From fe80b31555c27f038b20eb84eb1e747781d7c76b Mon Sep 17 00:00:00 2001
From: Tom Smeding <tom@tomsmeding.com>
Date: Wed, 18 Jun 2025 10:11:12 +0200
Subject: Don't destroy effects in sparse plus

---
 src/CHAD.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'src/CHAD.hs')

diff --git a/src/CHAD.hs b/src/CHAD.hs
index 3399de2..9a08457 100644
--- a/src/CHAD.hs
+++ b/src/CHAD.hs
@@ -404,7 +404,8 @@ subenvPlus :: SBool req1 -> SBool req2
                          -> (forall e. Ex e (Tup env1) -> Ex e (Tup env2) -> Ex e (Tup env3))
                          -> r)
            -> r
-subenvPlus _ _ SNil SETop SETop k = k SETop (Inj id) (Inj id) (\_ _ -> ENil ext)
+-- don't destroy effects!
+subenvPlus _ _ SNil SETop SETop k = k SETop (Inj id) (Inj id) (\a b -> use a $ use b $ ENil ext)
 
 subenvPlus req1 req2 (SCons _ env) (SENo sub1) (SENo sub2) k =
   subenvPlus req1 req2 env sub1 sub2 $ \sub3 s31 s32 pl ->
-- 
cgit v1.2.3-70-g09d2