From 49476d06e1eeba59ffbf025af134d600ca317827 Mon Sep 17 00:00:00 2001
From: ychenfo <yc@m-labs.hk>
Date: Mon, 22 Nov 2021 15:06:16 +0800
Subject: [PATCH] nac3core: clearer comments

---
 nac3core/src/codegen/concrete_type.rs | 5 +++--
 nac3core/src/typecheck/typedef/mod.rs | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/nac3core/src/codegen/concrete_type.rs b/nac3core/src/codegen/concrete_type.rs
index 422e4df..140142e 100644
--- a/nac3core/src/codegen/concrete_type.rs
+++ b/nac3core/src/codegen/concrete_type.rs
@@ -148,8 +148,9 @@ impl ConcreteTypeStore {
                         .borrow()
                         .iter()
                         .filter_map(|(name, ty)| {
-                            // filter out functions as they can have type vars and
-                            // will not affect codegen
+                            // here we should not have type vars, but some partial instantiated
+                            // class methods can still have uninstantiated type vars, so
+                            // filter out all the methods, as this will not affect codegen
                             if let TypeEnum::TFunc( .. ) = &*unifier.get_ty(ty.0) {
                                 None
                             } else {
diff --git a/nac3core/src/typecheck/typedef/mod.rs b/nac3core/src/typecheck/typedef/mod.rs
index 85e619c..0d194b2 100644
--- a/nac3core/src/typecheck/typedef/mod.rs
+++ b/nac3core/src/typecheck/typedef/mod.rs
@@ -725,8 +725,9 @@ impl Unifier {
             if let TypeEnum::TVar { id, range, .. } =
                 self.unification_table.probe_value(*v).as_ref()
             {
-                // need to do this for partial instantiated function
-                // (in class methods that contains type vars not in class)
+                // for class methods that contain type vars not in class declaration,
+                // as long as there exits one uninstantiated type var, the function is not instantiated,
+                // and need to do substitution on those type vars
                 if k == id {
                     instantiated = false;
                     vars.push((*k, range.clone()));