From 1fe02408eba2a8ca1d2fe2149cf57c4ef3a0266e Mon Sep 17 00:00:00 2001 From: Xavier Dectot Date: Mon, 17 Mar 2025 15:34:16 +0100 Subject: [PATCH] ST is not an instance of MonadFail. Fixes #14 --- src/Data/UnionFind/ST.hs | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/src/Data/UnionFind/ST.hs b/src/Data/UnionFind/ST.hs index 80241ae..a8f83b2 100644 --- a/src/Data/UnionFind/ST.hs +++ b/src/Data/UnionFind/ST.hs @@ -130,8 +130,10 @@ union' p1 p2 update = do point2@(Pt link_ref2) <- repr p2 -- The precondition ensures that we don't create cyclic structures. when (point1 /= point2) $ do - Info info_ref1 <- readSTRef link_ref1 - Info info_ref2 <- readSTRef link_ref2 + ir1 <- readSTRef link_ref1 + ir2 <- readSTRef link_ref2 + let Info info_ref1 = ir1 + Info info_ref2 = ir2 MkInfo w1 d1 <- readSTRef info_ref1 -- d1 is discarded MkInfo w2 d2 <- readSTRef info_ref2 d2' <- update d1 d2 -- 2.48.1