[uf-discuss] Custom Fields Microformat?

[Tantek Ç elik]

On 11/26/06 10:49 AM, "Aaron Gustafson" <aaron at easy-designs.net> wrote:

> Tantek Celik [tantek at cs.stanford.edu] wrote:
>> Aaron,
>> 
>> DL/DT/DD in XHTML can already be used to semantically
>> represent property value sets and XOXO uses them for this
>> purposes.  Hence XOXO already solves this problem by reusing
>> semantic XHTML.
>> 
>> Tantek
> 
> I understand that, so should a DT-based XOXO within any microformat (hCard,
> hCal, hProduct, etc.) automatically be considered properties for that
> card/caledar/product? How would it work with a list of properties and values
> or natural language properties and values? It seems like some part of the
> XOXO spec should specify how to handle that (I couldn't find any mention of
> it, perhaps you could point me to the right place...?) or the scope of XOXO
> should be expanded to allow for situations like these.

Quite the opposite actually.

The goals of any format are data fidelity and interoperability over time and
space, to which microformats adds a few more principles, like ease of use
for humans first rather than machines (though even that is derived from
observing that formats easier for humans lead to better data fidelity).

Arbitrary extension of the properties/values of any microformat just leads
to significantly worse interoperability as people mutate it in numerous
directions - e.g. babel.  The only partial exception to that we have found
that appears to work in the wild is "tagging" - where there is an upfront
expectation of a semi-chaotic (but also emergent semi-orderly) folksonomy.
Yet folksonomies themselves make poor data formats, for the same reason.

Thus arbitrary extensibility is actually a design-antipattern for those
goals, and to be explicitly avoided when designing formats.

Since XOXO itself only defines nested lists (and sets) of items with
arbitrary properties/values (with a certain fixed known set for compat with
existing uses), there is no expectation that user/author defined properties
themselves will interoperate.  In that extent XOXO is a more like a
meta-format like XML, RDF, or JSON that itself can be used to define
data-type specific formats, rather than like hCard and hCalendar that are
used to represent and interchange specific types of data.

Thanks,

Tantek