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1.1 FPWD: error in timeOnTimeline function

From: Dave Peterson <davep@iit.edu>
Date: Thu, 29 Jul 2004 11:14:19 -0400
Message-Id: <a0521060fbd2ec23d6039@[192.168.0.3]>
To: Schema IG <w3c-xml-schema-ig@w3.org>, www-xml-schema-comments@w3.org

Sandy Gao has pointed out that the timeOnTimeline function doesn't
behave correctly for date/time datatypes having forced-absent properties.

Specifically, what should happen is that the first six values (always
stored normalized to Z) should be denormalized to their local values
(previously called "raw" values), then the default values applied to
the absent ones, and finally the result renormalized to Z and the
calculation completed.  Mea culpa.

N.B.:  This may also be a problem with some other date/time functions;
I'll check at some point.

The various algorithms would be a lot less susceptible to this kind of
error (and would be for the most part easier to implement) if the
property values stored were the local values rather than the normalized-
to-Z values.  C'est la vie.  (Hint for implementers:  You aren't
required to actually store Z-normalized property values; you may find
it easier to store the local values instead.)
-- 
Dave Peterson
SGMLWorks!

davep@iit.edu
Received on Thursday, 29 July 2004 11:14:31 UTC

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