title: How to simplify composite type in variable
body: <p>I'm looping through some input and output strings for a unit test, and my first attempt was:</p>
  
  <pre><code>std::vector&lt;std::pair&lt;std::string, std::string&gt;&gt; pairs {{"input1", "output1"}, {"input2", "output2"}};
  </code></pre>
  
  <p>As you can see it's quite verbose. I've tried to use <code>auto</code>, but g++ complains about the nested init lists.</p>
  
  <p>How can this be simplified?</p>
  
  <p>I realize this might not be the recommended data structure for the job (you could use a <code>std::map</code> for instance) I'm asking this out of pure curiosity.</p>