From 752fd59c1803419f4919365504065d3688b0d1ab Mon Sep 17 00:00:00 2001
From: sof <unknown>
Date: Mon, 24 Nov 1997 21:06:11 +0000
Subject: [PATCH] [project @ 1997-11-24 21:06:11 by sof] Have conflictFM return
Maybe type rather than list
---
ghc/compiler/rename/RnEnv.lhs | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/ghc/compiler/rename/RnEnv.lhs b/ghc/compiler/rename/RnEnv.lhs
index 54033542256a..577b795df0f8 100644
--- a/ghc/compiler/rename/RnEnv.lhs
+++ b/ghc/compiler/rename/RnEnv.lhs
@@ -529,11 +529,11 @@ conflictsFM bad fm1 fm2
conflictFM :: Ord a
=> (b->b->Bool)
-> FiniteMap a b -> a -> b
- -> [(a,(b,b))]
+ -> Maybe (a,(b,b))
conflictFM bad fm key elt
= case lookupFM fm key of
- Just elt' | bad elt elt' -> [(key,(elt,elt'))]
- other -> []
+ Just elt' | bad elt elt' -> Just (key,(elt,elt'))
+ other -> Nothing
\end{code}
--
GitLab