deduction guides for std::array

template <class T, class... U>
array(T, U...) -> array<T, 1 + sizeof...(U)>;

One deduction guide is provided for std::array to provide an equivalent of std::experimental::make_array for construction of std::array from a variadic parameter pack.

The program is ill-formed if (std::is_same_v<T, U> && ...) is not true.

Example

#include <array>
int main()
{
    int const x = 10;
    std::array a{1, 2, 3, 5, x}; // OK, creates std::array<int, 5>
 
//  std::array b{1, 2u}; // Error, all arguments must have same type
}