Function can_be_hatched

src/mon.c:5545–5565

* Determine if the given monster number can be hatched from an egg. * Return the monster number to use as the egg's corpsenm. Return * NON_PM if the given monster can't be hatched. */

 * NON_PM if the given monster can't be hatched.
 */
int
can_be_hatched(int mnum)
{
    /* ranger quest nemesis has the oviparous bit set, making it
       be possible to wish for eggs of that unique monster; turn
       such into ordinary eggs rather than forbidding them outright */
    if (mnum == PM_SCORPIUS)
        mnum = PM_SCORPION;

    mnum = little_to_big(mnum);
    /*
     * Queen bees lay killer bee eggs (usually), but killer bees don't
     * grow into queen bees.  Ditto for [winged-]gargoyles.
     */
    if (mnum == PM_KILLER_BEE || mnum == PM_GARGOYLE
        || (lays_eggs(&mons[mnum])
            && (BREEDER_EGG
                || (mnum != PM_QUEEN_BEE && mnum != PM_WINGED_GARGOYLE))))
        return mnum;
    return NON_PM;
}

/* type of egg laid by #sit; usually matches parent */
int