diff --git a/src/parser/nom_context.rs b/src/parser/nom_context.rs
index 60ba9def..f8152e45 100644
--- a/src/parser/nom_context.rs
+++ b/src/parser/nom_context.rs
@@ -10,13 +10,13 @@ use nom::Parser;
 type Link<'r, T> = Option<&'r Node<'r, T>>;
 type Matcher = dyn for<'s> Fn(&'s str) -> IResult<&'s str, &'s str, VerboseError<&'s str>>;
 
-pub struct Node<'r, T> {
+struct Node<'r, T> {
     elem: T,
     next: Link<'r, T>,
 }
 
 pub struct List<'r, T> {
-    head: Link<'r, T>,
+    head: Option<Node<'r, T>>,
 }
 
 impl<'r, T> List<'r, T> {
@@ -24,13 +24,15 @@ impl<'r, T> List<'r, T> {
         List { head: None }
     }
 
-    pub fn with_additional_node(&self, element: T) -> Node<'r, T> {
+    pub fn with_additional_node(&'r self, element: T) -> List<'r, T> {
         let new_node = Node {
             elem: element,
-            next: self.head,
+            next: self.head.as_ref(),
         };
 
-        new_node
+        List {
+            head: Some(new_node),
+        }
     }
 }