From 14fe4c4d6b5a29be94ecfc0572e0f9a9a081e795 Mon Sep 17 00:00:00 2001 From: Joey Hess Date: Mon, 30 Apr 2018 09:03:46 -0400 Subject: fix broken SemigroupMonoid transition <> Turns out that with ghc 8.2.2, the instructions given on the page don't work. And the cppless variant that I had compiles, but into effectively mappend = mappend so it loops. The only way I can see to make it work without cpp is to use mappend = (Sem.<>) which is ugly and a land mine waiting to explode if someone changes it to a nicer mappend = (<>) with a newer version of ghc which will compile it and work ok, while breaking it with 8.2.2. Sigh. I posted to haskell-cafe about this. --- src/Propellor/Types/Info.hs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/Propellor/Types/Info.hs') diff --git a/src/Propellor/Types/Info.hs b/src/Propellor/Types/Info.hs index 2ab6da7b..b941cc8f 100644 --- a/src/Propellor/Types/Info.hs +++ b/src/Propellor/Types/Info.hs @@ -87,7 +87,7 @@ instance Sem.Semigroup (InfoVal v) where instance Monoid (InfoVal v) where mempty = NoInfoVal - mappend = (<>) + mappend = (Sem.<>) instance (Typeable v, Show v) => IsInfo (InfoVal v) where propagateInfo _ = PropagateInfo False -- cgit v1.2.3