title: Regex.Matches using lookahead not getting any matches
body: <p>I have a Regex</p>
  
  <pre><code>Regex.Matches(a, @"((?=.)\1+)")
  </code></pre>
  
  <p>The above regex should get matches without capturing pattern obliged results</p>
  
  <p>But it does not fetch any matches</p>
  
  <p>On the other hand when I use it without lookahead</p>
  
  <p>like this</p>
  
  <pre><code> Regex.Matches(a, @"(.)\1+")
  </code></pre>
  
  <p>It brings matches and working fine</p>
  
  <p>I like to know why is this, why lookahead not fetching any matches.</p>
  
  <p>My string is</p>
  
  <pre><code>   "zaaaaaaashjasjaaasjabbbajsljlsccccasjahsddddd";
  </code></pre>
  
  <p>the second line above brings  </p>
  
  <pre><code>  [aaaaaaa],[aaa],...
  </code></pre>
  
  <p>Thanks</p>