if (mons_res_cold( &menv[mnstr] ) > 0 && coinflip())        return 0;
    if (menv[mnstr].has_ench(ENCH_SLEEP_WARY))         return 0;

    if (mons_res_cold( &menv[mnstr] ) > 0 && coinflip())
        return 0;
    if (menv[mnstr].has_ench(ENCH_SLEEP_WARY))
        return 0;

    menv[mnstr].behaviour = BEH_SLEEP;
    menv[mnstr].add_ench(ENCH_SLEEPY);
    menv[mnstr].add_ench(ENCH_SLEEP_WARY);

    menv[mnstr].put_to_sleep();

void monsters::put_to_sleep(int)
{
    behaviour = BEH_SLEEP;
    add_ench(
        mon_enchant(ENCH_SLEEPY, 0, KC_OTHER,
                    12 * speed_to_duration(speed)));
    add_ench(ENCH_SLEEP_WARY);
}

    virtual void put_to_sleep(int power = 0) { };

    void put_to_sleep(int power = 0);

        mon->behaviour = BEH_SLEEP;
        mon->add_ench(ENCH_SLEEPY);
        mon->add_ench(ENCH_SLEEP_WARY);

        mon->put_to_sleep();