// Mummies can fall apart in water; ghouls, vampires, and demons can
    // drown in water/lava.
    // Other undead just "sink like a rock", to be never seen again.

    // Mummies can fall apart in water or be incinerated in lava.
    // Ghouls, vampires, and demons can drown in water or lava.  Others
    // just "sink like a rock", to never be seen again.

            || holiness() == MH_DEMONIC);

            || mons_holiness(this) == MH_DEMONIC);

    mon_holy_type holy = mons_holiness(this);
    if (holy == MH_UNDEAD || holy == MH_DEMONIC || holy == MH_NONLIVING)

    const mon_holy_type holy = mons_holiness(this);
    if (holy == MH_UNDEAD
        || holy == MH_DEMONIC
        || holy == MH_NONLIVING)
    {

    }