Re: read BLD draft for f2f

Michael Kifer wrote:

>> 2. The scope of rif:local is not defined. The current phrasing "local to 
>> the various sets of RIF formulas" is not sufficiently precise, 
>> especially in the light of our requirement to support ruleset merging. 
>> I've previously suggested dropping rif:local and just having rif:iri. 
>> Presumably in some future phase we will add modules, as previously 
>> discussed, and at that point we will be able to be precise about the 
>> scoping of rif:local.
> 
> Yes. I now added a "TODO" in the appropriate place. We have to decide what
> a ruleset actually is. For instance, will we have an #include statement?
> Import statement?

Quite.

>> 5. In section 2.2.1.1 it states "This means that no variables or complex 
>> terms are allowed as slot names in the basic logic dialect." Yet the 
>> example in section 2.2.1.3 uses variables for slot names. If the 
>> restriction is indeed required then frames are not usable for RDF 
>> representation and the RIF/RDF representation will be to be reworked.
> 
> I fixed that. This statement actually refers to slotted terms, not frames.
> The reason for disallowing variables over slots in uniterms is the lower
> complexity of the unification. There is no reason for this restriction from
> the semantic point of view.

Phew, that makes sense.

>> 6. rif:text is not included in the list of primitive data types but is 
>> used (and needed) in the RDF compatibility section. The XML syntax for 
>> it will need to be defined.
> 
> Need to decide how to exactly incorporate @lang and such.

>> 8. In section 4.2.1 the mapping of plain literals with a language tag 
>> talks about replacing occurrences of "@" with "@@". I would prefer that 
>> we have a separate representation of text in the concrete syntax and 
>> avoid such mangling or simply avoid the concrete syntax altogether. If 
>> we stick to the current concrete syntax then (editorial) it should be 
>> made clearer that that transformation is an artifact of the concrete 
>> syntax and not relevant to the XML encoding or to any actual RIF processor.
> 
> I do not see how we can get rid of the presentation syntax. This means that
> we either give no examples or we use abstract or XML syntax. The latter two
> options mean that mere mortals, like me, will not be able to write it our
> understand it without undue effort.

I was actually referring to the details of the current presentation 
syntax rather than its existence.

We already have short form presentation syntaxes for several primitive 
literal types so having a custom presentation for text, e.g. 
'lexical'@lang, seems reasonable to me and avoids encoding the lang as 
part of the lexical form.

Dave
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Received on Monday, 24 September 2007 21:44:20 UTC