 ```
  &gt; llists:to_list(
       llists:enumerate(0,
           llists:from_list([one, two, three]))).
  [{0,one},{1,two},{2,three}]</pre></p>

<h3 class="function"><a name="filter-2">filter/2</a></h3>
<div class="spec">
<p><tt>filter(Pred, Iterator1) -&gt; Iterator2</tt>
<ul class="definitions"><li><tt>Pred = <a href="#type-predicate">predicate</a>(Elem)</tt></li><li><tt>Iterator1 = <a href="#type-iterator">iterator</a>(Elem)</tt></li><li><tt>Iterator2 = <a href="#type-iterator">iterator</a>(Elem)</tt></