Error trapping in pg/PGSQL

What plans are there for adding error trapping support to pl/PGSQL? In
my case I'm trying to write code that will properly handle the race
condition in doing a SELECT/INSERT (SELECT something but if it doesn't
exist do an INSERT), and I can't see any way to make it fool-proof
without being able to trap a duplicate key error. But it seems like
error trapping is something that would be extremely useful to have aside
from what I'm doing.
--
Jim C. Nasby, Database Consultant                  jim@nasby.net
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