Safe Haskell | None |
---|---|
Language | Haskell2010 |
Main module of generics-sop
In most cases, you will probably want to import just this module,
and possibly Generics.SOP.TH if you want to use Template Haskell
to generate Generic
instances for you.
Generic programming with sums of products
You need this library if you want to define your own generic functions in the sum-of-products SOP style. Generic programming in the SOP style follows the following idea:
- A large class of datatypes can be viewed in a uniform, structured
way: the choice between constructors is represented using an n-ary
sum (called
NS
), and the arguments of each constructor are represented using an n-ary product (calledNP
). - The library captures the notion of a datatype being representable
in the following way. There is a class
Generic
, which for a given datatypeA
, associates the isomorphic SOP representation with the original type under the name
. The class also provides functionsRep
Afrom
andto
that convert betweenA
and
and witness the isomorphism.Rep
A - Since all
Rep
types are sums of products, you can define functions over them by performing induction on the structure, or by using predefined combinators that the library provides. Such functions then work for allRep
types. - By combining the conversion functions
from
andto
with the function that works onRep
types, we obtain a function that works on all types that are in theGeneric
class. - Most types can very easily be made an instance of
Generic
. For example, if the datatype can be represented using GHC's built-in approach to generic programming and has an instance for theGeneric
class from module GHC.Generics, then an instance of the SOPGeneric
can automatically be derived. There is also Template Haskell code in Generics.SOP.TH that allows to auto-generate an instance ofGeneric
for most types.
Example
Instantiating a datatype for use with SOP generics
Let's assume we have the datatypes:
data A = C Bool | D A Int | E (B ()) data B a = F | G a Char Bool
To create Generic
instances for A
and B
via GHC.Generics, we say
{-# LANGUAGE DeriveGeneric #-} import qualified GHC.Generics as GHC import Generics.SOP data A = C Bool | D A Int | E (B ()) deriving (Show, GHC.Generic) data B a = F | G a Char Bool deriving (Show, GHC.Generic) instance Generic A -- empty instance Generic (B a) -- empty
Now we can convert between A
and
(and between Rep
AB
and
).
For example,Rep
B
>>>
from (D (C True) 3) :: Rep A
SOP (S (Z (I (C True) :* I 3 :* Nil)))>>>
to it :: A
D (C True) 3
Note that the transformation is shallow: In D (C True) 3
, the
inner value C True
of type A
is not affected by the
transformation.
For more details about
, have a look at the
Generics.SOP.Universe module.Rep
A
Defining a generic function
As an example of a generic function, let us define a generic
version of rnf
from the deepseq
package.
The type of rnf
is
NFData a => a -> ()
and the idea is that for a term x
of type a
in the
NFData
class, rnf x
forces complete evaluation
of x
(i.e., evaluation to normal form), and returns ()
.
We call the generic version of this function grnf
. A direct
definition in SOP style, making use of structural recursion on the
sums and products, looks as follows:
grnf :: (Generic
a,All2
NFData (Code
a)) => a -> () grnf x = grnfS (from
x) grnfS :: (All2
NFData xss) =>SOP
I
xss -> () grnfS (SOP
(Z
xs)) = grnfP xs grnfS (SOP
(S
xss)) = grnfS (SOP
xss) grnfP :: (All
NFData xs) =>NP
I
xs -> () grnfPNil
= () grnfP (I
x:*
xs) = x `deepseq` (grnfP xs)
The grnf
function performs the conversion between a
and
by applying Rep
afrom
and then applies grnfS
. The type of grnf
indicates that a
must be in the Generic
class so that we can
apply from
, and that all the components of a
(i.e., all the types
that occur as constructor arguments) must be in the NFData
class
(All2
).
The function grnfS
traverses the outer sum structure of the
sum of products (note that
). It
encodes which constructor was used to construct the original
argument of type Rep
a = SOP
I
(Code
a)a
. Once we've found the constructor in question
(Z
), we traverse the arguments of that constructor using grnfP
.
The function grnfP
traverses the product structure of the
constructor arguments. Each argument is evaluated using the
deepseq
function from the NFData
class. This requires that all components of the product must be
in the NFData
class (All
) and triggers the corresponding
constraints on the other functions. Once the end of the product
is reached (Nil
), we return ()
.
Defining a generic function using combinators
In many cases, generic functions can be written in a much more concise way by avoiding the explicit structural recursion and resorting to the powerful combinators provided by this library instead.
For example, the grnf
function can also be defined as a one-liner
as follows:
grnf :: (Generic
a,All2
NFData (Code
a)) => a -> () grnf =rnf
.hcollapse
.hcmap
(Proxy
::Proxy
NFData) (mapIK
rnf) .from
mapIK
and friends (mapII
, mapKI
, etc.) are small helpers for working
with I
and K
functors, for example mapIK
is defined as
mapIK
f = \ (I
x) -> K
(f x)
The following interaction should provide an idea of the individual transformation steps:
>>>
let x = G 2.5 'A' False :: B Double
>>>
from x
SOP (S (Z (I 2.5 :* I 'A' :* I False :* Nil)))>>>
hcmap (Proxy :: Proxy NFData) (mapIK rnf) it
SOP (S (Z (K () :* K () :* K () :* Nil)))>>>
hcollapse it
[(),(),()]>>>
rnf it
()
The from
call converts into the structural representation.
Via hcmap
, we apply rnf
to all the components. The result
is a sum of products of the same shape, but the components are
no longer heterogeneous (I
), but homogeneous (
). A
homogeneous structure can be collapsed (K
()hcollapse
) into a
normal Haskell list. Finally, rnf
actually forces evaluation
of this list (and thereby actually drives the evaluation of all
the previous steps) and produces the final result.
Using a generic function
We can directly invoke grnf
on any type that is an instance of
class Generic
.
>>>
grnf (G 2.5 'A' False)
()>>>
grnf (G 2.5 undefined False)
*** Exception: Prelude.undefined ...
Note that the type of grnf
requires that all components of the
type are in the NFData
class. For a recursive
datatype such as B
, this means that we have to make A
(and in this case, also B
) an instance of NFData
in order to be able to use the grnf
function. But we can use grnf
to supply the instance definitions:
instance NFData A where rnf = grnf instance NFData a => NFData (B a) where rnf = grnf
More examples
The best way to learn about how to define generic functions in the SOP style is to look at a few simple examples. Examples are provided by the following packages:
basic-sop
basic examples,pretty-sop
generic pretty printing,lens-sop
generically computed lenses,json-sop
generic JSON conversions.
The generic functions in these packages use a wide variety of the combinators that are offered by the library.
Paper
A detailed description of the ideas behind this library is provided by the paper:
- Edsko de Vries and Andres Löh. True Sums of Products. Workshop on Generic Programming (WGP) 2014.
