- From: Shane McCarron <shane@aptest.com>
- Date: Tue, 17 Nov 2009 07:59:12 -0600
- To: Ivan Herman <ivan@w3.org>, Niklas Lindström <lindstream@gmail.com>
- Cc: Mark Birbeck <mark.birbeck@webbackplane.com>, Ben Adida <ben@adida.net>, RDFa <public-rdf-in-xhtml-tf@w3.org>
I suppose a 'should not' admonition would be harmless. Ivan Herman <ivan@w3.org> wrote: >That is probably correct. It is also a very bad authoring practice... > >In more general terms, one could declare a number of strings as being >off-limit for CURIE-s. But I am not sure it is worth the trouble in >terms of usage. > >Ivan > > > >Niklas Lindström wrote: >> Another point though. Isn't there a problem if prefixes are declared >> for existing protocols? >> >> When prefixes are declared for e.g.: >> >> xmlns:http="http://www.w3.org/2006/http#" >> xmlns:tag="http://example.org/tagging#" >> >> With the proposed rules ("unsafe CURIE or URI"), wouldn't these: >> >> about="http://example.org/me" >> resource="tag:example.org,2009:item:1" >> >> be resolved against those prefixes (instead of as-is)? >> >> Best regards, >> Niklas >> >> >> 2009/11/16 Niklas Lindström <lindstream@gmail.com>: >>> Ah, but indeed! Good elephant-hunting Mark! ;) It's quite comforting >>> that RFC 3986 is so precise about these things. >>> >>> (I should have known that -- I now recall reading that very same rule >>> a couple of months ago when investigating the legality of non-escaped >>> colons in URI:s. Only remembered half of it apparently.) >>> >>> Best regards, >>> Niklas >>> >>> >>> 2009/11/16 Ivan Herman <ivan@w3.org>: >>>> Pfew...:-) >>>> >>>> Ivan >>>> >>>> P.S. Mark-the-elephant-hunter:-) >>>> >>>> Mark Birbeck wrote: >>>>> Hi Ivan/Niklas, >>>>> >>>>> 2009/11/16 Ivan Herman <ivan@w3.org>: >>>>>> Hi Niklas, >>>>>> >>>>>> Niklas Lindström wrote: >>>>>>>> So is there an elephant?:-) >>>>>>> I haven't followed this discussion to closely, so I want to check if >>>>>>> this the following is considered: >>>>>>> >>>>>>> This usage will "muddle the waters" in cases when the relative URI:s >>>>>>> contain colon, and there is a prefix with the same name as the leading >>>>>>> part before that, right? Concrete (but contrieved) example: >>>>>>> >>>>>>> Given: >>>>>>> - base URI: <http://en.wikipedia.org/wiki/> >>>>>>> - prefix Talk: <http://example.org/schema/talk#> >>>>>>> >>>>>>> When: >>>>>>> @resource="Talk:Linked_Data" >>>>>>> >>>>>>> Then: >>>>>>> - URI becomes < http://example.org/schema/talk#Linked_Data>, >>>>>>> instead of <http://en.wikipedia.org/wiki/Talk:Linked_Data>, which is >>>>>>> might be expected? >>>>>>> >>>>>> Hm. You may found the elephant:-) >>>>>> >>>>>> Yes, in this case one would indeed get the example.org URI. >>>>>> >>>>>> The question is: is this use case so strong as to nullify the advantages >>>>>> of using CURIE-s in @about? Indeed, wikipedia uses such URI-s with ':' >>>>>> quite a lot but the user can of course put full URI-s into the value of >>>>>> @about... >>>>>> >>>>>> Thanks! >>>>> >>>>> Whoah...slow down. :) >>>>> >>>>> "Talk:Linked_Data" is not a relative path! >>>>> >>>>> Forget prefixes, CURIEs, whatever...even if those things did not >>>>> exist, how would a URI processor know whether "Talk:" is a scheme or >>>>> just part of a relative path? >>>>> >>>>> RFC 3986 [1] addresses this in the following way: >>>>> >>>>> A path segment that contains a colon character (e.g., "this:that") >>>>> cannot be used as the >>>>> first segment of a relative-path reference, as it would be mistaken >>>>> for a scheme name. >>>>> Such a segment must be preceded by a dot-segment (e.g., >>>>> "./this:that") to make a >>>>> relative-path reference. >>>>> >>>>> So, if people are using relative paths that contain colons, in the >>>>> wild, then there's a problem, and that problem is completely >>>>> independent of RDFa. >>>>> >>>>> Regards, >>>>> >>>>> Mark >>>>> >>>>> [1] <http://www.ietf.org/rfc/rfc3986.txt> >>>>> >>>>> -- >>>>> Mark Birbeck, webBackplane >>>>> >>>>> mark.birbeck@webBackplane.com >>>>> >>>>> http://webBackplane.com/mark-birbeck >>>>> >>>>> webBackplane is a trading name of Backplane Ltd. (company number >>>>> 05972288, registered office: 2nd Floor, 69/85 Tabernacle Street, >>>>> London, EC2A 4RR) >>>> -- >>>> >>>> Ivan Herman, W3C Semantic Web Activity Lead >>>> Home: http://www.w3.org/People/Ivan/ >>>> mobile: +31-641044153 >>>> PGP Key: http://www.ivan-herman.net/pgpkey.html >>>> FOAF: http://www.ivan-herman.net/foaf.rdf >>>> >>>> > >-- > >Ivan Herman, W3C Semantic Web Activity Lead >Home: http://www.w3.org/People/Ivan/ >mobile: +31-641044153 >PGP Key: http://www.ivan-herman.net/pgpkey.html >FOAF: http://www.ivan-herman.net/foaf.rdf >
Received on Tuesday, 17 November 2009 13:59:48 UTC