+//////////
+// archiving
+//////////
+
+/** Construct object from archive_node. */
+relational::relational(const archive_node &n, const lst &sym_lst) : inherited(n, sym_lst)
+{
+ debugmsg("relational constructor from archive_node", LOGLEVEL_CONSTRUCT);
+ unsigned int opi;
+ if (!(n.find_unsigned("op", opi)))
+ throw (std::runtime_error("unknown relational operator in archive"));
+ o = (operators)opi;
+ n.find_ex("lh", lh, sym_lst);
+ n.find_ex("rh", rh, sym_lst);
+}
+
+/** Unarchive the object. */
+ex relational::unarchive(const archive_node &n, const lst &sym_lst)
+{
+ return (new relational(n, sym_lst))->setflag(status_flags::dynallocated);
+}
+
+/** Archive the object. */
+void relational::archive(archive_node &n) const
+{
+ inherited::archive(n);
+ n.add_ex("lh", lh);
+ n.add_ex("rh", rh);
+ n.add_unsigned("op", o);
+}
+