Safe Haskell	None
Language	Haskell2010

Data.Functor.Field

Description

Provides Generic1 derivation of Representable based on Field.

This relies on the observation that a parametric function forall a. f a -> a is isomorphic to the set of "indices" of f, i.e. Rep f. With the appropriate instances, we can do anything with it that we could with a hand-written ADT Rep type. So, this module provides a way to use exactly that type as Rep, and the needed instances to make it convenient to use.

Synopsis

newtype Field f = Field {
- getField :: forall a. f a -> a
}
newtype FieldRep f a = FieldRep (f a)
class FieldPaths f where
- fieldPaths :: f [PathComponent]
class GFieldPaths rec where
- gfieldPaths :: ([PathComponent] -> r) -> rec r
class GTabulate rec where
- gtabulate :: (Field rec -> r) -> rec r

Documentation

newtype Field f Source #

A Rep type in the form of a parametric accessor function.

Constructors

Field
Fields getField :: forall a. f a -> a

Instances

Instances details

(Traversable f, Applicative f) => Eq (Field f) Source #
Instance details Defined in Data.Functor.Field Methods (==) :: Field f -> Field f -> Bool # (/=) :: Field f -> Field f -> Bool #
(Traversable f, Applicative f) => Ord (Field f) Source #
Instance details Defined in Data.Functor.Field Methods compare :: Field f -> Field f -> Ordering # (<) :: Field f -> Field f -> Bool # (<=) :: Field f -> Field f -> Bool # (>) :: Field f -> Field f -> Bool # (>=) :: Field f -> Field f -> Bool # max :: Field f -> Field f -> Field f # min :: Field f -> Field f -> Field f #
FieldPaths f => Show (Field f) Source #
Instance details Defined in Data.Functor.Field Methods showsPrec :: Int -> Field f -> ShowS # show :: Field f -> String # showList :: [Field f] -> ShowS #
(Traversable f, Applicative f) => Hashable (Field f) Source #
Instance details Defined in Data.Functor.Field Methods hashWithSalt :: Int -> Field f -> Int # hash :: Field f -> Int #
FieldPaths f => Portray (Field f) Source #
Instance details Defined in Data.Functor.Field Methods portray :: Field f -> Portrayal # portrayList :: [Field f] -> Portrayal #
(Traversable f, Applicative f, FieldPaths f) => Diff (Field f) Source #
Instance details Defined in Data.Functor.Field Methods diff :: Field f -> Field f -> Maybe Portrayal #

newtype FieldRep f a Source #

A newtype carrying instances for use with DerivingVia.

This provides Applicative, Monad, Representable, and Update.

Constructors

FieldRep (f a)

Instances

Instances details

(Generic1 f, GTabulate (Rep1 f), Functor f) => Monad (FieldRep f) Source #
Instance details Defined in Data.Functor.Field Methods (>>=) :: FieldRep f a -> (a -> FieldRep f b) -> FieldRep f b # (>>) :: FieldRep f a -> FieldRep f b -> FieldRep f b # return :: a -> FieldRep f a #
Functor f => Functor (FieldRep f) Source #
Instance details Defined in Data.Functor.Field Methods fmap :: (a -> b) -> FieldRep f a -> FieldRep f b # (<$) :: a -> FieldRep f b -> FieldRep f a #
(Generic1 f, GTabulate (Rep1 f), Functor f) => Applicative (FieldRep f) Source #
Instance details Defined in Data.Functor.Field Methods pure :: a -> FieldRep f a # (<>) :: FieldRep f (a -> b) -> FieldRep f a -> FieldRep f b # liftA2 :: (a -> b -> c) -> FieldRep f a -> FieldRep f b -> FieldRep f c # (>) :: FieldRep f a -> FieldRep f b -> FieldRep f b # (<*) :: FieldRep f a -> FieldRep f b -> FieldRep f a #
(Generic1 f, GTabulate (Rep1 f), Functor f) => Distributive (FieldRep f) Source #
Instance details Defined in Data.Functor.Field Methods distribute :: Functor f0 => f0 (FieldRep f a) -> FieldRep f (f0 a) # collect :: Functor f0 => (a -> FieldRep f b) -> f0 a -> FieldRep f (f0 b) # distributeM :: Monad m => m (FieldRep f a) -> FieldRep f (m a) # collectM :: Monad m => (a -> FieldRep f b) -> m a -> FieldRep f (m b) #
(Generic1 f, GTabulate (Rep1 f), Functor f) => Representable (FieldRep f) Source #
Instance details Defined in Data.Functor.Field Associated Types type Rep (FieldRep f) # Methods tabulate :: (Rep (FieldRep f) -> a) -> FieldRep f a # index :: FieldRep f a -> Rep (FieldRep f) -> a #
(Generic1 f, GTabulate (Rep1 f), GUpdate (Rep1 f), Functor f) => Update (FieldRep f) Source #
Instance details Defined in Data.Functor.Update Methods overRep :: Rep (FieldRep f) -> (a -> a) -> FieldRep f a -> FieldRep f a Source #
type Rep (FieldRep f) Source #
Instance details Defined in Data.Functor.Field type Rep (FieldRep f) = Field f

