setnvalue
setnvalue(o1, luaO_arith(op, nvalue(o1), nvalue(o2)));
setnvalue(L->top, n);
setnvalue(L->top, cast_num(n));
setnvalue(L->top, n);
setnvalue(idx, cast_num(k));
setnvalue(&o, r);
setnvalue(L->top++, cast_num(va_arg(argp, int)));
setnvalue(L->top++, cast_num(va_arg(argp, l_uacNumber)));
setnvalue(key, cast_num(i+1));
setnvalue(&k, cast_num(key));
setnvalue(o,LoadNumber(S));
setnvalue(ra, cast_num(luaH_getn(h))); /* else primitive len */
setnvalue(ra, cast_num(tsvalue(rb)->len));
setnvalue(n, num);
setnvalue(ra, res);
setnvalue(ra, op(L, nb, nc)); \
setnvalue(ra, luai_numunm(L, nb));
setnvalue(ra, idx); /* update internal index... */
setnvalue(ra+3, idx); /* ...and external index */
setnvalue(ra, luai_numsub(L, nvalue(ra), nvalue(pstep)));