Lua5.2嵌入到C++中。

我第一次尝试在C++中嵌入Lua。我已经搜索了2天，但大多数互联网tutos使用lua5.1，这与lua5.2不兼容。所以我阅读了一些lua文档、示例源代码，最终得到了这个：

main.cpp：

#include "luainc.h"
#include <iostream>

int main(){
    int iErr = 0;
    lua_State *lua = luaL_newstate ();  // Open Lua
    luaopen_io (lua);    // Load io library

    if ((iErr = luaL_loadfile (lua, "hw.lua")) == 0)
    {
       std::cout<<"step1"<<std::endl;

       if ((iErr = lua_pcall (lua, 0, LUA_MULTRET, 0)) == 0)
       {
          std::cout<<"step2"<<std::endl;

          lua_getglobal (lua, "helloWorld");    // Push the function name onto the stack

            if (lua_type(lua, lua_gettop(lua)) == LUA_TNIL) {
                // if the global variable does not exist then we will bail out with an error.
                std::cout<<"global variable not found : helloworld"<<std::endl;

                /* error so we will just clear the Lua virtual stack and then return
if we do not clear the Lua stack, we leave garbage that will cause problems with later
function calls from the application. we do this rather than use lua_error() because this function
is called from the application and not through Lua. */

                lua_settop (lua, 0);
                return -1;
            }

          // Function is located in the Global Table
          /* lua_gettable (lua, LUA_GLOBALSINDEX);  */ //lua5.1
          lua_pcall (lua, 0, 0, 0);
       }
    }

    lua_close (lua);

    return 0;
}

hw.lua：

-- Lua Hello World (hw.lua)
function helloWorld ()
   io.write ("hello World")
end

luainc.h：

#ifndef __LUA_INC_H__
#define __LUA_INC_H__

extern "C"
{
   #include </home/renardc/Documents/Programmation/Lua_CPP/lua-5.2.2/src/lua.h>
   #include </home/renardc/Documents/Programmation/Lua_CPP/lua-5.2.2/src/lauxlib.h>
   #include </home/renardc/Documents/Programmation/Lua_CPP/lua-5.2.2/src/lualib.h>
}

#endif // __LUA_INC_H__

我没有错误，输出是：

step1
step2

这应该意味着我的“helloworld”函数已经被找到。但由于输出中看不到“Hello World”，我怀疑函数没有被调用。我做错了什么？

这是我如何编译我的程序：

g++ main.cpp -L/usr/local/include -I/usr/local/include -llua