Synopsis
- class All SListI (Code a) => Generic (a :: Type) where
- type Rep a = SOP I (Code a)
- type IsProductType (a :: Type) (xs :: [Type]) = (Generic a, Code a ~ '[xs])
- type ProductCode (a :: Type) = Head (Code a)
- productTypeFrom :: IsProductType a xs => a -> NP I xs
- productTypeTo :: IsProductType a xs => NP I xs -> a
- type IsEnumType (a :: Type) = (Generic a, All ((~) '[]) (Code a))
- enumTypeFrom :: IsEnumType a => a -> NS (K ()) (Code a)
- enumTypeTo :: IsEnumType a => NS (K ()) (Code a) -> a
- type IsWrappedType (a :: Type) (x :: Type) = (Generic a, Code a ~ '['[x]])
- type WrappedCode (a :: Type) = Head (Head (Code a))
- wrappedTypeFrom :: IsWrappedType a x => a -> x
- wrappedTypeTo :: IsWrappedType a x => x -> a
- type IsNewtype (a :: Type) (x :: Type) = (IsWrappedType a x, Coercible a x)
- newtypeFrom :: IsNewtype a x => a -> x
- newtypeTo :: IsNewtype a x => x -> a
- data NP (a :: k -> Type) (b :: [k]) where
- data NS (a :: k -> Type) (b :: [k]) where
- newtype SOP (f :: k -> Type) (xss :: [[k]]) = SOP (NS (NP f) xss)
- unSOP :: forall k (f :: k -> Type) (xss :: [[k]]). SOP f xss -> NS (NP f) xss
- newtype POP (f :: k -> Type) (xss :: [[k]]) = POP (NP (NP f) xss)
- unPOP :: forall k (f :: k -> Type) (xss :: [[k]]). POP f xss -> NP (NP f) xss
- data DatatypeInfo :: [[Type]] -> Type where
- ADT :: ModuleName -> DatatypeName -> NP ConstructorInfo xss -> POP StrictnessInfo xss -> DatatypeInfo xss
- Newtype :: ModuleName -> DatatypeName -> ConstructorInfo '[x] -> DatatypeInfo '['[x]]
- moduleName :: DatatypeInfo xss -> ModuleName
- datatypeName :: DatatypeInfo xss -> DatatypeName
- constructorInfo :: DatatypeInfo xss -> NP ConstructorInfo xss
- data ConstructorInfo :: [Type] -> Type where
- Constructor :: SListI xs => ConstructorName -> ConstructorInfo xs
- Infix :: ConstructorName -> Associativity -> Fixity -> ConstructorInfo '[x, y]
- Record :: SListI xs => ConstructorName -> NP FieldInfo xs -> ConstructorInfo xs
- constructorName :: ConstructorInfo xs -> ConstructorName
- data FieldInfo :: Type -> Type where
- fieldName :: FieldInfo a -> FieldName
- class Generic a => HasDatatypeInfo a where
- type DatatypeInfoOf a :: DatatypeInfo
- datatypeInfo :: proxy a -> DatatypeInfo (Code a)
- type DatatypeName = String
- type ModuleName = String
- type ConstructorName = String
- type FieldName = String
- data Associativity
- type Fixity = Int
- class HPure (h :: (k -> Type) -> l -> Type) where
- hd :: forall k f (x :: k) (xs :: [k]). NP f (x ': xs) -> f x
- tl :: forall k (f :: k -> Type) (x :: k) (xs :: [k]). NP f (x ': xs) -> NP f xs
- type Projection (f :: k -> Type) (xs :: [k]) = (K (NP f xs) :: k -> Type) -.-> f
- projections :: forall k (xs :: [k]) (f :: k -> Type). SListI xs => NP (Projection f xs) xs
- shiftProjection :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Projection f xs a2 -> Projection f (x ': xs) a2
- newtype ((f :: k -> Type) -.-> (g :: k -> Type)) (a :: k) = Fn {
- apFn :: f a -> g a
- fn :: forall k f (a :: k) f'. (f a -> f' a) -> (f -.-> f') a
- fn_2 :: forall k f (a :: k) f' f''. (f a -> f' a -> f'' a) -> (f -.-> (f' -.-> f'')) a
- fn_3 :: forall k f (a :: k) f' f'' f'''. (f a -> f' a -> f'' a -> f''' a) -> (f -.-> (f' -.-> (f'' -.-> f'''))) a
- fn_4 :: forall k f (a :: k) f' f'' f''' f''''. (f a -> f' a -> f'' a -> f''' a -> f'''' a) -> (f -.-> (f' -.-> (f'' -.-> (f''' -.-> f'''')))) a
- type family Prod (h :: (k -> Type) -> l -> Type) :: (k -> Type) -> l -> Type
- class (Prod (Prod h) ~ Prod h, HPure (Prod h)) => HAp (h :: (k -> Type) -> l -> Type) where
- hliftA :: forall k l h (xs :: l) f f'. (SListIN (Prod h) xs, HAp h) => (forall (a :: k). f a -> f' a) -> h f xs -> h f' xs
- hliftA2 :: forall k l h (xs :: l) f f' f''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs
- hliftA3 :: forall k l h (xs :: l) f f' f'' f'''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs
- hcliftA :: forall k l h c (xs :: l) proxy f f'. (AllN (Prod h) c xs, HAp h) => proxy c -> (forall (a :: k). c a => f a -> f' a) -> h f xs -> h f' xs
- hcliftA2 :: forall k l h c (xs :: l) proxy f f' f''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs
- hcliftA3 :: forall k l h c (xs :: l) proxy f f' f'' f'''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs
- hmap :: forall k l h (xs :: l) f f'. (SListIN (Prod h) xs, HAp h) => (forall (a :: k). f a -> f' a) -> h f xs -> h f' xs
- hzipWith :: forall k l h (xs :: l) f f' f''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs
- hzipWith3 :: forall k l h (xs :: l) f f' f'' f'''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs
- hcmap :: forall k l h c (xs :: l) proxy f f'. (AllN (Prod h) c xs, HAp h) => proxy c -> (forall (a :: k). c a => f a -> f' a) -> h f xs -> h f' xs
- hczipWith :: forall k l h c (xs :: l) proxy f f' f''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs
- hczipWith3 :: forall k l h c (xs :: l) proxy f f' f'' f'''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs
- type Injection (f :: k -> Type) (xs :: [k]) = f -.-> (K (NS f xs) :: k -> Type)
- injections :: forall k (xs :: [k]) (f :: k -> Type). SListI xs => NP (Injection f xs) xs
- shift :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Injection f xs a2 -> Injection f (x ': xs) a2
- shiftInjection :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Injection f xs a2 -> Injection f (x ': xs) a2
- type family UnProd (h :: (k -> Type) -> l -> Type) :: (k -> Type) -> l -> Type
- class UnProd (Prod h) ~ h => HApInjs (h :: (k -> Type) -> l -> Type) where
- apInjs_NP :: forall k (xs :: [k]) (f :: k -> Type). SListI xs => NP f xs -> [NS f xs]
- apInjs_POP :: forall k (xss :: [[k]]) (f :: k -> Type). SListI xss => POP f xss -> [SOP f xss]
- unZ :: forall k f (x :: k). NS f '[x] -> f x
- class HIndex (h :: (k -> Type) -> l -> Type) where
- type Ejection (f :: k -> Type) (xs :: [k]) = (K (NS f xs) :: k -> Type) -.-> (Maybe :.: f)
- ejections :: forall k (xs :: [k]) (f :: k -> Type). SListI xs => NP (Ejection f xs) xs
- shiftEjection :: forall a1 (f :: a1 -> Type) (x :: a1) (xs :: [a1]) (a2 :: a1). Ejection f xs a2 -> Ejection f (x ': xs) a2
- hcliftA' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f'. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs) -> h f xss -> h f' xss
- hcliftA2' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f' f''. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs -> f'' xs) -> Prod h f xss -> h f' xss -> h f'' xss
- hcliftA3' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f' f'' f'''. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs -> f'' xs -> f''' xs) -> Prod h f xss -> Prod h f' xss -> h f'' xss -> h f''' xss
- compare_NS :: forall k r f g (xs :: [k]). r -> (forall (x :: k). f x -> g x -> r) -> r -> NS f xs -> NS g xs -> r
- ccompare_NS :: forall k c proxy r f g (xs :: [k]). All c xs => proxy c -> r -> (forall (x :: k). c x => f x -> g x -> r) -> r -> NS f xs -> NS g xs -> r
- compare_SOP :: forall k r (f :: k -> Type) (g :: k -> Type) (xss :: [[k]]). r -> (forall (xs :: [k]). NP f xs -> NP g xs -> r) -> r -> SOP f xss -> SOP g xss -> r