class FieldPaths f where Source #

Build a record where each field has a description of the field's location.

This primarily powers the Show and Portray instances of Field.

Methods

fieldPaths :: f [PathComponent] Source #

Instances

Instances details

(Generic1 rec, GFieldPaths (Rep1 rec)) => FieldPaths (Wrapped1 (Generic1 :: (Type -> Type) -> Constraint) rec) Source #
Instance details Defined in Data.Functor.Field Methods fieldPaths :: Wrapped1 Generic1 rec [PathComponent] Source #

class GFieldPaths rec where Source #

The Generic1 implementation of FieldPaths.

As with GTabulate, derive this only to enable using your type as a sub-record; otherwise just derive FieldPaths directly.

Methods

gfieldPaths :: ([PathComponent] -> r) -> rec r Source #

Instances

Instances details

GFieldPaths Par1 Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> Par1 r Source #
GFieldPaths (U1 :: Type -> Type) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> U1 r Source #
GFieldPaths rec => GFieldPaths (Rec1 rec) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> Rec1 rec r Source #
(GFieldPaths f, GFieldPaths g) => GFieldPaths (f :*: g) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> (f :*: g) r Source #
GFieldPaths rec => GFieldPaths (M1 D ('MetaData n m p 'True) (M1 C i (M1 S j rec))) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> M1 D ('MetaData n m p 'True) (M1 C i (M1 S j rec)) r Source #
GFieldPaths rec => GFieldPaths (M1 D ('MetaData n m p 'False) rec) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> M1 D ('MetaData n m p 'False) rec r Source #
GFieldPaths rec => GFieldPaths (M1 C i rec) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> M1 C i rec r Source #
(KnownSymbol sym, GFieldPaths rec) => GFieldPaths (M1 S ('MetaSel ('Just sym) b c d) rec) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> M1 S ('MetaSel ('Just sym) b c d) rec r Source #
(GFieldPaths f, GFieldPaths g) => GFieldPaths (f :.: g) Source #
Instance details Defined in Data.Functor.Field Methods gfieldPaths :: ([PathComponent] -> r) -> (f :.: g) r Source #

class GTabulate rec where Source #

The Generic1 implementation of tabulate for Field.

Methods

gtabulate :: (Field rec -> r) -> rec r Source #

Instances

Instances details

GTabulate Par1 Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field Par1 -> r) -> Par1 r Source #
GTabulate (U1 :: Type -> Type) Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field U1 -> r) -> U1 r Source #
GTabulate rec => GTabulate (Rec1 rec) Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field (Rec1 rec) -> r) -> Rec1 rec r Source #
(GTabulate f, GTabulate g) => GTabulate (f :*: g) Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field (f :: g) -> r) -> (f :: g) r Source #
GTabulate rec => GTabulate (M1 k i rec) Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field (M1 k i rec) -> r) -> M1 k i rec r Source #
(GTabulate f, GTabulate g) => GTabulate (f :.: g) Source #
Instance details Defined in Data.Functor.Field Methods gtabulate :: (Field (f :.: g) -> r) -> (f :.: g) r Source #