public void write(Operation op) {   Operation old = m_op; try { m_op = op; op.write(this); } finally { m_op = old; }
public void write(String str) { m_sql.append(str);
    public void write(Operation op) {        // XXX: this is a hack, for binding to work properly we need to call        // the Operation version of write.        Operation old = m_op;        try {            m_op = op;            op.write(this);        } finally {            m_op = old;        }    }