- ccompare_SOP :: forall k (c :: k -> Constraint) proxy r (f :: k -> Type) (g :: k -> Type) (xss :: [[k]]). All2 c xss => proxy c -> r -> (forall (xs :: [k]). All c xs => NP f xs -> NP g xs -> r) -> r -> SOP f xss -> SOP g xss -> r
- type family CollapseTo (h :: (k -> Type) -> l -> Type) x
- class HCollapse (h :: (k -> Type) -> l -> Type) where
- hcollapse :: forall (xs :: l) a. SListIN h xs => h (K a :: k -> Type) xs -> CollapseTo h a
- class HTraverse_ (h :: (k -> Type) -> l -> Type) where
- hctraverse_ :: forall c (xs :: l) g proxy f. (AllN h c xs, Applicative g) => proxy c -> (forall (a :: k). c a => f a -> g ()) -> h f xs -> g ()
- htraverse_ :: forall (xs :: l) g f. (SListIN h xs, Applicative g) => (forall (a :: k). f a -> g ()) -> h f xs -> g ()
- hcfoldMap :: forall k l h c (xs :: l) m proxy f. (HTraverse_ h, AllN h c xs, Monoid m) => proxy c -> (forall (a :: k). c a => f a -> m) -> h f xs -> m
- hcfor_ :: forall k l h c (xs :: l) g proxy f. (HTraverse_ h, AllN h c xs, Applicative g) => proxy c -> h f xs -> (forall (a :: k). c a => f a -> g ()) -> g ()
- class HAp h => HSequence (h :: (k -> Type) -> l -> Type) where
- hsequence' :: forall (xs :: l) f (g :: k -> Type). (SListIN h xs, Applicative f) => h (f :.: g) xs -> f (h g xs)
- hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN h c xs, Applicative g) => proxy c -> (forall (a :: k). c a => f a -> g (f' a)) -> h f xs -> g (h f' xs)
- htraverse' :: forall (xs :: l) g f f'. (SListIN h xs, Applicative g) => (forall (a :: k). f a -> g (f' a)) -> h f xs -> g (h f' xs)
- hsequence :: forall l h (xs :: l) f. (SListIN h xs, SListIN (Prod h) xs, HSequence h, Applicative f) => h f xs -> f (h I xs)
- hsequenceK :: forall k l h (xs :: l) f a. (SListIN h xs, SListIN (Prod h) xs, Applicative f, HSequence h) => h (K (f a) :: k -> Type) xs -> f (h (K a :: k -> Type) xs)
- hctraverse :: forall l h c (xs :: l) g proxy f. (HSequence h, AllN h c xs, Applicative g) => proxy c -> (forall a. c a => f a -> g a) -> h f xs -> g (h I xs)
- hcfor :: forall l h c (xs :: l) g proxy f. (HSequence h, AllN h c xs, Applicative g) => proxy c -> h f xs -> (forall a. c a => f a -> g a) -> g (h I xs)
- class HExpand (h :: (k -> Type) -> l -> Type) where
- class ((Same h1 :: (k2 -> Type) -> l2 -> Type) ~ h2, (Same h2 :: (k1 -> Type) -> l1 -> Type) ~ h1) => HTrans (h1 :: (k1 -> Type) -> l1 -> Type) (h2 :: (k2 -> Type) -> l2 -> Type) where
- htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod h1) c xs ys => proxy c -> (forall (x :: k1) (y :: k2). c x y => f x -> g y) -> h1 f xs -> h2 g ys
- hcoerce :: forall (f :: k1 -> Type) (g :: k2 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod h1) (LiftedCoercible f g) xs ys, HTrans h1 h2) => h1 f xs -> h2 g ys
- hfromI :: forall l1 k2 l2 h1 (f :: k2 -> Type) (xs :: l1) (ys :: l2) h2. (AllZipN (Prod h1) (LiftedCoercible I f) xs ys, HTrans h1 h2) => h1 I xs -> h2 f ys
- htoI :: forall k1 l1 l2 h1 (f :: k1 -> Type) (xs :: l1) (ys :: l2) h2. (AllZipN (Prod h1) (LiftedCoercible f I) xs ys, HTrans h1 h2) => h1 f xs -> h2 I ys
- fromList :: forall k (xs :: [k]) a. SListI xs => [a] -> Maybe (NP (K a :: k -> Type) xs)
- newtype K a (b :: k) = K a
- unK :: forall k a (b :: k). K a b -> a
- newtype I a = I a
- unI :: I a -> a
- newtype ((f :: l -> Type) :.: (g :: k -> l)) (p :: k) = Comp (f (g p))
- unComp :: forall l k f (g :: k -> l) (p :: k). (f :.: g) p -> f (g p)
- mapII :: (a -> b) -> I a -> I b
- mapIK :: forall k a b (c :: k). (a -> b) -> I a -> K b c
- mapKI :: forall k a b (c :: k). (a -> b) -> K a c -> I b
- mapKK :: forall k1 k2 a b (c :: k1) (d :: k2). (a -> b) -> K a c -> K b d
- mapIII :: (a -> b -> c) -> I a -> I b -> I c
- mapIIK :: forall k a b c (d :: k). (a -> b -> c) -> I a -> I b -> K c d
- mapIKI :: forall k a b c (d :: k). (a -> b -> c) -> I a -> K b d -> I c
- mapIKK :: forall k1 k2 a b c (d :: k1) (e :: k2). (a -> b -> c) -> I a -> K b d -> K c e
- mapKII :: forall k a b c (d :: k). (a -> b -> c) -> K a d -> I b -> I c
- mapKIK :: forall k1 k2 a b c (d :: k1) (e :: k2). (a -> b -> c) -> K a d -> I b -> K c e
- mapKKI :: forall k1 k2 a b c (d :: k1) (e :: k2). (a -> b -> c) -> K a d -> K b e -> I c
- mapKKK :: forall k1 k2 k3 a b c (d :: k1) (e :: k2) (f :: k3). (a -> b -> c) -> K a d -> K b e -> K c f
- class (AllF c xs, SListI xs) => All (c :: k -> Constraint) (xs :: [k])
- type All2 (c :: k -> Constraint) = All (All c)
- cpara_SList :: All c xs => proxy c -> r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). (c y, All c ys) => r ys -> r (y ': ys)) -> r xs
- ccase_SList :: forall k c (xs :: [k]) proxy r. All c xs => proxy c -> r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). (c y, All c ys) => r (y ': ys)) -> r xs
- class (SListI xs, SListI ys, SameShapeAs xs ys, SameShapeAs ys xs, AllZipF c xs ys) => AllZip (c :: a -> b -> Constraint) (xs :: [a]) (ys :: [b])
- class (AllZipF (AllZip f) xss yss, SListI xss, SListI yss, SameShapeAs xss yss, SameShapeAs yss xss) => AllZip2 (f :: a -> b -> Constraint) (xss :: [[a]]) (yss :: [[b]])
- type family AllN (h :: (k -> Type) -> l -> Type) (c :: k -> Constraint) :: l -> Constraint
- type family AllZipN (h :: (k -> Type) -> l -> Type) (c :: k1 -> k2 -> Constraint) :: l1 -> l2 -> Constraint
- class f (g x) => Compose (f :: k -> Constraint) (g :: k1 -> k) (x :: k1)
- class (f x, g x) => And (f :: k -> Constraint) (g :: k -> Constraint) (x :: k)
- class Top (x :: k)
- class Coercible (f x) (g y) => LiftedCoercible (f :: k -> k1) (g :: k2 -> k1) (x :: k) (y :: k2)
- type family SameShapeAs (xs :: [a]) (ys :: [b]) where ...
- data SList (a :: [k]) where
- type SListI = All (Top :: k -> Constraint)
- type SListI2 = All (SListI :: [k] -> Constraint)
- sList :: forall k (xs :: [k]). SListI xs => SList xs
- para_SList :: forall k (xs :: [k]) r. SListI xs => r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). SListI ys => r ys -> r (y ': ys)) -> r xs
- case_SList :: forall k (xs :: [k]) r. SListI xs => r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). SListI ys => r (y ': ys)) -> r xs
- data Shape (a :: [k]) where
- shape :: forall k (xs :: [k]). SListI xs => Shape xs
- lengthSList :: forall k (xs :: [k]) proxy. SListI xs => proxy xs -> Int
- data Proxy (t :: k) = Proxy
Codes and interpretations
class All SListI (Code a) => Generic (a :: Type) where Source #
The class of representable datatypes.
The SOP approach to generic programming is based on viewing
datatypes as a representation (Rep
) built from the sum of
products of its components. The components of a datatype
are specified using the Code
type family.
The isomorphism between the original Haskell datatype and its
representation is witnessed by the methods of this class,
from
and to
. So for instances of this class, the following
laws should (in general) hold:
to
.
from
===id
:: a -> afrom
.
to
===id
::Rep
a ->Rep
a
You typically don't define instances of this class by hand, but rather derive the class instance automatically.
Option 1: Derive via the built-in GHC-generics. For this, you
need to use the DeriveGeneric
extension to first derive an
instance of the Generic
class from module GHC.Generics.
