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std::experi...al::to_array(3)  C++ Standard Libary std::experi...al::to_array(3)

NAME
     std::experimental::to_array - std::experimental::to_array

Synopsis
	Defined in header <experimental/array>
	template<  class  T,  std::size_t  N >				(library
     fundamentals TS
	constexpr std::array<std::remove_cv_t<T>, N> to_array(T     v2)
	(&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 corre-
     sponding
	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 <cassert>
      #include <cstdlib>
      #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
	make_array		      creates a std::array object whose size and
     optionally
	(library fundamentals TS v2) element type are deduced from the arguments
				     (function template)

http://cppreference.com 	   2024.06.10	   std::experi...al::to_array(3)
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