161   if (ttisnil(key)) return 0;  /* first iteration */  in findindex()
189     if (!ttisnil(&t->array[i])) {  /* a non-nil value? */  in luaH_next()
196     if (!ttisnil(gval(gnode(t, i)))) {  /* a non-nil value? */  in luaH_next()
275       if (!ttisnil(&t->array[i-1]))  in numusearray()
291     if (!ttisnil(gval(n))) {  in numusehash()
367       if (!ttisnil(&t->array[i]))  in luaH_resize()
376     if (!ttisnil(gval(old))) {  in luaH_resize()
445       if (ttisnil(gkey(t->lastfree)))  in getfreepos()
464   if (ttisnil(key)) luaG_runerror(L, "table index is nil");  in luaH_newkey()
475   if (!ttisnil(gval(mp)) || isdummy(t)) {  /* main position is taken? */  in luaH_newkey()
508   lua_assert(ttisnil(gval(mp)));  in luaH_newkey()
636   while (!ttisnil(luaH_getint(t, j))) {  in unbound_search()
641       while (!ttisnil(luaH_getint(t, i))) i++;  in unbound_search()
649     if (ttisnil(luaH_getint(t, m))) j = m;  in unbound_search()
662   if (j > 0 && ttisnil(&t->array[j - 1])) {  in luaH_getn()
667       if (ttisnil(&t->array[m - 1])) j = m;  in luaH_getn()