ing value.
  <strong>nextPartialResult:</strong> A closure that combines an accumulating
    value and an element of the sequence into a new accumulating
    value, to be used in the next call of the
    <code>nextPartialResult</code> closure or returned to the caller.
<strong>Returns:</strong> The final accumulated value.</p>

    <h4>Declaration</h4>    
    <code class="language-swift">func reduce&lt;Result&gt;(_ initialResult: Result, _ nextPartialResult: (Result, Iterator.Element) throws -&gt; Result) 