Call Back information

["Jon Paris" <Jon.Paris@xxxxxxxxxxxxxx>]

 >> Usually when you call a routine in a service program, you want the next
line of code to be able to detect an error.   You don't want some external
procedure being called...

Actually I kinda like it for just that purpose Scott.

The main line calls a generic routine to perform some processing.  Some of
the potential "errors" that can be signaled by that routine are not errors
to the caller - they are perhaps an expected condition (like "not found"
when I'm adding a  new record).  Using a call back approach one generic
routine can do zero error handling (Proc ptr is passed as null) - generic
error handling (proc pointer not passed at all) or caller specific/extended
error handling (proc ptr is passed).  The proc doesn't have to be external -
it can be local to the main line.


Jon Paris
Partner400