Control.Validation.Class

Checkable

The Validatable typeclass.

Note: It is not inteded to be used for testing of internal integrity of types, i.e. it does not check if a Text has a valid internal representation. For testing internal integrity please use the package (validity)[https:/stackage.orgpackage/validity]. The typeclass is split up into three parts:

• checkChain: A list of checks that will be performed in that order. This has to be provided to give an instance. For the reason why it is given as a list and the checks are not combined via '(<>)', see the point for isValid.
• defaulCheck: A check performing all checks of checkChain

defaultCheck = fold checkChain

• isValid: A function determining whether a value is valid. This functions stops checking after the first of the checks from checkChain fails .This function is the reason why we need the checkChain, as a Check constructed by '(<>)' goes through all operands, so `passed $ runCheck (shortCheck <> longCheck) unvalidatedInput` evalutes the argument with longCheck even if shortCheck failed. But if we define

instance Validatable e m T where
  checkChain = CheckChain [ shortCheck, longCheck ]

then `isValid unvalidatedInput` stops after shortCheck failed.

validate :: (Validatable e m a, Functor m) => Unvalidated a -> m (Either (Seq e) a)

validate' :: Validatable e Identity a => Unvalidated a -> Either (Seq e) a

These are the functions used to validate data. Return either a validated result or a sequence of all validation errors that occured.

newtype CheckChain (e :: Type) (m :: Type -> Type) (a :: Type)

Constructors

CheckChain

Fields

• runCheckChain :: [Check e m a]

Instances

MFunctor (CheckChain e :: (Type -> Type) -> Type -> Type)

Defined in Control.Validation.Class

Methods

hoist :: Monad m => (forall a. m a -> n a) -> CheckChain e m b -> CheckChain e n b

Contravariant (CheckChain e m)

Defined in Control.Validation.Class

Methods

contramap :: (a -> b) -> CheckChain e m b -> CheckChain e m a

(>$) :: b -> CheckChain e m b -> CheckChain e m a

Applicative m => Divisible (CheckChain e m)

Defined in Control.Validation.Class

Methods

divide :: (a -> (b, c)) -> CheckChain e m b -> CheckChain e m c -> CheckChain e m a

conquer :: CheckChain e m a

Applicative m => Decidable (CheckChain e m)

Defined in Control.Validation.Class

Methods

lose :: (a -> Void) -> CheckChain e m a

choose :: (a -> Either b c) -> CheckChain e m b -> CheckChain e m c -> CheckChain e m a

Semigroup (CheckChain e m a)

Defined in Control.Validation.Class

Methods

(<>) :: CheckChain e m a -> CheckChain e m a -> CheckChain e m a

sconcat :: NonEmpty (CheckChain e m a) -> CheckChain e m a

stimes :: Integral b => b -> CheckChain e m a -> CheckChain e m a

Monoid (CheckChain e m a)

Defined in Control.Validation.Class

Methods

mempty :: CheckChain e m a

mappend :: CheckChain e m a -> CheckChain e m a -> CheckChain e m a

mconcat :: [CheckChain e m a] -> CheckChain e m a

overChain :: (Check e m a -> Check e' n b) -> CheckChain e m a -> CheckChain e' n b

(+?+) :: CheckChain e m a -> CheckChain e m a -> CheckChain e m a infixr 5

Convenience synonym.

singleChain :: Check e m a -> CheckChain e m a

Constructs a chain with only one check.

class Validatable (e :: Type) (m :: Type -> Type) (a :: Type) | a -> m, a -> e where

Minimal complete definition

Nothing

Methods

checkChain :: CheckChain e m a

checkChain :: (Generic a, GValidatable e m (Rep a)) => CheckChain e m a

defaultCheck :: Check e m a

defaultCheck :: Applicative m => Check e m a

isValid :: Unvalidated a -> m Bool

isValid :: Applicative m => Unvalidated a -> m Bool

Instances

Validatable Void Identity Bool

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Bool

defaultCheck :: Check Void Identity Bool

isValid :: Unvalidated Bool -> Identity Bool

Validatable Void Identity Char

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Char

defaultCheck :: Check Void Identity Char

isValid :: Unvalidated Char -> Identity Bool

Validatable Void Identity Double

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Double

defaultCheck :: Check Void Identity Double

isValid :: Unvalidated Double -> Identity Bool

Validatable Void Identity Float

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Float

defaultCheck :: Check Void Identity Float

isValid :: Unvalidated Float -> Identity Bool

Validatable Void Identity Int

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Int

defaultCheck :: Check Void Identity Int

isValid :: Unvalidated Int -> Identity Bool

Validatable Void Identity Int8

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Int8

defaultCheck :: Check Void Identity Int8

isValid :: Unvalidated Int8 -> Identity Bool

Validatable Void Identity Int16

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Int16

defaultCheck :: Check Void Identity Int16

isValid :: Unvalidated Int16 -> Identity Bool

Validatable Void Identity Int32

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Int32

defaultCheck :: Check Void Identity Int32

isValid :: Unvalidated Int32 -> Identity Bool

Validatable Void Identity Int64

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Int64

defaultCheck :: Check Void Identity Int64

isValid :: Unvalidated Int64 -> Identity Bool

Validatable Void Identity Integer

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Integer

defaultCheck :: Check Void Identity Integer

isValid :: Unvalidated Integer -> Identity Bool

Validatable Void Identity ()

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity ()

defaultCheck :: Check Void Identity ()

isValid :: Unvalidated () -> Identity Bool

Validatable Void Identity ByteString

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity ByteString

defaultCheck :: Check Void Identity ByteString

isValid :: Unvalidated ByteString -> Identity Bool

Validatable Void Identity Text

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity Text

defaultCheck :: Check Void Identity Text

isValid :: Unvalidated Text -> Identity Bool

(Validatable e m a, Applicative m) => Validatable e m [a]

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain e m [a]

defaultCheck :: Check e m [a]

isValid :: Unvalidated [a] -> m Bool

(Validatable e m a, Applicative m) => Validatable e m (Maybe a)

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain e m (Maybe a)

defaultCheck :: Check e m (Maybe a)

isValid :: Unvalidated (Maybe a) -> m Bool

Validatable Void Identity (TrivialCheck a)

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity (TrivialCheck a)

defaultCheck :: Check Void Identity (TrivialCheck a)

isValid :: Unvalidated (TrivialCheck a) -> Identity Bool

(Validatable e m b, Validatable e m a, Applicative m) => Validatable e m (Either a b)

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain e m (Either a b)

defaultCheck :: Check e m (Either a b)

isValid :: Unvalidated (Either a b) -> m Bool

newtype TrivialCheck a

Constructors

TrivialCheck

Fields

• unTrivialCheck :: a

Instances

Validatable Void Identity (TrivialCheck a)

Defined in Control.Validation.Class

Methods

checkChain :: CheckChain Void Identity (TrivialCheck a)

defaultCheck :: Check Void Identity (TrivialCheck a)

isValid :: Unvalidated (TrivialCheck a) -> Identity Bool

Helper for deriving Validatable

Helper for deriving Validatable

Intended for use with `-XDerivingVia` like

data X = X Int
    deriving (Validatable Void Identity) via (TrivialCheck X)
-- or with `-XStandaloneDeriving`
data Y = Y String
deriving via (TrivialCheck Y) instance (Validatable Void Identity Y) 

Reexports