[microformats-discuss] URIs please!

[Kevin Marks]

On Jul 14, 2005, at 5:42 PM, Peter Janes wrote:

> Ryan King wrote:
>> On Jul 14, 2005, at 8:14 AM, Bud Gibson wrote:
>>> 2.  The presence of an XMDP cannot practically be assumed to mean  
>>> that any occurrence of an attribute value defined in the XMDP is to  
>>> be interpreted according to the XMDP's definition.
>> Right, but we're not looking for individual attribute values, we're  
>> looking for attribute values in context.
>
> I don't think it's necessarily true that a microformat will define a 
> hierarchy of attribute values.  Take rel="nofollow"[1], which defines 
> a single value, as an example: there's no structure involved, it is 
> significant no matter where it appears in a document.  My proposed 
> robots-exclusion profile[2] is an even more general case than 
> rel="nofollow" since it defines attribute values (class names) that 
> can be used on any subset of elements in a document in any combination 
> or order.
>
> (Some may debate that robots-exclusion is a microformat, since even in 
> its name it's targeted at crawlers.  To those folks I'd note that 
> rel="nofollow", which was created entirely for use by spiders, is 
> perhaps the most widely-adopted microformat out there; it certainly 
> has the most significant industry backing.)

Right, Peter, but there is a difference between an elemental format , 
which defines a single value, and a compound format like hCard.

Validating the existence of an elemental format is easy, as it is a 
single value; validating a more complex structure requires parsing.

http://www.microformats.org/wiki/elemental-microformat

Also, note the composability of the elements; you can make sense of 
rel="tag" within another format, even if you don't necessarily parse 
that format fully.