@Override
 public void visitClosureReference(ClosureReference closureReference) {
   closureReference.getTarget().accept(this);
   if (closureReference.getTarget().isSynthetic()) {
     Context context = context();
     if (context != null) {
       for (String refName : closureReference.getTarget().getParameterNames()) {
         ReferenceTable referenceTable = context.referenceTableStack.peek();
         if (referenceTable.hasReferenceFor(refName)) {
           // ...else it's a regular parameter
           accessed(refName);
         }
       }
     }
   }
 }
 @Override
 public void visitAssignmentStatement(AssignmentStatement assignmentStatement) {
   LocalReference localReference = assignmentStatement.getLocalReference();
   String referenceName = localReference.getName();
   if (!localReference.isModuleState()) {
     if (!stack.isEmpty()) {
       assignmentStatement.setLocalReference(
           context().referenceTableStack.peek().get(referenceName));
     }
     if (assignmentStatement.isDeclaring()) {
       locallyDeclared(referenceName);
     }
   } else {
     locallyDeclared(referenceName);
   }
   locallyAssigned(referenceName);
   assignmentStatement.getExpressionStatement().accept(this);
   if (assignmentStatement.getExpressionStatement() instanceof ClosureReference) {
     ClosureReference closure = (ClosureReference) assignmentStatement.getExpressionStatement();
     GoloFunction target = closure.getTarget();
     if (target.getSyntheticParameterNames().contains(referenceName)) {
       target.removeSyntheticParameter(referenceName);
       target.setSyntheticSelfName(referenceName);
     }
   }
 }