On Mon, 6 Jun 2011 15:53:51 -0400, Ray Denenberg, Library of Congress wrote
> From: Bruce D'Arcus
> > One way to slice the levels is how different feature diverge from the
> > base. For example, a standard range of "2002-02/2002-03" is not
> > supported by Level 0, but it's components are.
> That's a disturbing observation as I suppose I didn't realize that 8601 
does not support "2002-02/2002-03". Thus features 208-211, which are 
represented as being 8601 conformant, aren't.

I only have a copy of the 2000 draft.. but.. defines these truncated dates. 
5.5.1 gives pattern a) as an interval: start/end where start and end are 
Since the terms "truncated representation" is used in this section there is 
no reason to assume that one their intent was not to allow for the use 
truncated representations for start and end. While 5.4.1 is specified for 
date it was I think an oversight.
I think we should "fix" this oversight and allow for start/end where start 
and end are ISO8601 dates (including truncated representations) in any 
minimal level--- I will assume that most people's implementations of 8601 
have been doing this the whole time anyway.

> ISO 8601 is a horribly frustrating document to try to make sense out. It 
makes no common sense to me why 8601 wouldn't want to support "2002-02/2002-
03"; I can see that it doesn't, but only by the lack of an example to the 
contrary. (At least as far as I can tell - and given 8601's general lack of 
examples, deciphering it based on [UTF-8?]it’s examples is not a 
comforting process.)

No. It clearly says in that intervals defined with start/end use 
5.4.1. It does not explicitly, however, disallow 5.4.2. (reduced 
representations) but does not explicitly allow them either. I see this as an 
oversight. Should reduced representations not have been desired they would, 
I think, have been explicitly disallowed.

> But I digress.  If "2002-02/2002-03" is not a valid 8601 string while 
both "2002-02" and  "2002-03" are, then I agree that it does make sense to 
cast "2002-02/2002-03" into level 1 rather than level 2. On the other hand, 
that seems to be the only feature that would fit this criterion and all else 
would be cast into level 2, which would make level 1 rather slim.
> --Ray


Edward C. Zimmermann, NONMONOTONIC LAB
Umsatz-St-ID: DE130492967