variadic-templates

问题 I have tried to write a lambda that measures the execution time of arbitrary functions. With a lot of help I have managed that for C++14 and functions having a return value, see Measure execution time of arbitrary functions with C++14 lambda. Then I wanted my code to also work with C++11, therefore I have implemented the same idea with template functions. Finally I have realized that this code does not work for functions having no return value. It has been quite simple to generalize the

问题 I'd like to avoid the duplicates in the code below. #include <iostream> struct Bar{}; template <class... Args> struct FooClass; template <class... Args> inline void foo(Args&&... args) { FooClass<Args...>::impl(std::forward<Args>(args)...); } // Duplicate 1. // Const ref version template <> struct FooClass<Bar const&> { inline static void impl(const Bar& b) { std::cout << "dup1" << std::endl; } }; // Duplicate 2. // Copy version template <> struct FooClass<Bar> { inline static void impl(const

问题 I'd like to avoid the duplicates in the code below. #include <iostream> struct Bar{}; template <class... Args> struct FooClass; template <class... Args> inline void foo(Args&&... args) { FooClass<Args...>::impl(std::forward<Args>(args)...); } // Duplicate 1. // Const ref version template <> struct FooClass<Bar const&> { inline static void impl(const Bar& b) { std::cout << "dup1" << std::endl; } }; // Duplicate 2. // Copy version template <> struct FooClass<Bar> { inline static void impl(const

问题 Having the code snippet below (under C++17 standard): template <class ...TParams> class Wrapper { public: template <template <class, TParams...> class TTemplate, class TValue, TParams ...params> class Base { public: TTemplate<TValue, params...> value; }; }; template <class T, bool Param1, int Param2> class Class { public: T value; bool boolean = Param1; int integer = Param2; }; template <class T, bool Param1, int Param2> class Derived :public Wrapper<bool, int>::Base<Class, T, Param1, Param2>

问题 Having the code snippet below (under C++17 standard): template <class ...TParams> class Wrapper { public: template <template <class, TParams...> class TTemplate, class TValue, TParams ...params> class Base { public: TTemplate<TValue, params...> value; }; }; template <class T, bool Param1, int Param2> class Class { public: T value; bool boolean = Param1; int integer = Param2; }; template <class T, bool Param1, int Param2> class Derived :public Wrapper<bool, int>::Base<Class, T, Param1, Param2>

问题 I have seen a CRTP solution, which extracted the interface into the base class, and friended only one of the pack arguments per base class. Then the most derived class inherited all the friended base classes and implemented the interface. I cannot use this approach, since I need to protect the assignment operator, which is not inherited. Also, since the assignment operator has a defined signature with exactly one parameter, I cannot use a key pattern. This is what I would like to have:

问题 I have seen a CRTP solution, which extracted the interface into the base class, and friended only one of the pack arguments per base class. Then the most derived class inherited all the friended base classes and implemented the interface. I cannot use this approach, since I need to protect the assignment operator, which is not inherited. Also, since the assignment operator has a defined signature with exactly one parameter, I cannot use a key pattern. This is what I would like to have:

问题 I have seen a CRTP solution, which extracted the interface into the base class, and friended only one of the pack arguments per base class. Then the most derived class inherited all the friended base classes and implemented the interface. I cannot use this approach, since I need to protect the assignment operator, which is not inherited. Also, since the assignment operator has a defined signature with exactly one parameter, I cannot use a key pattern. This is what I would like to have:

来源： https://stackoverflow.com/questions/64118868/base-case-specialization-for-recursive-variadic-template

来源： https://stackoverflow.com/questions/57622162/get-function-arguments-type-as-tuple