ar>iteratorRecord</var>).</li><li>If <var>next</var> is <emu-val>false</emu-val>, return <var>map</var>.</li><li>Let <var>item</var> be ?&nbsp;IteratorValue(<var>next</var>).</li><li>Let <var>key</var> be Call(<var>callbackfn</var>, <emu-val>null</emu-val>, « <var>item</var>&nbsp;»)</li><li>Let <var>status</var> be Call(<var>set</var>, <var>map</var>, « <var>key</var>.<var class="field">[[Value]]</var>, <var>value</var>.<var class="field">[[Value]]</var>&nbsp;»).</li><li>If <var>status</var> is an abrup