You might be interested in 

http://www.idealliance.org/proceedings/xml04/papers/111/mhk-paper.html

to see how far this kind of approach can take you. What you are proposing is
much simpler. As you say, it could be done in a variety of ways, but it's
certainly not overkill to use XSLT for this.

Michael Kay
http://www.saxonica.com/ 

> -----Original Message-----
> From: Karr, David [mailto:david.karr@xxxxxxxx] 
> Sent: 28 April 2006 22:09
> To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
> Subject:  Is this strategy for runtime fixed-width->xml 
> conversions worthwhile?
> 
> I'm wondering about viable strategies for runtime conversion 
> of fixed-width messages into XML (and back, I suppose).  I 
> know there are various frameworks that do this, but it 
> occurred to me this could be done entirely with XSLT.
> 
> The stylesheet would have a single template element, which 
> would cover the entire message format (unless there are 
> conditional pieces).  The input to the stylesheet could be 
> empty, and a single stylesheet parameter would be the "input" 
> to the stylesheet.  Each reference in the template to the 
> input would use the "substring()" function, to pull the 
> appropriate portion of the parameter into the element.
> 
> I'm not sure exactly how the reverse direction would work, however.
> 
> Is this approach at all worthwhile?  What are specific 
> problems with this idea?