Outline the program control structures and conditional logic used in RPG programming.

In RPG (Report Program Generator) programming, various program control structures and conditional logic constructs are used to control the flow of execution and make decisions based on certain conditions. These structures and constructs help in creating flexible and efficient RPG programs. Let's outline some of the key program control structures and conditional logic used in RPG programming:

1. Sequential Control:
Sequential control structures allow the program to execute instructions in a sequential order, one after the other. RPG programs follow a top-down approach where instructions are executed line by line unless specified otherwise. The program control flows from one statement to the next until it reaches the end or encounters a branching or looping construct.
2. Branching:
RPG provides branching constructs that allow altering the flow of control based on specific conditions. The commonly used branching constructs include:

* IF-ELSE-ENDIF: The IF-ELSE-ENDIF construct is used to evaluate a condition and perform different actions based on the result. If the condition is true, the statements within the IF block are executed; otherwise, the statements within the ELSE block (if present) are executed.
* SELECT-WHEN-OTHER: The SELECT-WHEN-OTHER construct is used to perform multiple conditional checks. It allows specifying multiple WHEN conditions and their corresponding actions. If none of the WHEN conditions are met, the statements within the OTHER block (if present) are executed.
* GOTO: The GOTO statement allows jumping to a specific label or line number in the program. However, the usage of GOTO statements is generally discouraged in modern programming practices due to its potential for making code difficult to understand and maintain.
3. Looping:
Looping constructs in RPG enable executing a block of code repeatedly until a specified condition is met. The commonly used looping constructs include:

* DOU (DO Until): The DOU construct repeats the execution of a block of code until a specified condition becomes true. The condition is evaluated at the end of the loop.
* DOW (DO While): The DOW construct repeats the execution of a block of code while a specified condition is true. The condition is evaluated at the beginning of the loop.
* FOR: The FOR loop allows iterating over a specified range of values. It provides a convenient way to perform a specific action a predefined number of times.
4. Exception Handling:
RPG provides exception handling mechanisms to handle exceptional situations or errors that may occur during program execution. Exception handling constructs include:

* MONITOR-ON-ERROR: The MONITOR-ON-ERROR construct is used to capture and handle runtime errors. It allows monitoring a specific block of code and executing error-handling logic if any errors occur within that block.
* ON-ERROR: The ON-ERROR construct is used to handle specific errors by providing custom error-handling logic. It allows catching specific error conditions and executing appropriate actions.

These program control structures and conditional logic constructs in RPG provide the flexibility to make decisions, control the program flow, and handle exceptional situations effectively. By utilizing these constructs, RPG developers can create robust programs that handle different scenarios and produce desired outcomes.