W3C home > Mailing lists > Public > public-forms@w3.org > December 2007

Re: A decimal-string() function proposed for XForms 1.2

From: Ulrich Nicolas Lissť <unl@dreamlab.net>
Date: Wed, 12 Dec 2007 23:14:41 +0100
Message-ID: <47605D51.3090001@dreamlab.net>
To: Erik Bruchez <ebruchez@orbeon.com>
CC: "Forms WG (new)" <public-forms@w3.org>


I was just writing a response along similar lines like Erik's one ... So
just a short cut.

I don't see much value in adding more functions in general and in adding
a decimal-string() in particular. There is no decimal-string() in XPath
2.0 (Nick ?). Instead, format-number() is there and is more powerful. It
is actually an XSLT 1.0 function and if we really want this, we could
"borrow" it like we did with current().

However, we have the extension function mechanism and it should
therefore be easy to include any function for specific business reasons.


Erik Bruchez wrote:
> My reaction to this will be the same as always: more custom functions ==
> bad ;-)
> But if we *have* to have such a function now, there is no doubt in my
> mind that we must then integrate the XSLT 2.0 format-number() function.
> While we are at it, integrate format-date() as well. The XSLT 2.0 group
> already did the work for us so there is no need to reinvent anything.
> Orbeon Forms already provides these two XSLT 2.0 functions it its XPath
> function library, because, well, there is just no way not to have them.
> On this point, I definitely agree with you: it is a very important
> feature to have. But we don't have to invent it ourselves.
> A side note: I understand the argument about "waiting" for such and such
> features. There are lots of features that are currently not in XForms
> 1.1 and without which Orbeon simply can't live, including XPath 2.0,
> dialogs, HTML text areas, and so on. I am sure every implementor can
> come up with a series of such features, and unfortunately it may not be
> possible to rush them all in at the same time as our resources are limited.
> But implementors don't have to wait: they can implement extensions to
> XForms as they see fit. This is very positive as it provides the Working
> Group with real implementation experience, which is then leveraged to
> define a standard.
> -Erik
> On Dec 12, 2007, at 11:31 AM, John Boyer wrote:
>> Hello all,
>> One of the small features I proposed for 1.2 is a decimal-string()
>> function that can convert an XPath 1.0 number to a lexical string
>> representation that is desired by financial industry application
>> developers.  Nick comments that we'll get this in XForms 2.0 when we
>> have XPath 2.0.  For my own part, I wouldn't want to wait that long
>> for XForms to 'officially' support financial applications.
>> I think it is not hard to have a function that receives a number and
>> an indication of how many places past the decimal point it should be
>> rounded to obtain a string output.  The only extra bell/whistle would
>> be to indicate whether or not zero padding is desired, which is often
>> done with a negative sign or some such.
>> The lion's share of usage will be of the form
>> decimal-string('12.300000002', -2) to get a guarantee of two decimal
>> places, with zero padding if needed. The output in this example would
>> be the string '12.30'.
>> Right now, the numeric results of calculations come out to irritating
>> values when converted to lexical representation for storage in XML,
>> and it becomes necessary to write code on the server side to fix this
>> stuff up before it goes into a database.  I do have actual customers
>> now for whom I am currently having to add an extension function
>> because the XML data we send chokes their database, and they don't
>> want to add code, esp. since it is contrary to our "killer app"
>> messaging.
>> Now that there is some discussion on it, it seems worth breaking out
>> into a thread of its own to see if
>> A) there are any other objections
>> B) to see if I've managed to convince Nick yet :-)
>> Cheers,
>> John M. Boyer, Ph.D.
>> Senior Technical Staff Member
>> Lotus Forms Architect and Researcher
>> Chair, W3C Forms Working Group
>> Workplace, Portal and Collaboration Software
>> IBM Victoria Software Lab
>> E-Mail: boyerj@ca.ibm.com
>> Blog: http://www.ibm.com/developerworks/blogs/page/JohnBoyer
>> Blog RSS feed:
>> http://www.ibm.com/developerworks/blogs/rss/JohnBoyer?flavor=rssdw
> -- 
> Orbeon Forms - Web Forms for the Enterprise Done the Right Way
> http://www.orbeon.com/

Ulrich Nicolas Lissť
Received on Wednesday, 12 December 2007 22:15:29 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 19:48:27 UTC