title: FluentValidation: Using a parent property value in a child collection rule
body: <p>I have this validator:</p>
  
  <pre><code> public class InputValidator : AbstractValidator&lt;InputData&gt;
  {
      public InputValidator()
      { 
          RuleFor(inputData =&gt; inputData.Ucl).GreaterThan(0).....;
  
          RuleForEach(inputData =&gt; inputData.Loads).ChildRules(inputData =&gt; {            
                inputData.RuleFor(load =&gt; load.Position).GreaterThan(0).....); 
              });
  ... etc
  </code></pre>
  
  <p>However: Position (in each load) must also be less than Ucl (in InputData).
  How can I make a rule for such a relation (parent parameter vs. child parameter)?</p>