roger L. <costello@mitre.org> wrote:David Carlisle wrote:
Also you are classing attributes as non-empty content
but not namespace nodes so<B foo=""/> is non empty but
<B xmlns:x="data:,hello"></B> is emptyAh, good catch David.
Okay, I added namespace::* to the XPath that David provided, to take into account namespaces. Here is the new XPath: empty((node(),@*,namespace::*)
)
Here are the results I got from running my XSLT program using the new XPath:
Is empty?
<B/>
true
<B></B>
true
<B>&null;</B>
true
<B> </B>
false
<B><!-- Hello, world --></B>
false
<B><bad/></B>
false
<B>99</B>
false
<B x="10"/>
false
<B xmlns:b="test"/>
false
Perfect!
Those results are from running SAXON in Oxygen XML.
John and David pointed out I might get different results with another parser. Specifically, another parser might discard comments and the whitespace in <B> </B>. Such a parser would produce these results:
Is empty?
<B/>
true
<B></B>
true
<B>&null;</B>
true
<B> </B>
true
<B><!-- Hello, world --></B>
true
<B><bad/></B>
false
<B>99</B>
false
<B x="10"/>
false
<B xmlns:b="test"/>
false
Is there any way to write an XPath expression that always produces the results shown in the first table, regardless of which parser is used?
/Roger
--Cheers,Dimitre Novatchev--------------------------------------- Truly great madness cannot be achieved without significant intelligence.--------------------------------------- To invent, you need a good imagination and a pile of junk------------------------------------- Never fight an inanimate object------------------------------------- To avoid situations in which you might make mistakes may be thebiggest mistake of all------------------------------------ Quality means doing it right when no one is looking.------------------------------------- You've achieved success in your field when you don't know whether what you're doing is work or play------------------------------------- To achieve the impossible dream, try going to sleep.------------------------------------- Facts do not cease to exist because they are ignored.------------------------------------- Typing monkeys will write all Shakespeare's works in 200yrs.Will they write all patents, too? :)------------------------------------- Sanity is madness put to good use.------------------------------------- I finally figured out the only reason to be alive is to enjoy it.