lua 在c/c++里的调用

lua 与c/c++的变量交换，调用方法

/*
 * main.cpp
 *
 * Created on: 2013-1-9
 * Author: root
 */
#include <lua.hpp>
#include <iostream>

using namespace std;

    void InitLua(lua_State *L)
    {
        luaL_openlibs(L);
        if(luaL_dofile(L,"test.lua"))
        {
            cout << "can't load test.lua" << endl;
        }
    }

    //get global statues value from lua
    template<class T>
    class GetLuaData
    {
    public:
        GetLuaData(){}
        ~GetLuaData(){}

        inline T PopLuaNumber(lua_State* pL, const char* name)
            {
                lua_settop(pL,0);
                lua_getglobal(pL,name);
                //check variable is the correct type
                if(!lua_isnumber(pL,1))
                {
                    cout << "n[C++]:Error: Invalid type!";
                }
                T val = (T)lua_tonumber(pL,1);
                lua_pop(pL,1);
                return val;
            }

        inline string PopLuaTableString(lua_State* pL, const char* tableName,const char* var)
        {
            lua_settop(pL,0);
            lua_getglobal(pL,tableName);//把表放堆栈上
            if(!lua_istable(pL,1))
            {
                cout << "n[c++]:Error, " << tableName << " is not a valid table" << endl;
            }

            lua_pushstring(pL,var);//把键放堆栈上
            if(!lua_isstring(pL,-1))
            {
                cout << "n[c++]:Error invalid type!" << endl;
            }
            lua_gettable(pL,-2);// 出棧键值，把键对应表里的数据放在堆栈里键刚才所在的位置
            string sname;
            if(lua_isstring(pL,-1))
            {
                sname = lua_tostring(pL,-1);
            }
            lua_pop(pL,1);
            return sname;
//            else if(lua_isnumber(pL,-1))
//            {
//                T name = (T)lua_tonumber(pL,-1);
//                return name;
//            }
        }

    };


int main(int argc,char* argv[])
{
//    lua_State *L = lua.open();
    lua_State *L = luaL_newstate();
//    luaL_openlibs(L);
//    luaL_dofile(L, "test.lua");
    InitLua(L);

//    lua_settop(L,0);
//    lua_getglobal(L,"user_score");
//    lua_getglobal(L,"comp_score");
//    if(!lua_isnumber(L,1) || !lua_isstring(L,2))
//    {
//        cout << "n[C++]: Error: Invalid type!";
//    }

//    string a = lua_tostring(L,1);
//    string b = lua_tostring(L,2);
//    int a = (int)lua_tonumber(L,1);
//    int b = (int)lua_tonumber(L,2);
    GetLuaData<int> tmpLua;
    int a = tmpLua.PopLuaNumber(L,"user_score");
    int b = tmpLua.PopLuaNumber(L,"comp_score");
    cout << " a = " << a << " b = " << b << endl;

    string c = tmpLua.PopLuaTableString(L,"simple_table","name");
    cout << " name = " << c << endl;

//lua function，C，C＋＋中调用lua的函数
    lua_getglobal(L,"add");
    if(!lua_isfunction(L,-1))
    {
        cout << "nn[c++]:Ops! The lua function 'add' has not been defined";
    }
    else
    {
        lua_pushnumber(L,5);
        lua_pushnumber(L,8);
        lua_call(L,2,1);
        int result = (int)lua_tonumber(L,-1);
        lua_pop(L,1);
        cout << "result = " << result << endl;
    }


    lua_close(L);

    return 0;
}
//=========================C，C＋＋函数暴露给lua，调用==============================
//C函数，不能直接被调用，需要使用一个包装函数以满足调用方式
void EvaluateTheGuess(string user_guess,string comp_guess,int &user_score,int &comp_score)
{

}
int cpp_EvaluateTheGuesses(lua_State* pL)
{
    int n = lua_gettop(pL);
    if( n != 4 )
    {
        std::cout << "n[c++]: Wrong number of arguments for cpp_EvaluateTheGuesses";
    }

    if(!lua_isstring(pL,1) || !lua_isstring(pL,2) ||
            !lua_isnumber(pL,3) || !lua_isnumber(pL,4))
    {
        std::cout << "n[c++]: Error: Invalid types passed to cpp_evaluateTheGuesses";
    }

    std::string user_guess = lua_tostring(pL,1);
    std::string comp_guess = lua_tostring(pL,1);
    int                        user_score    =(int)lua_tonumber(pL,3);
    int                        comp_score = (int)lua_tonumber(pL,4);

    EvaluateTheGuess(user_guess,comp_guess,user_score,comp_score);

    lua_pushnumber(pL,user_score);
    lua_pushnumber(pL,comp_score);

    return 2;
}
// lua中注册后可以调用cpp_EvaluateTheGuesses函数
int regFunction(lua_State* pL)
{
    lua_register(pL,"cpp_EvaluateTheGuesses",cpp_EvaluateTheGuesses);
    return 1;
}

lua 测试脚本

simple_table = {name="Dan dare", age=20}
function add(a,b)
  return (a+b)
end
math.randomseed(os.time())
user_score = 0
comp_score = 0
lookup = {};
lookup["rock"] = {rock = "draw",paper = "lose", scissors = "win" }
lookup["paper"] = {rock= "win", paper = "draw", scissors = "lose"}
lookup["scissors"] = {rock = "lose", paper = "win", scissors = "draw"}

function GetAIMove()
    local int_to_name = {"scissors","rock","paper"}
    return int_to_name[math.random(3)]
end

function EvaluateTheGuesses(user_guess,comp_guess)
    print("user guess... "..user_guess.." comp guess... "..comp_guess)
    if (lookup[user_guess][comp_guess] == "win") then
        print("You Win the Round!")
        user_score = user_score + 1
        elseif (lookup[user_guess][comp_guess]) == "lose" then
                print("Computer wins the Round")
                comp_score = comp_score + 1
        else
                print("Draw!")
                print(lookup[user_guess][comp_guess])
        end
    end

    --[[主游戏循环]]
    print("enter q to quit game");
    print()
    loop = true
    while loop == true do
        print("User: "..user_score.." computer: "..comp_score)
        user_guess = io.stdin:read '*l'
        local letter_to_string = {s = "scissors", r = "rock", p = "paper"}
        if user_guess == "q" then
            loop = false
        elseif    (user_guess == "r") or (user_guess == "p") or (user_guess == "s") then
            comp_guess = GetAIMove()
            EvaluateTheGuesses(letter_to_string[user_guess],comp_guess)
        else
            print("Invalid input, try again")
        end
    end