title: Delphi 7 prescience of class helpers
body: <p>Today I happened to compile, using Delphi 7, a code with a class definition like this</p>
  
  <pre><code>type TAudioStream = class helper of TStream;
  </code></pre>
  
  <p>and, to my astonishment, the compiler spits </p>
  
  <p><em>"System unit out of date or corrupted: missing 'TClassHelperBase'"</em>. </p>
  
  <p>It looks like Delphi7 has already some reserved usage of the <code>helper</code> word.</p>
  
  <p>Delphi introduced Helper classes in Delphi 8. They were intended for binding VCL to .Net. So, is Delphi7 prescient? </p>