Using user defined function inside package

Hi,

I am trying to get the following PL/SQL statement to work in a package, but have not had any success.

I have created a function called ISDATE - The ddl is below:

create or replace function isdate
( p_string in varchar2,
p_fmt in varchar2 := null)
return boolean
as
l_date date;
begin
l_date :=
to_date(p_string,p_fmt);
return TRUE;
exception
when others then
return FALSE;
end;


I perform the following select statement:

SELECT TRANSACTIONPROCESSDT INTO VTRANPRODTCHAR FROM TABLE1
WHERE .....

VTRANPRODCHAR is defined as a BOOLEAN;

I perform my test
IF ISDATE(VTRANPRODTCHAR,'DD-Mon-YYYY') = 'FALSE'
THEN

INSERT INTO TEMP_ERR_CHK ( CLAIMNO , RESERVENO, TRANSACTIONPROCESSDT,ERROR_MESSAGE_CD,REPORTING_DATE,LOAD_PROCESS_DATE_TIME )
VALUES(VCLAIMNO , VRESERVENO , VTIME_DATE,310,VREPORTING_DATE,CURRENT_TIMESTAMP);

END IF;


But I get the following error
PLS-00306: wrong number or types of arguments in call to 'ISDATE'

Why is this returning an error - who do i fix it?

thanks

you have defined your function to accept to in parameters of type varchar2, but then you pass a boolean variable 'VTRANPRODTCHAR' into it as the first parameter.

I think you need to call it something like

date_str VARCHAR2 := '01-Jan-2007';

IF NOT ISDATE(date_str,'DD-Mon-YYYY')
THEN

.....