Comments to May 2 working draft

While I was working on updating the grammar files for our XPath/XQuery 
parser, I noticed some problems with the new working draft:

[XPath & XQuery]
1) the DEFAULT state is missing the handler for QName (that should trigger 
a transition to OPERATOR)

2) the QNAME state is no more needed (the only keyword that triggers this 
state is OfType, that is no more in the specs)

3) the transition rules don't allow the syntax 
"document-node(element(xxx))", because the "element(" string is not 
recognized in the KINDTEST state that "document-node(" triggers (in that 
state, "element" is recognized as a QName, then a transition is made to 
CLOSEKINDTEST, where the "(" is not allowed).
So, "document-node(" should probably trigger the DEFAULT state (not the 
ITEMTYPE, to not allow an occurrence indicator after the "element(" keyword)

4) this is probably just a side effect, that would need an example to make 
it "official": the query "/ instance of document-node()" is not a valid 
one, because "/" in the DEFAULT state doesn't trigger a transition to the 
OPERATOR state, and "instance of" is only recognized in that state. So the 
"instance" word is recognized as a QName, and "of" is considered an error. 
The possible solutions I see are:
   a) specify that the user needs to write "(/) instance of document-node()"
   b) allow "instance of" in the DEFAULT state
   c) add a parsing note specifying that "/" should trigger the OPERATOR 
state if followed by a space

[XPath only]
1) the lexical rules in the appendix A.2.2 contains some "strange" 
keywords, that looks like remains of the previous grammar rules, or 
references to XQuery keywords that the publishing process still generated.
They are:
- in the DEFAULT state, "OfType","RBrace" and "LbraceExprEnclosure"
- in the OPERATOR state, "Global", "LbraceExprEnclosure", "InContext", 
"OfType", "RBrace"
- in the KINDTEST state, "LbraceExprEnclosure", "InContextForKindTest", and 
"Global"
- in the CLOSEKINDTEST state, "LbraceExprEnclosure"
- in the SCHEMACONTEXTSTEP state, "LbraceExprEnclosure"
Also, there is a QMark symbol that should be displayed as "?"

[XQuery only]
1) the lexical rules in the appendix A.2.2 contains some "strange" 
keywords, that looks like remains of the previous grammar rules, or 
references to XQuery keywords that the publishing process still generated.
They are:
- in the DEFAULT state, "OfType"
- in the OPERATOR state, "InContext", "OfType"
Also, there is a QMark symbol that should be displayed as "?"

Alberto

-------------------------------
Alberto Massari
Progress Software
http://www.StylusStudio.com

Received on Monday, 5 May 2003 10:00:13 UTC