Annotations that aren't safely ignored (was Re: How to specify OWL version in a document)

On Jun 23, 2015 11:22 AM, "Bijan Parsia" <bijan.parsia@manchester.ac.uk>
wrote:

[Taking you not *quite* out of context]

> Having annotations that have an effect in some cases but not in others
seems sorta dangerous.

Like ic:imports? :-) [1]  Or trowl:Nbox? [2]

There are already cases where annotations are used as more than simple
metadata.

Many protocols have ways to specify that certain extensions are mandatory,
so that if a message is received with an unknown, mandatory extension, an
error is signalled, with other unknown extensions simply ignored.

Maybe we could use annotation prop... oh, right.

One convention that might work would be to use a faux property (e.g.
kludge:isKnownMagicAnnotationProperty) for such mandatory annotation
properties, and make contradictory positive and negative assertions about
the property.

Tools that know the right magic can discard these assertions; tools that
know about the convention can signal a useful error; tools that do not know
about the convention can detect an inconsistency.

An alternative approach would be to use disjoint metaclasses to force
inconsistency (might give better error messages / faster failure for EL).

(There are also recommendations like SKOS that use annotation properties,
instead of data or object properties, for properties that are central to
the subject area. This is problematic for reasoners using the direct
semantics.)

Simon

[1] http://docs.stardog.com/icv/icv-specification.html#_2
[2]
http://trowl.org/documentation/using-local-closed-world-reasoning-in-trowl/