Safe Haskell	None
Language	Haskell2010

Data.Reproject

Contents

Type lifting
Internal helpers

Synopsis

Documentation

class Proj label ty where Source #

A named projection on a type. Very similar to Has but w/o a setter

Minimal complete definition

applyProj

Associated Types

type ProjTy label ty Source #

Methods

applyProj :: LblProxy label -> ty -> ProjTy label ty Source #

data Projection t a where Source #

A list of projections to be applied to a type

Constructors

ProjNil :: Projection t '[]
Combine :: (KnownSymbol a, Proj a t) => LblProxy (a :: Symbol) -> Projection t b -> Projection t (a ': b)

Instances

Eq (Projection t a) Source #
Methods (==) :: Projection t a -> Projection t a -> Bool # (/=) :: Projection t a -> Projection t a -> Bool #
(Proj a t, KnownSymbol a, Read (Projection t as)) => Read (Projection t ((:) Symbol a as)) Source #
Methods readsPrec :: Int -> ReadS (Projection t ((Symbol ': a) as)) # readList :: ReadS [Projection t ((Symbol ': a) as)] # readPrec :: ReadPrec (Projection t ((Symbol ': a) as)) # readListPrec :: ReadPrec [Projection t ((Symbol ': a) as)] #
Read (Projection t ([] Symbol)) Source #
Methods readsPrec :: Int -> ReadS (Projection t [Symbol]) # readList :: ReadS [Projection t [Symbol]] # readPrec :: ReadPrec (Projection t [Symbol]) # readListPrec :: ReadPrec [Projection t [Symbol]] #
Show (Projection t a) Source #
Methods showsPrec :: Int -> Projection t a -> ShowS # show :: Projection t a -> String # showList :: [Projection t a] -> ShowS #

type family HasProj (a :: [Symbol]) t = (r :: Constraint) where ... Source #

Construct a constraint that asserts that for all labels a projection for type t exists

Equations

HasProj '[] t = True ~ True
HasProj (x ': xs) t = (Proj x t, HasProj xs t)

proj :: forall t lbls. HasProj lbls t => Projection t lbls -> t -> Rec t lbls Source #

Apply all projections to a type and return them in a Labels compatible tuple. USe projVal to read single projections from it. Using OverloadedLabels is advised.

projVal :: forall label key more v t. ReadRec label (IsEqLabel key label) (Rec t (key ': more)) v => LblProxy label -> Rec t (key ': more) -> v Source #

Read a projection from a projection record

(@@) :: (KnownSymbol a, Proj a t) => LblProxy (a :: Symbol) -> Projection t b -> Projection t (a ': b) infixr 5 Source #

Infix alias for Combine

Type lifting

data AnyProj t Source #

Constructors

(Typeable x, HasProj x t) => AnyProj
Fields unAnyProj :: Projection t x

Instances

Typeable * t => Eq (AnyProj t) Source #
Methods (==) :: AnyProj t -> AnyProj t -> Bool # (/=) :: AnyProj t -> AnyProj t -> Bool #
Show (AnyProj t) Source #
Methods showsPrec :: Int -> AnyProj t -> ShowS # show :: AnyProj t -> String # showList :: [AnyProj t] -> ShowS #

data AnyRec t Source #

Constructors

Typeable x => AnyRec
Fields unAnyRec :: Rec t x

runAnyProj :: t -> AnyProj t -> AnyRec t Source #

anyToTypedProj :: forall t x. (HasProj x t, Typeable x, Typeable t) => (AnyProj t -> AnyRec t) -> Projection t x -> Rec t x Source #

anyToTypedProjM :: forall m t x. (Monad m, HasProj x t, Typeable x, Typeable t) => (AnyProj t -> m (AnyRec t)) -> Projection t x -> m (Rec t x) Source #

