Re: [TED] Question on constraints

Christian,

I am not sure I understand exacty what your point is.

-hak

Christian de Sainte Marie wrote:

> Hassan Aït-Kaci wrote:
> 
>>
>> (3) other data models may be accommodated using this "data model as
>>     constraint system" paradigm and conjugated with definite clauses
>>     using the CLP scheme in order to obtain Horn-like rule systems
>>     over varied data types (e.g., Java, C#, or C++ classes/objects).
>>
> 
> We agreed that RIF would specify a common expression language from which 
> the various RIF dialects will draw (by restricting which expressions are 
> allowed in the LHS/condition, RHS/conclusion, and constraint expressions 
> [1]).
> 
> [1] E.g., CORE will probably allow only a conjunction of atoms in the 
> body and a single atom in the head.
> 
> Don't we need to associate constraints to said language expressions, 
> instead of at the rule level only (as we discussed and decided at F2F4), 
> if we want that good property of data model abstraction brought by the 
> constraint paradigm to apply to the ground arguments and locally bound 
> variables in the expressions?
> 
> If not, how comes that we do not need to abstract the data model in 
> order to agree on the semantics of expressions in the expression 
> language, but we need it for rules (or that the abstraction can be 
> implicit at the expression level but not at the rule level)?
> 
> Christian
> 
> 
> 


-- 
Hassan Aït-Kaci
ILOG, Inc. - Product Division R&D
tel/fax: +1 (604) 930-5603 - email: hak @ ilog . com