diff --git a/include/anthem/ASTVisitors.h b/include/anthem/ASTVisitors.h
index f651741..b7c8658 100644
--- a/include/anthem/ASTVisitors.h
+++ b/include/anthem/ASTVisitors.h
@@ -14,6 +14,7 @@ namespace ast
 //
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
+// TODO: refactor
 template<class T>
 struct RecursiveFormulaVisitor
 {