[sc34wg3] Unique names in Draft Reference Model

[Anthony B. Coates]

** Reply to message from "Steven R. Newcomb" <srn@coolheads.com> on 30 Dec 2002
21:04:12 -0600

> Here's an equally good question: Why shouldn't they
> share the same namespace?  What's the advantage of
> having separate namespaces for these things?  Would the
> advantage of making separate namespaces outweigh the
> disadvantage of having to invoke the right one them
> whenever referring to a property, or an assertion type,
> or a role type?  I think that having separate
> namespaces would require all of these identifiers to
> have three fields.  Isn't a TM Application likely to be
> more robust, and less prone to errors and
> misunderstandings, if everything is required to have a
> unique name?

No, I don't think so.  Over the holiday period, I've been analysing the RM to
produce a UML model, and a logical (relational) database model.  Not quite
finished yet, but based on this analysis, I cannot see a situation where it
would be a problem to allow a property to have the same name as an
assertion/role type.  I'm less sure about whether assertion/role types might be
subject to confusion.

>From the point of view of writing an application, every field in every class
effectively defines a separate namespace for values, so separating namespaces
is not an issue, it is just normal practice.  However, if property names have
to be distinct from assertion/role type names, that adds a layer of
cross-checking which is a burden on the application.  My point is that I don't
see any gain as a result of that burden, which makes me think it is
unnecessary.  I would suggest that properties, assertion type names, and role
type names should have separate namespaces until such time as someone can
identify a situation where having the same name leads to an unresolvable
ambiguity.

	Cheers,
		Tony.
====
Anthony B. Coates, Information & Software Architect
mailto:abcoates@TheOffice.net
MDDL Editor (Market Data Definition Language)
http://www.mddl.org/
FpML AWG Member (Financial Products Markup Language)
http://www.fpml.org/