Re: Summary: Annotation Syntax Proposals

On 19/01/2021 20:56, thomas lörtsch wrote:
> Thanks, Andy!
> 
> I wonder if the following are possible:

Lots of things are possible because these are tokens (done before 
grammar rules applied) and so have precedence over the grammar rules. So 
while it produces a grammar without ambiguity it needs further testing 
to make sure that the meaning of some forms has not changed or some 
forms aren;'t what people expect.

(Assuming we stick to the simple level of parsing technology needed for 
Turtle and SPARQL and the rest.)

> A)   :s :p :o  *{ :y :z } .
> B)   :s :p :o  *{ :y :z }* .
> C)   :s :p :o  {* :y :z *} .

Even though * has meaning in SPARQL for property paths, it (probably) 
works because it is positional.

This is a consequence in SPARQL:

:subject :predicate :object *{ :derivedFrom* ?URL } .

((
FWIW: For B and C the * may cause email clients to bold plain text and 
markdown to italicise.  !!!!!
))

Observation:
* can be the end of a prefix name with \ so can end the object.

This is not blocker.

[172s]  PN_LOCAL_ESC  ::=
   '\' ('_' | '~' | '.' | '-' | '!' |
         '$' | '&' | "'" | '(' | ')' | '*' |
         '+' | ',' | ';' | '=' | '/' | '?' | '#' | '@' | '%')

> Richard passingly proposed A a few weeks ago, together with the IMO rather convincing argument that it’s called RDF* after all.

Note: There has been suggestions to call the CG work "RDF-star" to make 
it searchable as a name.

> Personally I like A.
> 
> Given the very peculiar semantics of RDF* I’d strongly prefer if it didn’t use "@" but left that character for a semantics that treated attributed triples as belonging to the interpretation, not the syntax.

@ is language tag and "legacy" directive. We've mostly run out of unused 
ASCII squiggles which is why we have two character tokens now.

`` might be more appropriate for interpretation anyway.

What will be open are keywords.

[OT: EricP will suggest other Unicode codepoints not on the keyboard 
¯\_(ツ)_/¯ ]

     Andy

> 
> I tend to have difficulties reading {| … |} when the font size is small and generally I’m glad about every character I don’t have to type (or read).
> 
> Thomas

Received on Wednesday, 20 January 2021 11:15:35 UTC