Is there a reason for no normative/informative reference to the XML specification within the document? XML 1.0 has several editions and there's also XML 1.1. The document is quite specific when it comes to XSD, XPATH, XSLT, and even XML-NAMES but not XML itself.
Jernej > -----Original Message----- > From: netmod [mailto:[email protected]] On Behalf Of Ladislav > Lhotka > Sent: Wednesday, August 17, 2016 2:50 PM > To: Martin Bjorklund <[email protected]> > Cc: [email protected] > Subject: Re: [netmod] YANG 1.1: XML naming restriction > > > > On 17 Aug 2016, at 14:34, Martin Bjorklund <[email protected]> wrote: > > > > Ladislav Lhotka <[email protected]> wrote: > >> > >>> On 01 Aug 2016, at 10:15, William Lupton <wlupton@broadband- > forum.org> > >>> wrote: > >>> > >>> But the errata at https://www.w3.org/XML/xml-V10-5e-errata say the > >>> following. There are also related changes to Section 2.6 (processing > >>> instructions) and Section 3 (logical structures). W. > >>> Section 2.3 Common Syntactic Constructs > >>> Delete the following paragraph: > >>> > >>> Names beginning with the string "xml", or with any string which would > >>> match (('X'|'x') ('M'|'m') ('L'|'l')), are reserved for > >>> standardization in this or future versions of this specification. > >> > >> Good catch! > > > > Indeed! > > > >> What this erratum means for YANG is that only "xml" prefix > >> needs to be forbidden. > > > > Actually, as Dale Worley pointed out, not even this is required, since > > the prefix is not required to be used in the XML encoding. > > > > I suggest we simply remove the line: > > > > ;; An identifier MUST NOT start with (('X'|'x') ('M'|'m') ('L'|'l')) > > I agree, good riddance. > > Lada > > > > > The document is now in AUTH48 so we can actually make this change. > > > > Juergen, and/or Benoit, do you think we can make this change to the > > document? If we do, we should also mention this in section 1.1. > > > > > > Eventually the type yang-identifier from RFC 6991 should be revised as > > well. > > > > > > /martin > > > > > > > >> > >> If it is still possible, it would IMO make a good sense to remove that > >> comment from the ABNF in 6020bis, and make this change in sec. 7.1.4: > >> > >> OLD > >> > >> A prefix is an identifier (see Section 6.2). > >> > >> NEW > >> > >> A prefix is an identifier (see Section 6.2), and it MUST NOT be the > >> string "xml". > >> > >> Lada > >> > >>> > >>>> On 1 Aug 2016, at 04:22, Andy Bierman <[email protected]> > wrote: > >>>> > >>>> > >>>> OK -- sorry -- must have read it wrong > >>>> > >>>> > >>>> Andy > >>>> > >>>> > >>>> > >>>> On Sun, Jul 31, 2016 at 6:57 PM, Dale R. Worley <[email protected]> > >>>> wrote: > >>>> Andy Bierman <[email protected]> writes: > >>>>> The YANG 1.1 ABNF says: > >>>>> > >>>>> ;; An identifier MUST NOT start with (('X'|'x') ('M'|'m') > ('L'|'l')) > >>>>> identifier = (ALPHA / "_") > >>>>> *(ALPHA / DIGIT / "_" / "-" / ".") > >>>>> > >>>>> > >>>>> There is no explanation given why. > >>>>> The same restriction was copied to RESTCONF, also without > explanation. > >>>>> Supposedly, XML does not allow identifiers to start with XML. > >>>>> > >>>>> Looks like this restriction only applies to the PITarget [17], not > >>>>> Name [5] > >>>>> https://www.w3.org/TR/REC-xml/#sec-pi > >>>>> > >>>>> We have been applying this restriction to element names > >>>>> but it only applies to processing instructions. > >>>>> > >>>>> IMO it should be removed. > >>>>> It confuses people when they get an error for naming a data node > >>>>> with a string that matches. > >>>> > >>>> Eh? Looking at "Extensible Markup Lanuage (XML) 1.0 (Fifth > Edition)", > >>>> section 3.1 (http://www.w3.org/TR/xml/#sec-starttags) says that the > >>>> element name of a start in end tag is a "Name". Looking at section > >>>> 2.3 > >>>> (http://www.w3.org/TR/xml/#sec-common-syn), I see > >>>> > >>>> Names beginning with the string "xml", or with any string which > >>>> would match (('X'|'x') ('M'|'m') ('L'|'l')), are reserved for > >>>> standardization in this or future versions of this specification. > >>>> > >>>> And since Yang data node names can appear as XML element names, > Yang > >>>> has > >>>> to forbid node names that start with "XML". > >>>> > >>>> Dale > >>>> > >>>> _______________________________________________ > >>>> netmod mailing list > >>>> [email protected] > >>>> https://www.ietf.org/mailman/listinfo/netmod > >>> > >>> _______________________________________________ > >>> netmod mailing list > >>> [email protected] > >>> https://www.ietf.org/mailman/listinfo/netmod > >> > >> -- > >> Ladislav Lhotka, CZ.NIC Labs > >> PGP Key ID: E74E8C0C > >> > >> > >> > >> > >> _______________________________________________ > >> netmod mailing list > >> [email protected] > >> https://www.ietf.org/mailman/listinfo/netmod > > -- > Ladislav Lhotka, CZ.NIC Labs > PGP Key ID: E74E8C0C > > > > > _______________________________________________ > netmod mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/netmod _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
