title: Dangling topic (or any other) variable does not fail
body: <p>This works:</p>
  
  <pre><code>$_ =
  
  say "hi";
  </code></pre>
  
  <p>That is, you can put any amount of whitespace between an assignment and stuff that's behind, it will simply ignore it. You can use any variable (with <code>my</code>) too. Effectively, $_ will be assigned the result of the <code>say</code>, which is <code>True</code>.</p>
  
  <p>Is this surprising, but up to spec, or simply surprising?</p>