- From: Martin Duerst <duerst@w3.org>
- Date: Fri, 06 Dec 2002 07:29:18 +0900
- To: "jeremy carroll" <jjc@hpl.hp.com>, <www-tag@w3.org>
- Cc: Michel Suignard <michelsu@microsoft.com>, www-international@w3.org
Hello Jeremy, The main reason that spaces,... got included in IRIs was XPointer. Please note that "	" and " " are not legal IRIs, at least not according to the current IRI spec. And we have definitely no plan to add them. Regards, Martin. At 12:09 02/12/04 +0100, jeremy carroll wrote: >Julian Reschke wrote: > > This issue could > > *probably* solved by explicitly forbidding those ASCII characters in > > namespace names which have been forbidden in URIs as well > >I am increasingly convinced by the case Julian has been making that IRIs >should treat 7-bit ascii characters according to the URI specs. > >I had some test data connected with the treatment of the 'excluded' >characters. > >That all of the following are relative IRIs is, at least a little, >surprising: >(I use XML attribute notation, CDATA attribute value normalization) > >"<b>b" >"	" >" " >" " >"{" >"\" > >These characters are excluded in RFC 2396 because other systems use them. >While in XML this perhaps is not an issue, with any interoperation between >XML and other systems, it becomes difficult. > >An example that came up yesterday was mapping such relative IRIs out of >RDF/XML into an RDF graph (in memory) and then out into N3. >The N3 grammar expects to be able to use < and > as delimiters, as indicated >in RFC 2396. > >I found myself unable to defend this treatment to a colleague whose N3 >parser was having difficulty. > >Is there a case as to why IRIs differ from URIs on the ascii subset? >Or is it, essentially, an historical accident? > >Jeremy Carroll > >Appendix - Sample normative text: >[[ >The characters to be escaped are the contol characters #x0 to #x1F and #x7F >(most of which cannot appear in XML), space #x20, the delimiters '<' #x3C, >'>' #x3E and '"' #x22, the unwise characters '{' #x7B, '}' #x7D, '|' #x7C, >'\' #x5C, '^' #x5E and '`' #x60, as well as all characters above #x7F. >]] >http://www.w3.org/XML/xml-V10-2e-errata#E26 > >equivalently >[[ >the disallowed characters include all non-ASCII characters, plus the >excluded characters listed in Section 2.4 of [IETF RFC 2396], except for the >number sign (#) and percent sign (%) and the square bracket characters >re-allowed in [IETF RFC 2732]. Disallowed characters must be escaped >]] >http://www.w3.org/TR/xlink/#link-locators > >-- alternative text, URI compatible > >[[ >The characters to be escaped are all characters above #x80. >]] >or >[[ >the disallowed characters are all non-ASCII characters. Disallowed >characters must be escaped >]] > > > > > > > >
Received on Thursday, 5 December 2002 18:03:14 UTC