std::experimental::to_array
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Library fundamentals v2
experimental::to_array | ||||
 | Merged into ISO C++ The functionality described on this page was merged into the mainline ISO C++ standard as of 7/2019, seestd::to_array(since C++20) |
Defined in header <experimental/array> | ||
template<class T,std::size_t N> constexprstd::array<std::remove_cv_t<T>, N> to_array(T(&a)[N]); | (library fundamentals TS v2) | |
Creates astd::array from the built-in arraya. The elements of thestd::array are copy-initialized from the corresponding element ofa.
Contents |
[edit]Parameters
| a | - | the built-in array to be used to initialize thestd::array |
[edit]Return value
Anstd::array object whose elements are copy-initialized from the corresponding element ofa.
[edit]Possible implementation
namespace detail{template<class T,std::size_t N,std::size_t...I>constexprstd::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>constexprstd::array<std::remove_cv_t<T>, N> to_array(T(&a)[N]){return detail::to_array_impl(a,std::make_index_sequence<N>{});} |
[edit]Example
Run this code
#include <cassert>#include <cstdlib>#include <experimental/array>#include <unistd.h> // mkstemp(3) that workstemplate<std::size_t N>int tempfd(charconst(&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);}
[edit]See also
(library fundamentals TS v2) | creates astd::array object whose size and optionally element type are deduced from the arguments (function template)[edit] |
