title: What is the purpose of the parentheses in Perl's `foreach` statement?
body: <p>I always wonder why I must write</p>
  
  <pre><code>foreach my $x (@arr)
  </code></pre>
  
  <p>instead of </p>
  
  <pre><code>foreach my $x @arr
  </code></pre>
  
  <p>What is the purpose of the parentheses here?</p>