vinyl-0.12.1: Extensible Records

Safe HaskellNone
LanguageHaskell2010

Data.Vinyl.Core

Description

Core vinyl definitions. The Rec data type is defined here, but also of interest are definitions commonly used functions like rmap, rapply, and rtraverse.

The definitions in this module are written in terms of type classes so that the definitions may be specialized to each record type at which they are used. This usually helps with runtime performance, but can slow down compilation time. If you are experiencing poor compile times, you may wish to try the semantically equivalent definitions in the Data.Vinyl.Recursive module: they should produce the same results given the same inputs as functions defined in this module, but they will not be specialized to your record type. Instead, they treat the record as a list of fields, so will have performance linear in the size of the record.

Synopsis

Documentation

data Rec :: (u -> *) -> [u] -> * where Source #

A record is parameterized by a universe u, an interpretation f and a list of rows rs. The labels or indices of the record are given by inhabitants of the kind u; the type of values at any label r :: u is given by its interpretation f r :: *.

Constructors

RNil :: Rec f '[] 
(:&) :: !(f r) -> !(Rec f rs) -> Rec f (r ': rs) infixr 7 
Instances
RecSubset (Rec :: (k -> Type) -> [k] -> Type) ([] :: [k]) (ss :: [k]) ([] :: [Nat]) Source # 
Instance details

Defined in Data.Vinyl.Lens

Associated Types

type RecSubsetFCtx Rec f :: Constraint Source #

Methods

rsubsetC :: (Functor g, RecSubsetFCtx Rec f) => (Rec f [] -> g (Rec f [])) -> Rec f ss -> g (Rec f ss) Source #

rcastC :: RecSubsetFCtx Rec f => Rec f ss -> Rec f [] Source #

rreplaceC :: RecSubsetFCtx Rec f => Rec f [] -> Rec f ss -> Rec f ss Source #

(RElem r ss i, RSubset rs ss is) => RecSubset (Rec :: (k -> Type) -> [k] -> Type) (r ': rs :: [k]) (ss :: [k]) (i ': is) Source # 
Instance details

Defined in Data.Vinyl.Lens

Associated Types

type RecSubsetFCtx Rec f :: Constraint Source #

Methods

rsubsetC :: (Functor g, RecSubsetFCtx Rec f) => (Rec f (r ': rs) -> g (Rec f (r ': rs))) -> Rec f ss -> g (Rec f ss) Source #

rcastC :: RecSubsetFCtx Rec f => Rec f ss -> Rec f (r ': rs) Source #

rreplaceC :: RecSubsetFCtx Rec f => Rec f (r ': rs) -> Rec f ss -> Rec f ss Source #

RecElem (Rec :: (a -> Type) -> [a] -> Type) (r :: a) (r' :: a) (r ': rs :: [a]) (r' ': rs :: [a]) Z Source # 
Instance details

Defined in Data.Vinyl.Lens

Associated Types

type RecElemFCtx Rec f :: Constraint Source #

Methods

rlensC :: (Functor g, RecElemFCtx Rec f) => (f r -> g (f r')) -> Rec f (r ': rs) -> g (Rec f (r' ': rs)) Source #

rgetC :: (RecElemFCtx Rec f, r ~ r') => Rec f (r ': rs) -> f r Source #

rputC :: RecElemFCtx Rec f => f r' -> Rec f (r ': rs) -> Rec f (r' ': rs) Source #

(RIndex r (s ': rs) ~ S i, RecElem (Rec :: (a -> Type) -> [a] -> Type) r r' rs rs' i) => RecElem (Rec :: (a -> Type) -> [a] -> Type) (r :: a) (r' :: a) (s ': rs :: [a]) (s ': rs' :: [a]) (S i) Source # 
Instance details

Defined in Data.Vinyl.Lens

Associated Types

type RecElemFCtx Rec f :: Constraint Source #

Methods

rlensC :: (Functor g, RecElemFCtx Rec f) => (f r -> g (f r')) -> Rec f (s ': rs) -> g (Rec f (s ': rs')) Source #

rgetC :: (RecElemFCtx Rec f, r ~ r') => Rec f (s ': rs) -> f r Source #

rputC :: RecElemFCtx Rec f => f r' -> Rec f (s ': rs) -> Rec f (s ': rs') Source #

