From aaf43bda5c50a9d63979db8cb103dd2238c9b658 Mon Sep 17 00:00:00 2001
From: Chris Penner <christopher.penner@gmail.com>
Date: Wed, 16 Oct 2024 17:29:00 -0700
Subject: [PATCH] Fiddling with ref'write conventions

---
 unison-runtime/src/Unison/Runtime/Builtin.hs | 4 +---
 unison-runtime/src/Unison/Runtime/Foreign.hs | 3 ---
 unison-runtime/src/Unison/Runtime/Stack.hs   | 4 ++++
 3 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/unison-runtime/src/Unison/Runtime/Builtin.hs b/unison-runtime/src/Unison/Runtime/Builtin.hs
index 03c35acc7d..ee4ee34ad3 100644
--- a/unison-runtime/src/Unison/Runtime/Builtin.hs
+++ b/unison-runtime/src/Unison/Runtime/Builtin.hs
@@ -1095,9 +1095,7 @@ ref'read =
 
 ref'write :: SuperNormal Symbol
 ref'write =
-  binop0 1 $ \[ref, val, unit] ->
-    TLetD unit BX (TCon Ty.unitRef 0 [])
-    $ (TPrm WREF [ref, val])
+  binop0 0 $ \[ref, val] -> (TPrm WREF [ref, val])
 
 seek'handle :: ForeignOp
 seek'handle instr =
diff --git a/unison-runtime/src/Unison/Runtime/Foreign.hs b/unison-runtime/src/Unison/Runtime/Foreign.hs
index d4a8853b48..26e5911d1f 100644
--- a/unison-runtime/src/Unison/Runtime/Foreign.hs
+++ b/unison-runtime/src/Unison/Runtime/Foreign.hs
@@ -261,9 +261,6 @@ instance BuiltinForeign Value where foreignRef = Tagged Ty.valueRef
 
 instance BuiltinForeign TimeSpec where foreignRef = Tagged Ty.timeSpecRef
 
--- TODO: investigate this
-instance BuiltinForeign (IORef closure) where foreignRef = Tagged Ty.refRef
-
 data HashAlgorithm where
   -- Reference is a reference to the hash algorithm
   HashAlgorithm :: (Hash.HashAlgorithm a) => Reference -> a -> HashAlgorithm
diff --git a/unison-runtime/src/Unison/Runtime/Stack.hs b/unison-runtime/src/Unison/Runtime/Stack.hs
index 16ba3be3fb..759e732000 100644
--- a/unison-runtime/src/Unison/Runtime/Stack.hs
+++ b/unison-runtime/src/Unison/Runtime/Stack.hs
@@ -96,6 +96,8 @@ module Unison.Runtime.Stack
 where
 
 import Control.Monad.Primitive
+import Data.IORef (IORef)
+import Data.Tagged (Tagged (..))
 import Data.Word
 import GHC.Exts as L (IsList (..))
 import Unison.Prelude
@@ -159,6 +161,8 @@ instance Ord K where
 newtype Closure = Closure {unClosure :: (GClosure (RComb Closure))}
   deriving stock (Show, Eq, Ord)
 
+instance BuiltinForeign (IORef Closure) where foreignRef = Tagged Ty.refRef
+
 type IxClosure = GClosure CombIx
 
 data GClosure comb