Comments on PR-rdfa-syntax-20080904

While I work for a member company (Talis), the opinions below are my own,
though I suspect the summary at least will coincide with that of the company
rep (cc'd).

Hope you can make sense of my plain-text markup, sections: Summary, General
Points, Substantive Points, Editorial, Nitpicking

*** Summary ***

While I believe the document likely contains all the information necessary
to use RDFa I can't tell for sure. The way it's currently organized leads me
to suggest it needs one or two more revisions before proceeding any further.
IMHO it could use compressing, making more formal, and significant chunks
moving to other docs - some of the informative bits to the primer, the CURIE
def to another spec. Pragmatically, as it stands I suspect most
publishers/consumers & parser authors will simply get confused.

*** General Points ***

a large proportion of this doc is informative (and a lot of small sections
gives the impression of it being piecemeal, rather than a coherent spec)

I think it would allow more flexibility in future spec creation if CURIES
were defined in an independent spec

while Relax NG might not be as widely adopted as DTDs, for the purposes of a
specification like this, such a description would be a lot more helpful than
the DTDs

the distinction rendered data vs. structured data doesn't seem clear

how does a parser distinguish between intentional RDFa and HTML tag soup?

*** Substantive Points ***

* How to Read this Document *
"...authors don't need to understand RDF to use it"

While I appreciate the intent, I believe this statement to be wrong -
accurate communication (of data) requires both the producer and consumer to
understand the language. Suggest rewording to something along the lines of:
"...authors don't need complete understanding of RDF to use it"

* 3.1. Statements *

"A statement is a basic unit of information that has been constructed in a
specific format to make it easier to process"

ew.

* 3.7. Graphs

appears unfinished...

* 4.1. Document Conformance *

This seems a bit messy both substantively & editorially. For starters, where
is @version in the http://www.w3.org/1999/xhtml namespace?

* 4.3. RDFa Processor Conformance *

"A conforming RDFa Processor MAY make available additional triples that have
been generated using rules not described here, but these triples MUST NOT be
made available in the [default graph]. (Whether these additional triples are
made available in one or more additional [RDF graph]s is
implementation-specific, and therefore not defined here.)"

This seems over-constrained. If I have a doc which contains RDFa plus GRDDL
plus [something not yet defined] RDF-in-HTML data, I would expect them to at
least be able to be interpreted as a single graph. i.e. the graph scope
should be the document, not the RDFa processor's interpretation. (That's
assuming "default graph" is meant to mean what I think - it's not defined
here as far as I can see). I don't see how Appendix C. Deployment Advice
fits in here either.

* 5.2. Evaluation Context *
This section seems loosely defined for normative material. I don't think
it'd take much effort to tie it to the XML DOM, in a similar fashion to 5.5.
Sequence (SAX).

Use of [] on the CURIE attributes seems inconsistent.

// here I got lost

* 9.3. @rel/@rev attribute values *

unnecessary repetion of HTML defs - a single example would do (i.e.
rel="cite")


*** Editorial ***

various places:
mark-up => markup

* 2.1. The RDFa Attributes *

the "X in RDF terminology" bits should perhaps be linked to corresponding
places in the RDF Primer

* 3. RDF Terminology *

Sytax => Syntax

There are a few unfulfilled refs like <em>[triples]</em>

In the informative sections, it may be more reader-friendly to use
'property' rather than 'predicate'.

consider merging 3.1 Statements with 3.2 Triples


*** Nitpicking ***

* Abstract *

"The modern Web is made up of an enormous number of documents that have been
created using HTML."
=>
"The current Web is primarily made up of an enormous number of documents
that have been created using HTML."

----

"RDFa is a specification for attributes to express structured data in any
markup language."
Is RDFa specified for any language other than XHTML? Where?

----

"rendered data can be copied and pasted along with its relevant structure"
Yuck, something more like this seems more appropriate:
"rendered data can be manipulated and reused along with its relevant
structure"

----

* Motivation *
"RDF/XML [RDF-SYNTAX] provides sufficient flexibility to represent all of
the abstract concepts in RDF [RDF-CONCEPTS]."
- with certain limitations, e.g. properties which can't be expressed as
qnames can't be serialized as RDF/XML, e.g. http://example.com/1234

----

'hard-wired' - not sure everyone will understand, anyone got a synonym?