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Re: XMLification of presentation syntax

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Sat, 03 May 2008 21:22:50 +0100
Message-ID: <481CC99A.3010706@hplb.hpl.hp.com>
To: "Boley, Harold" <Harold.Boley@nrc-cnrc.gc.ca>
Cc: "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>

Boley, Harold wrote:
> Also referring to
> http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0026.html
> 
> recall the Resolution's second sentence:
> "Of course, XML entities can be used."
> 
> Nothing better than XML entities has come up since then.
> 
> So I see a consensus to soon replace the informal "expands into"
> of Example 4 etc. with the emerging Consts/CURIEs in PS
> (http://lists.w3.org/Archives/Public/public-rif-wg/2008May/0015.html ff)
> and with entities in XML (as discussed in this thread).

Not wishing to cause any confusion but surely the point is that these 
strings are just IRIs. If some serializer chooses to use Entities or not 
to break up the IRIs then that is up to them. We might choose to use 
them in the examples for readability, but there should be no 
*requirement* to use them. From the point of view of any RIF reading 
software the Entity expansion is handled by the XML parser and they just 
see the IRI and should not care about any possible entity encoding 
behind the scenes.

Dave
-- 
Hewlett-Packard Limited
Registered Office: Cain Road, Bracknell, Berks RG12 1HN
Registered No: 690597 England


