finity' as values and to be able to return infinite
   iterators.</li>
   <li>On error, the same exception should be raised, though it may
   not be raised until the triggering element of an iterator is
   evaluated.</li>
   <li>Iteration evaluation behaviour is documented.</li>
   </ul>
  
   As few functions outside of <code>lists</code> have been implemented as
   possible in order to have the best chance of keeping the namespace
   clean for future additions to the <code>lists</code> module. New
   func