title: Using #include when initializing a constexpr (string ?)
body: <p>I came across this piece of code and I don't know how it works--I've never seen include used this way:</p>
  <pre><code>static constexpr auto VAR_NAME = 
      #include &quot;path/to/file/FileName&quot;
  ;
  </code></pre>
  <p>and the file path/to/file/FileName contains the contents of some string, i.e.</p>
  <pre><code>R&quot;(
  contents of string
  )&quot;
  </code></pre>
  <p>Could someone please explain what this code does?</p>