With this, you can then give an empty instance for Generic
, and
the default definitions will just work. The pattern looks as
follows:
import qualified GHC.Generics as GHC import Generics.SOP ... data T = ... deriving (GHC.Generic
, ...) instanceGeneric
T -- empty instanceHasDatatypeInfo
T -- empty, if you want/need metadata
Option 2: Derive via Template Haskell. For this, you need to
enable the TemplateHaskell
extension. You can then use
deriveGeneric
from module Generics.SOP.TH
to have the instance generated for you. The pattern looks as
follows:
import Generics.SOP import Generics.SOP.TH ... data T = ...deriveGeneric
''T -- derivesHasDatatypeInfo
as well
Tradeoffs: Whether to use Option 1 or 2 is mainly a matter of personal taste. The version based on Template Haskell probably has less run-time overhead.
Non-standard instances:
It is possible to give Generic
instances manually that deviate
from the standard scheme, as long as at least
to
.
from
===id
:: a -> a
still holds.
Nothing
type Code a :: [[Type]] Source #
The code of a datatype.
This is a list of lists of its components. The outer list contains one element per constructor. The inner list contains one element per constructor argument (field).
Example: The datatype
data Tree = Leaf Int | Node Tree Tree
is supposed to have the following code:
type instance Code (Tree a) = '[ '[ Int ] , '[ Tree, Tree ] ]
Converts from a value to its structural representation.
Converts from a structural representation back to the original value.
Instances
type IsProductType (a :: Type) (xs :: [Type]) = (Generic a, Code a ~ '[xs]) Source #
Constraint that captures that a datatype is a product type, i.e., a type with a single constructor.
It also gives access to the code for the arguments of that constructor.
Since: 0.3.1.0
type ProductCode (a :: Type) = Head (Code a) Source #
Direct access to the part of the code that is relevant for a product type.
Since: 0.4.0.0
productTypeFrom :: IsProductType a xs => a -> NP I xs Source #
Convert from a product type to its product representation.
Since: 0.4.0.0
productTypeTo :: IsProductType a xs => NP I xs -> a Source #
Convert a product representation to the original type.
Since: 0.4.0.0
type IsEnumType (a :: Type) = (Generic a, All ((~) '[]) (Code a)) Source #
Constraint that captures that a datatype is an enumeration type, i.e., none of the constructors have any arguments.
Since: 0.3.1.0
enumTypeFrom :: IsEnumType a => a -> NS (K ()) (Code a) Source #
Convert from an enum type to its sum representation.
Since: 0.4.0.0
enumTypeTo :: IsEnumType a => NS (K ()) (Code a) -> a Source #
Convert a sum representation to ihe original type.
type IsWrappedType (a :: Type) (x :: Type) = (Generic a, Code a ~ '['[x]]) Source #
Constraint that captures that a datatype is a single-constructor, single-field datatype. This always holds for newtype-defined types, but it can also be true for data-defined types.
The constraint also gives access to the type that is wrapped.
Since: 0.3.1.0
type WrappedCode (a :: Type) = Head (Head (Code a)) Source #
Direct access to the part of the code that is relevant for wrapped types and newtypes.
Since: 0.4.0.0
wrappedTypeFrom :: IsWrappedType a x => a -> x Source #
Convert from a wrapped type to its inner type.
Since: 0.4.0.0
wrappedTypeTo :: IsWrappedType a x => x -> a Source #
Convert a type to a wrapped type.
Since: 0.4.0.0
type IsNewtype (a :: Type) (x :: Type) = (IsWrappedType a x, Coercible a x) Source #
Constraint that captures that a datatype is a newtype. This makes use of the fact that newtypes are always coercible to the type they wrap, whereas datatypes are not.
Since: 0.3.1.0
newtypeFrom :: IsNewtype a x => a -> x Source #
n-ary datatypes
data NP (a :: k -> Type) (b :: [k]) where #
Nil :: forall k (a :: k -> Type). NP a ('[] :: [k]) | |
(:*) :: forall k (a :: k -> Type) (x :: k) (xs :: [k]). a x -> NP a xs -> NP a (x ': xs) |
Instances
HTrans (NP :: (k1 -> Type) -> [k1] -> Type) (NP :: (k2 -> Type) -> [k2] -> Type) | |
Defined in Data.SOP.NP htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod NP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> NP f xs -> NP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod NP) (LiftedCoercible f g) xs ys, HTrans NP NP) => NP f xs -> NP g ys # | |
HAp (NP :: (k -> Type) -> [k] -> Type) | |
HCollapse (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP | |
HPure (NP :: (k -> Type) -> [k] -> Type) | |
HSequence (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN NP xs, Applicative f) => NP (f :.: g) xs -> f (NP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN NP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> NP f xs -> g (NP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN NP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> NP f xs -> g (NP f' xs) # | |
HTraverse_ (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP hctraverse_ :: forall c (xs :: l) g proxy f. (AllN NP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> NP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN NP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> NP f xs -> g () # | |
All (Compose Eq f) xs => Eq (NP f xs) | |
(All (Compose Eq f) xs, All (Compose Ord f) xs) => Ord (NP f xs) | |
All (Compose Show f) xs => Show (NP f xs) | |
All (Compose Semigroup f) xs => Semigroup (NP f xs) | |
(All (Compose Monoid f) xs, All (Compose Semigroup f) xs) => Monoid (NP f xs) | |
All (Compose NFData f) xs => NFData (NP f xs) | |
Defined in Data.SOP.NP | |
type AllZipN (NP :: (k -> Type) -> [k] -> Type) (c :: a -> b -> Constraint) | |
Defined in Data.SOP.NP | |
type Same (NP :: (k1 -> Type) -> [k1] -> Type) | |
type Prod (NP :: (k -> Type) -> [k] -> Type) | |
type UnProd (NP :: (k -> Type) -> [k] -> Type) | |
type SListIN (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP | |
type CollapseTo (NP :: (k -> Type) -> [k] -> Type) a | |
Defined in Data.SOP.NP | |
type AllN (NP :: (k -> Type) -> [k] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NP |
data NS (a :: k -> Type) (b :: [k]) where #
Z :: forall k (a :: k -> Type) (x :: k) (xs :: [k]). a x -> NS a (x ': xs) | |
S :: forall k (a :: k -> Type) (xs :: [k]) (x :: k). NS a xs -> NS a (x ': xs) |
Instances
HTrans (NS :: (k1 -> Type) -> [k1] -> Type) (NS :: (k2 -> Type) -> [k2] -> Type) | |
Defined in Data.SOP.NS htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod NS) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> NS f xs -> NS g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod NS) (LiftedCoercible f g) xs ys, HTrans NS NS) => NS f xs -> NS g ys # | |
HAp (NS :: (k -> Type) -> [k] -> Type) | |
HApInjs (NS :: (k -> Type) -> [k] -> Type) | |
HCollapse (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS | |
HExpand (NS :: (k -> Type) -> [k] -> Type) | |
HIndex (NS :: (k -> Type) -> [k] -> Type) | |
HSequence (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN NS xs, Applicative f) => NS (f :.: g) xs -> f (NS g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN NS c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> NS f xs -> g (NS f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN NS xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> NS f xs -> g (NS f' xs) # | |
HTraverse_ (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS hctraverse_ :: forall c (xs :: l) g proxy f. (AllN NS c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> NS f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN NS xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> NS f xs -> g () # | |
