[Oracle] ORA-02287: sequence number not allowed here

Problem
Assume I create a sequence as bellows:

create sequence seq_test
    start with 1
    increment by 1;

As I try to get the next sequence value in my select statement, I get ORA-02287 error

 select (select lpad(to_char(seq_test.NEXTVAL), 4, '0') from dual) as seq,
        .........
 from ............
 where .........

How-To
1. create a function to get the next sequence

    FUNCTION FN_GET_NEXT_SEQ_VAL RETURN VARCHAR2 IS v_next_seq_val VARCHAR2(4) := '';
    BEGIN
        select lpad(to_char(seq_test.NEXTVAL), 4, '0')
        into v_next_seq_val
        from dual;

        return v_next_seq_val;
    END FN_GET_NEXT_SEQ_VAL;

2. select value from function

    select FN_GET_NEXT_SEQ_VAL() as seq,
           .........
    from ............
    where .........

Reference
Uses and Restrictions of NEXTVAL and CURRVAL

CURRVAL and NEXTVAL can be used in the following places:

• VALUES clause of INSERT statements
• The SELECT list of a SELECT statement
• The SET clause of an UPDATE statement

CURRVAL and NEXTVAL cannot be used in these places:

• A subquery
• A view query or materialized view query
• A SELECT statement with the DISTINCT operator
• A SELECT statement with a GROUP BY or ORDER BY clause
• A SELECT statement that is combined with another SELECT statement with the UNION, INTERSECT, or MINUS set operator
• The WHERE clause of a SELECT statement
• DEFAULT value of a column in a CREATE TABLE or ALTER TABLE statement
• The condition of a CHECK constraint