anchor.diff:        childItem=claimName               {if (childItem != null) children.add(childItem);}
         "in"
         childItem=scTerm[null]            {if (childItem != null) children.add(childItem);}
  -      //ignore=fullURIPath
         (childItem=proverAssertions)?     {if (childItem != null) children.add(childItem);}
         (childItem=proverOptions)?        {if (childItem != null) children.add(childItem);}
                                           {proof = builder.createProof(name);
  
positive.code: {
      name = null;
  }
      : name=idName
      | sym:NON_WORD_SYMBOL           {name=sym.getText();}
      | translate:"translate"         {name="translate";}
      | colimit:"colimit"             {name="colimit";}
      | diagram:"diagram"             {name="diagram";}
  
negative.code:     ;
  
  private quotientPattern
      : "quotient" expression tightPattern
      ;
  
  // expressions ---------------------------------------------------------------------------
  