title: laravel language key from variable
body: <p>Let's say I have this in <code>resource/lang/en/test.php</code> with this input</p>
  
  <pre><code>'testing.language.test' =&gt; 'testing'
  </code></pre>
  
  <p>then in the <code>index.blade.php</code> I would like to consume it with this method
  but not directly, instead I like to put it inside variable first then
  generate</p>
  
  <pre><code>&lt;p&gt;
  $var = 'testing.language.test';
  @lang('test' + $var);
  &lt;/p&gt;
  </code></pre>
  
  <p>but it's not working, it always returns the <code>testing.language.test</code> without parsing it from the language file.</p>