Tip when v6 code can be reused

In version 7 programming, you might call existing version 6 subprograms that do not handle user interfaces. Be careful as this can be done only if the following rules apply on the subprogram you want to use.
* It does not use [M] classes.
* It does not use global variables.
* It does not use 'clalev' function.
* It does not have an interaction with the UI.
* It does not manage logical lock.
* It does not access parameter values with the 'AFNC.APARAM' or 'AFNC.APARAMUTI' functions.
* It calls only subprograms that follow the same rules.

If this is not the case, then you have to rewrite your subprogram. It can be quick if the rules that are not fulfilled are simple to fix.