On Thu, Jan 12, 2017 at 8:30 AM, Jim Oberholtzer
<midrangel@xxxxxxxxxxxxxxxxx> wrote:
One thing that constantly flummoxes me is why folks think they cannot use
object oriented design and building techniques with IBM i even if they are
using RPG or even COBOL for that matter. I'm told RPG and COBOL are not
object oriented therefore the techniques won't work. Not true. What
Birgitta just described is an excellent, concise, and to the point
description of the modernization that needs to happen to many if not most
applications running on IBM i .
Jim, from what you've said, it's not clear to me whether "those folks"
are wrong or that you have misheard or misrepresented what they're
trying to tell you. It certainly could be both.
What is an indisputable fact is that RPG and Cobol are not suitable
for "object oriented programming". That is, the languages themselves
do not provide support for the specific programming paradigm currently
referred to as OOP. You could actually try to build up an ad-hoc OOP
system in RPG or Cobol (they are, after all, Turing-complete
languages), but it would be ridiculously complicated and not worth
anyone's time or trouble.
Now, I'm willing to allow that object oriented *design* could be
thought of as a bit of a different beast. They are kind of related in
the sense that good OOD is a hallmark of good OOP. But OOP is not
required for OOD. I'm confident that the *underlying* principles
behind OOD predate the term OOD itself, and certainly predate the
(current) understanding of OOP. Really, the core of what you're
talking about when you (Jim) say OOD is simply modularity. And that
fundamental concept has been around in programming since at least the
introduction of functions and subroutines. Maybe even before then.
Birgitta often uses the term "modularity" when she writes about
design. I think this is a better term to use for what you are talking
about, Jim. By now, OOD and OOP are pretty strongly linked in people's
minds and way of speaking (and in plenty of "official" definitions),
so if you talk about OOD, your listeners are going to naturally assume
you mean a design which leads eventually to implementation in OOP, and
I'm telling you, RPG and Cobol are simply *not* OOP languages. They
really are not. (Well, there have been object oriented extensions to
Cobol, but these never caught on, and are not what most people are
referring to when they say "Cobol".)
John Y.
midrange.com
