+inline bool operator ==(const Block &a, const Block &b) {
+ return a.type == b.type && a.orient == b.orient;
+}
+
+inline bool operator !=(const Block &a, const Block &b) {
+ return !(a == b);
+}
+
+std::ostream &operator <<(std::ostream &, const Block &);
+std::ostream &operator <<(std::ostream &, const Block::Face &);
+std::ostream &operator <<(std::ostream &, const Block::Turn &);
+