Subject: Re: [xsl] are all strings in a sequence valid potential QNames From: Liam R E Quin <liam@xxxxxx> Date: Thu, 04 Feb 2010 21:40:48 -0500 |
On Thu, 2010-02-04 at 21:48 +1030, Justin Johansson wrote: > With respect, Liam, I find your comments a tad dismissive of the problem. I'm sorry, I do not mean to sound dismissive. [...] > What the issue is about is the question of validating source data > in (to the XML parser) and writing valid result data upon serialization. > As many others have pointed out, in the absence of an explicit XML version > identifier it's pretty difficult to unambiguously determine whether you > are validating an XML 1.0 source document against pre- or post- 1.0 5th > edition. As with any spec with errata, or with multiple editions, one should normally implement the most recent. The most important thing is that the 5e names are a strict superset of 4e names: that is, ever document that is well-formed according to 4e remains well-formed according to 5e, and similarly for validity. So for reading, if you accept 5e you should be fine, and for writing, the only time it makes a difference is if there are names that use characters that were not allowed in earlier editions - 5e says that you can serialize them in that case, and the only alternative is to go wrong, since there's no escaping mechanism [1]. > If there is a version of XML that would be a pleasure to support that > would have to be XML 1.0.5. Is it really too late? What would you like XML 1.0.5 to be? (although that's for sure in danger of getting off-topic...) Recall that (unfortunately) many XML 1.0 processors will in practice refuse to accept an input document with a version declaration that's other than "1.0", so a 1.0.5 is in no better position in that regard than XML 1.1. Originally I went to the XML Core Working Group and suggested that they (1) relax the rule making it a fatal error if the version in the version declaration is not 1.0 (which they did) (2) produce an XML 1.2 that brought XML up to date with Unicode. and (3) consider deprecating XML 1.1. But they felt - justifiably - that an XML 1.2 had little or not better chance to succeed than 1.1, even with (1) in place, and conversations with some of the implementors seemed to bear this out. For my part, I don't think we should try a whole lot more tinkering with XML, or at least with XML 1.x, and I don't think the world is ready for an XML 2.x. But, I am still very interested in hearing from others in this regard, and yes, I was aware of the blogs. Sometimes what's practical to get done isn't what you'd like to see happen, and for me at least, 5e was certainly one of those cases, although I know I'm also paying a penalty for mistakes I (and others) made with XML 1.1. Liam PS: [1] - I did consider that if 5e did not get adoption, we could move to using "unichar", in which (as I propose), the lowercase letter "u" is followed by one or more hex digits, up to a q, so that u38q would work a bit like &, except of course that it would be allowed in names. A literal "u" in a name would have to be replaced by u75q. -- Liam Quin - XML Activity Lead, W3C, http://www.w3.org/People/Quin/ Pictures from old books: http://fromoldbooks.org/ Ankh: irc.sorcery.net irc.gnome.org www.advogato.org
Current Thread |
---|
|
<- Previous | Index | Next -> |
---|---|---|
Re: [xsl] are all strings in a sequ, List Owner | Thread | Re: [xsl] are all strings in a sequ, Justin Johansson |
RE: [xsl] How to gracefully check i, Houghton,Andrew | Date | Re: [xsl] are all strings in a sequ, ac |
Month |