The key type
| 51 | // The key type |
| 52 | //************************************************************************* |
| 53 | struct Key |
| 54 | { |
| 55 | // Default constructor |
| 56 | constexpr Key() |
| 57 | : k(0) |
| 58 | { |
| 59 | } |
| 60 | |
| 61 | // Construct from char key |
| 62 | constexpr explicit Key(char k_) |
| 63 | : k(k_) |
| 64 | { |
| 65 | } |
| 66 | |
| 67 | char k; |
| 68 | }; |
| 69 | |
| 70 | // Less-than operator for Key < Key |
| 71 | constexpr bool operator<(const Key& lhs, const Key& rhs) noexcept |