> 
> -- Harold
> 
> 
> -----Original Message-----
> From: Hassan At-Kaci [mailto:hak@ilog.com] 
> Sent: May 3, 2008 8:09 AM
> To: Michael Kifer
> Cc: Boley, Harold; Public-Rif-Wg (E-mail)
> Subject: Re: XMLification of presentation syntax
> 
> Michael Kifer wrote:
>> XML does not understand curie macros, so rif:iri is just that for XML.
>> In the presentation syntax, rif:iri is not a "rif:iri" but a macro that
>> expands into something long. So, the earlier use of rif:iri and similar in
>> XML was actually a mistake.
> 
> OK. So you mean to say, "... HAS BEEN actually a mistake" (and still
> IS as far I understand). Correcting this simple mistake is easy then.
> How come it has not been fixed in all the BLD documents and examples
> after the resolution was passed 6 months ago? How many other such
> "mistakes" remain in the current BLD draft that should be so corrected?
> My question is a very pragmatic one: I am trying to implement the dang
> thing.
> 
>> XML uses entities as a similar macro device. A number of standards 
>> (incl OWL) use curies in their abstract syntax examples and entities in XML
>> examples.
> 
> Again - whatever. I was not asking for an XML tutorial. I was just
> trying to find out what to code reading the official output of this WG.
> Doing so, I am putting myself in the shoes of the average Joe reading
> the latest BLD document trying to make practical sense out of our
> official specs. My point is that if the BLD specs still contain such
> inaccuracies despite they having been officially resolved, it makes
> implementing them a bit problematic and frustrating. Or perhaps it is
> too much to ask from this busy group? ;-)
> 
>> 	--michael  
>>
>>
>>> Boley, Harold wrote:
>>>> There is the Resolution from F2F7 I referred to below, Harold
>>> Whatever... And so how come all the BLD documents since then (which
>>> was back in 2007) use rif:iri and not &rif;iri ? Again - what are
>>> the pros and cons for one of the other? I do not recall anything
>>> about that resolution, nor why it was so important, nor why examples
>>> since then have not adhered to it. Please comment and/or explain.
>>>
>>> -hak
>>>
>>> PS/ I understand everything in the RIF XML notation is a (still) a
>>>      moving target, but at least we should make our examples as
>>>      consistent as possible with what has been decided thus far.
>>>      How can anyone prototype this thingie otherwise?
>>>
>>>> PS: OWL 2 also uses entities for such purposes
>>>> (switch to XML: http://www.w3.org/TR/2008/WD-owl2-primer-20080411/#Basic_Notions):
>>>> http://www.w3.org/TR/2008/WD-owl2-primer-20080411/#Appendix:_The_Complete_Example
>>>>
>>>>
>>>> -----Original Message-----
>>>> From: Hassan At-Kaci [mailto:hak@ilog.com] 
>>>> Sent: May 2, 2008 10:28 PM
>>>> To: Boley, Harold
>>>> Cc: Public-Rif-Wg (E-mail)
>>>> Subject: Re: XMLification of presentation syntax
>>>>
>>>> Boley, Harold wrote:
>>>>> Given an entity declaration
>>>>> (http://www.w3.org/TR/2006/REC-xml11-20060816/#sec-entity-decl),
>>>>>
>>>>> say
>>>>>
>>>>> <!ENTITY rif "http://www.w3.org/2007/rif#">
>>>>>
>>>>> we can use an entity reference
>>>>> (http://www.w3.org/TR/2006/REC-xml11-20060816/#sec-references),
>>>>>
>>>>> say
>>>>>
>>>>> &rif;
>>>>>
>>>>> so that, e.g.,
>>>>>
>>>>> <Const type="&rif;iri">
>>>>>
>>>>> stands for
>>>>>
>>>>> <Const type="http://www.w3.org/2007/rif#iri">.
>>>>>  
>>>>> -- Harold
>>>> Hmmm... This is then different than what is in the latest BLD draft...
>>>> Note that his makes XML serialization look quite different than what can
>>>> be seen therein. Has this been discussed anywhere? If so when? (I  would
>>>> then have missed it!) The last I recall (and in the latest BLD draft) we
>>>> still had things like "rif:iri" not "&rif;iri". Not that I mind one way
>>>> or the other (besides matters of taste/style), but could you please fill
>>>> me in on why one rather than the other? (In the current implementation I
>>>> am playing with I serialize such a  Const as follows:
>>>>
>>>>        <Const typespace="rif" typename="iri">
>>>>
>>>> which I find clearer and less arcane. But this is my taste. I can surely
>>>> make it produce your entity-style notation if this is what this group
>>>> prefers.)
>>>>
>>>> -hak
>>>>
>>>>> -----Original Message-----
>>>>> From: Hassan At-Kaci [mailto:hak@ilog.com] 
>>>>> Sent: May 2, 2008 8:47 PM
>>>>> To: Boley, Harold
>>>>> Cc: Public-Rif-Wg (E-mail)
>>>>> Subject: Re: XMLification of presentation syntax
>>>>>
>>>>> Boley, Harold wrote:
>>>>>> Hi Hassan,
>>>>>>
>>>>>> Good to learn about your progress here, which should help soon in
>>>>>> the development of test cases etc.
>>>>>>
>>>>>> There is this Resolution from F2F7:
