| 199 | constexpr value_type &front() const noexcept { return data_[0]; } |
| 200 | constexpr value_type &back() const noexcept { return data_[extent - 1]; } |
| 201 | constexpr bool empty() const noexcept { return extent == 0; } |
| 202 | |
| 203 | template <typename same_value_type_ = value_type, |
| 204 | typename = typename std::enable_if<!std::is_const<same_value_type_>::value>::type> |
no outgoing calls