meta: newproxy can accept a userdata value

[Bilal2453]

In the Lua 5.1 source code (Lua 5.1.5 lbaselib.c#432-440):

  else {
    int validproxy = 0;  /* to check if weaktable[metatable(u)] == true */
    if (lua_getmetatable(L, 1)) {
      lua_rawget(L, lua_upvalueindex(1));
      validproxy = lua_toboolean(L, -1);
      lua_pop(L, 1);  /* remove value */
    }
    luaL_argcheck(L, validproxy, 1, "boolean or proxy expected");
    lua_getmetatable(L, 1);  /* metatable is valid; get it */
  }

So newproxy can accept a userdata created previously with newproxy(true):

[sumneko]

Thank you!