From 6dd52ac18236f75853920096154aff987be47db2 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Thu, 10 Oct 2019 17:59:44 -0700
Subject: [PATCH] Fix bug from small improvements

---
 04/ast.cpp | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/04/ast.cpp b/04/ast.cpp
index f8a88df..8880df2 100644
--- a/04/ast.cpp
+++ b/04/ast.cpp
@@ -97,10 +97,6 @@ type_ptr ast_case::typecheck(type_mgr& mgr, const type_env& env) const {
     type_ptr case_type = mgr.resolve(of->typecheck(mgr, env), var);
     type_ptr branch_type = mgr.new_type();
 
-    if(!dynamic_cast<type_base*>(case_type.get())) {
-        throw type_error("attempting case analysis of non-data type");
-    }
-
     for(auto& branch : branches) {
         type_env new_env = env.scope();
         branch->pat->match(case_type, mgr, new_env);
@@ -108,6 +104,11 @@ type_ptr ast_case::typecheck(type_mgr& mgr, const type_env& env) const {
         mgr.unify(branch_type, curr_branch_type);
     }
 
+    case_type = mgr.resolve(case_type, var);
+    if(!dynamic_cast<type_base*>(case_type.get())) {
+        throw type_error("attempting case analysis of non-data type");
+    }
+
     return branch_type;
 }