c++ - Efficient way to convert/reinterpret vector<T> as vector<array<T, 1>> -


i want call method (template) takes vector<array<t, n>>& result method returns vector<t>

is there efficient (o(1)) way reinterpret vector<t> vector<array<t,1>>? possible / safe reinterpret_cast it?

if t std::array<u,1>you should able template deduction , overloading:

template <typename t> std::vector<t> myfunc() { return {t{1}}; }  template <typename t> void myotherfunc(std::vector<t>) { cout << "not array\n"; }  template <typename t, size_t n> void myotherfunc(std::vector<std::array<t,n>>) { cout << "an array\n"; }

then calling this:

myotherfunc(myfunc<int>()); //prints "not array" myotherfunc(myfunc<std::array<int,1>>()); //prints "an array"

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