title: Cross reference to multiple names in the same grammar rule
body: <p>In my DSL, I have two different rules that can be used to define entities:</p>
  
  <p>First way is by a preset word followed by the name of the entity:</p>
  
  <pre><code>Actor Bob
  
  Actor Alice
  </code></pre>
  
  <p>Second way is by creating a relation between two entities:</p>
  
  <pre><code>Bob -&gt; Alice
  </code></pre>
  
  <p>Which would be the same as writing</p>
  
  <pre><code>Actor Bob -&gt; Actor Alice
  </code></pre>
  
  <p>Now I have a question when it comes to the cross referencing of these entities. Creating a cross reference to the Actors are easy, as I just reference the rule</p>
  
  <pre><code>Actor: 
  'Actor' name = ID
  </code></pre>
  
  <p>But what happens when I have two ID's in the same rule? How would I go about cross referencing</p>
  
  <pre><code>Arrow:
  'Actor'? name+=ID '-&gt;' 'Actor'? name+=ID
  </code></pre>
  
  <p>Since there are several names in the same rule?</p>
  
  <p>Thanks!</p>