Function strcpy

gil/std.str.hpp:51–55

}

static constexpr auto strcpy(auto dst, auto src) noexcept {
  using _impl_::idx;
  return for_(idx = 0, true, ++idx)(dst[*idx] = *src[*idx],
                                    if_(end(src[*idx]))(break_));
}

static constexpr auto puts(auto str) noexcept {
  using _impl_::idx;