RE: OO in RPG

[Joel Fritz <JFritz@xxxxxxxxxxxxxxxx>]

I actually reviewed the state of the thread before responding.  I agree that
ILE provides some things that are associated with OO, but I also agree with
Hans that RPG isn't ideal.  IMHO what you can do is:

Encapsulation:  You probably already do this with subroutines and dynamic
calls, but if you use sub procedures and service programs, you get better
protection against side effects from the use of global variables and forced
passing of parameters by reference.

Abstract data types and true objects:  You can't really do it, but service
programs can give you some of the features of an object.  Maybe someone else
has figured out a way to do it, but the sticking point is multiple instances
of the same object. 

Polymorphism:  You can't really do it, but you can do some things with
argument lists and operational descriptors that give you some of the same
thing with a lot more work.  

Inheritance:  Nope.

Another question, probably good for a Friday, is how useful is the object
oriented model?  I like it as a way of approching problems, but has it
revolutionized application development the way people thought it would ten
years ago, or so.  I seem to remember predictions of a whole new class of
programmers who would build applications from "boxes" of components and
write almost no code except to pass messages back and forth between the
components--all drag, drop, and connect the dots.  

> -----Original Message-----
> From: Alistair Rooney [mailto:alistairr@tbsa.co.za]
> Sent: Friday, December 01, 2000 12:34 AM
> To: AS400 Listserv (E-mail)
> Subject: OO in RPG
> 
> 
> Does anyone have any ideas (Brad Stone, Joe Pulta, Hans 
> Boldt) how to write
> RPG code in a way that simulates an Object Orientated approach?
> 
> TIA
> 
> Alistair Rooney
> Software Engineer
> Tibbett & Britten Africa
> +27 31 2047701
> 
> A lottery is just a tax on people who are bad at math
> 
> 
> 
> 
> 
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