unnest

Attached, array -> rows iterator.

select * from unnest(array[1,2,3,4,5]);

Unnest
---------------
1
2
3
4
5
5 rows

The switch statement could probably be done in a different way, but
there doesn't seem to be any good examples of how to return anyitem. If
anyone have a better way, please let me know.

Does anyone know how to check individual array elements for NULL values?
PG_ARG_ISNULL() seems to return true if ANY array element is null; ex::
array[1,2,3,null,4,5]

Comments / improvements welcome.

Kind regards,

John