title: Will First() perform the OrderBy()?
body: <p>Is there any difference in (asymptotic) performance between</p>
  
  <pre><code>var a = Orders.OrderBy(order =&gt; order.Date).First()
  </code></pre>
  
  <p>and</p>
  
  <pre><code>var y = Orders.Where(order =&gt; order.Date == Orders.Min(x =&gt; x.Date)).ToList();
  </code></pre>
  
  <p>i.e. will First() perform the OrderBy()? I'm guessing no. <a href="http://msdn.microsoft.com/en-us/library/bb301450.aspx" rel="noreferrer">MSDN</a> says enumerating the collection via foreach och GetEnumerator does but the phrasing does not exclude other extensions.</p>