TestCoercion f => TestCoercion (Rec f :: [u] -> Type) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

testCoercion :: Rec f a -> Rec f b -> Maybe (Coercion a b) #

TestEquality f => TestEquality (Rec f :: [u] -> Type) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

testEquality :: Rec f a -> Rec f b -> Maybe (a :~: b) #

(Eq (f r), Eq (Rec f rs)) => Eq (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

(==) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

(/=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

Eq (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

(==) :: Rec f [] -> Rec f [] -> Bool #

(/=) :: Rec f [] -> Rec f [] -> Bool #

(Ord (f r), Ord (Rec f rs)) => Ord (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

compare :: Rec f (r ': rs) -> Rec f (r ': rs) -> Ordering #

(<) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

(<=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

(>) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

(>=) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Bool #

max :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) #

min :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) #

Ord (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

compare :: Rec f [] -> Rec f [] -> Ordering #

(<) :: Rec f [] -> Rec f [] -> Bool #

(<=) :: Rec f [] -> Rec f [] -> Bool #

(>) :: Rec f [] -> Rec f [] -> Bool #

(>=) :: Rec f [] -> Rec f [] -> Bool #

max :: Rec f [] -> Rec f [] -> Rec f [] #

min :: Rec f [] -> Rec f [] -> Rec f [] #

(RMap rs, ReifyConstraint Show f rs, RecordToList rs) => Show (Rec f rs) Source #

Records may be shown insofar as their points may be shown. reifyConstraint is used to great effect here.

Instance details

Defined in Data.Vinyl.Core

Methods

showsPrec :: Int -> Rec f rs -> ShowS #

show :: Rec f rs -> String #

showList :: [Rec f rs] -> ShowS #

Generic (Rec f rs) => Generic (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Associated Types

type Rep (Rec f (r ': rs)) :: Type -> Type #

Methods

from :: Rec f (r ': rs) -> Rep (Rec f (r ': rs)) x #

to :: Rep (Rec f (r ': rs)) x -> Rec f (r ': rs) #

Generic (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Associated Types

type Rep (Rec f []) :: Type -> Type #

Methods

from :: Rec f [] -> Rep (Rec f []) x #

to :: Rep (Rec f []) x -> Rec f [] #

(Semigroup (f r), Semigroup (Rec f rs)) => Semigroup (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

(<>) :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) #

sconcat :: NonEmpty (Rec f (r ': rs)) -> Rec f (r ': rs) #

stimes :: Integral b => b -> Rec f (r ': rs) -> Rec f (r ': rs) #

Semigroup (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

(<>) :: Rec f [] -> Rec f [] -> Rec f [] #

sconcat :: NonEmpty (Rec f []) -> Rec f [] #

stimes :: Integral b => b -> Rec f [] -> Rec f [] #

(Monoid (f r), Monoid (Rec f rs)) => Monoid (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

mempty :: Rec f (r ': rs) #

mappend :: Rec f (r ': rs) -> Rec f (r ': rs) -> Rec f (r ': rs) #

mconcat :: [Rec f (r ': rs)] -> Rec f (r ': rs) #

Monoid (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

mempty :: Rec f [] #

mappend :: Rec f [] -> Rec f [] -> Rec f [] #

mconcat :: [Rec f []] -> Rec f [] #

(Storable (f r), Storable (Rec f rs)) => Storable (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

sizeOf :: Rec f (r ': rs) -> Int #

alignment :: Rec f (r ': rs) -> Int #

peekElemOff :: Ptr (Rec f (r ': rs)) -> Int -> IO (Rec f (r ': rs)) #

pokeElemOff :: Ptr (Rec f (r ': rs)) -> Int -> Rec f (r ': rs) -> IO () #

peekByteOff :: Ptr b -> Int -> IO (Rec f (r ': rs)) #

pokeByteOff :: Ptr b -> Int -> Rec f (r ': rs) -> IO () #

peek :: Ptr (Rec f (r ': rs)) -> IO (Rec f (r ': rs)) #

poke :: Ptr (Rec f (r ': rs)) -> Rec f (r ': rs) -> IO () #

Storable (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

sizeOf :: Rec f [] -> Int #

alignment :: Rec f [] -> Int #

peekElemOff :: Ptr (Rec f []) -> Int -> IO (Rec f []) #

pokeElemOff :: Ptr (Rec f []) -> Int -> Rec f [] -> IO () #

peekByteOff :: Ptr b -> Int -> IO (Rec f []) #

pokeByteOff :: Ptr b -> Int -> Rec f [] -> IO () #

peek :: Ptr (Rec f []) -> IO (Rec f []) #

poke :: Ptr (Rec f []) -> Rec f [] -> IO () #

type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) Source # 
Instance details

