Procedure calling syntax with complex types

Say I have a type defined as

city (varchar, varchar(2), numeric, numeric)

What would be the syntax for calling a stored procedure defined with this
type as a parameter, i.e., something like

 CREATE FUNCTION public.city_insert(city)
  RETURNS ...

That is, I want to do something like

SELECT public.city_insert(CAST('Waterford', 'CT', 41.346853,-72.14582) AS
city);

but I don't think this syntax works.

--Berend Tober