Re: SHACL Compact Syntax, was Re: Fwd: Transition Request: 3 FPWGNOTE documents

FWIW I have made a simple switch that will make accidental clashes 
between the two compact syntaxes very unlikely: Instead of ending lines 
with ';' we now use '.' (like SPARQL/Turtle).

I wouldn't mind holding off the release of SHACL Compact Syntax and vote 
again next week. I do believe however that we could just as well go 
ahead as planned. The document had been visible to the public for quite 
a while now, without such feedback. I had also sent direct emails to the 
people in the acknowledgements section, without getting any response, so 
I assumed it was OK. And any WG Note is just a starting point, with the 
explicit goal of serving as input to future standardization efforts.

On the general topic I can only reiterate that the Shapes WG had made 
several resolutions that a Compact Syntax is produced and that it should 
look like ShExC. The explicit assumption was that this would be a 
deliverable by the WG, I believe it was even assigned to someone from 
the ShEx "camp". We are merely executing on those resolutions although I 
would have preferred if someone else had worked on them.

Given the unfortunate politics around this WG, we cannot make everyone 
happy.

Holger


On 25/05/2017 4:17, Sandro Hawke wrote:
> Tom's email, to which Irene is replying, was send to a W3C Member 
> Confidential mailing list (chairs@w3.org). She accidentally included 
> it in her reply, perhaps not knowing the list's confidentiality (which 
> is not obvious).   Here's my to reply to that list, which bears on 
> this this group:
>
>> My sincere apologies, Tom.  You mentioned this concern to me earlier, 
>> and then I completely forgot about it in the flurry of documents.  
>> That was a serious error on my part.
>>
>> I agree, it's a very bad architectural practice to design languages 
>> such that a non-trivial document could be syntactically valid in 
>> multiple languages while having different semantics.   We pretty much 
>> only see this in a few notoriously bad situations, like "1/2/2017" 
>> being either 2017-01-02 or 2017-02-01, depending on the locale.
>>
>> I suggest the Data Shapes Working Group withdraw its decision to 
>> publish this (or the Director not approve it), and instead delegate 
>> to an expected new SHACL CG to figure out a way to make the syntax 
>> disjoint from ShExC in at least the cases where the semantics are 
>> distinct, [then] publish it as a CG Report, much like ShExC, instead 
>> of a WG Note (since the WG will presumably have expired by then).
>
> Does that sound like a reasonably path forward?
>
> I guess another option would be to make a trivial change to the syntax 
> (before next week) to make it disjoint, but I believe the community 
> would be far better served by having the syntax be the same in places 
> where the semantics are the same.  If that's possible, it seems 
> worthwhile to take the time in a CG to figure that out in concert with 
> ShEx folks.
>
> Thoughts?
>
>       -- Sandro
>
>
> On 05/24/2017 11:57 AM, Irene Polikoff wrote:
>> I really do not think ShEx has a “copywrite" on an idea of a compact 
>> syntax. Its syntax itself was itself influenced by many different 
>> syntaxes/previous works, I am sure.
>>
>> Further, the syntaxes are not identical. They are similar. For 
>> example, SHACL has target declarations and it is supported in the 
>> syntax. The way cardinalities are expressed is different.
>>
>> I guess one option would be to modify the syntax to be even less 
>> similar. But I can’t think what could be done to make it 
>> significantly more different - because the information it is trying 
>> to express is very similar and it is expressed in an obvious way as a 
>> “property”, then a list of constraints for the values such as the 
>> data type, cardinality, etc. There is nothing novel or special in 
>> this format.
>>
>> I suppose one could change delimiters. However, many delimiters are 
>> quite standard and making them into something else would be very 
>> peculiar e.g., the use of ‘|” for ‘or’; the use of “;”  as a 
>> separator. These are used by many-many languages. With this, I am not 
>> sure what changes would be sufficient to ensure that SHACL and ShEx 
>> compact syntax can’t be confused. Should SHACL WG members object to 
>> the ShEx CG use of the words ‘shape’, ‘node shape’, etc.? Because 
>> this will be confusing to potential users - when they hear or see 
>> shape, they wouldn’t know which one.
>>
>> Overall, this sounds like an attempt to prevent SHACL from having a 
>> compact syntax so that for those who want a compact syntax, ShEx will 
>> be an only option. This is not good for the community and, to me, 
>> sounds like a desire to block progress and deprive users of SHACL of 
>> features. No one should have a right to do this, especially not on 
>> the open web.
>>
>>
>>> Begin forwarded message:
>>>
>>> *From: *Tom Baker <tom@tombaker.org <mailto:tom@tombaker.org>>
>>> *Subject: **Re: Transition Request: 3 FPWGNOTE documents*
>>> *Date: *May 24, 2017 at 11:05:47 AM EDT
> ...