>>>>>> "RESOLVED: In the XML syntax, we'll use full IRIs (not qnames or
>>>>>> curies) for Const types, etc. Of course, XML entities can be used."
>>>>>> http://www.w3.org/2005/rules/wiki/Resolutions
>>>>>>
>>>>>> I plan to update the XML syntax using entities, as in this example:
>>>>>>
>>>>>> "cpt:purchase"^^rif:iri ==> <Const type="&rif;iri">&cpt;purchase</Const>
>>>>> Huh? Could you pls kindly comment on the &rif; and  &cpt; thingies?
>>>>>
>>>>>> cpt:purchase and rif:iri are tokenized as pairs of atomic strings
>>>>>> (e.g., the pairs colon('cpt','purchase') and colon('rif','iri'),
>>>>>> respectively), from which the XML is ultimately generated.
>>>>>>
>>>>>> Generally, for a single colon on both sides of the doublehat:
>>>>>>
>>>>>> "w:x"^^y:z  =tokenize=>  doublehat(colon('w','x'),colon('y','z'))
>>>>>>               . . .
>>>>>>             =xmlgen=>    <Const type="&y;z">&w;x</Const>
>>>>> Same question re: &y; and  &w; ...
>>>>>
>>>>> Thanks.
>>>>>
>>>>> -hak
>>>>>
>>>>>> We could forbid multiple colons on either side of the doublehat
>>>>>> or adopt an appropriate escaping convention for colons, hats, etc.
>>>>>> In case there is no colon on either side of the doublehat,
>>>>>> tokenizing of that side returns a single atomic string.
>>>>>>
>>>>>> Best,
>>>>>> Harold
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Hassan At-Kaci [mailto:hak@ilog.com] 
>>>>>> Sent: May 2, 2008 1:39 PM
>>>>>> To: Boley, Harold
>>>>>> Cc: Public-Rif-Wg (E-mail)
>>>>>> Subject: XMLification of presentation syntax
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> While this ping-pong exchange has been raging on the topic of the -
>>>>>> by now - (in)famous, notation "foo:bar"^^rif:buzz, I have been myself
>>>>>> laboring on more pedestrian pursuits generating a compiler for the
>>>>>> presentation syntax that would at least be able to parse the syntax
>>>>>> of the examples given in [1] and produce the XML trees rendered as
>>>>>> written by you in that document.
>>>>>>
>>>>>> Here is what I am not sure to understand right. Your explanation
>>>>>> will be most appreciated - so I can proceed and finish that thing
>>>>>> already!... :-) (I am very close actually - but I'd be unwise to
>>>>>> crow victory too soon as there may be further such snags lurking
>>>>>> still.)
>>>>>>
>>>>>> The EBNF rules you give for this pertain to the non-terminal Const
>>>>>> for which you give the following rules (in [2]):
>>>>>>
>>>>>>    Const          ::= '"' UNICODESTRING '"^^' SYMSPACE
>>>>>>    SYMSPACE       ::= UNICODESTRING
>>>>>>
>>>>>> Then, you give the following (informal context-sensitive) translation
>>>>>> (meta-)rule for expressing this construct in XML (see [3]):
>>>>>>
>>>>>>    unicodestring^^space ==> <Const type="space">unicodestring</Const>
>>>>>>
>>>>>> Note that this EBNF uses two tokens '"' and '"^^' and NOT three tokens
>>>>>> '"', '"', and '^^', so that this begs the question of how what goes in
>>>>>> between '"' and '"^^' gets interpreted (especially ':').
>>>>>>
>>>>>> You give examples of how this is actually used to produce the XML
>>>>>> encoding of the presentation syntax, such as in Example 4 of [4] :
>>>>>>
>>>>>>    "cpt:purchase"^^rif:iri ==> <Const type="rif:iri">cpt:purchase</Const>
>>>>>>
>>>>>> Now, I note the following points in this example:
>>>>>>
>>>>>> a. cpt:purchase (without quotes) is the UNICODESTRING. By that, I
>>>>>>     understand that it is tokenized as a single atomic string (namely,
>>>>>>     the string 'cpt:purchase' where ':' is part of the string).
>>>>>>
>>>>>> b. rif:iri (also without quotes) is also a UNICODESTRING, and thus
>>>>>>     it too is tokenized as a single atomic string.
>>>>>>
>>>>>> The above makes me think that the UNICODESTRING could be anything
>>>>>> not containing special chars (including ':' and such that may have
>>>>>> other special meaning in XML). Am I right ?
>>>>>>
>>>>>> My question: "Is ':' given any special meaning? In other words, is
>>>>>> 'cpt:purchase' an XML local name, or is it that 'cpt' is the XML
>>>>>> namespace and 'purchase' the XML local name ?
>>>>>>
>>>>>> Thanks for clarifying...
>>>>>>
>>>>>> -hak
>>>>>>
>>>>>> References:
>>>>>>
>>>>>> [1]http://www.w3.org/2005/rules/wiki/BLD
>>>>>> [2]http://www.w3.org/2005/rules/wiki/BLD#EBNF_for_the_RIF-BLD_Rule_Language
>>>>>> [3]http://www.w3.org/2005/rules/wiki/BLD#Translation_of_the_RIF-BLD_Condition_Language
>>>>>> [4]http://www.w3.org/2005/rules/wiki/BLD#XML_for_the_RIF-BLD_Condition_Language
>>> -- 
>>> Hassan At-Kaci  *  ILOG, Inc. - Product Division R&D
>>> http://koala.ilog.fr/wiki/bin/view/Main/HassanAitKaci
>>>
>>>
>>>
>>>
>>
>>
>>
> 
> 
Received on Saturday, 3 May 2008 20:23:17 GMT

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