Trigger and function not on speaking terms

Hmm, this is puzzling me:

create or replace function fn_foo(text) returns trigger as '
begin  # Do some stuff with $1
end;
' language 'plpgsql';

CREATE FUNCTION

create table bar (aaa text);

CREATE TABLE

create trigger trg_bar
after insert or update on bar
execute procedure fn_foo('string');

ERROR:  function fn_foo() does not exist

It would seem my trigger definition is trying to find fn_foo(), when I 
mean for it to call fn_foo(TEXT).

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Jeffery Boes <>< jboes@qtm.net