Typecasting within sql statement.

Hi there,
    I have a need to create a field value from a function.  The
problem I have is that the field and the return of the function are of
different types. Any ideas how one would do the following?

update table set varchar=func(int4);

I have tried update table set varchar=varchar(func(int4));

but I get an error "function varchar(int4) does not exist"

There must be a way to do it without writing the varchar function.  Can
anyone help me out?  Thanks.

--
Colin Dick
On Call Internet Services
cdick@mail.ocis.net