Method fixed_string

include/boost/ut.hpp:515–521

  CharT _data[N + 1] = {};

  constexpr explicit(false) fixed_string(const CharT (&str)[N + 1]) noexcept {
    if constexpr (N != 0) {
      for (std::size_t i = 0; i < N; ++i) {
        _data[i] = str[i];
      }
    }
  }

  [[nodiscard]] constexpr std::size_t size() const noexcept { return N; }
  [[nodiscard]] constexpr bool empty() const noexcept { return N == 0; }