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widget.h

string vector gadget.h

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widget.cpp

string vector gadget.h widget.h

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조금더나은모양

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header에서는 정의만할수있도록할것.

???

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Effective Modern C++ StudyC++ Korea

template<typename T>void func(T&& param);

T가 아닌 param의 type

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template<typename T>void func(T&& param);

Widget widgetFactory(); // function returning rvalueWidget w; // a variable (an lvalue)func(w); // call func with lvalue; T deduced

// to be Widget&func(widgetFactory()); // call func with rvalue; T deduced

// to be Widget

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int x;auto& & rx = x; // error! can't declare reference to reference

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void func(Widget& && param);

void func(Widget& param);

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template<typename T>void f(T&& fParam){

someFunc(std::forward<T>(fParam)); // forward fParam to} // someFunc

template<typename T> T&& forward(typename remove_reference<T>::type& param){

return static_cast<T&&>(param);}

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Widget& && forward(typenameremove_reference<Widget&>::type& param){

return static_cast<Widget& &&>(param);}

Widget& && forward(Widget& param){

return static_cast<Widget& &&>(param);}

Widget& forward(Widget& param) {

return static_cast<Widget&>(param);}

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Widget&& forward(typenameremove_reference<Widget>::type& param){

return static_cast<Widget&&>(param);}

Widget&& forward(Widget& param){

return static_cast<Widget&&>(param);}

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template<typename T> T&& forward(remove_reference_t<T>& param) {

return static_cast<T&&>(param);}

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template<typename T>void func(T&& param);Widget widgetFactory(); // function returning rvalueWidget w; // a variable (an lvalue)func(w); // call func with lvalue; T deduced

// to be Widget&func(widgetFactory()); // call func with rvalue; T deduced

// to be Widget

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auto&& w1 = w;

Widget& && w1 = w;

auto&& w2 = widgetFactory();

Widget&& w2 = widgetFactory();

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template<typename T>class Widget {public:typedef T&& RvalueRefToT;

};

Widget<int&> w;

typedef int& && RvalueRefToT;

typedef int& RvalueRefToT;

Effective Modern C++ StudyC++ Korea

Effective Modern C++ StudyC++ Korea