[xsl] Re: [saxon] Use of QName forcing declaration "Unused" namespaces

["Michael Kay mike@xxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Well, passing lexical QNames across interfaces is definitely a bad idea unless
you can be sure that both sides of the interface know the namespace context
(that is, the set of prefix-URI bindings). Without a namespace context, a
lexical QName is meaningless.

Michael Kay
Saxonica

> On 22 Jul 2020, at 01:23, Ihe Onwuka <ihe.onwuka@xxxxxxxxx> wrote:
>
>
>
> On Tue, Jul 21, 2020 at 7:48 PM Michael Kay <mike@xxxxxxxxxxxx
<mailto:mike@xxxxxxxxxxxx>> wrote:
> If the QNames are names of elements in the source document, then you
shouldn't be calling name() to get the lexical QName, and then calling
xs:QName to turn it back into an xs:QName value, because that loses
information (specifically, the namespace bindings that were in scope in the
source document). Instead, you should use the node-name() function to get the
name as an xs:QName value in the first place.
>
>
> You may have mistook $name for the name(), I am not calling the name()
function however that is useful information.
>
> I may have misunderstood what's going on here,
>
>   All that function does is get the local name from a parameter which is
either already an xs:QName or a string that will be cast to  an xs:QName.
There is not much to it beyond wanting to use XPath name functions rather than
string hacking on names.
>
> but I think this is the heart of the issue: if you're going to manipulate
QNames, then you need to get them out of lexical format and into structured
xs:QName format as early as possible, while the original namespace bindings
are still known.
>
> Michael Kay
> Saxonica
>
>> On 21 Jul 2020, at 15:02, Ihe Onwuka <ihe.onwuka@xxxxxxxxx
<mailto:ihe.onwuka@xxxxxxxxx>> wrote:
>>
>> Every element in my input doc is in one of  5 namespaces that I have
declared globally in the stylesheet. However the stylesheet as written never
explicitly references any of the 5 namespaces so  I would like to genericize
it by doing away with the namespace declarations.
>>
>> However if I remove any one of the namespaces I get this error.
>>
>> Error at char 79 in expression in xsl:sequence/@select on line 14 column
118 of ***.xsl:
>>   FONS0004  Namespace prefix {jx} has not been declared
>> at function local:localizedName on line 12 of ***.xsl:
>>
>> Here is the function local:localizedName which is designed to return  a
local name from a QName or a string.
>>
>> <xsl:function name="local:localizedName" as="xs:string?">
>>       <xsl:param name="name"/>
>>       <xsl:sequence select="local-name-from-QName(if ($name instance of
xs:QName) then $name else xs:QName($name))"/>
>>    </xsl:function>
>>
>> It seems that casting anything as QName mandates that the namespace prefix
in whatever is being cast must be declared , even if it's not explicitly
referenced.
>>
>> e.g xs:string(xs:QName($someName)) will fail if $someName contains 'ab:cde'
and you haven't declared the ab prefix anywhere (even if you don't otherwise
use it).
>>
>> In which case my goal is better achieved by eradicating the QNames and
resorting to string manipulation to extract the local part of the name.
>>
>> Comments, observations, corrections please.
>> _______________________________________________
>> saxon-help mailing list archived at http://saxon.markmail.org/
<http://saxon.markmail.org/>
>> saxon-help@xxxxxxxxxxxxxxxxxxxxx <mailto:saxon-help@xxxxxxxxxxxxxxxxxxxxx>
>> https://lists.sourceforge.net/lists/listinfo/saxon-help
<https://lists.sourceforge.net/lists/listinfo/saxon-help>