Re: Creating XML document via SQL - Db2 for i 7.2

Hi John,

Modular is a better term, I agree.

RPG capabilities are sufficient to simulate basic objects. I could
simulate instantiating an object, with properties (fields) to retain state,
complete with property get and set methods, methods (procedures) to provide
behavior, and constructor and destructor methods to initialize and destroy
state.

RPG can do a semi-decent job supporting encapsulation.

RPG capabilities are not sufficient to efficiently simulate OOP abilities
like reflection (impossible), inheritance, composition, polymorphism, and
abstraction (all not impossible but extremely difficult to simulate).

My point is a simple one. In RPG you can simulate basic objects, but
anything beyond that is either impossible to simulate, or so laborious that
it would never make economic sense to do.

If someone were to try to simulate the advanced capabilities of OOP in RPG,
they'd be missing the entire point of OOP, which is other re-using other
people's languages and objects that have already provided those solutions.
One would be recreating the wheel.

Since ILE C++ is supported on the IBM i, I doubt there is anything missing
in the foundations of ILE to support OOP. The limitation is not ILE, but
the language used on top of it.

Mike

On Sat, Mar 10, 2018 at 3:25 PM, John Yeung <gallium.arsenide@xxxxxxxxx>
wrote:

On Sat, Mar 10, 2018 at 3:38 PM, Mike Jones <mike.jones.sysdev@xxxxxxxxx>
wrote:

Honestly, most OOP programmers don't know much at all about RPG or RPG
service programs, and most RPG programmers don't know much at all about
OOP. Hence, in most cases their opinions are uninformed ones.

Fair enough, but the ILE model of modules, service programs, and
executable objects is very strongly reminiscent of the classic
C-oriented model of program development, and no one in the OOP
community would seriously call that model "object oriented". My point
being: sure, OOP folks don't know about RPG. Pretty much nobody
outside the midrange community knows about RPG. But OOP folks ***do***
know about C. Part of the whole reason for the existence of OOP was to
go beyond what is natural to do in C. And I can tell you that RPG is
basically in the same category, computer-science-wise, as C. And
neither RPG nor C are object oriented to any meaningful degree,
according to what OOP practitioners would consider "object oriented".

I do consider service programs object oriented, but just not as flexible

as

the capabilities of a language like Java or C#.

As I said before, I don't want to deny you your opinions. But this way
of using the term "object oriented" is really not compatible with how
most people use the term. You would be better understood by
programmers at large if you used the term "modular" for what you are
describing.

John Y.