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Re: literal value terminology (was: Re: Review of MT)

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Sat, 19 Jan 2002 10:07:53 +0200
To: ext Sergey Melnik <melnik@db.stanford.edu>, Pat Hayes <phayes@ai.uwf.edu>
CC: RDF Core <w3c-rdfcore-wg@w3.org>
Message-ID: <B86EF5F9.BDFF%patrick.stickler@nokia.com>
On 2002-01-19 3:04, "ext Sergey Melnik" <melnik@db.stanford.edu> wrote:

> Pat Hayes wrote:
>> 
>>> 
>>>>>    Or by "literal value" do you mean the member of the value space
>>>>>    of some datatype?
>>>> 
>>>>  Yes, that is what I meant.
>>> 
>>> Good. I had hoped that was the case. What threw me
>>> was the adjective 'literal' in front of value. It
>>> seems to suggest that the values are the strings
>>> (literals) rather than the members of the value
>>> space of the datatype.
>>> 
>>> Perhaps you could just say 'value'? and leave the
>>> 'literal' off?
>>> 
>>>>>    If the latter, then don't we need some treatment of lexical datatypes,
>>>>>    value spaces, lexical spaces, and (presumably also) canonically
>>>>>    lexical spaces in the core MT?
>>>> 
>>>>  Well, we need it eventually.  But in the meantime, the MT can just
>>>>  say that literals denote literal values (whatever those turn out to
>>>>  be).
>>> 
>>> Fair enough. Though I think it would be clearer, in
>>> light of the vocabulary of the "foundation" datatyping
>>> document (sections 1-3 of Sergey's document) to just
>>> say 'value' rather than 'literal value'.
>> 
>> Hmm. The trouble is that plain "value" could mean anything at all.  I
>> want to allow the MT to conceptually distinguish values of literals
>> from semantic values in general, ie resources. (They might turn out
>> to be the same; but they might not also and I'd like to stay
>> agnostic.)
>> 
>> How about calling them "datatype values" ? That avoids the use of
>> "literal" as an adjective and also makes an obvious connection with
>> datatyping. It also follows the DAML usage, which distinguishes
>> 'object' classes from 'datatype' classes, which are classes of
>> datatype values.
>> 
>> Anyone got strong views on this? Speak now! Unless there are strong
>> objections I will make this change.
>> 
>> Pat
> 
> Speaking now :)
> 
> I don't like the name "datatype values" particularly... I already made a
> suggestion long ago, but let me repeat it here again anyway. For
> orthogonality, I'd rename "literals" to "literal tokens/symbols/etc.",
> and make "literal values" just "literals". So you get
> 
> I(resource URI) = resource
> I(literal token) = literal
> 
> It just looks more consistent than
> 
> I(resource URI) = resource
> I(literal) = literal value
> 
> Of course, such change would involve a lot of find-&-replacing both in
> the draft and in our minds, but it does help to avoid confusions
> (Patrick's email is another example). If we leave it like it is now, I'm
> afraid we (well, you Pat) would have to clarify it over and over
> again...
> 
> Sergey

But I think that 'literal' is the problem. We're not
talking about a lexical form, and 'literal' is too
widely understood to correspond to the string representation
of the value. Likewise, a literal can be something
other than a datatype value -- such as an XML fragment,
etc. -- so the term 'datatype value' seems to be the
most precise in communicating "a member of the value
space of a datatype" and not any string representation
(literal, lexical form, etc.).

Patrick


--
               
Patrick Stickler              Phone: +358 50 483 9453
Senior Research Scientist     Fax:   +358 7180 35409
Nokia Research Center         Email: patrick.stickler@nokia.com
Received on Saturday, 19 January 2002 05:17:32 EST

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