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-rw-r--r--src/Propellor/Types/Info.hs10
1 files changed, 7 insertions, 3 deletions
diff --git a/src/Propellor/Types/Info.hs b/src/Propellor/Types/Info.hs
index 06c45ed2..2ab6da7b 100644
--- a/src/Propellor/Types/Info.hs
+++ b/src/Propellor/Types/Info.hs
@@ -17,6 +17,7 @@ module Propellor.Types.Info (
import Data.Dynamic
import Data.Maybe
import Data.Monoid
+import qualified Data.Semigroup as Sem
import qualified Data.Typeable as T
import Prelude
@@ -25,7 +26,7 @@ import Prelude
-- Many different types of data can be contained in the same Info value
-- at the same time. See `toInfo` and `fromInfo`.
newtype Info = Info [InfoEntry]
- deriving (Monoid, Show)
+ deriving (Sem.Semigroup, Monoid, Show)
data InfoEntry where
InfoEntry :: (IsInfo v, Typeable v) => v -> InfoEntry
@@ -80,10 +81,13 @@ mapInfo f (Info l) = Info (map go l)
data InfoVal v = NoInfoVal | InfoVal v
deriving (Typeable, Show)
+instance Sem.Semigroup (InfoVal v) where
+ _ <> v@(InfoVal _) = v
+ v <> NoInfoVal = v
+
instance Monoid (InfoVal v) where
mempty = NoInfoVal
- mappend _ v@(InfoVal _) = v
- mappend v NoInfoVal = v
+ mappend = (<>)
instance (Typeable v, Show v) => IsInfo (InfoVal v) where
propagateInfo _ = PropagateInfo False