title: Is it possible to assign default values to NAnt properties?
body: <p>I'd like to use the property value as a part of an argument passed to a certain EXE via <code>&lt;exec/&gt;</code> task. There's a condition which influences the property initialization, that is, if condition is true, it should contain value, otherwise be just empty (but still defined).</p>
  
  <p>This is what I ended up so far:</p>
  
  <pre><code>&lt;property name="prop1" value="" /&gt;
  &lt;property name="prop1" value="some-value-based-on-condition" if="condition-goes-here" /&gt;
  </code></pre>
  
  <p>And later on:</p>
  
  <pre><code>&lt;exec program="my.exe"&gt;
    &lt;arg value="C:\Root\Folder\${prop1}" /&gt;
    ...
  &lt;/exec&gt;
  </code></pre>
  
  <p>If the property is not set, I'd like to pass just <code>C:\Root\Folder\</code> as an argument value.</p>
  
  <p>Initializing the property in this way seems too much for such a simple operation. Is there a way to do it simpler using what's in NAnt at the moment? I would imagine something like:</p>
  
  <pre><code>&lt;property name="prop1" value="somevalue-based-on-condition" if="condition" default="" /&gt;
  </code></pre>