title: vim - call function inside 'replace' expression
body: <p>I understand you can call a function in a vim search/replace operation.  For example:</p>
  
  <pre><code>%s/regex/\=localtime()/g
  </code></pre>
  
  <p>will replace anything matching 'regex' with the current epoch time.  The problem is, I can't add anything else to the 'replace' expression.  For example:</p>
  
  <pre><code>%s/regex/epoch: \=localtime()/g
  </code></pre>
  
  <p>does not treat 'localtime' as a function anymore.  Rather it just prints 'epoch: =localtime()' as a string in the replacement text. The intention is for it to print 'epoch: 1353085984' instead.</p>
  
  <p>Is there any way to call a function from within an arbitrary section of a replacement expression?</p>