Re: Writing XML from RPGLE

On Fri, Aug 22, 2014 at 10:02 AM, Bradley Stone <bvstone@xxxxxxxxx> wrote:

On Fri, Aug 22, 2014 at 12:16 AM, John Yeung <gallium.arsenide@xxxxxxxxx>
wrote:

But his current concern is specifically XML (Excel .xlsx files)

I must have missed that. Seems rather proprietary, but still can be done
fairly simply with the template applications mentioned.

The current Microsoft XML-based formats (Office 2007+) are ostensibly open:

http://en.wikipedia.org/wiki/Office_Open_XML

It could be argued that Microsoft threw its weight around a bit
(deliberately or not; justifiably or not), but in the end, it's a
published standard, so in that sense, far less proprietary than "old
Microsoft" at least.

The thing with .xlsx is that, sure, it's XML-based, but as anyone who
has actually worked with it in earnest quickly finds out, the XML is
not the hard part. It's that the information is scattered all around
in various pieces. This is, in part, due to a certain amount of
holdover from the structural design of the older (and even more arcane
and opaque) .xls binary format. Some of the decisions Microsoft made
way back when were probably due to legitimate efficiency/space issues
(sharing strings and formulas where possible, for example), and cynics
could easily argue some decisions were made to ensure the format was
more proprietary and harder to reverse engineer.

In any case, what we're left with is not programmer-friendly, and the
characterization of "still can be done fairly simply with [various
template applications]" isn't one I subscribe to. I mean, the XML
part of it is quite simple, yes. At least as simple as any other XML
thing you're going to do. But .xlsx, well, more power to Vern, but I
would personally be looking harder for a pre-built package that
specifically handles Excel. And I know it has to be fast, so even
though there are excellent Excel packages for dynamic languages like
Python and Ruby, they don't fit the bill. Maybe for the writing part,
at least, Scott Klement might be persuaded to share what he's
developed so far with pure RPG. Short of that, my personal strategy
for this problem (i.e. essentially writing my own fast Excel library
if I can't find one) would be to try to translate some existing
dynamic-language Excel package (which almost by definition would be
open source) to RPG or C++.

John Y.