From 4b4cea587f127e9c65bb0c226068411a184f706c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 14 Mar 2018 15:06:40 -0400
Subject: [PATCH] letrec returns the address.

---
 src/Control/Abstract/Addressable.hs | 4 ++--
 src/Control/Abstract/Value.hs       | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Control/Abstract/Addressable.hs b/src/Control/Abstract/Addressable.hs
index 68048ddbc..047ec4b26 100644
--- a/src/Control/Abstract/Addressable.hs
+++ b/src/Control/Abstract/Addressable.hs
@@ -56,12 +56,12 @@ letrec :: ( MonadAddressable (LocationFor value) value m
           )
        => Name
        -> m value
-       -> m value
+       -> m (value, Address (LocationFor value) value)
 letrec name body = do
   addr <- alloc name
   v <- localEnv (envInsert name addr) body
   assign addr v
-  pure v
+  pure (v, addr)
 
 
 -- Instances
diff --git a/src/Control/Abstract/Value.hs b/src/Control/Abstract/Value.hs
index 7bd0c91cc..df7d19d4e 100644
--- a/src/Control/Abstract/Value.hs
+++ b/src/Control/Abstract/Value.hs
@@ -118,7 +118,7 @@ loop :: ( MonadAddressable (LocationFor value) value m
         )
      => m value
      -> m value
-loop = letrec (name "loop")
+loop = fmap fst . letrec (name "loop")
 
 continue :: ( MonadAddressable (LocationFor value) value m
             , MonadEnvironment value m