RE: [ubl-dev] Simpler-Than-UBL Design Rules

["David RR Webber \(XML\)" <david@drrw.info>]

Steve, 

On Xpaths - yes - of course you can use the full XPath - just check the
checkbox on the entry control  (Martin also has this all demo'd in the
new tutorial part 2 from the website). 

The other aspects you mention - codelists, and use of XPath to control
when certain validations apply - yes CAM does this - you can see this
at work in the order and invoice templates where the Xpath /* child
referencing causes one CAM function to reference content whereever it
is in the template...and then you can do specific overrides to exact
XPaths.

Good to know your rationale behind XForms (was wondering about that). 
The better AJAX implementations are using XML control file(s) to
configure the form and controls and validations.  Autogenerating that
control XML is the identical method to XForms using the xsd... some
more comments inline below. 

Cheers, DW 


"The way to be is to do" - Confucius (551-472 B.C.)
 

 -------- Original Message --------

I've thought a bit about using AJAX but that would
seem to be a backward step:
>> (yikes!  the industry is betting on AJAX - and I 
 personally love it because of its open layered model!)

firstly, no advantage I'd have thought on the client
side as there is no assertion that the client forms
processor (browser only I should think with AJAX) has
a built-in means of validating against any kind of schema
>> some AJAX tools allow xsd to be used to create default 
   validations - but yes - then AJAX has ability to load
   from an XML control file the validation rules

secondly, no built-in facilities for avoidance of script,
declarative programming, framework for good practise,
or nice way of doing repeats
>> ??? Yikes! I do believe AJAX does all of this!

thirdly, the requirements of customisation and context
are such that it seems preferable to use schema-driven
code generation to allow changes to schemas (or models
if you prefer) to be rippled in a CASE-like way into
the form - not sure you can reliably do this with AJAX
as it seems you can with XForms.
>> If the CASE tool is re-generating the XML control
   files that the AJAX loads - then I believe "Yes" 
   it can support this.

fourthly, I've come across converters from XForms to
AJAX but not the other way so I'd prefer to start with
the XForms which * can * it seems be schema-driven and
optionally generate the AJAX or whatever - which might
answer some of the above to some extent (yet to look
into that thoroughly though)

>> I'm thinking that a generic CAM-based "generate"
   method should work for both - since the principles
   are identical - just the XML-syntax used is the 
   varient - e.g. "dialects" - while the xhtml is a
   common rendering...

We will have to experiment with all this over the next
few weeks.  I agree your XForms samples provide a nice
initial set of target samples to replicate...