count on cascading deletes

Dear All

prior to issuing a cascading delete in an interactive program
I would like to retrieve from Postgresql what is involved in the
particular delete, so that this can be printed to the console
and the user can be asked:

   This is what your delete would do in the database:
   deleting panel = 123 would imply deleting the following children:
                  in foo: 123    records
                  in fuu: 123456 records

   do you really want to do this? (y/N)

As this is a general problem, I would assume, that someone has written
a function that would do that. Unfortunately, no luck with google.

Thanks in advance

Tred