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{- proposed and accepted values
-
- Copyright 2020 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module Types.ProposedAccepted where
import Test.QuickCheck
-- | A value that may be proposed, or accepted.
--
-- When parsing/validating the value, may want to error out on invalid
-- input. But if a previous version of git-annex accepted an invalid value,
-- it's too late to error out, and instead the bad value may be ignored.
data ProposedAccepted t = Proposed t | Accepted t
deriving (Show)
fromProposedAccepted :: ProposedAccepted t -> t
fromProposedAccepted (Proposed t) = t
fromProposedAccepted (Accepted t) = t
-- | Whether a value is proposed or accepted does not matter when checking
-- equality.
instance Eq t => Eq (ProposedAccepted t) where
a == b = fromProposedAccepted a == fromProposedAccepted b
-- | Order by the contained value, not by whether it's proposed or
-- accepted.
instance Ord t => Ord (ProposedAccepted t) where
compare a b = compare (fromProposedAccepted a) (fromProposedAccepted b)
instance Arbitrary t => Arbitrary (ProposedAccepted t) where
arbitrary = oneof
[ Proposed <$> arbitrary
, Accepted <$> arbitrary
]
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