r-2">filter/2</a></td><td>
  <code>Filtered</code> is an iterator of all elements <code>Elem</code> in <code>Iterator1</code> for
  which <code>Pred(Elem)</code> returns <code>true</code>.</td></tr>
<tr><td valign="top"><a href="#filtermap-2">filtermap/2</a></td><td>
  Calls <code>Fun(Elem)</code> on successive elements <code>Elem</code> of <code>Iterator1</code>.</td></tr>
<tr><td valign="top"><a href="#flatlength-1">flatlength/1</a></td><td>
  Equivalent to <code>length(flatten(DeepIterator))</code>.</td>