Safe Haskell	None
Language	Haskell2010

Data.Vinyl.Derived

Contents

Specializations for working with an ARec of named fields.

Description

Commonly used Rec instantiations.

Synopsis

type (:::) a b = '(a, b)
type FieldRec = Rec ElField
type AFieldRec ts = ARec ElField ts
type HList = Rec Identity
type LazyHList = Rec Thunk
getField :: ElField '(s, t) -> t
getLabel :: forall s t. ElField '(s, t) -> String
fieldMap :: (a -> b) -> ElField '(s, a) -> ElField '(s, b)
traverseField :: (KnownSymbol s, Functor f) => (a -> b) -> f (ElField '(s, a)) -> ElField '(s, f b)
rfield :: Functor f => (a -> f b) -> ElField '(s, a) -> f (ElField '(s, b))
(=:) :: KnownSymbol l => Label (l :: Symbol) -> (v :: *) -> ElField (l ::: v)
rgetf :: forall l f v record us. (HasField record l us us v v, RecElemFCtx record f) => Label l -> record f us -> f (l ::: v)
rvalf :: (HasField record l us us v v, RecElemFCtx record ElField) => Label l -> record ElField us -> v
rputf' :: forall l v v' record us us'. (HasField record l us us' v v', KnownSymbol l, RecElemFCtx record ElField) => Label l -> v' -> record ElField us -> record ElField us'
rputf :: forall l v record us. (HasField record l us us v v, KnownSymbol l, RecElemFCtx record ElField) => Label l -> v -> record ElField us -> record ElField us
rlensfL' :: forall l v v' record g f us us'. (Functor g, HasField record l us us' v v', RecElemFCtx record f) => Label l -> (f (l ::: v) -> g (f (l ::: v'))) -> record f us -> g (record f us')
rlensfL :: forall l v record g f us. (Functor g, HasField record l us us v v, RecElemFCtx record f) => Label l -> (f (l ::: v) -> g (f (l ::: v))) -> record f us -> g (record f us)
rlensf' :: forall l v v' record g us us'. (Functor g, HasField record l us us' v v', RecElemFCtx record ElField) => Label l -> (v -> g v') -> record ElField us -> g (record ElField us')
rlensf :: forall l v record g us. (Functor g, HasField record l us us v v, RecElemFCtx record ElField) => Label l -> (v -> g v) -> record ElField us -> g (record ElField us)
(=:=) :: KnownSymbol s => Label (s :: Symbol) -> a -> FieldRec '['(s, a)]
data SField (field :: k) = SField
type family FieldType l fs where ...
type HasField record l fs fs' v v' = (RecElem record (l ::: v) (l ::: v') fs fs' (RIndex (l ::: v) fs), FieldType l fs ~ v, FieldType l fs' ~ v')
data Label (a :: Symbol) = Label
class (KnownSymbol (Fst a), a ~ '(Fst a, Snd a)) => KnownField a
type AllFields fs = (RPureConstrained KnownField fs, RecApplicative fs, RApply fs)
rmapf :: AllFields fs => (forall a. KnownField a => f a -> g a) -> Rec f fs -> Rec g fs
type family Unlabeled ts where ...
class StripFieldNames ts where
- stripNames :: Rec ElField ts -> Rec Identity (Unlabeled ts)
- stripNames' :: Functor f => Rec (f :. ElField) ts -> Rec f (Unlabeled ts)
- withNames :: Rec Identity (Unlabeled ts) -> Rec ElField ts
- withNames' :: Functor f => Rec f (Unlabeled ts) -> Rec (f :. ElField) ts
rpuref :: AllFields fs => (forall a. KnownField a => f a) -> Rec f fs
(<<$$>>) :: AllFields fs => (forall a. KnownField a => f a -> g a) -> Rec f fs -> Rec g fs
rlabels :: AllFields fs => Rec (Const String) fs

Documentation

type (:::) a b = '(a, b) Source #

Alias for Field spec

type FieldRec = Rec ElField Source #

A record of named fields.

type AFieldRec ts = ARec ElField ts Source #

An ARec of named fields to provide constant-time field access.

type HList = Rec Identity Source #

Heterogeneous list whose elements are evaluated during list construction.

type LazyHList = Rec Thunk Source #

Heterogeneous list whose elements are left as-is during list construction (cf. HList).