Defined in Data.Vinyl.Lens

type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) = ()
type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) Source # 
Instance details

Defined in Data.Vinyl.Lens

type RecSubsetFCtx (Rec :: (k -> Type) -> [k] -> Type) (f :: k -> Type) = ()
type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) Source # 
Instance details

Defined in Data.Vinyl.Lens

type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) = ()
type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) Source # 
Instance details

Defined in Data.Vinyl.Lens

type RecElemFCtx (Rec :: (a -> Type) -> [a] -> Type) (f :: a -> Type) = ()
type Rep (Rec f (r ': rs)) Source # 
Instance details

Defined in Data.Vinyl.Core

type Rep (Rec f ([] :: [u])) Source # 
Instance details

Defined in Data.Vinyl.Core

rappend :: Rec f as -> Rec f bs -> Rec f (as ++ bs) Source #

Two records may be pasted together.

(<+>) :: Rec f as -> Rec f bs -> Rec f (as ++ bs) infixr 5 Source #

A shorthand for rappend.

rcombine :: (RMap rs, RApply rs) => (forall a. m a -> m a -> m a) -> (forall a. f a -> m a) -> (forall a. m a -> g a) -> Rec f rs -> Rec f rs -> Rec g rs Source #

Combine two records by combining their fields using the given function. The first argument is a binary operation for combining two values (e.g. '(<>)'), the second argument takes a record field into the type equipped with the desired operation, the third argument takes the combined value back to a result type.

class RMap rs where Source #

Rec _ rs with labels in kind u gives rise to a functor Hask^u -> Hask; that is, a natural transformation between two interpretation functors f,g may be used to transport a value from Rec f rs to Rec g rs.

Methods

rmap :: (forall x. f x -> g x) -> Rec f rs -> Rec g rs Source #

Instances
RMap ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rmap :: (forall (x :: u0). f x -> g x) -> Rec f [] -> Rec g [] Source #

RMap xs => RMap (x ': xs :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rmap :: (forall (x0 :: u0). f x0 -> g x0) -> Rec f (x ': xs) -> Rec g (x ': xs) Source #

(<<$>>) :: RMap rs => (forall x. f x -> g x) -> Rec f rs -> Rec g rs infixl 8 Source #

A shorthand for rmap.

(<<&>>) :: RMap rs => Rec f rs -> (forall x. f x -> g x) -> Rec g rs Source #

An inverted shorthand for rmap.

class RApply rs where Source #

A record of components f r -> g r may be applied to a record of f to get a record of g.

Methods

rapply :: Rec (Lift (->) f g) rs -> Rec f rs -> Rec g rs Source #

Instances
RApply ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rapply :: Rec (Lift (->) f g) [] -> Rec f [] -> Rec g [] Source #

RApply xs => RApply (x ': xs :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rapply :: Rec (Lift (->) f g) (x ': xs) -> Rec f (x ': xs) -> Rec g (x ': xs) Source #

(<<*>>) :: RApply rs => Rec (Lift (->) f g) rs -> Rec f rs -> Rec g rs infixl 8 Source #

A shorthand for rapply.

class RecApplicative rs where Source #

Given a section of some functor, records in that functor of any size are inhabited.

Methods

rpure :: (forall x. f x) -> Rec f rs Source #

Instances
RecApplicative ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpure :: (forall (x :: u0). f x) -> Rec f [] Source #

RecApplicative rs => RecApplicative (r ': rs :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpure :: (forall (x :: u0). f x) -> Rec f (r ': rs) Source #

rtraverse :: Applicative h => (forall x. f x -> h (g x)) -> Rec f rs -> h (Rec g rs) Source #

A record may be traversed with respect to its interpretation functor. This can be used to yank (some or all) effects from the fields of the record to the outside of the record.

rtraverseIn :: forall h f g rs. (forall a. f a -> g (ApplyToField h a)) -> Rec f rs -> Rec g (MapTyCon h rs) Source #

While rtraverse pulls the interpretation functor out of the record, rtraverseIn pushes the interpretation functor in to each field type. This is particularly useful when you wish to discharge that interpretation on a per-field basis. For instance, rather than a Rec IO '[a,b], you may wish to have a Rec Identity '[IO a, IO b] so that you can evaluate a single field to obtain a value of type Rec Identity '[a, IO b].

rsequenceIn :: forall f g (rs :: [Type]). (Traversable f, Applicative g) => Rec (f :. g) rs -> Rec g (MapTyCon f rs) Source #

Push an outer layer of interpretation functor into each field.

rzipWith :: (RMap xs, RApply xs) => (forall x. f x -> g x -> h x) -> Rec f xs -> Rec g xs -> Rec h xs Source #

Given a natural transformation from the product of f and g to h, we have a natural transformation from the product of Rec f and Rec g to Rec h. You can also think about this operation as zipping two records with the same element types but different interpretations.

class RFoldMap rs where Source #

Map each element of a record to a monoid and combine the results.

