Select from function with named parameters doesn't work

Question

Hello,
I'm trying to execute the next sql statement:
SELECT mypack.getvalue(user_id => 231, status => 'closed') AS someAlias FROM DUAL;
I'm getting the next Error:
Error: ORA-00907: missing right parenthesis
But the next works fine:
SELECT mypack.getvalue(231,'closed') AS someAlias FROM DUAL;
What I'm doing wrong?
Is there a way to call a Function and return it's result as a single-row query?
Thanks for any suggestions.

Answer 1

Thanks for your answers.
Just want to explain what I want to accomplish:
I want to create PL/SQL statement which:
1) Calls Function in named notation way;
2) Returns a query which contains a single row - a Function result.
I know in Transact-SQL I can accomplish this the next way:
DECLARE @return_value INT
EXEC[myproc]
@id=2,
@status='ok',
@ret_param=@return_value OUTPUT
SELECT @return_value AS my_return_value
The last SELECT call returns a query with one row in it.
How can I do the same in Oracle?
Thanks a lot!