Safe Haskell	None
Language	Haskell2010

Opaleye.Internal.MaybeFields

Contents

Orphan instances

Synopsis

data MaybeFields fields = MaybeFields {
- mfPresent :: Column SqlBool
- mfFields :: fields
}
nothingFields :: Default Nullspec a a => MaybeFields a
nothingFieldsOfTypeOf :: a -> MaybeFields a
justFields :: a -> MaybeFields a
maybeFields :: Default IfPP b b => b -> (a -> b) -> MaybeFields a -> b
fromMaybeFields :: Default IfPP b b => b -> MaybeFields b -> b
maybeFieldsToSelect :: SelectArr (MaybeFields a) a
catMaybeFields :: SelectArr i (MaybeFields a) -> SelectArr i a
maybeFieldsExplicit :: IfPP b b' -> b -> (a -> b) -> MaybeFields a -> b'
fromMaybeFieldsExplicit :: IfPP b b -> b -> MaybeFields b -> b
nothingFieldsExplicit :: Nullspec a b -> MaybeFields b
traverseMaybeFields :: SelectArr a b -> SelectArr (MaybeFields a) (MaybeFields b)
optional :: SelectArr i a -> SelectArr i (MaybeFields a)
optionalInternal :: (Field (Nullable SqlBool) -> a -> r) -> Select a -> Select r
lateralLeftJoinOptional :: SelectArr i a -> SelectArr i b -> ((a, b) -> Field SqlBool) -> SelectArr i (a, MaybeFields b)
optionalRestrictOptional :: Select a -> SelectArr (a -> Field SqlBool) (MaybeFields a)
fromFieldsMaybeFields :: FromFields fields haskells -> FromFields (MaybeFields fields) (Maybe haskells)
productProfunctorMaybeFields :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> p a b -> p (MaybeFields a) (MaybeFields b)
nullspecMaybeFields :: Nullspec a b -> Nullspec (MaybeFields a) (MaybeFields b)
unpackspecMaybeFields :: Unpackspec a b -> Unpackspec (MaybeFields a) (MaybeFields b)
valuesspecMaybeFields :: Valuesspec a b -> Valuesspec (MaybeFields a) (MaybeFields b)
toFieldsMaybeFields :: Nullspec a b -> ToFields a b -> ToFields (Maybe a) (MaybeFields b)
ifPPMaybeFields :: IfPP a b -> IfPP (MaybeFields a) (MaybeFields b)
eqPPMaybeFields :: EqPP a b -> EqPP (MaybeFields a) (MaybeFields b)
unWithNulls :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> WithNulls p a b -> p (MaybeFields a) (MaybeFields b)
newtype WithNulls p a b = WithNulls (p (MaybeFields a) b)
mapMaybeFieldsWithNulls :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> WithNulls p a b -> WithNulls p (MaybeFields a) (MaybeFields b)
withNullsField :: (IsSqlType a, Profunctor p) => p (Column a) (Column a) -> WithNulls p (Column a) (Column a)
binaryspecMaybeFields :: WithNulls Binaryspec a b -> Binaryspec (MaybeFields a) (MaybeFields b)

