diff --git a/schala-lang/language/src/ast.rs b/schala-lang/language/src/ast.rs
index bf77ef1..01cab96 100644
--- a/schala-lang/language/src/ast.rs
+++ b/schala-lang/language/src/ast.rs
@@ -160,17 +160,18 @@ pub enum Variant {
 
 #[derive(Debug, PartialEq, Clone)]
 pub struct Expression {
+  pub id: ItemId,
   pub kind: ExpressionKind,
   pub type_anno: Option<TypeIdentifier>
 }
 
 impl Expression {
-  pub fn new(kind: ExpressionKind) -> Expression {
-    Expression { kind, type_anno: None }
+  pub fn new(id: ItemId, kind: ExpressionKind) -> Expression {
+    Expression { id, kind, type_anno: None }
   }
 
-  pub fn with_anno(kind: ExpressionKind, type_anno: TypeIdentifier) -> Expression {
-    Expression { kind, type_anno: Some(type_anno) }
+  pub fn with_anno(id: ItemId, kind: ExpressionKind, type_anno: TypeIdentifier) -> Expression {
+    Expression { id, kind, type_anno: Some(type_anno) }
   }
 }