+ /** Save (a.k.a. serialize) object into archive. */
+ void archive(archive_node& n) const;
+ /** Read (a.k.a. deserialize) object from archive. */
+ void read_archive(const archive_node& n, lst& syms);
+ // non-virtual functions in this class
+protected:
+ unsigned return_type() const { return return_types::commutative; }
+ void do_print(const print_context & c, unsigned level) const;
+ void do_print_latex(const print_latex & c, unsigned level) const;
+