diff --git a/src/main.rs b/src/main.rs
index d8ad52f..2d08c63 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -121,48 +121,52 @@ fn handle_typevar_definition(
 fn handle_assignment_pattern(
     targets: &[nac3parser::ast::Expr],
     value: &nac3parser::ast::Expr,
-    resolver: &(dyn nac3core::symbol_resolver::SymbolResolver + Send + Sync),
+    resolver: Arc<dyn nac3core::symbol_resolver::SymbolResolver + Send + Sync>,
     internal_resolver: &ResolverInternal,
-    def_list: &[Arc<RwLock<toplevel::TopLevelDef>>],
-    unifier: &mut nac3core::typecheck::typedef::Unifier,
-    primitives: &type_inferencer::PrimitiveStore,
+    composer: &mut composer::TopLevelComposer,
 ) -> Result<(), String> {
     if targets.len() == 1 {
-        match &targets[0].node {
+        let target = &targets[0];
+
+        match &target.node {
             nac3parser::ast::ExprKind::Name { id, .. } => {
+                let def_list = composer.extract_def_list();
+                let unifier = &mut composer.unifier;
+                let primitives = &composer.primitives_ty;
+
                 if let Ok(var) =
-                    handle_typevar_definition(value, resolver, def_list, unifier, primitives)
+                    handle_typevar_definition(value, &*resolver, &def_list, unifier, primitives)
                 {
                     internal_resolver.add_id_type(*id, var);
                     Ok(())
-                } else if let Ok(val) =
-                    toplevel::helper::parse_parameter_default_value(value, resolver)
-                {
+                } else if let Ok(val) = toplevel::helper::parse_parameter_default_value(value, &*resolver) {
                     internal_resolver.add_module_global(*id, val);
+                    let (name, def_id, _) = composer
+                        .register_top_level_var(
+                            *id,
+                            None,
+                            Some(resolver.clone()),
+                            "__main__",
+                            target.location,
+                        )
+                        .unwrap();
+                    internal_resolver.add_id_def(name, def_id);
                     Ok(())
                 } else {
                     Err(format!("fails to evaluate this expression `{:?}` as a constant or generic parameter at {}",
-                        targets[0].node,
-                        targets[0].location,
+                        target.node,
+                        target.location,
                     ))
                 }
             }
             nac3parser::ast::ExprKind::List { elts, .. }
             | nac3parser::ast::ExprKind::Tuple { elts, .. } => {
-                handle_assignment_pattern(
-                    elts,
-                    value,
-                    resolver,
-                    internal_resolver,
-                    def_list,
-                    unifier,
-                    primitives,
-                )?;
+                handle_assignment_pattern(elts, value, resolver, internal_resolver, composer)?;
                 Ok(())
             }
             _ => Err(format!(
-                "assignment to {:?} is not supported at {}",
-                targets[0], targets[0].location
+                "assignment to {target:?} is not supported at {}",
+                target.location
             )),
         }
     } else {
@@ -174,11 +178,9 @@ fn handle_assignment_pattern(
                         handle_assignment_pattern(
                             std::slice::from_ref(tar),
                             val,
-                            resolver,
+                            resolver.clone(),
                             internal_resolver,
-                            def_list,
-                            unifier,
-                            primitives,
+                            composer,
                         )?;
                     }
                     Ok(())
@@ -202,8 +204,9 @@ fn handle_assignment_pattern(
 fn handle_global_var(
     target: &nac3parser::ast::Expr,
     value: Option<&nac3parser::ast::Expr>,
-    resolver: &(dyn nac3core::symbol_resolver::SymbolResolver + Send + Sync),
+    resolver: &Arc<dyn nac3core::symbol_resolver::SymbolResolver + Send + Sync>,
     internal_resolver: &ResolverInternal,
+    composer: &mut composer::TopLevelComposer,
 ) -> Result<(), String> {
     let nac3parser::ast::ExprKind::Name { id, .. } = target.node else {
         return Err(format!(
@@ -218,8 +221,18 @@ fn handle_global_var(
         ));
     };
 
-    if let Ok(val) = toplevel::helper::parse_parameter_default_value(value, resolver) {
+    if let Ok(val) = toplevel::helper::parse_parameter_default_value(value, &**resolver) {
         internal_resolver.add_module_global(id, val);
+        let (name, def_id, _) = composer
+            .register_top_level_var(
+                id,
+                None,
+                Some(resolver.clone()),
+                "__main__",
+                target.location,
+            )
+            .unwrap();
+        internal_resolver.add_id_def(name, def_id);
         Ok(())
     } else {
         Err(format!(
@@ -382,17 +395,12 @@ fn compile(code: &String, run_symbol: &String, output_filename: &Path) -> Result
     for mut stmt in parser_result {
         match stmt.node {
             nac3parser::ast::StmtKind::Assign { targets, value, .. } => {
-                let def_list = composer.extract_def_list();
-                let unifier = &mut composer.unifier;
-                let primitives = &composer.primitives_ty;
                 handle_assignment_pattern(
                     &targets,
                     &value,
-                    resolver.as_ref(),
+                    resolver.clone(),
                     internal_resolver.as_ref(),
-                    &def_list,
-                    unifier,
-                    primitives,
+                    &mut composer,
                 )?;
             }
             nac3parser::ast::StmtKind::AnnAssign {
@@ -403,14 +411,10 @@ fn compile(code: &String, run_symbol: &String, output_filename: &Path) -> Result
                 handle_global_var(
                     &target,
                     value.as_ref().map(Box::as_ref),
-                    resolver.as_ref(),
+                    &resolver,
                     internal_resolver.as_ref(),
+                    &mut composer,
                 )?;
-
-                let (name, def_id, _) = composer
-                    .register_top_level(stmt, Some(resolver.clone()), "__main__", true)
-                    .unwrap();
-                internal_resolver.add_id_def(name, def_id);
             }
             _ => {
                 if let nac3parser::ast::StmtKind::FunctionDef { name, .. } = &mut stmt.node {