diff --git a/nac3core/src/toplevel/composer.rs b/nac3core/src/toplevel/composer.rs
index 68cfb72..8e612a6 100644
--- a/nac3core/src/toplevel/composer.rs
+++ b/nac3core/src/toplevel/composer.rs
@@ -563,7 +563,6 @@ impl TopLevelComposer {
                         &primitive_types,
                         b,
                         vec![(*class_def_id, class_type_vars.clone())].into_iter().collect(),
-                        None,
                     )?;
 
                     if let TypeAnnotation::CustomClass { .. } = &base_ty {
@@ -904,7 +903,6 @@ impl TopLevelComposer {
                             // NOTE: since only class need this, for function
                             // it should be fine to be empty map
                             HashMap::new(),
-                            None,
                         )?;
 
                         let type_vars_within =
@@ -971,7 +969,6 @@ impl TopLevelComposer {
                             // NOTE: since only class need this, for function
                             // it should be fine to be empty map
                             HashMap::new(),
-                            None,
                         )?
                     };
 
@@ -1158,7 +1155,6 @@ impl TopLevelComposer {
                                         vec![(class_id, class_type_vars_def.clone())]
                                             .into_iter()
                                             .collect(),
-                                        None,
                                     )?
                                 };
                                 // find type vars within this method parameter type annotation
@@ -1224,7 +1220,6 @@ impl TopLevelComposer {
                                 primitives,
                                 result,
                                 vec![(class_id, class_type_vars_def.clone())].into_iter().collect(),
-                                None,
                             )?;
                             // find type vars within this return type annotation
                             let type_vars_within =
@@ -1319,7 +1314,6 @@ impl TopLevelComposer {
                                 primitives,
                                 annotation.as_ref(),
                                 vec![(class_id, class_type_vars_def.clone())].into_iter().collect(),
-                                None,
                             )?;
                             // find type vars within this return type annotation
                             let type_vars_within =
diff --git a/nac3core/src/toplevel/type_annotation.rs b/nac3core/src/toplevel/type_annotation.rs
index d44597c..3cd2f25 100644
--- a/nac3core/src/toplevel/type_annotation.rs
+++ b/nac3core/src/toplevel/type_annotation.rs
@@ -74,7 +74,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
     expr: &ast::Expr<T>,
     // the key stores the type_var of this topleveldef::class, we only need this field here
     locked: HashMap<DefinitionId, Vec<Type>>,
-    type_var: Option<Type>,
 ) -> Result<TypeAnnotation, HashSet<String>> {
     let name_handle = |id: &StrRef,
                        unifier: &mut Unifier,
@@ -195,7 +194,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                                 locked.insert(obj_id, type_vars.clone());
                                 locked.clone()
                             },
-                            None,
                         )
                     })
                     .collect::<Result<Vec<_>, _>>()?;
@@ -231,7 +229,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                 primitives,
                 slice.as_ref(),
                 locked,
-                None,
             )?;
             if !matches!(def, TypeAnnotation::CustomClass { .. }) {
                 unreachable!("must be concretized custom class kind in the virtual")
@@ -252,7 +249,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                 primitives,
                 slice.as_ref(),
                 locked,
-                None,
             )?;
             Ok(TypeAnnotation::List(def_ann.into()))
         }
@@ -270,7 +266,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                 primitives,
                 slice.as_ref(),
                 locked,
-                None,
             )?;
             let id =
                 if let TypeEnum::TObj { obj_id, .. } = unifier.get_ty(primitives.option).as_ref() {
@@ -304,7 +299,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                         primitives,
                         e,
                         locked.clone(),
-                        None,
                     )
                 })
                 .collect::<Result<Vec<_>, _>>()?;
@@ -337,7 +331,6 @@ pub fn parse_ast_to_type_annotation_kinds<T>(
                             primitives,
                             e,
                             locked.clone(),
-                            None,
                         ),
                     }
                 })
diff --git a/nac3standalone/src/main.rs b/nac3standalone/src/main.rs
index f34f55a..eb746a8 100644
--- a/nac3standalone/src/main.rs
+++ b/nac3standalone/src/main.rs
@@ -104,7 +104,6 @@ fn handle_typevar_definition(
                         primitives,
                         x,
                         HashMap::default(),
-                        None,
                     )?;
                     get_type_from_type_annotation_kinds(
                         def_list, unifier, &ty, &mut None
@@ -146,7 +145,6 @@ fn handle_typevar_definition(
                 primitives,
                 &args[1],
                 HashMap::default(),
-                None,
             )?;
             let constraint = get_type_from_type_annotation_kinds(
                 def_list, unifier, &ty, &mut None