getField :: ElField '(s, t) -> t Source #

Get the data payload of an ElField.

getLabel :: forall s t. ElField '(s, t) -> String Source #

Get the label name of an ElField.

fieldMap :: (a -> b) -> ElField '(s, a) -> ElField '(s, b) Source #

ElField is isomorphic to a functor something like Compose ElField ('(,) s).

traverseField :: (KnownSymbol s, Functor f) => (a -> b) -> f (ElField '(s, a)) -> ElField '(s, f b) Source #

Something in the spirit of traverse for ElField whose kind fights the standard library.

rfield :: Functor f => (a -> f b) -> ElField '(s, a) -> f (ElField '(s, b)) Source #

Lens for an ElField's data payload.

(=:) :: KnownSymbol l => Label (l :: Symbol) -> (v :: *) -> ElField (l ::: v) infix 8 Source #

Operator for creating an ElField. With the -XOverloadedLabels extension, this permits usage such as, #foo =: 23 to produce a value of type ElField ("foo" ::: Int).

rgetf :: forall l f v record us. (HasField record l us us v v, RecElemFCtx record f) => Label l -> record f us -> f (l ::: v) Source #

Get a named field from a record.

rvalf :: (HasField record l us us v v, RecElemFCtx record ElField) => Label l -> record ElField us -> v Source #

Get the value associated with a named field from a record.

rputf' :: forall l v v' record us us'. (HasField record l us us' v v', KnownSymbol l, RecElemFCtx record ElField) => Label l -> v' -> record ElField us -> record ElField us' Source #

Set a named field. rputf' #foo 23 sets the field named #foo to 23.

rputf :: forall l v record us. (HasField record l us us v v, KnownSymbol l, RecElemFCtx record ElField) => Label l -> v -> record ElField us -> record ElField us Source #

Set a named field without changing its type. rputf #foo 23 sets the field named #foo to 23.

rlensfL' :: forall l v v' record g f us us'. (Functor g, HasField record l us us' v v', RecElemFCtx record f) => Label l -> (f (l ::: v) -> g (f (l ::: v'))) -> record f us -> g (record f us') Source #

A lens into a Rec identified by a Label.

rlensfL :: forall l v record g f us. (Functor g, HasField record l us us v v, RecElemFCtx record f) => Label l -> (f (l ::: v) -> g (f (l ::: v))) -> record f us -> g (record f us) Source #

A type-preserving lens into a Rec identified by a Label.

rlensf' :: forall l v v' record g us us'. (Functor g, HasField record l us us' v v', RecElemFCtx record ElField) => Label l -> (v -> g v') -> record ElField us -> g (record ElField us') Source #

A lens into the payload value of a Rec field identified by a Label.

rlensf :: forall l v record g us. (Functor g, HasField record l us us v v, RecElemFCtx record ElField) => Label l -> (v -> g v) -> record ElField us -> g (record ElField us) Source #

A type-preserving lens into the payload value of a Rec field identified by a Label.

(=:=) :: KnownSymbol s => Label (s :: Symbol) -> a -> FieldRec '['(s, a)] Source #

Shorthand for a FieldRec with a single field.

data SField (field :: k) Source #

A proxy for field types.

Constructors

SField

Instances

Eq (SField a) Source #
Instance details Defined in Data.Vinyl.Derived Methods (==) :: SField a -> SField a -> Bool # (/=) :: SField a -> SField a -> Bool #
Ord (SField a) Source #
Instance details Defined in Data.Vinyl.Derived Methods compare :: SField a -> SField a -> Ordering # (<) :: SField a -> SField a -> Bool # (<=) :: SField a -> SField a -> Bool # (>) :: SField a -> SField a -> Bool # (>=) :: SField a -> SField a -> Bool # max :: SField a -> SField a -> SField a # min :: SField a -> SField a -> SField a #
KnownSymbol s => Show (SField ((,) s t)) Source #
Instance details Defined in Data.Vinyl.Derived Methods showsPrec :: Int -> SField (s, t) -> ShowS # show :: SField (s, t) -> String # showList :: [SField (s, t)] -> ShowS #

type family FieldType l fs where ... Source #

Equations

FieldType l '[] = TypeError ((Text "Cannot find label " :<>: ShowType l) :<>: Text " in fields")
FieldType l ((l ::: v) ': fs) = v
FieldType l ((l' ::: v') ': fs) = FieldType l fs

type HasField record l fs fs' v v' = (RecElem record (l ::: v) (l ::: v') fs fs' (RIndex (l ::: v) fs), FieldType l fs ~ v, FieldType l fs' ~ v') Source #