All (Compose Eq f) xs => Eq (NS f xs) | |
(All (Compose Eq f) xs, All (Compose Ord f) xs) => Ord (NS f xs) | |
All (Compose Show f) xs => Show (NS f xs) | |
All (Compose NFData f) xs => NFData (NS f xs) | |
Defined in Data.SOP.NS | |
type Same (NS :: (k1 -> Type) -> [k1] -> Type) | |
type Prod (NS :: (k -> Type) -> [k] -> Type) | |
type SListIN (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS | |
type CollapseTo (NS :: (k -> Type) -> [k] -> Type) a | |
Defined in Data.SOP.NS | |
type AllN (NS :: (k -> Type) -> [k] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NS |
newtype SOP (f :: k -> Type) (xss :: [[k]]) #
Instances
HTrans (SOP :: (k1 -> Type) -> [[k1]] -> Type) (SOP :: (k2 -> Type) -> [[k2]] -> Type) | |
Defined in Data.SOP.NS htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod SOP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> SOP f xs -> SOP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod SOP) (LiftedCoercible f g) xs ys, HTrans SOP SOP) => SOP f xs -> SOP g ys # | |
HAp (SOP :: (k -> Type) -> [[k]] -> Type) | |
HApInjs (SOP :: (k -> Type) -> [[k]] -> Type) | |
HCollapse (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS | |
HExpand (SOP :: (k -> Type) -> [[k]] -> Type) | |
HIndex (SOP :: (k -> Type) -> [[k]] -> Type) | |
HSequence (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN SOP xs, Applicative f) => SOP (f :.: g) xs -> f (SOP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN SOP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> SOP f xs -> g (SOP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN SOP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> SOP f xs -> g (SOP f' xs) # | |
HTraverse_ (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS hctraverse_ :: forall c (xs :: l) g proxy f. (AllN SOP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> SOP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN SOP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> SOP f xs -> g () # | |
Eq (NS (NP f) xss) => Eq (SOP f xss) | |
Ord (NS (NP f) xss) => Ord (SOP f xss) | |
Defined in Data.SOP.NS | |
Show (NS (NP f) xss) => Show (SOP f xss) | |
NFData (NS (NP f) xss) => NFData (SOP f xss) | |
Defined in Data.SOP.NS | |
type Same (SOP :: (k1 -> Type) -> [[k1]] -> Type) | |
type Prod (SOP :: (k -> Type) -> [[k]] -> Type) | |
type SListIN (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS | |
type CollapseTo (SOP :: (k -> Type) -> [[k]] -> Type) a | |
Defined in Data.SOP.NS | |
type AllN (SOP :: (k -> Type) -> [[k]] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NS |
newtype POP (f :: k -> Type) (xss :: [[k]]) #
Instances
HTrans (POP :: (k1 -> Type) -> [[k1]] -> Type) (POP :: (k2 -> Type) -> [[k2]] -> Type) | |
Defined in Data.SOP.NP htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod POP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> POP f xs -> POP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod POP) (LiftedCoercible f g) xs ys, HTrans POP POP) => POP f xs -> POP g ys # | |
HAp (POP :: (k -> Type) -> [[k]] -> Type) | |
HCollapse (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP | |
HPure (POP :: (k -> Type) -> [[k]] -> Type) | |
HSequence (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN POP xs, Applicative f) => POP (f :.: g) xs -> f (POP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN POP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> POP f xs -> g (POP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN POP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> POP f xs -> g (POP f' xs) # | |
HTraverse_ (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP hctraverse_ :: forall c (xs :: l) g proxy f. (AllN POP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> POP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN POP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> POP f xs -> g () # | |
Eq (NP (NP f) xss) => Eq (POP f xss) | |
Ord (NP (NP f) xss) => Ord (POP f xss) | |
Defined in Data.SOP.NP | |
Show (NP (NP f) xss) => Show (POP f xss) | |
Semigroup (NP (NP f) xss) => Semigroup (POP f xss) | |
Monoid (NP (NP f) xss) => Monoid (POP f xss) | |
NFData (NP (NP f) xss) => NFData (POP f xss) | |
Defined in Data.SOP.NP | |
type AllZipN (POP :: (k -> Type) -> [[k]] -> Type) (c :: a -> b -> Constraint) | |
Defined in Data.SOP.NP | |
type Same (POP :: (k1 -> Type) -> [[k1]] -> Type) | |
type Prod (POP :: (k -> Type) -> [[k]] -> Type) | |
type UnProd (POP :: (k -> Type) -> [[k]] -> Type) | |
type SListIN (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP | |
type CollapseTo (POP :: (k -> Type) -> [[k]] -> Type) a | |
Defined in Data.SOP.NP | |
type AllN (POP :: (k -> Type) -> [[k]] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NP |
Metadata
data DatatypeInfo :: [[Type]] -> Type where Source #
Metadata for a datatype.
A value of type
contains the information about a datatype
that is not contained in DatatypeInfo
c
. This information consists
primarily of the names of the datatype, its constructors, and possibly its
record selectors.Code
c
The constructor indicates whether the datatype has been declared using newtype
or not.
ADT :: ModuleName -> DatatypeName -> NP ConstructorInfo xss -> POP StrictnessInfo xss -> DatatypeInfo xss | |
Newtype :: ModuleName -> DatatypeName -> ConstructorInfo '[x] -> DatatypeInfo '['[x]] |
Instances
moduleName :: DatatypeInfo xss -> ModuleName Source #
The module name where a datatype is defined.
Since: 0.2.3.0
datatypeName :: DatatypeInfo xss -> DatatypeName Source #
The name of a datatype (or newtype).
Since: 0.2.3.0
constructorInfo :: DatatypeInfo xss -> NP ConstructorInfo xss Source #
The constructor info for a datatype (or newtype).
Since: 0.2.3.0
data ConstructorInfo :: [Type] -> Type where Source #
Metadata for a single constructor.
This is indexed by the product structure of the constructor components.
Constructor :: SListI xs => ConstructorName -> ConstructorInfo xs | |
Infix :: ConstructorName -> Associativity -> Fixity -> ConstructorInfo '[x, y] | |
Record :: SListI xs => ConstructorName -> NP FieldInfo xs -> ConstructorInfo xs |
Instances
constructorName :: ConstructorInfo xs -> ConstructorName Source #
The name of a constructor.
Since: 0.2.3.0
data FieldInfo :: Type -> Type where Source #
For records, this functor maps the component to its selector name.
Instances
Functor FieldInfo Source # | |
Eq (FieldInfo a) Source # | |
Ord (FieldInfo a) Source # | |
Defined in Generics.SOP.Metadata | |
Show (FieldInfo a) Source # | |
class Generic a => HasDatatypeInfo a where Source #
A class of datatypes that have associated metadata.
It is possible to use the sum-of-products approach to generic programming without metadata. If you need metadata in a function, an additional constraint on this class is in order.
You typically don't define instances of this class by hand, but
rather derive the class instance automatically. See the documentation
of Generic
for the options.
Nothing
type DatatypeInfoOf a :: DatatypeInfo Source #
Type-level datatype info
type DatatypeInfoOf a = GDatatypeInfoOf a Source #
datatypeInfo :: proxy a -> DatatypeInfo (Code a) Source #
Term-level datatype info; by default, the term-level datatype info is produced from the type-level info.
default datatypeInfo :: (GDatatypeInfo a, GCode a ~ Code a) => proxy a -> DatatypeInfo (Code a) Source #
Instances
type DatatypeName = String Source #
The name of a datatype.
type ModuleName = String Source #
The name of a module.
type ConstructorName = String Source #
The name of a data constructor.
