Function cannot_use_schools

crawl-ref/source/spl-util.cc:1919–1938

* Are some subset of the given schools unusable by the player? * (Due to Sacrifice Arcana) * * @param schools A bitfield containing a union of spschools. * @return Whether the player is unable use any of the given schools. */

 * @return          Whether the player is unable use any of the given schools.
 */
bool cannot_use_schools(spschools_type schools)
{
    COMPILE_CHECK(ARRAYSZ(arcana_sacrifice_map) == SPSCHOOL_LAST_EXPONENT + 1);

    // iter over every school
    for (int i = 0; i <= SPSCHOOL_LAST_EXPONENT; i++)
    {
        // skip schools not in the provided set
        const auto school = spschools_type::exponent(i);
        if (!(schools & school))
            continue;

        // check if the player has this school locked out
        const mutation_type lockout_mut = arcana_sacrifice_map[i];
        if (you.has_mutation(lockout_mut))
            return true;
    }

    return false;
}


/**