Check user_arguments table : user_arguments « System Tables Data Dictionary « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. System Tables Data Dictionary
3. user_arguments

SQL>
SQL> SELECT object_name, argument_name, overload
  2       , POSITION, SEQUENCE, data_level, data_type
  3    FROM user_arguments
  4   WHERE data_type IN ('LONG','CHAR');

OBJECT_NAME                    ARGUMENT_NAME
------------------------------ ------------------------------
OVERLOAD                                   POSITION   SEQUENCE DATA_LEVEL
---------------------------------------- ---------- ---------- ----------
DATA_TYPE
------------------------------
F1
                                                  0          1          0
CHAR


SQL>
SQL>