if <code>Pred(Elem)</code> returns <code>true</code> for at least one
  element <code>Elem</code> in <code>Iterator</code>.</td></tr>
<tr><td valign="top"><a href="#append-1">append/1</a></td><td>
  Returns an iterator in which all the subiterators of
  <code>IteratorOfIterators</code> have been appended.</td></tr>
<tr><td valign="top"><a href="#append-2">append/2</a></td><td>
  Returns a new iterator <code>Iterator3</code>, which is made from the elements
  of <code>Iterator1</code> followed by the element