Re: Glossary entry: Abstract syntax

On Mar 8, 2007, at 9:38 PM, Gerd Wagner wrote:

>
>> A syntax must account for how statements in a language
>> are going to be specified, and need not account for things
>> that are implied (ie not explicit) in the syntax.
>
> Sure, that's what you can do using MOF/UML metanodels.
>
>> A meta-model as a model of a modeling language must account for all
>> the things in a language that matter to tools, and need not account
>> for everything in the syntax.
>
> That's not true, I can't follow you. If you make a metamodel
> to define a language, then you account for everything in the
> (abstract/conceptual) syntax.
>
>> In syntax, you must be concerned with
>> how a sort is defined.  In a metamodel, you don't need to represent
>> that (you CAN, of course), but you must represent that a language
>> element has a sort.
>
> No, you need not represent that for constructs for which the
> syntax does not require it. In a rule metamodel a function
> need not have a sort. It will have a sort, though, in the
> underlying vocabulary metamodel (which you still miss to
> discuss, btw).
>
>> The problem with using a metamodel as an abstract syntax is that you
>> must identify the parts of the model that don't actually have a
>> syntactic construct.
>
> Again, I can't follow you.
>
>> So the UML diagrams you see for RIF are to be interpreted as visual
>> representations of the syntax, such that a subclass is a syntactic
>> disjunction an aggregation is syntactic concatenation, and
>> multiplicity on aggregation is repetition.  The tools that will
>> generate the XML and BNF syntax specifications for RIF from the asn06
>> will use that assumption.
>
> So, was there any decision to use Sandro's experimental "asn06"?
> What about the objections of Francois, and my suggestion to use
> the more mature framework of KM3/ATL? Are they just ignored?
>
> -Gerd
>
>

Received on Thursday, 8 March 2007 21:48:30 UTC