Methods

rfoldMapAux :: Monoid m => (forall x. f x -> m) -> m -> Rec f rs -> m Source #

Instances
RFoldMap ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rfoldMapAux :: Monoid m => (forall (x :: u0). f x -> m) -> m -> Rec f [] -> m Source #

RFoldMap xs => RFoldMap (x ': xs :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rfoldMapAux :: Monoid m => (forall (x0 :: u0). f x0 -> m) -> m -> Rec f (x ': xs) -> m Source #

rfoldMap :: forall rs m f. (Monoid m, RFoldMap rs) => (forall x. f x -> m) -> Rec f rs -> m Source #

class RecordToList rs where Source #

A record with uniform fields may be turned into a list.

Methods

recordToList :: Rec (Const a) rs -> [a] Source #

Instances
RecordToList ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

recordToList :: Rec (Const a) [] -> [a] Source #

RecordToList xs => RecordToList (x ': xs :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

recordToList :: Rec (Const a) (x ': xs) -> [a] Source #

data Dict c a where Source #

Wrap up a value with a capability given by its type

Constructors

Dict :: c a => a -> Dict c a 

class ReifyConstraint c f rs where Source #

Sometimes we may know something for all fields of a record, but when you expect to be able to each of the fields, you are then out of luck. Surely given ∀x:u.φ(x) we should be able to recover x:u ⊢ φ(x)! Sadly, the constraint solver is not quite smart enough to realize this and we must make it patently obvious by reifying the constraint pointwise with proof.

Methods

reifyConstraint :: Rec f rs -> Rec (Dict c :. f) rs Source #

Instances
ReifyConstraint c (f :: u -> Type) ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

reifyConstraint :: Rec f [] -> Rec (Dict c :. f) [] Source #

(c (f x), ReifyConstraint c f xs) => ReifyConstraint c (f :: a -> Type) (x ': xs :: [a]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

reifyConstraint :: Rec f (x ': xs) -> Rec (Dict c :. f) (x ': xs) Source #

class RPureConstrained c ts where Source #

Build a record whose elements are derived solely from a constraint satisfied by each.

Methods

rpureConstrained :: (forall a. c a => f a) -> Rec f ts Source #

Instances
RPureConstrained (c :: u -> Constraint) ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpureConstrained :: (forall (a :: u0). c a => f a) -> Rec f [] Source #

(c x, RPureConstrained c xs) => RPureConstrained (c :: a -> Constraint) (x ': xs :: [a]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpureConstrained :: (forall (a0 :: u). c a0 => f a0) -> Rec f (x ': xs) Source #

data DictOnly (c :: k -> Constraint) a where Source #

Capture a type class instance dictionary. See getDict for a way to obtain a DictOnly value from an RPureConstrained constraint.

Constructors

DictOnly :: forall c a. c a => DictOnly c a 

withPairedDict :: (c a => f a -> r) -> Product (DictOnly c) f a -> r Source #

A useful technique is to use 'rmap (Pair (DictOnly MyClass))' on a Rec to pair each field with a type class dictionary for MyClass@. This helper can then be used to eliminate the original.

class RPureConstraints cs ts where Source #

Build a record whose elements are derived solely from a list of constraint constructors satisfied by each.

Methods

rpureConstraints :: (forall a. AllSatisfied cs a => f a) -> Rec f ts Source #

Instances
RPureConstraints (cs :: k) ([] :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpureConstraints :: (forall (a :: u0). AllSatisfied cs a => f a) -> Rec f [] Source #

(AllSatisfied cs t, RPureConstraints cs ts) => RPureConstraints (cs :: k) (t ': ts :: [u]) Source # 
Instance details

Defined in Data.Vinyl.Core

Methods

rpureConstraints :: (forall (a :: u0). AllSatisfied cs a => f a) -> Rec f (t ': ts) Source #