-annotation">E</span> <span class="parameter-name">previousValue</span>, </span> <span class="parameter" id="combine-param-element"><span class="type-annotation">E</span> <span class="parameter-name">element</span></span>)</span>)
            <span class="returntype parameter">&#8594; <a href="dart-core/double-class.html">double</a></span>
          </span>
                  </dt>
        <dd class="inherited">
          Reduces a collection to a single value by iteratively combining elements
of the collect