std::experimental::to_array (3) Linux Manual Page

std::experimental::to_array – std::experimental::to_array

Synopsis

Defined in header <experimental/array>

template <class T, std::size_t N>                                  (library fundamentals TS v2)

constexpr std::array<std::remove_cv_t<T>, N> to_array(T (&a)[N]);

Creates a std::array from the built-in array a. The elements of the std::array are copy-initialized from the corresponding element of a.

Parameters

a – the built-in array to be used to initialize the std::array

Return value

An std::array object whose elements are copy-initialized from the corresponding element of a.

Possible implementation

  namespace detail {
  template <class T, std::size_t N, std::size_t… I>
  constexpr std::array<std::remove_cv_t<T>, N>
      to_array_impl(T (&a)[N], std::index_sequence<I…>)
  {
      return { {a[I]…} };
  }
  }

  template <class T, std::size_t N>
  constexpr std::array<std::remove_cv_t<T>, N> to_array(T (&a)[N])
  {
      return detail::to_array_impl(a, std::make_index_sequence<N>{});
  }

Example

// Run this code

#include <cstdlib>

#include <cassert>

#include <experimental/array>

#include <unistd.h>
// mkstemp(3) that works

template <std::size_t N>

int tempfd(char const (&tmpl)[N])

{
    auto s = std::experimental::to_array(tmpl);
    int fd = mkstemp(s.data());
    if (fd != -1)
        unlink(s.data());
    return fd;
}
int main()

{
    int fd = tempfd("/tmp/test.XXXXXX");
    int rt = close(fd);
    assert(rt == 0);
}

See also

           Creates a std::array object whose size and optionally element type are deduced from the arguments
make_array (function template)