Encapsulates the work that will be done for case 6 of __embed_frond,
    since it gets used in more than one place.

def __do_case_6_work(d_w, d_u, case_1, case_2, case_3, dfs_data):
    """Encapsulates the work that will be done for case 6 of __embed_frond,
    since it gets used in more than one place."""
    # --We should only ever see u-cases 1 and 3
    if case_2:
        # --We should never get here
        return False

    comp_d_w = abs(d_w)

    # --Add the frond to the right side
    __insert_frond_RF(d_w, d_u, dfs_data)

    # --Add uw to Rm
    m = dfs_data['FG']['m']
    Rm = R(m, dfs_data)
    if comp_d_w < Rm['x']:
        Rm['x'] = d_w
    if d_u > Rm['y']:
        Rm['y'] = d_u

    # --Case 3 requires a bit of extra work
    if case_3:
        Rm['x'] = d_w
        u_m1 = u(m-1, dfs_data)
        while comp_d_w < u_m1:
            merge_Fm(dfs_data)
            m = dfs_data['FG']['m']
            u_m1 = u(m-1, dfs_data)
    #else:
        #print "Case 6 work, u-case 1"

    return True