// utility functions
+
+/** Compare two objects of class quickly without doing a deep tree traversal.
+ * @return "true" if they are equal
+ * "false" if equality cannot be established quickly (e1 and e2 may
+ * still be equal, in this case. */
inline bool are_ex_trivially_equal(const ex &e1, const ex &e2)
{
return e1.bp == e2.bp;