title: php heredoc variable in compound word
body: <p>I would like to create a compound word using a variable and hard coded text.
  E.g. When passing User as the $model argument to below function:</p>
  
  <pre><code>function compileRepository($model) {
      return &lt;&lt;&lt;TEMPLATE
      &lt;?php
  
      namespace App\Repositories\Eloquent;
  
      use App\Models\Eloquent\\$model;
      use App\Interfaces\\$model as $modelInterface;
  
      class Eloquent$model implements $modelInterface {
  
      };
      TEMPLATE;
      }
  </code></pre>
  
  <p>I would like to get:</p>
  
  <pre><code>    &lt;?php
  
      namespace App\Repositories\Eloquent;
  
      use App\Models\Eloquent\User;
      use App\Interfaces\User as UserInterface;
  
      class EloquentUser implements UserInterface {
  
      };
  </code></pre>
  
  <p>Unfortunately this does not work because $modelInterface is interpreted as the variable modelInterface rather than the variable $model concatenated with Interface</p>