title: NSNumberFormatter not returning nilSymbol on nil value. What am I missing?
body: <p>iOS 4+; when I pass a nil value to my NSNumberFormatter I want the nil symbol that was set (NSString *) in return.  It works for the 'zero' symbol, but not for the nil symbol.  I've tried many different configuration settings like behavior, grouping, etc.</p>
  <pre><code>fmtr = [[NSNumberFormatter alloc] init];
  
  [fmtr setNumberStyle:NSNumberFormatterDecimalStyle];
  
  [fmtr setFormatterBehavior:NSNumberFormatterBehaviorDefault];
  
  [fmtr setUsesGroupingSeparator:NO];
  
  [fmtr setNilSymbol:@&quot;###&quot;];
  
  [fmtr setZeroSymbol:@&quot;0000&quot;];
  
             
  NSLog(@&quot;[fmtr nilSymbol]=&gt;&gt;%@&lt;&lt;&quot;, [fmtr nilSymbol]);
  
  NSLog(@&quot;[fmtr stringFromNumber:nil]=&gt;&gt;%@&lt;&lt;  this should be '###&quot;, [fmtr stringFromNumber:nil] );
  
  NSLog(@&quot;[fmtr stringFromNumber:0]=&gt;&gt;%@&lt;&lt;&quot;, [fmtr stringFromNumber:[NSNumber numberWithInt:0]] );
  
  NSLog(@&quot;[fmtr stringFromNumber:null]=&gt;&gt;%@&lt;&lt;&quot;, [fmtr stringFromNumber:NULL] );
  
  NSLog(@&quot;[fmtr numberFromString:nil]=%@&quot;, [fmtr numberFromString:nil] );
  
  NSLog(@&quot;[fmtr numberFromString:@\&quot;0\&quot;]=%@&quot;, [fmtr numberFromString:@&quot;0&quot;] );
  
  NSLog(@&quot;[fmtr numberFromString:NULL]=%@&quot;, [fmtr numberFromString:NULL] );
  </code></pre>
  <p>Here is the output of the test:</p>
  <blockquote>
  <p>[fmtr nilSymbol]=&gt;&gt;###&lt;&lt;</p>
  <p>[fmtr stringFromNumber:nil]=&gt;&gt;(null)&lt;&lt;  this should be '###</p>
  <p>[fmtr stringFromNumber:0]=&gt;&gt;0000&lt;&lt;</p>
  <p>[fmtr stringFromNumber:null]=&gt;&gt;(null)&lt;&lt;</p>
  <p>[fmtr numberFromString:nil]=(null)</p>
  <p>[fmtr numberFromString:@&quot;0&quot;]=0</p>
  <p>[fmtr numberFromString:NULL]=(null)</p>
  </blockquote>