- From: Martin McEvoy <martin@weborganics.co.uk>
- Date: Sun, 25 Oct 2009 10:23:58 +0000
- To: Ian Hickson <ian@hixie.ch>
- CC: public-html@w3.org
Hello Ian, Ian Hickson wrote: > On Sat, 24 Oct 2009, Martin McEvoy wrote: > >> Just some thoughts on the itemid and the itemref attributes >> >> I am unsure if itemid has any actual practical use (either that of I am >> misunderstanding something). >> >> Itemid is used as a global Identifier for an Item, its value must be >> valid absolute url, what I am unsure of is how to actually use this? >> here is how I am guessing it should be used. >> >> <div id="a" >> itemid="http://organization.com/#a" >> itemscope >> itemtype="http://microformats.org/profile/hcard"> >> <a itemprop="url fn org" href="http://organization.com/"> >> Example Oranization >> </a> >> </div> >> >> If this is correct then it seems a little like I am repeating data that >> already exists? itemid seems like it is just a long form version of the >> data available using id. I do see itemid as being useful for data that >> is *not* a url in the traditional sense, such as in the example that >> uses urn's >> > > The itemid attribute is only useful for vocabularies that use it. This > will mostly be vocabularies intended for use with RDF systems -- RDF > systems name lists of name-value pairs all the time. itemid="" in > Microdata is basically equivalent to about="" in RDFa. > That what I thought, a good example of how this may be useful is (in RDF terms) setting the subject of something anywhere on the web not just locally. I *can* use @id If I like (for locally defined items indeed I probably should ) its just @itemid is explicit. I had a short discussion off list that helped me confirm this. Thanks -- Martin McEvoy http://weborganics.co.uk/ Add to address book: http://transformr.co.uk/hcard/http://weborganics.co.uk/
Received on Sunday, 25 October 2009 10:24:26 UTC