From 26da66d73f2bf5eb23f52d6817e98df806a61bb0 Mon Sep 17 00:00:00 2001
From: Folkert <folkert@folkertdev.nl>
Date: Fri, 13 Aug 2021 15:41:32 +0200
Subject: [PATCH] remove from_mutmap

---
 compiler/types/src/subs.rs  | 10 ++++++++++
 compiler/unify/src/unify.rs | 20 ++++++--------------
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/compiler/types/src/subs.rs b/compiler/types/src/subs.rs
index 174d4c69cf..f6c3ca682b 100644
--- a/compiler/types/src/subs.rs
+++ b/compiler/types/src/subs.rs
@@ -1498,6 +1498,16 @@ impl UnionTags {
         )
     }
 
+    pub fn tag_without_arguments(subs: &mut Subs, tag_name: TagName) -> Self {
+        subs.tag_names.push(tag_name);
+
+        Self {
+            length: 1,
+            tag_names_start: (subs.tag_names.len() - 1) as u32,
+            variables_start: 0,
+        }
+    }
+
     pub fn insert_slices_into_subs<I>(subs: &mut Subs, input: I) -> Self
     where
         I: IntoIterator<Item = (TagName, VariableSubsSlice)>,
diff --git a/compiler/unify/src/unify.rs b/compiler/unify/src/unify.rs
index a0bc958e93..fbfe69b6d3 100644
--- a/compiler/unify/src/unify.rs
+++ b/compiler/unify/src/unify.rs
@@ -1285,15 +1285,8 @@ fn unify_function_or_tag_union_and_func(
 ) -> Outcome {
     let tag_name = subs[*tag_name_index].clone();
 
-    let mut new_tags = MutMap::with_capacity_and_hasher(1, default_hasher());
-
-    new_tags.insert(
-        tag_name,
-        subs.get_subs_slice(*function_arguments.as_subs_slice())
-            .to_owned(),
-    );
-
-    let content = Content::Structure(from_mutmap(subs, new_tags, tag_ext));
+    let union_tags = UnionTags::insert_slices_into_subs(subs, [(tag_name, function_arguments)]);
+    let content = Content::Structure(FlatType::TagUnion(union_tags, tag_ext));
 
     let new_tag_union_var = fresh(subs, pool, ctx, content);
 
@@ -1304,12 +1297,11 @@ fn unify_function_or_tag_union_and_func(
     };
 
     {
+        let tag_name = TagName::Closure(tag_symbol);
+        let union_tags = UnionTags::tag_without_arguments(subs, tag_name);
+
         let lambda_set_ext = subs.fresh_unnamed_flex_var();
-
-        let mut closure_tags = MutMap::with_capacity_and_hasher(1, default_hasher());
-        closure_tags.insert(TagName::Closure(tag_symbol), vec![]);
-
-        let lambda_set_content = Structure(from_mutmap(subs, closure_tags, lambda_set_ext));
+        let lambda_set_content = Structure(FlatType::TagUnion(union_tags, lambda_set_ext));
 
         let tag_lambda_set = register(
             subs,