Documentation

data MaybeFields fields Source #

The Opaleye analogue of Maybe

Constructors

MaybeFields
Fields mfPresent :: Column SqlBool mfFields :: fields

Instances

Instances details

Monad MaybeFields Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods (>>=) :: MaybeFields a -> (a -> MaybeFields b) -> MaybeFields b # (>>) :: MaybeFields a -> MaybeFields b -> MaybeFields b # return :: a -> MaybeFields a #
Functor MaybeFields Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods fmap :: (a -> b) -> MaybeFields a -> MaybeFields b # (<$) :: a -> MaybeFields b -> MaybeFields a #
Applicative MaybeFields Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods pure :: a -> MaybeFields a # (<>) :: MaybeFields (a -> b) -> MaybeFields a -> MaybeFields b # liftA2 :: (a -> b -> c) -> MaybeFields a -> MaybeFields b -> MaybeFields c # (>) :: MaybeFields a -> MaybeFields b -> MaybeFields b # (<*) :: MaybeFields a -> MaybeFields b -> MaybeFields a #
Default Unpackspec a b => Default Unpackspec (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: Unpackspec (MaybeFields a) (MaybeFields b) #
Default (WithNulls Binaryspec) a b => Default Binaryspec (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: Binaryspec (MaybeFields a) (MaybeFields b) #
Default IfPP a b => Default IfPP (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: IfPP (MaybeFields a) (MaybeFields b) #
Default EqPP a b => Default EqPP (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: EqPP (MaybeFields a) (MaybeFields b) #
Default FromFields fields haskells => Default FromFields (MaybeFields fields) (Maybe haskells) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: FromFields (MaybeFields fields) (Maybe haskells) #
Default Valuesspec a b => Default Valuesspec (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: Valuesspec (MaybeFields a) (MaybeFields b) #
(Default ToFields a b, Default Nullspec a b) => Default ToFields (Maybe a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: ToFields (Maybe a) (MaybeFields b) #
Default (WithNulls Distinctspec) a b => Default Distinctspec (MaybeFields a) (MaybeFields b) Source #
Instance details Defined in Opaleye.Internal.Distinct Methods def :: Distinctspec (MaybeFields a) (MaybeFields b) #
(Default (Inferrable FromFields) fields haskells, Maybe haskells ~ maybe_haskells) => Default (Inferrable FromFields) (MaybeFields fields) maybe_haskells Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: Inferrable FromFields (MaybeFields fields) maybe_haskells #

nothingFields :: Default Nullspec a a => MaybeFields a Source #

The Opaleye analogue of Nothing.

nothingFieldsOfTypeOf :: a -> MaybeFields a Source #

The Opaleye analogue of const Nothing. Can be useful to avoid type inference problems, because it doesn't pick up a type class constraint.

justFields :: a -> MaybeFields a Source #

The Opaleye analogue of Just. Equivalent to pure.

maybeFields :: Default IfPP b b => b -> (a -> b) -> MaybeFields a -> b Source #

The Opaleye analogue of maybe

fromMaybeFields :: Default IfPP b b => b -> MaybeFields b -> b Source #

The Opaleye analogue of fromMaybe

maybeFieldsToSelect :: SelectArr (MaybeFields a) a Source #

The Opaleye analogue of maybeToList

catMaybeFields :: SelectArr i (MaybeFields a) -> SelectArr i a Source #

The Opaleye analogue of catMaybes

maybeFieldsExplicit :: IfPP b b' -> b -> (a -> b) -> MaybeFields a -> b' Source #

fromMaybeFieldsExplicit :: IfPP b b -> b -> MaybeFields b -> b Source #

nothingFieldsExplicit :: Nullspec a b -> MaybeFields b Source #

traverseMaybeFields :: SelectArr a b -> SelectArr (MaybeFields a) (MaybeFields b) Source #

optional :: SelectArr i a -> SelectArr i (MaybeFields a) Source #

optionalInternal :: (Field (Nullable SqlBool) -> a -> r) -> Select a -> Select r Source #

lateralLeftJoinOptional :: SelectArr i a -> SelectArr i b -> ((a, b) -> Field SqlBool) -> SelectArr i (a, MaybeFields b) Source #

An example to demonstrate how the functionality of (lateral) LEFT JOIN can be recovered using optional.

optionalRestrictOptional :: Select a -> SelectArr (a -> Field SqlBool) (MaybeFields a) Source #

An example to demonstrate how the functionality of optionalRestrict can be recovered using optional.

fromFieldsMaybeFields :: FromFields fields haskells -> FromFields (MaybeFields fields) (Maybe haskells) Source #

productProfunctorMaybeFields :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> p a b -> p (MaybeFields a) (MaybeFields b) Source #

This is not safe in general because it relies on p not doing anything observable with the as if mfPresent is false. In particular, it won't work for Distinctspec because it does indeed look at the mfFields to check distinctness.