Constraint that a label is associated with a particular type in a record.

data Label (a :: Symbol) Source #

Proxy for label type

Constructors

Label

Instances

s ~ s' => IsLabel s (Label s') Source #
Instance details Defined in Data.Vinyl.Derived Methods fromLabel :: Label s' #
Eq (Label a) Source #
Instance details Defined in Data.Vinyl.Derived Methods (==) :: Label a -> Label a -> Bool # (/=) :: Label a -> Label a -> Bool #
Show (Label a) Source #
Instance details Defined in Data.Vinyl.Derived Methods showsPrec :: Int -> Label a -> ShowS # show :: Label a -> String # showList :: [Label a] -> ShowS #

class (KnownSymbol (Fst a), a ~ '(Fst a, Snd a)) => KnownField a Source #

Defines a constraint that lets us extract the label from an ElField. Used in rmapf and rpuref.

Instances

KnownSymbol l => KnownField (l ::: v :: (Symbol, k)) Source #
Instance details Defined in Data.Vinyl.Derived

type AllFields fs = (RPureConstrained KnownField fs, RecApplicative fs, RApply fs) Source #

Shorthand for working with records of fields as in rmapf and rpuref.

rmapf :: AllFields fs => (forall a. KnownField a => f a -> g a) -> Rec f fs -> Rec g fs Source #

Map a function between functors across a Rec taking advantage of knowledge that each element is an ElField.

type family Unlabeled ts where ... Source #

Remove the first component (e.g. the label) from a type-level list of pairs.

Equations

Unlabeled '[] = '[]
Unlabeled ('(s, x) ': xs) = x ': Unlabeled xs

class StripFieldNames ts where Source #

Facilities for removing and replacing the type-level label, or column name, part of a record.

Methods

stripNames :: Rec ElField ts -> Rec Identity (Unlabeled ts) Source #

stripNames' :: Functor f => Rec (f :. ElField) ts -> Rec f (Unlabeled ts) Source #

withNames :: Rec Identity (Unlabeled ts) -> Rec ElField ts Source #

withNames' :: Functor f => Rec f (Unlabeled ts) -> Rec (f :. ElField) ts Source #

Instances

StripFieldNames ([] :: [(Symbol, Type)]) Source #
Instance details Defined in Data.Vinyl.Derived Methods stripNames :: Rec ElField [] -> Rec Identity (Unlabeled []) Source # stripNames' :: Functor f => Rec (f :. ElField) [] -> Rec f (Unlabeled []) Source # withNames :: Rec Identity (Unlabeled []) -> Rec ElField [] Source # withNames' :: Functor f => Rec f (Unlabeled []) -> Rec (f :. ElField) [] Source #
(KnownSymbol s, StripFieldNames ts) => StripFieldNames ((,) s t ': ts) Source #
Instance details Defined in Data.Vinyl.Derived Methods stripNames :: Rec ElField ((s, t) ': ts) -> Rec Identity (Unlabeled ((s, t) ': ts)) Source # stripNames' :: Functor f => Rec (f :. ElField) ((s, t) ': ts) -> Rec f (Unlabeled ((s, t) ': ts)) Source # withNames :: Rec Identity (Unlabeled ((s, t) ': ts)) -> Rec ElField ((s, t) ': ts) Source # withNames' :: Functor f => Rec f (Unlabeled ((s, t) ': ts)) -> Rec (f :. ElField) ((s, t) ': ts) Source #

rpuref :: AllFields fs => (forall a. KnownField a => f a) -> Rec f fs Source #

Construct a Rec with ElField elements.

(<<$$>>) :: AllFields fs => (forall a. KnownField a => f a -> g a) -> Rec f fs -> Rec g fs Source #

Operator synonym for rmapf.

rlabels :: AllFields fs => Rec (Const String) fs Source #

Produce a Rec of the labels of a Rec of ElFields.

Specializations for working with an `ARec` of named fields.

Documentation

Specializations for working with an ARec of named fields.

Specializations for working with an `ARec` of named fields.