Re: Write to a XML document

I'm having difficulty understanding why we don't just write directly to
XML. Something to do with validity checking.

Not knowing the details, validity checking most likely has something to do
with XML Schema Definitions (XSD's) which are used to dictate relationship
structure and allowable field content (i.e. only allowing an int in an order
number field) among other things.

As Aaron said, this is a 'sanity check' sort of thing to ensure that your XML is well formed; that each <start> has a corresponding </start> and the contents are sane too (no CHAR in a NUMBER field, etc. Having a converter create genuine XML out of pseudo-XML is one way to help ensure that the resulting XML is well formed.

That doesn't mean that you can't emit well formed XML from your RPG code. If you are careful, you can certainly emit XML that passes any sanity check with flying colours.

Although I got some heat over it, I wrote an XML emitting application entirely in native RPG, writing directly to an IFS stream file. I was able to sanity check the data before it went into the XML file and produce a 'data elements in error' report that mapped back to our application database elements. That's pretty hard to do using an external validator.
--buck