MirLua: lambda-based metatables wrapper

git-svn-id: http://svn.miranda-ng.org/main/trunk@16096 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 50 insertions, 23 deletions

diff --git a/plugins/MirLua/src/mlua_metatable.h b/plugins/MirLua/src/mlua_metatable.h
index eb8ee722d2..e0c2f1adb3 100644
--- a/plugins/MirLua/src/mlua_metatable.h
+++ b/plugins/MirLua/src/mlua_metatable.h
@@ -1,18 +1,47 @@
 #ifndef _LUA_METATABLE_H_

 #define _LUA_METATABLE_H_

 

+#include <functional>

+

+#define LFUNC(T, L) std::function<void*(T*)>(L)

+

 #define LUA_TINTEGER LUA_NUMTAGS + 1

 #define LUA_TSTRINGA LUA_NUMTAGS + 2

 #define LUA_TSTRINGW LUA_NUMTAGS + 3

 

-struct MTField

+enum MTFieldGetType

+{

+	MTFGT_LAMBDA = 1,

+	MTFGT_OFFSET = 2

+};

+

+template<typename T>

+struct MTField : public MZeroedObject

 {

 	size_t offset;

 	size_t size;

 	int type;

+	int getType;

+	std::function<void*(T*)> lambda;

 

 	MTField(size_t offset, size_t size, int type)

-		: offset(offset), size(size), type(type) { }

+		: offset(offset), size(size), type(type), getType(MTFGT_OFFSET) { }

+

+	MTField(std::function<void*(T*)> f, int type)

+		: lambda(f), type(type), getType(MTFGT_LAMBDA) { }

+

+	template<typename R = void*>

+	R GetValue(T *obj) const

+	{

+		if (getType == MTFGT_LAMBDA) return (R)lambda(obj);

+		else

+		{

+			R res = NULL;

+			memcpy(&res, ((char*)obj) + offset, size);

+			return res;

+		}

+	}

+

 };

 

 template<typename T>

@@ -22,15 +51,7 @@ private:
 	lua_State *L;

 

 	static const char *name;

-	static std::map<std::string, MTField*> fields;

-

-	template<typename R>

-	static R GetValue(const T *obj, size_t offset, size_t size)

-	{

-		R res = NULL;

-		memcpy(&res, ((char*)obj) + offset, size);

-		return res;

-	}

+	static std::map<std::string, MTField<T>*> fields;

 

 	static void Init(lua_State *L, T **obj)

 	{

@@ -71,32 +92,30 @@ private:
 			return 1;

 		}

 

-		MTField *field = it->second;

-		size_t offset = field->offset;

-		size_t size = field->size;

+		MTField<T> *field = it->second;

 		

 		switch (field->type)

 		{

 		case LUA_TBOOLEAN:

-			lua_pushboolean(L, GetValue<bool>(obj, offset, size));

+			lua_pushboolean(L, field->GetValue<BOOL>(obj));

 			break;

 		case LUA_TINTEGER:

-			lua_pushinteger(L, GetValue<long long>(obj, offset, size));

+			lua_pushinteger(L, field->GetValue<long>(obj));

 			break;

 		case LUA_TNUMBER:

-			lua_pushnumber(L, GetValue<double>(obj, offset, size));

+			lua_pushnumber(L, field->GetValue<intptr_t>(obj));

 			break;

 		case LUA_TSTRING:

-			lua_pushstring(L, GetValue<char*>(obj, offset, size));

+			lua_pushstring(L, field->GetValue<char*>(obj));

 			break;

 		case LUA_TSTRINGA:

-			lua_pushstring(L, ptrA(mir_utf8encode(GetValue<char*>(obj, offset, size))));

+			lua_pushstring(L, ptrA(mir_utf8encode(field->GetValue<char*>(obj))));

 			break;

 		case LUA_TSTRINGW:

-			lua_pushstring(L, ptrA(mir_utf8encodeW(GetValue<wchar_t*>(obj, offset, size))));

+			lua_pushstring(L, ptrA(mir_utf8encodeW(field->GetValue<wchar_t*>(obj))));

 			break;

 		case LUA_TLIGHTUSERDATA:

-			lua_pushlightuserdata(L, GetValue<void*>(obj, offset, size));

+			lua_pushlightuserdata(L, field->GetValue(obj));

 			break;

 		default:

 			lua_pushnil(L);

@@ -134,7 +153,15 @@ public:
 	{

 		size_t offset = reinterpret_cast<size_t>(&(((T*)0)->*M));

 		if (type != LUA_TNONE)

-			fields[name] = new MTField(offset, size, type);

+			fields[name] = new MTField<T>(offset, size, type);

+		return *this;

+	}

+

+	template<typename R>

+	MT& Field(std::function<R(T*)> f, const char *name, int type)

+	{

+		if (type != LUA_TNONE)

+			fields[name] = new MTField<T>(f, type);

 		return *this;

 	}

 

@@ -165,6 +192,6 @@ template<typename T>
 const char *MT<T>::name;

 

 template<typename T>

-std::map<std::string, MTField*> MT<T>::fields;

+std::map<std::string, MTField<T>*> MT<T>::fields;

 

 #endif //_LUA_METATABLE_H_