Why are xsd:duration and xforms:duration not supported/defined?

We seem to go out of our way in Section 5.1 (
http://www.w3.org/TR/xforms11/#datatypes-xforms) to not support the 
xsd:duration datatype.

There is even a NOTE saying that xforms:dayTimeDuration or 
xforms:yearMonthDuration should be used instead.

These are nice helper datatypes that have the advantage of not running 
into the confusion over how many days are in a month, but adding helpers 
should probably *not* get rid of the thing they're helping.  I think that 
is just being *too* helpful. 

In any case, it is difficult at best to claim that we don't support 
xsd:duration.   Anything that you can put in an xsi:type or in an XML 
schema can also be put in a type MIP, so type="xsd:duration" just works 
(in my software, at least).

Moreover, if I generate a form from a schema, and a data node has type 
xsd:duration, there is really no choice but to fill that data node with a 
value which conforms to xsd:duration, yet we're essentially saying that I 
could not create that same form without a schema?  Makes no sense.

Since this all "just worked" for me, I actually discovered this while 
trying to figure out why type="xforms:duration" MIP assignment wasn't 
working.  I expected to be able to get a duration or empty string, but 
xforms:duration is undefined, due only to the spec.  I think it should 
just work too.

1.1 Errata?  Could be optional, then scaled up to recommended or required 
in 1.2.

Cheers,
John M. Boyer, Ph.D.
STSM, Lotus Forms
Workplace, Portal and Collaboration Software
IBM Victoria Software Lab
E-Mail: boyerj@ca.ibm.com 

Blog: http://www.ibm.com/developerworks/blogs/page/JohnBoyer
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