gt; deferredFunction)     <br />{     <br />&#160;&#160;&#160; ThrowingEnumerable source = <span class="Keyword">new</span> ThrowingEnumerable();     <br />&#160;&#160;&#160; <span class="Linq">var</span> result = deferredFunction(source);     <br />&#160;&#160;&#160; <span class="Namespace">using</span> (<span class="Linq">var</span> iterator = result.GetEnumerator())     <br />&#160;&#160;&#160; {     <br />&#160;&#160;&#160;&#160;&#160;&#160;&#160; Assert.Throws&lt;InvalidOperationException&gt;(() =&gt; 