[uf-dev] value-class-pattern call for implementations

[Ben Ward]

Hi there all parser-author-types,

This is a heads up concerning the value-class-pattern (né, value- 
excerption-pattern) work that's been going on for the past… well, it's  
been a while. And now it's nearly done.

   • http://microformats.org/wiki/value-class-pattern

The work has come out of value-excerption-brainstorming, been well  
tested against browser behaviours for accessibility feedback, and  
Tantek and I have got a document together specifying the behaviour of  
value-excerption in this general usage.

In short:

   • Value-excerption (the "value" classname in hCard) got implemented  
globally in some parsers, but was never specced that way
   • It proved useful in some scenarios, and offers publishers some  
additional flexibility in their mark-up, so rather than declare the  
global implementation a bug, we've specc'd it.
   • In addition, value-excerption also proved to be the strongest  
line of development in our ongoing quest to provide an alternate  
pattern for datetime and enumeration publishing scenarios where the  
required content was undesired in visible pages, and the abbr-pattern  
could be semantically unsuitable. An extension of value-excerption has  
been added to parse values from @title attributes. And non-visible  
scenarios accounted for (see the wiki page for all of that in full).

We think it's solid, every informal conversation we've had with parser  
authors so far has OK'd it. There may be places that need tightening  
up, so please say if you find a problem, but the core of it is ‘done’  
and given the accessibility and internationalisation implications, we  
are very keen that this pattern be pushed in place of examples where  
problems are known.

We're asking that you please attempt to work with this pattern,  
feedback on any problems, but aim to implement this in future releases  
of your parses, knowing that that future microformat examples will be  
instructing authors to use this pattern, and existing ones will be  
revised soon.

By all means add things to the -issues page as needed.

There are, of course a massive number of people who share the credit  
for this work, brainstorming having taken place around these issues  
and the establishment of this solution itself. So, thank you.

Cheers,

Ben