Re: XForms Basic and Schema Validation

Hi David and Henry,

Just want to make sure you both take note of [1].

I believe that Mark's contention that the term datatype is perhaps being 
misused in the XForms spec
is likely due to the incorrect conclusion that what a datatype is and how 
it is expressed were one
and the same thing.

The use of the term datatype is deliberate because the most important use 
case for XForms 1.0
that has been discussed at many face to face meetings is vcharacter data 
validation, which corresponds
to direct user input.

So, yes, in answer to your final question, what I have been saying in 
numerous posts is that
the type MIP of XForms is for associating a datatype and therefore 
corresponds to datatype
validation, even if the datatype association was made based on a datatype 
obtained from
a complex type.

[1] http://lists.w3.org/Archives/Public/www-forms/2006May/0075.html

Cheers,
John M. Boyer, Ph.D.
Senior Product Architect/Research Scientist
Co-Chair, W3C XForms Working Group
Workplace, Portal and Collaboration Software
IBM Victoria Software Lab
E-Mail: boyerj@ca.ibm.com  http://www.ibm.com/software/

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





David Landwehr <david.landwehr@solidapp.com> 
Sent by: www-forms-request@w3.org
05/09/2006 01:37 PM

To
"Mark Birbeck" <mark.birbeck@x-port.net>
cc
<www-forms@w3.org>, <ht@inf.ed.ac.uk>
Subject
Re: XForms Basic and Schema Validation







Hi Mark,

You have done a good job of describing this issue and have had a lot 
of patience with me. I admire the amount of work you have put into 
explaining this and you have done a good job. Combined with the mail 
from Henry I do believe i'm finally on the same page.

 From Henry's mail it seems like XForms might have used the term 
datatype intentionally for defining the validity. I have always 
thought of section 5.1 as one describing the use of the XML Schema 
components (complex and simple types) and this is the root of every 
misunderstanding I have had.

Do you believe that the use of the term datatypes in 5.1 means that 
XForms only has to perform this datatype validity check when applied 
from bind/@type ?

Best regards,
David

Den May 9, 2006 kl. 9:00 PM skrev Mark Birbeck:

>
> David,
>
>> Okay.
>>
>> Please take a look at this:
>> <complexType>
>>       <simpleContent>
>>         <extension base="integer">
>>           <xsd:attribute name="test"  type="integer" use="required"/>
>>         </extension>
>>       </simpleContent>
>>     </complexType>
>>
>> We agree that this is a complex type with simple content.
>
> Yes, definitely.
>
>
>> When Henry wrote: "The validation semantics of (1) --
>> (3) are all defined in terms of properties of the
>> corresponding datatype.", I toke that as this complex type
>> would be regarded as a datatype which can be a mistake from
>> my part.
>
> So, in your example above the 'integer' datatype would be used for the
> *content* of @test, as well as the *content* of whatever element 
> you apply
> this complex type to. These two applications of 'datatype' 
> correspond to
> points (1) and (3) in Henry's list, and in my reading of his reply 
> to you I
> think it was these various uses that he was getting at.
>
>
>> Henry, could you clarify if the above type definition would
>> qualify as being name a datatype or should it be named a
>> complex type with some simple content which is a datatype?
>
> Pretty much the latter...although in my understanding of 'simple 
> content',
> it is 'datatype plus attributes'. In other words, simple content is 
> the
> combination of some element content *and* possibly attributes, and 
> it's the
> *content* of the element that is a simple type.
>
>
>> Maybe the term datatype cannot be used in XForms as it is today, e.g.
>> maybe datatype is not an actual component you can reference?
>
> I think it *is* something we can reference in the XForms spec, 
> since the
> term is used all the way through the second part of XML Schemas. 
> But I think
> it has been used incorrectly in too many places so far, so we'd 
> need to all
> be in agreement on the terminology before we then went back and 
> worked out
> what was actually meant.
>
> The term that XML Schema uses when it doesn't care if something is 
> a simple
> type or a complex type is just 'type' or 'defined type'. Otherwise, 
> if you
> want to talk about a 'type' that is the 'stuff' that goes inside an
> attribute or inside an element (that is not nillable and doesn't 
> have child
> elements), then I think the term 'datatype' is perfectly fine.
>
> Regards,
>
> Mark
>
>
> Mark Birbeck
> CEO
> x-port.net Ltd.
>
> e: Mark.Birbeck@x-port.net
> t: +44 (0) 20 7689 9232
> b: http://internet-apps.blogspot.com/
> w: http://www.formsPlayer.com/
>
> Download our XForms processor from
> http://www.formsPlayer.com/
>
>
>