data Associativity #
Datatype to represent the associativity of a constructor
Instances
Combinators
Constructing products
class HPure (h :: (k -> Type) -> l -> Type) where #
hpure :: forall (xs :: l) f. SListIN h xs => (forall (a :: k). f a) -> h f xs #
hcpure :: forall c (xs :: l) proxy f. AllN h c xs => proxy c -> (forall (a :: k). c a => f a) -> h f xs #
Destructing products
projections :: forall k (xs :: [k]) (f :: k -> Type). SListI xs => NP (Projection f xs) xs #
shiftProjection :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Projection f xs a2 -> Projection f (x ': xs) a2 #
Application
newtype ((f :: k -> Type) -.-> (g :: k -> Type)) (a :: k) #
Instances
HasDatatypeInfo ((f -.-> g) a) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf ((f -.-> g) a) :: DatatypeInfo Source # datatypeInfo :: proxy ((f -.-> g) a) -> DatatypeInfo (Code ((f -.-> g) a)) Source # | |
Generic ((f -.-> g) a) Source # | |
type DatatypeInfoOf ((f -.-> g) a) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf ((f -.-> g) a) = 'Newtype "Data.SOP.Classes" "-.->" ('Record "Fn" '['FieldInfo "apFn"]) | |
type Code ((f -.-> g) a) Source # | |
Defined in Generics.SOP.Instances |
fn_3 :: forall k f (a :: k) f' f'' f'''. (f a -> f' a -> f'' a -> f''' a) -> (f -.-> (f' -.-> (f'' -.-> f'''))) a #
fn_4 :: forall k f (a :: k) f' f'' f''' f''''. (f a -> f' a -> f'' a -> f''' a -> f'''' a) -> (f -.-> (f' -.-> (f'' -.-> (f''' -.-> f'''')))) a #
type family Prod (h :: (k -> Type) -> l -> Type) :: (k -> Type) -> l -> Type #
class (Prod (Prod h) ~ Prod h, HPure (Prod h)) => HAp (h :: (k -> Type) -> l -> Type) where #
hap :: forall (f :: k -> Type) (g :: k -> Type) (xs :: l). Prod h (f -.-> g) xs -> h f xs -> h g xs #
Lifting / mapping
hliftA :: forall k l h (xs :: l) f f'. (SListIN (Prod h) xs, HAp h) => (forall (a :: k). f a -> f' a) -> h f xs -> h f' xs #
hliftA2 :: forall k l h (xs :: l) f f' f''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs #
hliftA3 :: forall k l h (xs :: l) f f' f'' f'''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs #
hcliftA :: forall k l h c (xs :: l) proxy f f'. (AllN (Prod h) c xs, HAp h) => proxy c -> (forall (a :: k). c a => f a -> f' a) -> h f xs -> h f' xs #
hcliftA2 :: forall k l h c (xs :: l) proxy f f' f''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs #
hcliftA3 :: forall k l h c (xs :: l) proxy f f' f'' f'''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs #
hmap :: forall k l h (xs :: l) f f'. (SListIN (Prod h) xs, HAp h) => (forall (a :: k). f a -> f' a) -> h f xs -> h f' xs #
hzipWith :: forall k l h (xs :: l) f f' f''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs #
hzipWith3 :: forall k l h (xs :: l) f f' f'' f'''. (SListIN (Prod h) xs, HAp h, HAp (Prod h)) => (forall (a :: k). f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs #
hcmap :: forall k l h c (xs :: l) proxy f f'. (AllN (Prod h) c xs, HAp h) => proxy c -> (forall (a :: k). c a => f a -> f' a) -> h f xs -> h f' xs #
hczipWith :: forall k l h c (xs :: l) proxy f f' f''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a) -> Prod h f xs -> h f' xs -> h f'' xs #
hczipWith3 :: forall k l h c (xs :: l) proxy f f' f'' f'''. (AllN (Prod h) c xs, HAp h, HAp (Prod h)) => proxy c -> (forall (a :: k). c a => f a -> f' a -> f'' a -> f''' a) -> Prod h f xs -> Prod h f' xs -> h f'' xs -> h f''' xs #
Constructing sums
shift :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Injection f xs a2 -> Injection f (x ': xs) a2 #
shiftInjection :: forall a1 (f :: a1 -> Type) (xs :: [a1]) (a2 :: a1) (x :: a1). Injection f xs a2 -> Injection f (x ': xs) a2 #
type family UnProd (h :: (k -> Type) -> l -> Type) :: (k -> Type) -> l -> Type #
class UnProd (Prod h) ~ h => HApInjs (h :: (k -> Type) -> l -> Type) where #
Destructing sums
shiftEjection :: forall a1 (f :: a1 -> Type) (x :: a1) (xs :: [a1]) (a2 :: a1). Ejection f xs a2 -> Ejection f (x ': xs) a2 #
Dealing with All
c
All
chcliftA' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f'. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs) -> h f xss -> h f' xss #
hcliftA2' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f' f''. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs -> f'' xs) -> Prod h f xss -> h f' xss -> h f'' xss #
hcliftA3' :: forall k (c :: k -> Constraint) (xss :: [[k]]) h proxy f f' f'' f'''. (All2 c xss, Prod h ~ (NP :: ([k] -> Type) -> [[k]] -> Type), HAp h) => proxy c -> (forall (xs :: [k]). All c xs => f xs -> f' xs -> f'' xs -> f''' xs) -> Prod h f xss -> Prod h f' xss -> h f'' xss -> h f''' xss #
Comparison
compare_NS :: forall k r f g (xs :: [k]). r -> (forall (x :: k). f x -> g x -> r) -> r -> NS f xs -> NS g xs -> r #
ccompare_NS :: forall k c proxy r f g (xs :: [k]). All c xs => proxy c -> r -> (forall (x :: k). c x => f x -> g x -> r) -> r -> NS f xs -> NS g xs -> r #
compare_SOP :: forall k r (f :: k -> Type) (g :: k -> Type) (xss :: [[k]]). r -> (forall (xs :: [k]). NP f xs -> NP g xs -> r) -> r -> SOP f xss -> SOP g xss -> r #
ccompare_SOP :: forall k (c :: k -> Constraint) proxy r (f :: k -> Type) (g :: k -> Type) (xss :: [[k]]). All2 c xss => proxy c -> r -> (forall (xs :: [k]). All c xs => NP f xs -> NP g xs -> r) -> r -> SOP f xss -> SOP g xss -> r #
Collapsing
type family CollapseTo (h :: (k -> Type) -> l -> Type) x #
Instances
type CollapseTo (NS :: (k -> Type) -> [k] -> Type) a | |
Defined in Data.SOP.NS | |
type CollapseTo (SOP :: (k -> Type) -> [[k]] -> Type) a | |
Defined in Data.SOP.NS | |
type CollapseTo (NP :: (k -> Type) -> [k] -> Type) a | |
Defined in Data.SOP.NP | |
type CollapseTo (POP :: (k -> Type) -> [[k]] -> Type) a | |
Defined in Data.SOP.NP |
class HCollapse (h :: (k -> Type) -> l -> Type) where #
hcollapse :: forall (xs :: l) a. SListIN h xs => h (K a :: k -> Type) xs -> CollapseTo h a #
Instances
HCollapse (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS | |
HCollapse (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS | |
HCollapse (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP | |
HCollapse (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP |
Folding and sequencing
class HTraverse_ (h :: (k -> Type) -> l -> Type) where #
hctraverse_ :: forall c (xs :: l) g proxy f. (AllN h c xs, Applicative g) => proxy c -> (forall (a :: k). c a => f a -> g ()) -> h f xs -> g () #
htraverse_ :: forall (xs :: l) g f. (SListIN h xs, Applicative g) => (forall (a :: k). f a -> g ()) -> h f xs -> g () #
Instances
HTraverse_ (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS hctraverse_ :: forall c (xs :: l) g proxy f. (AllN SOP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> SOP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN SOP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> SOP f xs -> g () # | |
HTraverse_ (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS hctraverse_ :: forall c (xs :: l) g proxy f. (AllN NS c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> NS f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN NS xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> NS f xs -> g () # | |
HTraverse_ (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP hctraverse_ :: forall c (xs :: l) g proxy f. (AllN POP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> POP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN POP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> POP f xs -> g () # | |
HTraverse_ (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP hctraverse_ :: forall c (xs :: l) g proxy f. (AllN NP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g ()) -> NP f xs -> g () # htraverse_ :: forall (xs :: l) g f. (SListIN NP xs, Applicative g) => (forall (a :: k0). f a -> g ()) -> NP f xs -> g () # |
