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Re: agenda 12 Feb telecon

From: Sandro Hawke <sandro@w3.org>
Date: Wed, 12 Feb 2014 07:01:36 -0500
To: Eric Prud'hommeaux <eric@w3.org>,Guus Schreiber <guus.schreiber@vu.nl>
CC: RDF WG <public-rdf-wg@w3.org>
Message-ID: <00256728-d45d-4cdb-b330-5e08cc6c4628@email.android.com>
On February 12, 2014 6:10:20 AM EST, Eric Prud'hommeaux <eric@w3.org> wrote:
>* Guus Schreiber <guus.schreiber@vu.nl> [2014-02-11 20:07+0100]
>> We will have our penultimate telecon tomorrow. Agenda is at:
>> 
>>     https://www.w3.org/2011/rdf-wg/wiki/Meetings:Telecon2014.02.12
>> 
>> Editors: pls check the draft static REC versions [1].
>
>Inspecting Turtle's BNF, I noticed that while addressing DBooth's req
>for comments describing the numeric characters, I moved an "EXPONENT)"
>from DOUBLE to STRING_LITERAL_SINGLE_QUOTE:
>[[
>[21] 	DOUBLE 	::= 	[+-]? ([0-9]+ '.' [0-9]* EXPONENT | '.' [0-9]+
>EXPONENT | [0-9]+
>[23] 	STRING_LITERAL_SINGLE_QUOTE 	::= 	"'" ([^#x27#x5C#xA#xD] | ECHAR
>| UCHAR)* "'" EXPONENT) /* #x27=' #x5C=\ #xA=new line #xD=carriage
>return */
>]] —
><https://dvcs.w3.org/hg/rdf/raw-file/c3830fb585f1/rdf-turtle/turtle-bnf.html#grammar-production-DOUBLE>
>
>I think this is pretty non-controversial so I've fixed this in editors'
>draft and REC in <https://dvcs.w3.org/hg/rdf/rev/53130fe8be3b>.
>
>More interestingly, I noticed that we deviated from SPARQL's definition
>of strings 20 months ago when a re-gen of the HTML grammar stripped
>some ()s, going from:
>
>[157s] STRING_LITERAL_LONG1 ::= "'''" (("'" | "''")? ([^'\] | ECHAR |
>UCHAR))* "'''"
>[158s] STRING_LITERAL_LONG2 ::= '"""' (('"' | '""')? ([^"\] | ECHAR |
>UCHAR))* '"""'
>to:
>[25]   STRING_LITERAL_LONG1 ::= "'''" (("'" | "''")?  [^'\] | ECHAR |
>UCHAR) * "'''"
>[26]   STRING_LITERAL_LONG2 ::= '"""' (('"' | '""')?  [^"\] | ECHAR |
>UCHAR) * '"""'
>—
><https://dvcs.w3.org/hg/rdf/raw-file/b40e79fe8bbc/rdf-turtle/turtle-bnf.html>
>
>In the former language, <s> <p> """ "\u0061 """ . is legal and in the
>latter, an embedded quote must not be followed by ECHAR (e.g. \") or
>UCHAR (e.g. \u0061). Unfortunately, this change was pre-Trig so the
>issue exists there as well.
>
>I looked for tests with long (triple-quoted) strings with one or two
>quotes followed by a backslash. We have none, but SPARQL does:
>data-r2/syntax-sparql1/syntax-lit-17.rq:3:SELECT * WHERE { :x :p
>'''Long''\\Literal with '\\ single quotes ''' }
>data-r2/syntax-sparql1/syntax-lit-20.rq:3:SELECT * WHERE { :x :p
>"""Long""\\Literal with "\\ single quotes""" }
>
>The closest we have is
>LITERAL_LONG2_with_1_squote.ttl: <http://a.example/s>
><http://a.example/p> """x""y""" .
>but the nested ""s can be parsed by taking the longer of alternatives
>of ('"' | '""').
>
>What to do:
>
>I propose the bold step of restoring the SPARQL grammar, noting that it
>doesn't change any of our test results.
>

Argh.   Either that or we put it in the errata now.

So this raises the ongoing-test-suite question.  We should add this (non-normatively, like the errata) to the test suite as well...  what exactly will be the process for that, post-REC?

    - Sandro

>
>> Guus
>> 
>> [1] https://www.w3.org/2011/rdf-wg/wiki/Main_Page#REC_drafts
>> 
Received on Wednesday, 12 February 2014 12:06:58 UTC

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