Unnamed

   lua_newtable(L);
   /* table */
   lua_pushnil(L);
   /* table, nil */
   while (lua_next(L, LUA_GLOBALSINDEX) != 0) {
      /* table, key, value */  
      switch (lua_type(L, -1)) {
         case LUA_TNUMBER:
         case LUA_TBOOLEAN:
         case LUA_TSTRING:
            lua_pushvalue(L, -2); /* copy key */
            /* table, key, value, key */
            lua_insert(L, -3); /* key << 3 */
            /* table, key, key, value */
            lua_settable(L, -4); /* table[key] = value */
            /* table, key */
            break;
         
         default:
            lua_pop(L,1);
            /* table, key */
            continue;
      }
   }
   /* table */