Re: local arity, term WFF-ness conflicts with merging requirement?

Hello Dan
 
In BLD, pred and funcs have one arity, and it is correct that the
restriction holds even across multiple documents. So the requirement is met
-- rulesets can be merged -- but if one ruleset is in error, then the merged
version will be able to detect the error.
 
- Adrian
 
 
From: Dan Connolly <connolly@w3.org
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Date: Mon, 05 May 2008 14:35:07 -0500


To: public-rif-comments@w3.org
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Message-Id: <1210016107.4651.363.camel@pav.lan>
 
I noted these two bits of the RIF syntax:
 
"Each predicate and function symbol has precisely one arity"
 
"A well-formed term is one that occurs in a well-formed set of fomulas."
 
  -- http://www.w3.org/TR/rif-bld/
 
Those seem to be not web-wide definitions, but definitions
that just apply to one file or something. Otherwise,
to take an arbitrary example, the function symbol ABC:
what is its arity?
 
The context-sensitivity of those definitions seems
to conflict with the requirement to be able to
merge rule sets:
 
"4.2.12 Merge Rule Sets 
RIF should support the ability to merge rule sets. "
http://www.w3.org/2005/rules/wiki/UCR#Merge_Rule_Sets
 
If ABC has arity 2 in one rule set and arity 3 in
another, what happens when those rule sets are merged?
 
Is it worthwhile making the requirement more precise as follows?
 
  any collection of well-formed RIF formulas is itself well-formed
 
-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/
gpg D3C2 887B 0F92 6005 C541  0875 0F91 96DE 6E52 C29E