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Review of the n-ary extension

From: Boris Motik <boris.motik@comlab.ox.ac.uk>
Date: Tue, 7 Apr 2009 14:27:53 +0100
To: <public-owl-wg@w3.org>
Message-ID: <16F0D6594DBE4A108FE9FC14E59365AC@wolf>

Please find bellow my review of the n-ary extension. I've split my comments into
general and editorial ones.



General comments:

- I find the syntax such as leq(Arguments(x y) ( x y )) rather clunky: it first
defines the aliases x and y and then uses them in a restriction. This might be
avoided if we provided unique names for arguments in all restrictions. For
example, $1, $2, $3, etc. comes to mind. Under such an approach, one would
simply write leq( $1 $2 ). Such a syntax seems to be much more compact and
therefore easier to decipher (no extraneous parentheses).

- The domain of the operations such as * and + is unclear: is it owl:real only,
or does it include xsd:double and xsd:float as well? I believe it should be the
former and not the latter. But if this is the case, then NaN, +INF, and -INF
should not be mentioned any more as they were evicted from the value spaces of
the numeric datatypes recently.

- owl:realPlus should be replaced with owl:real.

Editorial comments:

- Throughout: After the last change to the way abbreviated IRIs are handled in
the FS, all such IRIs need to contain a colon. Thus, "water" should be changed
to ":water", and similarly for other IRIs.

- Section 1, 1st sentence: "types" -> "datatypes" or "data ranges". (At this
point, it is unclear what "types" might be.)

- Throughout: "data predicates" -> "data ranges".

- Section 1: "These predicates can be in OWL axioms" -> "These predicates can be
used in OWL axioms"

- Section 1: "Predicates can only related values data properties" -> "can only

- Section 1: "in future documents" -> "in future versions of this specification"

- Throughout: The usage of the royal "we" seems inappropriate to me in a
specification such as OWL. Sentences such as "With this definition, we can
infer:" should be rephrased as "With this definition, one can infer:"

- Throughout: It seems to me that the style of presentation should be more
matter-of-fact. Hence, sentences such as "All we need to specify here is what
the meaning of a Comparison, ScaledComparison, and LinearComparison is." should
be rephrased as "This document just defines the semantics of Comparison,
ScaledComparison, and LinearComparison."
Received on Tuesday, 7 April 2009 13:29:05 UTC

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