我的问题在于代码:
template<typename... Ts>
struct TupleOfVectors {
std::tuple<std::vector<Ts>...> tuple;
void do_something_to_each_vec() {
//Question: I want to do this:
// "for each (N)": do_something_to_vec<N>()
//How?
}
template<size_t N>
void do_something_to_vec() {
auto &vec = std::get<N>(tuple);
//do something to vec
}
};
Run Code Online (Sandbox Code Playgroud) 如何反转元组中的类型?例如,我想reverse_tuple<std::tuple<int, char, bool>>::type成为std::tuple<bool, char, int>.我尝试了以下但是没有用.我做错了什么?
#include <type_traits>
#include <tuple>
template <typename... Ts>
struct tuple_reverse;
template <typename T, typename... Ts>
struct tuple_reverse<std::tuple<T, Ts...>>
{
using type = typename tuple_reverse<
std::tuple<
typename tuple_reverse<std::tuple<Ts..., T>>::type
>
>::type;
};
template <typename T>
struct tuple_reverse<std::tuple<T>>
{
using type = std::tuple<T>;
};
int main()
{
using result_type = std::tuple<int, bool, char>;
static_assert(
std::is_same<
tuple_reverse<var>::type, std::tuple<char, bool, int>
>::value, ""
);
}
Run Code Online (Sandbox Code Playgroud)
这是我的错误:
prog.cpp: In instantiation of ‘struct tuple_reverse<std::tuple<char, int, bool> >’:
prog.cpp:15:34: …