亚洲香蕉网久久综合影视 ,久久99精品国产麻豆宅宅,色婷婷久久久SWAG精品

用preload加載Lua導出模塊

用preload加載Lua導出模塊

(金慶的專欄 2017.5)

參考：
How to make exported module non-global?
https://github.com/SteveKChiu/lua-intf/issues/135

動態庫可以這樣導出模塊：

    extern "C"
    #if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CODEGEARC__)
    __declspec(dllexport)
    #endif
    int luaopen_modname(lua_State* L)
    {
        LuaRef mod = LuaRef::createTable(L);
        LuaBinding(mod)
            ...;
        mod.pushToStack();
        return 1;
    }

如果不是動態庫，可以這樣導出全局模塊 c_util：

int main()
{
   ...
   LuaBinding(L).beginModule("c_util")
       .addFunction("foo", []() { return 123; })
   .endModule();
   ...
}

如果不想讓它成為全局模塊，則需要在 package.preload 表中注冊一個加載函數.

Lua程序設計第3版英文版 programming in lua 3ed

The preload searcher allows the definition of an arbitrary function to load a module.
It uses a table, called package.preload, to map module names to loader functions.
When searching for a module name, this searcher simply looks for the given name in the table.
If it finds a function there, it returns this function as the module loader.
Otherwise, it returns nil.
This searcher provides a generic method to handle some non-conventional situations.
For instance, a C library statically linked to Lua can register its luaopen_ function into the preload table,
so that it will be called only when (and if) the user requires that module.
In this way, the program does not waste time opening the module if it is not used.

代碼示例：

    extern "C" int open_my_module(lua_State* L)
    {
        LuaRef mod = LuaRef::createTable(L);
        LuaBinding(mod)
            .addFunction("get_my_svr_id", &Util::GetMySvrId)
            ;
        mod.pushToStack();
        return 1;
    }

   int main()
   {
       ...
       LuaRef table(L, "package.preload");
       table["c_util"] = LuaRef::createFunctionWith(L, open_my_module);
       ...
   }

Lua 測試：
   assert(c_util == nil)
   local t = require("c_util")
   assert("table" == type(t))
   assert("function" == type(t.get_my_svr_id))

posted on 2017-05-10 16:11 金慶閱讀(746) 評論(0) 編輯收藏引用所屬分類: 1. C/C++

只有注冊用戶登錄后才能發表評論。
【推薦】100%開源！大型工業跨平臺軟件C++源碼提供，建模，組態！

相關文章: How are dtLinks created in NavMesh C++ parameter passing rules Naming Conventions for Accessors Visual Studio 2019 Compiler Hangs Fbx File Format Identifier 查找內存錯誤 std::thread 中的異常會丟失調用棧用賦值代替 protobuf CopyFrom() vs2017 linux 編譯輸出改成 vs 格式為 LiteIDE 添加選中標記

網站導航: 博客園 IT新聞 BlogJava 博問 Chat2DB 管理

金慶的專欄

公告

留言簿(12)

隨筆分類(502)

隨筆檔案(423)

相冊

搜索

積分與排名

最新評論

閱讀排行榜

評論排行榜