- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Mon, 8 Nov 2004 14:08:03 -0000
- To: "Dave Beckett" <dave.beckett@bristol.ac.uk>, "RDF Data Access Working Group" <public-rdf-dawg@w3.org>
> ISSUE: grammar lex/yacc shift/reduce conflicts > I raised this in: > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004Jul/0016.html > based on an IRC chat. No reply so far. The first shift/reduce > conflict I think is serious. This link points doesn't point to a message by Dave Beckett. Nor is it about lex/yacc shift/reduce conflicts. Andy -------- Original Message -------- > From: Dave Beckett <> > Date: 8 November 2004 12:15 > > Pulling my thoughts together in one email, my overall general concern > is that the language is already too large and still growing. I > expected a strawman language based on BRQL to be removing things as > well as adding them. > > I've seen a tendency to when given two choices, pick both. Which has > been making the language larger and full of syntactic sugar or a > sugary mess if you like. This is a flaw of RDF/XML that I see > starting to be repeated here. > > There are lots of items in this email, several of which I've brought > up in different places and I include pointers. I'll put ISSUE: > before each one I find significant. I could pull them out into > separate subject threads - my preference for tracking, but spawning > 6-7 new threads. > > Dave > > ----- > > ISSUE: Variables with $ or variables with ? > After the telcon discussion and preferences (vote?), I'm still > waiting for the editors to announce what they are doing / have done. > > The 2004-10-26 telcon > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0194.html > had strawpoll approximately no preference: 4 $: 5+1ish ?: 1 > which I saw as favouring $ alone. > > > ISSUE: PrefixDecl allowed before or after Select > After my posting: > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0161.html > and proposal: > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0164.html > and the telcon discussion 2004-10-26: > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0194.html > still waiting for any (if any) grammar change to be announced. > > > ISSUE: Comments in SPARQL - /**/ // OR # OR both > My initial posting > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0199.html > waiting for the editors to announce if there are any document changes. > I don't actually see any decision in the last telcon minutes > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0210.html > > > ISSUE: Commas or no commas > I've already seen user confusion when they tried to use ','s inside > WHERE (s, p, o) and omitting them outside with SELECT ?x ?y. I've > mentioned this many times as likely to happen. It's hard to remember. > > > ISSUE: OPTIONAL or []s > I've asked several times to pick just one of these. The WG looked > favourably at F2F on a syntax containing the latter only. This > is related to the more general need for a grouping construct - not > needed at all if nested optionals are ditched. > > > ISSUE: Keywords to be allowed in upper and lowercase > > Breaking with the trend, I'd like an alternative. > I'd like 'select' to be allowed as well as 'SELECT' for all keywords > since stylistically uppercase "shouting" is getting tiresome and this > is already done in RDQL, BRQL, SQL* languages and grammaras. Note: > This is NOT about making them case independent, allowing 'sElECt'. > > > ISSUE: SPARQL EBNF / grammar detail suggestions > I gave some layout suggestions in > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004JulSep/0524.html > some of which were added. > > Since then I've been through all the grammar in detail and I've got > more detailed suggestions: > > * Add a grammar terms SelectClause, ConstructClause, DescribeClause > as part of ReportFormat. > > * To make things easier for me in lex/yacc I renamed things that were > 0 or 1 (not lists) to be ThingOpt - it'd be nice if that was used, > but just a suggestion. I renamed FromClauseOpt, WhereClauseOpt. > > * Non-terminals used only once. > I deleted FromSelector and others as they are used once only as an > alias for another non-terminal. My preference to just put the > non-terminal in FromClause. (The particular non-terminal may > change since it's related to the prefix issue - could be QuotedURI > or URI.) > > PatternElement1 and SingleTriplePatternOrGroup are also used once > only. > > * I'm still not clear what GraphPattern1, PatternElementForms... are > for. I re-arranged and merged many non-terminals [6]-[14] just for > my convenience. > > * [12] PatternElementForms - 'SOURCE *' - I asked this before: > > > http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0025.html > Please explain where this syntax comes from and what it means. > > * Use shorter EBNF: [15] TriplePatternList ::= TriplePattern > TriplePattern* can be written more concisely as TriplePattern+ > Similarly for other lists such as GraphPattern. > > * I added VarOrURIList, VarList and URIList terms to handle the > optional comma messes. > > * Several things inside the expression evaluation can be merged with > little loss - ConditionalOrExpression into Expression, > StringEqualityExpression into ValueLogical, StringComparitor into > StringEqualityExpression, RelationalComparitor into > EqualityExpression, NumericComparitor into RelationalExpression, > AdditiveOperation into AdditiveExpression, MultiplicativeOperation > into MultiplicativeExpression, PrimaryExpression into > UnaryExpressionNotPlusMinus, NumericLiteral/TextLiteral both into > Literal > > * Use more of XML's EBNF and fix things up to match > http://www.w3.org/TR/2004/REC-xml11-20040204/#sec-notation > Use the correct syntax for terminals; <NAME> is not allowed as > symbol name in XML's EBNF. > [51], [61] ["A"-"Z"] is not legal. > [54] ["x", "X"] is not legal. > [57] ~[">", " "] is not legal > [48] (<NCNAME>)? doesn't need the ()s, similar in [59]. > [51] <A2Z> is missing an open < or has an extra trailing > > > > ISSUE: grammar lex/yacc shift/reduce conflicts > I raised this in: > http://lists.w3.org/Archives/Public/www-archive/2004Jul/0016.html > based on an IRC chat. No reply so far. The first shift/reduce > conflict I think is serious.
Received on Monday, 8 November 2004 14:09:18 UTC