eris: refactoring table API so that table methods can see value being inserted

luprex/eris-master/src/lvm.c

@@ -139,19 +139,13 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
     const TValue *tm;
     if (ttistable(t)) {  /* `t' is a table? */
       Table *h = hvalue(t);
-      TValue *oldval = cast(TValue *, luaH_get(h, key));
+      const TValue *oldval = luaH_get(h, key);
       /* if previous value is not nil, there must be a previous entry
          in the table; moreover, a metamethod has no relevance */
       if (!ttisnil(oldval) ||
          /* previous value is nil; must check the metamethod */
-         ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL &&
-         /* no metamethod; is there a previous entry in the table? */
-         (oldval != luaO_nilobject ||
-         /* no previous entry; must create one. (The next test is
-            always true; we only need the assignment.) */
-         (oldval = luaH_newkey(L, h, key), 1)))) {
-        /* no metamethod and (now) there is an entry with given key */
-        setobj2t(L, oldval, val);  /* assign new value to that entry */
+         ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL)) {
+        luaH_setupdate(L, h, key, val, oldval);
         invalidateTMcache(h);
         luaC_barrierback(L, obj2gco(h), val);
         return;