PL/pgSQL manual

Sorry for the last post, finger error.

Anyways, I find all types of example like this:

CREATE FUNCTION somefunc() RETURNS INTEGER AS

I'm looking for an example of a function that will prevent an insert
based on a pattern match. Is this possible and if so DO I need to return
something? I guess to sum to it up, I need a function that will match a
pattern and then a trigger that will not allow an insert based on what
that function matches.

I'm sure I am just making this harder than it really is...

 ***PRIVILEGED & CONFIDENTIAL***
Unless expressly stated otherwise, this message (and any attachment(s)
thereto) is confidential and may be privileged. It is intended for the
addressee(s) only. If you are not an addressee, any disclosure or
copying of the contents of this e-mail or any action taken (or not
taken) in reliance on it is strictly prohibited. If you are not an
addressee, please inform sender immediately and delete this message from
your system.