hcfoldMap :: forall k l h c (xs :: l) m proxy f. (HTraverse_ h, AllN h c xs, Monoid m) => proxy c -> (forall (a :: k). c a => f a -> m) -> h f xs -> m #
hcfor_ :: forall k l h c (xs :: l) g proxy f. (HTraverse_ h, AllN h c xs, Applicative g) => proxy c -> h f xs -> (forall (a :: k). c a => f a -> g ()) -> g () #
class HAp h => HSequence (h :: (k -> Type) -> l -> Type) where #
hsequence' :: forall (xs :: l) f (g :: k -> Type). (SListIN h xs, Applicative f) => h (f :.: g) xs -> f (h g xs) #
hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN h c xs, Applicative g) => proxy c -> (forall (a :: k). c a => f a -> g (f' a)) -> h f xs -> g (h f' xs) #
htraverse' :: forall (xs :: l) g f f'. (SListIN h xs, Applicative g) => (forall (a :: k). f a -> g (f' a)) -> h f xs -> g (h f' xs) #
Instances
HSequence (SOP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NS hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN SOP xs, Applicative f) => SOP (f :.: g) xs -> f (SOP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN SOP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> SOP f xs -> g (SOP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN SOP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> SOP f xs -> g (SOP f' xs) # | |
HSequence (NS :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NS hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN NS xs, Applicative f) => NS (f :.: g) xs -> f (NS g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN NS c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> NS f xs -> g (NS f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN NS xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> NS f xs -> g (NS f' xs) # | |
HSequence (POP :: (k -> Type) -> [[k]] -> Type) | |
Defined in Data.SOP.NP hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN POP xs, Applicative f) => POP (f :.: g) xs -> f (POP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN POP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> POP f xs -> g (POP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN POP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> POP f xs -> g (POP f' xs) # | |
HSequence (NP :: (k -> Type) -> [k] -> Type) | |
Defined in Data.SOP.NP hsequence' :: forall (xs :: l) f (g :: k0 -> Type). (SListIN NP xs, Applicative f) => NP (f :.: g) xs -> f (NP g xs) # hctraverse' :: forall c (xs :: l) g proxy f f'. (AllN NP c xs, Applicative g) => proxy c -> (forall (a :: k0). c a => f a -> g (f' a)) -> NP f xs -> g (NP f' xs) # htraverse' :: forall (xs :: l) g f f'. (SListIN NP xs, Applicative g) => (forall (a :: k0). f a -> g (f' a)) -> NP f xs -> g (NP f' xs) # |
hsequence :: forall l h (xs :: l) f. (SListIN h xs, SListIN (Prod h) xs, HSequence h, Applicative f) => h f xs -> f (h I xs) #
hsequenceK :: forall k l h (xs :: l) f a. (SListIN h xs, SListIN (Prod h) xs, Applicative f, HSequence h) => h (K (f a) :: k -> Type) xs -> f (h (K a :: k -> Type) xs) #
hctraverse :: forall l h c (xs :: l) g proxy f. (HSequence h, AllN h c xs, Applicative g) => proxy c -> (forall a. c a => f a -> g a) -> h f xs -> g (h I xs) #
hcfor :: forall l h c (xs :: l) g proxy f. (HSequence h, AllN h c xs, Applicative g) => proxy c -> h f xs -> (forall a. c a => f a -> g a) -> g (h I xs) #
Expanding sums to products
class HExpand (h :: (k -> Type) -> l -> Type) where #
hexpand :: forall (xs :: l) f. SListIN (Prod h) xs => (forall (x :: k). f x) -> h f xs -> Prod h f xs #
hcexpand :: forall c (xs :: l) proxy f. AllN (Prod h) c xs => proxy c -> (forall (x :: k). c x => f x) -> h f xs -> Prod h f xs #
Transformation of index lists and coercions
class ((Same h1 :: (k2 -> Type) -> l2 -> Type) ~ h2, (Same h2 :: (k1 -> Type) -> l1 -> Type) ~ h1) => HTrans (h1 :: (k1 -> Type) -> l1 -> Type) (h2 :: (k2 -> Type) -> l2 -> Type) where #
htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod h1) c xs ys => proxy c -> (forall (x :: k1) (y :: k2). c x y => f x -> g y) -> h1 f xs -> h2 g ys #
hcoerce :: forall (f :: k1 -> Type) (g :: k2 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod h1) (LiftedCoercible f g) xs ys, HTrans h1 h2) => h1 f xs -> h2 g ys #
Instances
HTrans (SOP :: (k1 -> Type) -> [[k1]] -> Type) (SOP :: (k2 -> Type) -> [[k2]] -> Type) | |
Defined in Data.SOP.NS htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod SOP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> SOP f xs -> SOP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod SOP) (LiftedCoercible f g) xs ys, HTrans SOP SOP) => SOP f xs -> SOP g ys # | |
HTrans (NS :: (k1 -> Type) -> [k1] -> Type) (NS :: (k2 -> Type) -> [k2] -> Type) | |
Defined in Data.SOP.NS htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod NS) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> NS f xs -> NS g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod NS) (LiftedCoercible f g) xs ys, HTrans NS NS) => NS f xs -> NS g ys # | |
HTrans (POP :: (k1 -> Type) -> [[k1]] -> Type) (POP :: (k2 -> Type) -> [[k2]] -> Type) | |
Defined in Data.SOP.NP htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod POP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> POP f xs -> POP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod POP) (LiftedCoercible f g) xs ys, HTrans POP POP) => POP f xs -> POP g ys # | |
HTrans (NP :: (k1 -> Type) -> [k1] -> Type) (NP :: (k2 -> Type) -> [k2] -> Type) | |
Defined in Data.SOP.NP htrans :: forall c (xs :: l1) (ys :: l2) proxy f g. AllZipN (Prod NP) c xs ys => proxy c -> (forall (x :: k10) (y :: k20). c x y => f x -> g y) -> NP f xs -> NP g ys # hcoerce :: forall (f :: k10 -> Type) (g :: k20 -> Type) (xs :: l1) (ys :: l2). (AllZipN (Prod NP) (LiftedCoercible f g) xs ys, HTrans NP NP) => NP f xs -> NP g ys # |
hfromI :: forall l1 k2 l2 h1 (f :: k2 -> Type) (xs :: l1) (ys :: l2) h2. (AllZipN (Prod h1) (LiftedCoercible I f) xs ys, HTrans h1 h2) => h1 I xs -> h2 f ys #
htoI :: forall k1 l1 l2 h1 (f :: k1 -> Type) (xs :: l1) (ys :: l2) h2. (AllZipN (Prod h1) (LiftedCoercible f I) xs ys, HTrans h1 h2) => h1 f xs -> h2 I ys #
Partial operations
Utilities
Basic functors
K a |
Instances
Eq2 (K :: Type -> Type -> Type) | |
Ord2 (K :: Type -> Type -> Type) | |
Defined in Data.SOP.BasicFunctors | |
Read2 (K :: Type -> Type -> Type) | |
Defined in Data.SOP.BasicFunctors liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (K a b) # liftReadList2 :: (Int -> ReadS a) -> ReadS [a] -> (Int -> ReadS b) -> ReadS [b] -> ReadS [K a b] # liftReadPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec (K a b) # liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] -> ReadPrec b -> ReadPrec [b] -> ReadPrec [K a b] # | |
Show2 (K :: Type -> Type -> Type) | |
NFData2 (K :: Type -> Type -> Type) | |
Defined in Data.SOP.BasicFunctors | |
Functor (K a :: Type -> Type) | |
Monoid a => Applicative (K a :: Type -> Type) | |
Foldable (K a :: Type -> Type) | |
Defined in Data.SOP.BasicFunctors fold :: Monoid m => K a m -> m # foldMap :: Monoid m => (a0 -> m) -> K a a0 -> m # foldMap' :: Monoid m => (a0 -> m) -> K a a0 -> m # foldr :: (a0 -> b -> b) -> b -> K a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> K a a0 -> b # foldl :: (b -> a0 -> b) -> b -> K a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> K a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> K a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> K a a0 -> a0 # elem :: Eq a0 => a0 -> K a a0 -> Bool # maximum :: Ord a0 => K a a0 -> a0 # minimum :: Ord a0 => K a a0 -> a0 # | |
