Function luaV_settable

lua/lvm.c:135–171

void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
  int loop;
  for (loop = 0; loop < MAXTAGLOOP; loop++) {
    const TValue *tm;
    if (ttistable(t)) {  /* `t' is a table? */
      Table *h = hvalue(t);
      TValue *oldval, *foundkey = NULL;
      oldval = luaH_set_int(L, h, key, &foundkey); /* do a primitive set */
      if (!ttisnil(oldval) ||  /* result is no nil? */
          (tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
        if (foundkey) {
          if (ttype(foundkey) != ttype(key)) {
            setobj2t(L, foundkey, key);
          } else if (ttype(foundkey) == LUA_TUSERDATA) {
            int f = luabb_dbtype_from_tvalue(foundkey);
            int k = luabb_dbtype_from_tvalue(key);
            if (f != k) {
              setobj2t(L, foundkey, key);
            }
          }
        }
        setobj2t(L, oldval, val);
        luaC_barriert(L, h, val);
        return;
      }
      /* else will try the tag method */
    }
    else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
      luaG_typeerror(L, t, "index");
    if (ttisfunction(tm)) {
      callTM(L, tm, t, key, val);
      return;
    }
    t = tm;  /* else repeat with `tm' */
  }
  luaG_runerror(L, "loop in settable");
}


static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2,