/p>
<p> </p>
</div><p><p>
  Combines the operations of <code>map/2</code> and <code>foldl/3</code> into one pass.</p>
 
  Example:
  <pre>  &gt; % Summing the elements in an iterator and double them at the same time:
  &gt; DoubleAndSum = fun(X, Sum) -&gt; {2*X, X+Sum} end,
  &gt; {Mapped, Acc} = llists:mapfoldl(DoubleAndSum, 0, llists:seq(1,5)),
  &gt; {llists:to_list(Mapped), Acc}.
  {[2,4,6,8,10],15}</pre>
 
  The iterator is fully evaluated before the mapfold begins, infinite
  iterators will never retu