[whatwg] Predefined classes are gone
ian at hixie.ch
Wed Aug 8 16:30:45 PDT 2007
I'm not exactly sure what the context of this e-mail was (it seemed to be
a non-sequitur relative to its parent e-mail in the thread). It seems,
however, that it was attempting to suggest a solution without describing
the problem being solved, which makes it difficult to evaluate. I've
mostly addressed the syntactical and factual statements in the e-mail
below, but since it wasn't clear what problem was being addressed, no
changes have been made to the spec.
On Wed, 8 Aug 2007, cr wrote:
> > >
> > > the start. I think the initial idea was that the class attribute
> > > would cover the the semantics while CSS the presentation of those
> > > semantics. The only problem is that earlier specs left those
> > > semantics undefined, with no way to define them unambiguously
> you can unambiguously define the semantics of an element w/ RDFa..
You can unambiguously define the semantics of an element with many
features, such as RDFa, class attributes, structured prose, etc. All it
takes is a well-defined specification describing the conventions of the
way the semantics are conveyed.
> one might think of an element class='author' being short for
> 'formattedAuthorValue'. where does 'formatted value' of this come in?
> the stylesheet. but this is all vague and based on assumptions. if your
> use case is common enough a standard way to describe it has been layed
> out on a microformat wiki somewhere..
I don't really follow.
> discovering/parsing RDFa is simpler than microformats as it doesn't need
> to be special-cased for each scenario,
I don't really see why you think RDFa needs any less special-casing than
your typical Microformat.
> and unlike microformats is infinitely flexible in what it can represent
Some might argue that the inflexibility of Microformats is part of its
> - doing so without requiring predefined classes or risking name conflict
> with existing 'non-semantic' classnames.
In practice, though, this hasn't really been a problem.
> attribute :property describes the property, so theres no confusion as to
> whether the class was just thrown in for styling purposes or was
> supposed to mean something specific. the properties themselves are
> resolvable to URIs. eg, dc:modified becomes
> http://purl.org/dc/terms/modified, the agent can look up a document at
> this URL, discover the class is a subclass of 'dc:date', then
> automatically display the modified times on a calendar or timeline.
> likewise, you could define a 'horror:killed' attribute, benefit from the
> existing agents without requiring approval from the microformat gods..
Requiring "approval" (or rather, requiring a broad consensus) is always
going to be important for the conveying of semantics to a wide audience,
regardless of the syntax. Equivalently, when your audience is small, you
don't need anyone's approval to do anything to convey semantics, again
regardless of what your syntax is.
> so, everything you describe is solvable, and has already been thought
> about and solved in at least one way..
Indeed, many ways.
> also, microformats ses the automatically-tooltipped/human-readable
> 'title' attribute for the machine-readable encoded format (and the
> contents of this field are definitely not the 'title' but some sort of
> attribute value), which is bizarre on several levels... RDFa uses the
> 'content' attribute for this, preferring that over the innerHTML for the
> machine-readable format when it is available. im not sure whats worse -
> the nameclashing with existing web content, the unextensibility, or the
> reuse of existing attributein unidiomatic ways..
I recommend bringing up such issues with the Microformats community.
> RDFa is potentially a solution to your problems.
We're still trying to work out what the problems are, so it's not clear
that one can establish what the solutions can be yet.
Ian Hickson U+1047E )\._.,--....,'``. fL
http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,.
Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
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