tt_
#define TValuefields Value value_; int tt_
#define rttype(o) ((o)->tt_)
#define settt_(o,t) ((o)->tt_=(t))
io1->value_ = io2->value_; io1->tt_ = io2->tt_; \
#define ttisnumber(o) ((tt_(o) & NNMASK) != NNMARK)
#define rttype(o) (ttisnumber(o) ? LUA_TNUMBER : tt_(o) & 0xff)
#define settt_(o,t) (tt_(o) = tag2tt(t))
#define checktag(o,t) (tt_(o) == tag2tt(t))
#define checktype(o,t) (ctb(tt_(o) | VARBITS) == ctb(tag2tt(t) | VARBITS))
(ttisnumber(o1) ? ttisnumber(o2) : (tt_(o1) == tt_(o2)))