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@nonedark2008
908 / 647 / 134
Регистрация: 28.07.2012
Сообщений: 1,760
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01.07.2016, 18:55
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rikimaru2013, ну тогда что-то такое:
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| #include <iostream>
#include <functional>
#include <type_traits>
using namespace std;
//////////////////////////////////////////////////////////////////////////
class IFoo
{
public:
virtual void onAppStarted(int, int) = 0;
};
//////////////////////////////////////////////////////////////////////////
template <typename T>
struct FunctionTypeDeduction : public FunctionTypeDeduction<decltype(&T::operator())>
{};
//////////////////////////////////////////////////////////////////////////
template<class ClassType, class ReturnType, class... Args>
struct FunctionTypeDeduction< ReturnType(ClassType::*)(Args...) >
{
using type = ReturnType(*)(Args...);
using functorType = std::function<ReturnType(Args...) >;
};
//////////////////////////////////////////////////////////////////////////
template<class ClassType, class ReturnType, class... Args>
struct FunctionTypeDeduction< ReturnType(ClassType::*)(Args...) const> : FunctionTypeDeduction< ReturnType(ClassType::*)(Args...)>
{};
//////////////////////////////////////////////////////////////////////////
class SubcribeSystem
{
public:
using tSomeMethodType = FunctionTypeDeduction< decltype(&IFoo::onAppStarted) >::type;
using tSomeMethodCallback = FunctionTypeDeduction< decltype(&IFoo::onAppStarted) >::functorType;
public:
void subribeOnSomeMethod(const tSomeMethodCallback& arr)
{
arr(3, 19);
}
};
#define SUBCRIBE_FOR_SOMEMETHOD( eventsObj, lambda ) \
do \
{ \
static_assert(is_same<SubcribeSystem::tSomeMethodType, FunctionTypeDeduction<decltype(lambda)>::type>::value, "bad type"); \
SubcribeSystem::tSomeMethodCallback const func_ptr = lambda; \
eventsObj.subribeOnSomeMethod( lambda ); \
} \
while(false);
//////////////////////////////////////////////////////////////////////////
class Bar
{
public:
void fn(SubcribeSystem& events)
{
auto onAppStart = [](int width, int height)
{
cout << width << " " << height << endl;
};
auto onAppStart2 = [](bool width, int height)
{
cout << width << " " << height << endl;
};
auto onAppStart3 = [this](int width, int height)
{
cout << width << " " << height << endl;
someOtherMethod(width);
};
SUBCRIBE_FOR_SOMEMETHOD(events, onAppStart); // expect ok
SUBCRIBE_FOR_SOMEMETHOD(events, onAppStart2); // expect error
SUBCRIBE_FOR_SOMEMETHOD(events, onAppStart3); // expect ok
}
void someOtherMethod(int x)
{
cout << "processed callback " << x << endl;
}
};
int main()
{
Bar bar;
SubcribeSystem sub;
bar.fn(sub);
} |
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Как дедуцировать тип лямбды я честно нарыл в интернете...
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