{-# LANGUAGE DataKinds #-}
{-# LANGUAGE KindSignatures #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UndecidableInstances #-}
module Propellor.EnsureProperty
( ensureProperty
, property'
, OuterMetaTypesWitness
, EnsurePropertyAllowed
) where
import Propellor.Types
import Propellor.Types.Core
import Propellor.Types.MetaTypes
import Propellor.Exception
import GHC.TypeLits
import GHC.Exts (Constraint)
import Data.Type.Bool
import Data.Monoid
import Prelude
ensureProperty
::
( EnsurePropertyAllowed inner outer)
=> OuterMetaTypesWitness outer
-> Property (MetaTypes inner)
-> Propellor Result
ensureProperty _ = maybe (return NoChange) catchPropellor . getSatisfy
type family EnsurePropertyAllowed inner outer :: Constraint where
EnsurePropertyAllowed inner outer = 'True ~
((EnsurePropertyNoInfo inner)
&&
(EnsurePropertyTargetOSMatches inner outer))
type family EnsurePropertyNoInfo (l :: [a]) :: Bool where
EnsurePropertyNoInfo '[] = 'True
EnsurePropertyNoInfo (t ': ts) = If (Not (t `EqT` 'WithInfo))
(EnsurePropertyNoInfo ts)
(TypeError ('Text "Cannot use ensureProperty with a Property that HasInfo."))
type family EnsurePropertyTargetOSMatches inner outer where
EnsurePropertyTargetOSMatches inner outer =
If (Targets outer `IsSubset` Targets inner)
'True
(IfStuck (Targets outer)
(DelayError
('Text "ensureProperty outer Property type is not able to be inferred here."
':$$: 'Text "Consider adding a type annotation."
)
)
(DelayErrorFcf
('Text "ensureProperty inner Property is missing support for: "
':$$: PrettyPrintMetaTypes (Difference (Targets outer) (Targets inner))
)
)
)
property'
:: SingI metatypes
=> Desc
-> (OuterMetaTypesWitness metatypes -> Propellor Result)
-> Property (MetaTypes metatypes)
property' d a =
let p = Property sing d (Just (a (outerMetaTypesWitness p))) mempty mempty
in p
newtype OuterMetaTypesWitness metatypes = OuterMetaTypesWitness (MetaTypes metatypes)
outerMetaTypesWitness :: Property (MetaTypes l) -> OuterMetaTypesWitness l
outerMetaTypesWitness (Property metatypes _ _ _ _) = OuterMetaTypesWitness metatypes