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Re: CORE: nascent issues list

From: Dave Reynolds <der@hplb.hpl.hp.com>
Date: Sun, 17 Aug 2008 10:18:22 +0100
Message-ID: <48A7ECDE.4070703@hplb.hpl.hp.com>
To: kifer@cs.sunysb.edu
Cc: RIF WG <public-rif-wg@w3.org>

Michael Kifer wrote:
> 
> 
> On Fri, 15 Aug 2008 16:07:45 +0100
> Dave Reynolds <der@hplb.hpl.hp.com> wrote:
> 
>> (c) some genSym builtin
> 
> Just 0.02c: this cannot be in the Core or in BLD.

Surely it could if it was deterministic (in which case genSym is not a 
great choice of name). Perhaps something like:

"""
func:genSym

(?arg1, ... ?argn;  func:genSym(?arg1, ... ?argn))

Generates and returns a constant uniquely determined by the values of 
the n arguments. This constant takes the form:
    "gensym:ID"^^rif:local
where ID is a string uniquely determined by the values of the arguments 
?arg1 through to ?argn. For example, this might be a digest of the 
concatenation of the canonical lexical forms for each argument.
"""

Thus to use it to generate skolem constants the rule author would need 
to explicitly include a rule identifier and the values of the 
universally quantified variables in the set of genSym arguments.

Would something along those lines be reasonable?

Dave
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Received on Sunday, 17 August 2008 09:18:50 GMT

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