Don't much like doing the processing with the dialog ON, so I prefer (exit).
What processing?
The programs operate in much the same way, with the evaluation ceasing if the criteria for the dialog loading successfully is not met. Only, at this point, your code will force an error using (
exit), whereas my code will exit cleanly without error - I see no argument for using (
exit).
I would get rid of the progn and move the printing of results outside.
Why? I see no reason to do this - on the contrary, this adds redundancy to the code as there is no need to test whether
itm is defined if the
princ expression is included within the 'then' argument for the
if function.