what is object oriented programming

... and how does it relate to the rpg programmer.

An rpg data struct is an object.  When the data struct is declared LIKEDS
another struct, the programmer is instantiating the LIKEDS struct.

A proc whose function is to perform some action on a data struct is an
object oriented proc.

So the following is object oriented programming, rpg style:

** the order struct template
d tp_order          ds                    qualified
d  CustNbr                        7a
d  OrderNbr                       7a
d  QtyOrdered                     7p 0
d  QtyShipped                     7p 0

** instantiate the order struct
d order             ds                     likeds(tp_order)

** ------------------------  order_Init -----------------------------
** order_Init - initialize the order struct
d order_Init        pr
d  OutOrder                                likeds(tp_order)

** -------------------------- order_Print ---------------------------
** order_Print - print the order
d order_Print       pr
d  InOrder                                 likeds(tp_order)

 /free
  // initialize the order object
      order_Init( order ) ;

  // print the order object
      order_Print( order ) ;
 /end-free

The only difference between this and C++ is the placement of the name of the
object.
   rpg:   order_Print( order ) ;
   c++:   order.Print( ) ;

heresy?

-Steve Richter