nullspecMaybeFields :: Nullspec a b -> Nullspec (MaybeFields a) (MaybeFields b) Source #

unpackspecMaybeFields :: Unpackspec a b -> Unpackspec (MaybeFields a) (MaybeFields b) Source #

valuesspecMaybeFields :: Valuesspec a b -> Valuesspec (MaybeFields a) (MaybeFields b) Source #

toFieldsMaybeFields :: Nullspec a b -> ToFields a b -> ToFields (Maybe a) (MaybeFields b) Source #

ifPPMaybeFields :: IfPP a b -> IfPP (MaybeFields a) (MaybeFields b) Source #

eqPPMaybeFields :: EqPP a b -> EqPP (MaybeFields a) (MaybeFields b) Source #

unWithNulls :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> WithNulls p a b -> p (MaybeFields a) (MaybeFields b) Source #

This is only safe if d is OK with having nulls passed through it when they claim to be non-null.

newtype WithNulls p a b Source #

Constructors

WithNulls (p (MaybeFields a) b)

Instances

Instances details

Profunctor p => Profunctor (WithNulls p) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods dimap :: (a -> b) -> (c -> d) -> WithNulls p b c -> WithNulls p a d # lmap :: (a -> b) -> WithNulls p b c -> WithNulls p a c # rmap :: (b -> c) -> WithNulls p a b -> WithNulls p a c # (#.) :: forall a b c q. Coercible c b => q b c -> WithNulls p a b -> WithNulls p a c # (.#) :: forall a b c q. Coercible b a => WithNulls p b c -> q a b -> WithNulls p a c #
ProductProfunctor p => ProductProfunctor (WithNulls p) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods purePP :: b -> WithNulls p a b # (**) :: WithNulls p a (b -> c) -> WithNulls p a b -> WithNulls p a c # empty :: WithNulls p () () # (*!) :: WithNulls p a b -> WithNulls p a' b' -> WithNulls p (a, a') (b, b') #
SumProfunctor p => SumProfunctor (WithNulls p) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods (+++!) :: WithNulls p a b -> WithNulls p a' b' -> WithNulls p (Either a a') (Either b b') #
(Profunctor p, IsSqlType a, Default p (Column a) (Column a)) => Default (WithNulls p) (Column a) (Column a) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods def :: WithNulls p (Column a) (Column a) #
Profunctor p => Functor (WithNulls p a) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods fmap :: (a0 -> b) -> WithNulls p a a0 -> WithNulls p a b # (<$) :: a0 -> WithNulls p a b -> WithNulls p a a0 #
ProductProfunctor p => Applicative (WithNulls p a) Source #
Instance details Defined in Opaleye.Internal.MaybeFields Methods pure :: a0 -> WithNulls p a a0 # (<>) :: WithNulls p a (a0 -> b) -> WithNulls p a a0 -> WithNulls p a b # liftA2 :: (a0 -> b -> c) -> WithNulls p a a0 -> WithNulls p a b -> WithNulls p a c # (>) :: WithNulls p a a0 -> WithNulls p a b -> WithNulls p a b # (<*) :: WithNulls p a a0 -> WithNulls p a b -> WithNulls p a a0 #

mapMaybeFieldsWithNulls :: ProductProfunctor p => p (Field SqlBool) (Field SqlBool) -> WithNulls p a b -> WithNulls p (MaybeFields a) (MaybeFields b) Source #

This is only safe if d is OK with having nulls passed through it when they claim to be non-null.

withNullsField :: (IsSqlType a, Profunctor p) => p (Column a) (Column a) -> WithNulls p (Column a) (Column a) Source #

This is only safe if d is OK with having nulls passed through it when they claim to be non-null.

binaryspecMaybeFields :: WithNulls Binaryspec a b -> Binaryspec (MaybeFields a) (MaybeFields b) Source #

Orphan instances

(Default (Inferrable ToFields) a b, Default Nullspec a b, MaybeFields b ~ maybeFields_b) => Default (Inferrable ToFields) (Maybe a) maybeFields_b Source #
Instance details Methods def :: Inferrable ToFields (Maybe a) maybeFields_b #