Re: Yahoo's RDF vocabularies

Peter Mika wrote:
> I thought I would just address one specific point:
> 
>> Yahoo defines both this:
>>     
>> media:Image, media:Audio, media:Video
>>
>> and this:
>>
>> media:medium - The type of object: image | audio | video | document |
>> executable.
>>
>> What's the point of having both a 'medium' property and classes that
>> define the medium? media:medium shouldn't exist at all - use one or the
>> other, not both. Using both is confusing and will inevitably lead to
>> more pain for Yahoo down the line when you have to look at not only
>> @typeof information, but also medium information.
> 
> We need this to simplify the life of publishers who want a single line
> to indicate that there is a video attached to the page:
> 
> <link rel="media:video" href="...">

That's a good goal to have, but think about the triple that you're creating:

<mypage.html>
   <ymedia:medium>
      <puppies.swf> .

That doesn't provide a single line to indicate that there is a video
attached to the page. Although, something like this would:

<mypage.html>
   <ymedia:containsVideo>
      <puppies.swf> .

> From a site owner point of view this is significantly clearer than
> adding a typeof and thus is much more likely to gain adoption. 

I'd argue that it would hurt adoption of Yahoo's vocabulary because it
isn't clear how one should use ymedia:medium. I thought this is what the
common usage scenario would be for ymedia:medium -

A small <span property="ymedia:medium">video</span> about puppies.

Is that incorrect?

> In summary, I consider this a design pattern, not a bug, even if it
> sacrifices a principle.

If it is a design pattern, I don't think it is a very good one because
it is vague and there are better design patterns out there that
accomplish what you want to accomplish, such as the one I described above.

-- manu

-- 
Manu Sporny
President/CEO - Digital Bazaar, Inc.
blog: Absorbing Costs Considered Harmful
http://blog.digitalbazaar.com/2009/02/27/absorbing-costs-harmful