Question about using constant variables in Forms

Question

As I am still very new to Forms, please forgive my ignorance if the answer to my question is very simple. I am trying to figure out how to use constant variables within my Forms application. For example, if I want to setup return code constants for the application (mind me, these are examples):
RC_SUCCESS CONSTANT PLS_INTEGER := 1;
RC_FAILURE CONSTANT PLS_INTEGER := 0;
RC_YEAR_DATA_NOT_FOUND := 50;
Then in a module I created, if I wanted to check the return code against one of the constants I would do:
DECLARE
rc PLS_INTEGER;
BEGIN
GET_YEAR_DATA('2000', rc);
IF rc = RC_YEAR_DATA_NOT_FOUND THEN
-- Do some error handling
END IF;
END;
I know that you can declare constants within individual procedures or packages but I can't see to find information on how to do this globally for the application. I've read about using global variables within Forms but the CHAR data type only and the fact the value can be changed doesn't really fit for this purpose. Am I missing something? Is there a config file or something for the webserver that can be used to set these up??
Any help would be appreciated.
Thanks

Answer 1

To declare constants create a Package-Specification in a pll and deifne all your constants there, something like:
PACKAGE PK_CONSTANTS IS
  RC_SUCCESS CONSTANT PLS_INTEGER := 1;
  RC_FAILURE CONSTANT PLS_INTEGER := 0;
  RC_YEAR_DATA_NOT_FOUND := 50;
END;Then attach that pll to all your forms-modules, and use it like
IF rc = PK_CONSTANTS.RC_YEAR_DATA_NOT_FOUND THEN
END IF;A word about exceptions or errors: In my eyes its clearer (and in case of exceptions even better) to raise an exception than to hide it behind return-codes.