+=head4 exception()
+
+ die $conn->exception();
+
+C<exception()> returns the same information as C<error_x()> in the
+form of a C<ZOOM::Exception> object which may be thrown or rendered.
+If no error occurred on the connection, then C<exception()> returns an
+undefined value.
+
+=head4 check()
+
+ $conn->check();
+
+Checks whether an error is pending on the connection, and throw a
+C<ZOOM::Exception> object if so. Since errors are thrown as they
+occur for synchronous connections, there is no need ever to call this
+except in asynchronous applications.
+