a></tt></li><li><tt>Iterator = <a href="#type-iterator">iterator</a>(Elem)</tt></li></ul></p>
<p> </p>
</div><p>
  Construct a new iterator from a <code>Fun(AccIn)</code> function and an
  initial accumulator value <code>Acc0</code>. When an element is demanded of
  the iterator, <code>Fun</code> will be invoked with the current accumulator to
  produce a value. <code>Fun</code> is expected to return a tuple of
  <code>{Elem, AccOut}</code>: the element to produce and the new accumulator
  value. If iterati