potion_str_slice_index  253 core/string.c                           PN_INT(potion_str_slice_index(start, len, 0)));
potion_str_slice_index  261 core/string.c                    PN_INT(potion_str_slice_index(start+end, len, len)));
potion_str_slice_index  264 core/string.c                    PN_INT(potion_str_slice_index(end, len, len)));
potion_str_slice_index  303 core/string.c      start = PN_INT(potion_str_slice_index(index, len, 0)); // supports s(-1)