title: Catching an undefined message in ObjC and forward it to a method with a different signature
body: <p>I'm writing a logger class (who doesn't ?) with a method </p>
  
  <pre><code>- (void) logWithTag:(NSString *)aTag andMessage:(NSString *)aMsg;
  </code></pre>
  
  <p>I wish to be able to forward undefined messages to this method. For example  : </p>
  
  <pre><code>[myLogger logFoo:@"bar"] should call [myLogger logWithTag:@"Foo" andMessage:@"bar"]
  </code></pre>
  
  <p>and more generically </p>
  
  <pre><code>[myLogger logXXX:@"bar"] should call [myLogger logWithTag:@"XXX" andMessage:@"bar"]
  </code></pre>
  
  <p>I've looked at <code>resolveInstanceMethod</code> and message forwarding, but from what I understood, they all expect the method to have the same signature.</p>
  
  <p>Any idea ?
  thanks !</p>