title: How to use SET FILTER TO in FoxPro to limit the results to matched records in another cursor
body: <p>Say, I've got a cursor with data records, with an identifying foreign key in <code>csrData</code>:</p>
  
  <pre><code>|  ID  |  Foreign_ID  |  
  |  1   |  1           |  
  |  2   |  1           |  
  |  3   |  2           |  
  |  4   |  2           |  
  |  5   |  2           |  
  |  6   |  3           |  
  </code></pre>
  
  <p>And a list of foreign IDs in a separate cursor <code>csrMatches</code>:</p>
  
  <pre><code>|  Match_Foreign_ID  |  
  |  1                 |  
  |  3                 |  
  </code></pre>
  
  <p>Is there a SET FILTER TO command I can issue against <code>csrData</code> to get:</p>
  
  <pre><code>|  ID  |  Foreign_ID  |  
  |  1   |  1           |  
  |  2   |  1           |  
  |  6   |  3           |  
  </code></pre>
  
  <p>I know this can be achieved using a SQL query, but the reporting framework I'm using limits me to <code>SET FILTER TO</code> statements.  The <code>INLIST()</code> function works similarly, but I'd like to do filtering against a set of unknown size.</p>