NOTHING
dungeon[i][j] = NOTHING;
(dungeon[*row][*col] == NOTHING)) ||
(dungeon[row][col] == NOTHING)) && (tries < 15));
(dungeon[*row][*col] == NOTHING)) {
(dungeon[orow][ocol] == NOTHING) ||
(dungeon[row][col] == NOTHING) ||
(dungeon[nrow][ncol] != NOTHING) &&
assert(EQ(step(m->g, startst, stopst, st, NOTHING, st, sflags),
st = step(m->g, startst, stopst, st, NOTHING, st, sflags);
case NOTHING:
(void) regnode(NOTHING);
regtail(ret, regnode(NOTHING)); /* null. */
regtail(ret, regnode(NOTHING)); /* null. */
next = regnode(NOTHING); /* null. */
case NOTHING: