title: VIM function to insert timestamp
body: <p>Someone in a previous question suggested the following for adding timestamps to VIM:</p>
  
  <pre><code>nmap &lt;F3&gt; a&lt;C-R&gt;=strftime("%Y-%m-%d %a %I:%M %p")&lt;CR&gt;&lt;Esc&gt;
  imap &lt;F3&gt; &lt;C-R&gt;=strftime("%Y-%m-%d %a %I:%M %p")&lt;CR&gt;
  </code></pre>
  
  <p>Instead of using F3, I'd like to insert the timestamp by executing a function instead. For example, typing :Now.</p>
  
  <p>Unfortunately, I don't grok VIM scripting. Can someone help?</p>