title: Fugitive commands unavailable after opening .vimrc to edit
body: <p>My system is an OS X 10.6 with MacVim 7.3 (GUI) and Vim 7.2 (on iTerm).</p>
  
  <p>On MacVim, Fugitive does not work at all.</p>
  
  <p>On Vim, it is a little bit different. I have set a mapping to open the <code>.vimrc</code> file as follows:</p>
  
  <pre><code>nmap &lt;silent&gt; &lt;leader&gt;ev :e $MYVIMRC&lt;CR&gt;
  </code></pre>
  
  <p>Just after opening vim, all Fugitive commands are available, but after opening the <code>.vimrc</code> file using the mapping above I can't issue any of the Fugitive <code>:G*</code> commands. If I open the <code>.vimrc</code> file normally (i.e. with <code>:e ~/.vimrc</code>) everything is fine.</p>
  
  <p>My entire <code>.vim</code> dir (with <code>.vimrc</code> as <code>vimrc</code> in the root) can be accessed <a href="https://github.com/freitass/vimfiles" rel="nofollow">here</a>.</p>
  
  <p>What can I do to make it work?</p>