title: What is the easiest way to swap occurrences of two strings in Vim?
body: <p>What is the easiest way to replace all occurrences of <code>string_a</code> with <code>string_b</code> while at the same time changing anything that was already <code>string_b</code> into <code>string_a</code>? My current method is as follows:</p>
  
  <pre><code>:s/string_a/string_c/g  
  :s/string_b/string_a/g  
  :s/string_c/string_b/g  
  </code></pre>
  
  <p>Although this works, it requires extra typing and seems inefficient. Does anybody know of a better way to do this?</p>