- From: Pat Hayes <phayes@ihmc.us>
- Date: Wed, 12 Oct 2005 18:21:27 -0500
- To: Bijan Parsia <bparsia@isr.umd.edu>
- Cc: public-ws-desc-comments@w3.org, "Henry S. Thompson" <ht@inf.ed.ac.uk>, public-ws-desc-comments-request@w3.org, Jonathan Marsh <jmarsh@microsoft.com>, Arthur Ryman <ryman@ca.ibm.com>, David Orchard <dorchard@bea.com>
>On Oct 12, 2005, at 6:03 PM, Pat Hayes wrote: >Arthur wrote: >>>That is not a problem in the XPointer framework since all the >>>parens are balanced. The WSDL URI have balanced parens. >> >>Sorry, I was being too brief. I realize the parens are balanced >>within the URI itself. But consider a parser which is trying to >>parse some notation like LISP or Common Logic Interchange Format, >>in which the parentheses are considered to be lexical break >>characters, and which contains embedded URIs as identifiers. Then a >>URI with an adjacent close parenthesis on the right will be quite >>common, as for example in a text such as >> >>(cl:text (ex:R ex:a)) > >This case, in a sense, doesn't matter since no sorta-qname >convention I know of permits it, even with a breaking space. If the >last character of a URI is not an ncname character, then you cannot >abbreviate it with a qname like construct. This is why RDF/XML >cannot serialize all legal RDF graphs. Sorry about the qnames. The point applies when full URIs are used, which is correct in CLIF in any case. I just got tired of typing. >>If URIs end with closing parentheses, then such a parser will be >>unable to disambiguate, say, the URI 'http://ex.badend/(foo)' from >>the concatenation of the URI 'http://ex.badend/(foo' and the >>closing parenthesis ')'. In practice, almost certainly the latter >>will be what is parsed, since the parser will not even seek the URI >>lexical form >[snip] >>Of course, there are ways around this: the URIs can be enclosed in >>protective lexical wrappings such as double quotes, for example, > >URIs always must be so protected (a la NTriples) because lots of >nasty characters (e.g., commas and quotes) can appear in a URI. Appearing inside is OK. Its appearing as the last character that hurts. Can a URI have a space as its terminating character? I surely hope not. But if so, are there any URIs actually in use that do this, anywhere on the planet? If not, then I don't really care what is technically legal: there is a de facto standard being used. >As I said, uris with funky trailing characters can't be abreviated >with Qnames anyway. Then Im just not interested in such URIs. So I wish we weren't landed with having to use one, for no good reason that I can determine. >> or users of these languages can be required to insert whitespace >>before a lexical-breaking parenthesis. But all such ways introduce >>artificiality and awkwardness into what is otherwise a very natural >>and widely used syntactic convention. > >One can turn this question around and ask why we are requiring >people to not use a composible, extensible standard (XPointer). Because not everyone who is using URIs is using XML, nor should they be required to. URIs have an importance that transcends XML syntax requirements. Seems to me that this whole discussion of XPointer is beside the point here. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 cell phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Wednesday, 12 October 2005 23:21:39 UTC