Internal helpers

data LblProxy t Source #

Constructors

LblProxy

Instances

(~) Symbol l l' => IsLabel l (LblProxy l') Source #
Methods fromLabel :: Proxy# Symbol l -> LblProxy l' #
Eq (LblProxy t) Source #
Methods (==) :: LblProxy t -> LblProxy t -> Bool # (/=) :: LblProxy t -> LblProxy t -> Bool #
Ord (LblProxy t) Source #
Methods compare :: LblProxy t -> LblProxy t -> Ordering # (<) :: LblProxy t -> LblProxy t -> Bool # (<=) :: LblProxy t -> LblProxy t -> Bool # (>) :: LblProxy t -> LblProxy t -> Bool # (>=) :: LblProxy t -> LblProxy t -> Bool # max :: LblProxy t -> LblProxy t -> LblProxy t # min :: LblProxy t -> LblProxy t -> LblProxy t #
Read (LblProxy t) Source #
Methods readsPrec :: Int -> ReadS (LblProxy t) # readList :: ReadS [LblProxy t] # readPrec :: ReadPrec (LblProxy t) # readListPrec :: ReadPrec [LblProxy t] #
Show (LblProxy t) Source #
Methods showsPrec :: Int -> LblProxy t -> ShowS # show :: LblProxy t -> String # showList :: [LblProxy t] -> ShowS #

class ReadRec label eq r v | label r -> v where Source #

Minimal complete definition

projVal'

Methods

projVal' :: LblProxy label -> p eq -> r -> v Source #

Instances

((~) * (RecValTy label t ((:) Symbol key more)) v, ReadRec label (IsEqLabel key label) (Rec t ((:) Symbol key more)) v) => ReadRec label False (Rec t ((:) Symbol l1 ((:) Symbol key more))) v Source #
Methods projVal' :: LblProxy label -> p False -> Rec t ((Symbol ': l1) ((Symbol ': key) more)) -> v Source #
(~) * (ProjTy key t) v => ReadRec label True (Rec t ((:) Symbol key more)) v Source #
Methods projVal' :: LblProxy label -> p True -> Rec t ((Symbol ': key) more) -> v Source #

type family RecValTy label (t :: *) (lbls :: [Symbol]) where ... Source #

Equations

RecValTy label t lbls = RecValTyH label lbls (RecTys t lbls)

type family IsEqLabel (label :: Symbol) (label2 :: Symbol) = (r :: Bool) where ... Source #

Equations

IsEqLabel l l = True
IsEqLabel l l2 = False

data Rec t labels where Source #

Constructors

RNil :: Rec t '[]
RCons :: KnownSymbol s => LblProxy s -> ProjTy s t -> Rec t ss -> Rec t (s ': ss)

Instances

((~) * (RecValTy label t ((:) Symbol key more)) v, ReadRec label (IsEqLabel key label) (Rec t ((:) Symbol key more)) v) => ReadRec label False (Rec t ((:) Symbol l1 ((:) Symbol key more))) v Source #
Methods projVal' :: LblProxy label -> p False -> Rec t ((Symbol ': l1) ((Symbol ': key) more)) -> v Source #
(~) * (ProjTy key t) v => ReadRec label True (Rec t ((:) Symbol key more)) v Source #
Methods projVal' :: LblProxy label -> p True -> Rec t ((Symbol ': key) more) -> v Source #
(Eq (Rec t ls), Eq (ProjTy l t)) => Eq (Rec t ((:) Symbol l ls)) Source #
Methods (==) :: Rec t ((Symbol ': l) ls) -> Rec t ((Symbol ': l) ls) -> Bool # (/=) :: Rec t ((Symbol ': l) ls) -> Rec t ((Symbol ': l) ls) -> Bool #
Eq (Rec c ([] Symbol)) Source #
Methods (==) :: Rec c [Symbol] -> Rec c [Symbol] -> Bool # (/=) :: Rec c [Symbol] -> Rec c [Symbol] -> Bool #
(Show (ProjTy l t), Show (Rec t ls)) => Show (Rec t ((:) Symbol l ls)) Source #
Methods showsPrec :: Int -> Rec t ((Symbol ': l) ls) -> ShowS # show :: Rec t ((Symbol ': l) ls) -> String # showList :: [Rec t ((Symbol ': l) ls)] -> ShowS #
Show (Rec c ([] Symbol)) Source #
Methods showsPrec :: Int -> Rec c [Symbol] -> ShowS # show :: Rec c [Symbol] -> String # showList :: [Rec c [Symbol]] -> ShowS #