Traversable (K a :: Type -> Type) | |
Eq a => Eq1 (K a :: Type -> Type) | |
Ord a => Ord1 (K a :: Type -> Type) | |
Defined in Data.SOP.BasicFunctors | |
Read a => Read1 (K a :: Type -> Type) | |
Defined in Data.SOP.BasicFunctors | |
Show a => Show1 (K a :: Type -> Type) | |
NFData a => NFData1 (K a :: Type -> Type) | |
Defined in Data.SOP.BasicFunctors | |
Eq a => Eq (K a b) | |
Ord a => Ord (K a b) | |
Read a => Read (K a b) | |
Show a => Show (K a b) | |
Generic (K a b) | |
Semigroup a => Semigroup (K a b) | |
Monoid a => Monoid (K a b) | |
NFData a => NFData (K a b) | |
Defined in Data.SOP.BasicFunctors | |
HasDatatypeInfo (K a b) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf (K a b) :: DatatypeInfo Source # datatypeInfo :: proxy (K a b) -> DatatypeInfo (Code (K a b)) Source # | |
Generic (K a b) Source # | |
type Rep (K a b) | |
Defined in Data.SOP.BasicFunctors | |
type DatatypeInfoOf (K a b) Source # | |
Defined in Generics.SOP.Instances | |
type Code (K a b) Source # | |
Defined in Generics.SOP.Instances |
I a |
Instances
Monad I | |
Functor I | |
Applicative I | |
Foldable I | |
Defined in Data.SOP.BasicFunctors fold :: Monoid m => I m -> m # foldMap :: Monoid m => (a -> m) -> I a -> m # foldMap' :: Monoid m => (a -> m) -> I a -> m # foldr :: (a -> b -> b) -> b -> I a -> b # foldr' :: (a -> b -> b) -> b -> I a -> b # foldl :: (b -> a -> b) -> b -> I a -> b # foldl' :: (b -> a -> b) -> b -> I a -> b # foldr1 :: (a -> a -> a) -> I a -> a # foldl1 :: (a -> a -> a) -> I a -> a # elem :: Eq a => a -> I a -> Bool # maximum :: Ord a => I a -> a # | |
Traversable I | |
Eq1 I | |
Ord1 I | |
Defined in Data.SOP.BasicFunctors | |
Read1 I | |
Show1 I | |
NFData1 I | |
Defined in Data.SOP.BasicFunctors | |
Eq a => Eq (I a) | |
Ord a => Ord (I a) | |
Read a => Read (I a) | |
Show a => Show (I a) | |
Generic (I a) | |
Semigroup a => Semigroup (I a) | |
Monoid a => Monoid (I a) | |
NFData a => NFData (I a) | |
Defined in Data.SOP.BasicFunctors | |
HasDatatypeInfo (I a) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf (I a) :: DatatypeInfo Source # datatypeInfo :: proxy (I a) -> DatatypeInfo (Code (I a)) Source # | |
Generic (I a) Source # | |
type Rep (I a) | |
Defined in Data.SOP.BasicFunctors | |
type DatatypeInfoOf (I a) Source # | |
Defined in Generics.SOP.Instances | |
type Code (I a) Source # | |
Defined in Generics.SOP.Instances |
newtype ((f :: l -> Type) :.: (g :: k -> l)) (p :: k) #
Comp (f (g p)) |
Instances
(Functor f, Functor g) => Functor (f :.: g) | |
(Applicative f, Applicative g) => Applicative (f :.: g) | |
(Foldable f, Foldable g) => Foldable (f :.: g) | |
Defined in Data.SOP.BasicFunctors fold :: Monoid m => (f :.: g) m -> m # foldMap :: Monoid m => (a -> m) -> (f :.: g) a -> m # foldMap' :: Monoid m => (a -> m) -> (f :.: g) a -> m # foldr :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldr' :: (a -> b -> b) -> b -> (f :.: g) a -> b # foldl :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldl' :: (b -> a -> b) -> b -> (f :.: g) a -> b # foldr1 :: (a -> a -> a) -> (f :.: g) a -> a # foldl1 :: (a -> a -> a) -> (f :.: g) a -> a # toList :: (f :.: g) a -> [a] # length :: (f :.: g) a -> Int # elem :: Eq a => a -> (f :.: g) a -> Bool # maximum :: Ord a => (f :.: g) a -> a # minimum :: Ord a => (f :.: g) a -> a # | |
(Traversable f, Traversable g) => Traversable (f :.: g) | |
Defined in Data.SOP.BasicFunctors | |
(Eq1 f, Eq1 g) => Eq1 (f :.: g) | |
(Ord1 f, Ord1 g) => Ord1 (f :.: g) | |
Defined in Data.SOP.BasicFunctors | |
(Read1 f, Read1 g) => Read1 (f :.: g) | |
Defined in Data.SOP.BasicFunctors | |
(Show1 f, Show1 g) => Show1 (f :.: g) | |
(NFData1 f, NFData1 g) => NFData1 (f :.: g) | |
Defined in Data.SOP.BasicFunctors | |
(Eq1 f, Eq1 g, Eq a) => Eq ((f :.: g) a) | |
(Ord1 f, Ord1 g, Ord a) => Ord ((f :.: g) a) | |
Defined in Data.SOP.BasicFunctors | |
(Read1 f, Read1 g, Read a) => Read ((f :.: g) a) | |
(Show1 f, Show1 g, Show a) => Show ((f :.: g) a) | |
Generic ((f :.: g) p) | |
Semigroup (f (g x)) => Semigroup ((f :.: g) x) | |
Monoid (f (g x)) => Monoid ((f :.: g) x) | |
NFData (f (g a)) => NFData ((f :.: g) a) | |
Defined in Data.SOP.BasicFunctors | |
HasDatatypeInfo ((f :.: g) p) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf ((f :.: g) p) :: DatatypeInfo Source # datatypeInfo :: proxy ((f :.: g) p) -> DatatypeInfo (Code ((f :.: g) p)) Source # | |
Generic ((f :.: g) p) Source # | |
type Rep ((f :.: g) p) | |
Defined in Data.SOP.BasicFunctors | |
type DatatypeInfoOf ((f :.: g) p) Source # | |
Defined in Generics.SOP.Instances | |
type Code ((f :.: g) p) Source # | |
Defined in Generics.SOP.Instances |
Mapping functions
mapKKK :: forall k1 k2 k3 a b c (d :: k1) (e :: k2) (f :: k3). (a -> b -> c) -> K a d -> K b e -> K c f #
Mapping constraints
class (AllF c xs, SListI xs) => All (c :: k -> Constraint) (xs :: [k]) #
Instances
All (c :: k -> Constraint) ('[] :: [k]) | |
Defined in Data.SOP.Constraint cpara_SList :: proxy c -> r '[] -> (forall (y :: k0) (ys :: [k0]). (c y, All c ys) => r ys -> r (y ': ys)) -> r '[] # | |
(c x, All c xs) => All (c :: a -> Constraint) (x ': xs :: [a]) | |
Defined in Data.SOP.Constraint cpara_SList :: proxy c -> r '[] -> (forall (y :: k) (ys :: [k]). (c y, All c ys) => r ys -> r (y ': ys)) -> r (x ': xs) # |
type All2 (c :: k -> Constraint) = All (All c) #
cpara_SList :: All c xs => proxy c -> r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). (c y, All c ys) => r ys -> r (y ': ys)) -> r xs #
ccase_SList :: forall k c (xs :: [k]) proxy r. All c xs => proxy c -> r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). (c y, All c ys) => r (y ': ys)) -> r xs #
class (SListI xs, SListI ys, SameShapeAs xs ys, SameShapeAs ys xs, AllZipF c xs ys) => AllZip (c :: a -> b -> Constraint) (xs :: [a]) (ys :: [b]) #
Instances
(SListI xs, SListI ys, SameShapeAs xs ys, SameShapeAs ys xs, AllZipF c xs ys) => AllZip (c :: a -> b -> Constraint) (xs :: [a]) (ys :: [b]) | |
Defined in Data.SOP.Constraint |
class (AllZipF (AllZip f) xss yss, SListI xss, SListI yss, SameShapeAs xss yss, SameShapeAs yss xss) => AllZip2 (f :: a -> b -> Constraint) (xss :: [[a]]) (yss :: [[b]]) #
Instances
(AllZipF (AllZip f) xss yss, SListI xss, SListI yss, SameShapeAs xss yss, SameShapeAs yss xss) => AllZip2 (f :: a -> b -> Constraint) (xss :: [[a]]) (yss :: [[b]]) | |
Defined in Data.SOP.Constraint |
type family AllN (h :: (k -> Type) -> l -> Type) (c :: k -> Constraint) :: l -> Constraint #
Instances
type AllN (NS :: (k -> Type) -> [k] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NS | |
type AllN (SOP :: (k -> Type) -> [[k]] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NS | |
type AllN (NP :: (k -> Type) -> [k] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NP | |
type AllN (POP :: (k -> Type) -> [[k]] -> Type) (c :: k -> Constraint) | |
Defined in Data.SOP.NP |
type family AllZipN (h :: (k -> Type) -> l -> Type) (c :: k1 -> k2 -> Constraint) :: l1 -> l2 -> Constraint #
Instances
type AllZipN (NP :: (k -> Type) -> [k] -> Type) (c :: a -> b -> Constraint) | |
Defined in Data.SOP.NP | |
type AllZipN (POP :: (k -> Type) -> [[k]] -> Type) (c :: a -> b -> Constraint) | |
Defined in Data.SOP.NP |
Other constraints
class f (g x) => Compose (f :: k -> Constraint) (g :: k1 -> k) (x :: k1) #
Instances
f (g x) => Compose (f :: k1 -> Constraint) (g :: k2 -> k1) (x :: k2) | |
Defined in Data.SOP.Constraint |
class (f x, g x) => And (f :: k -> Constraint) (g :: k -> Constraint) (x :: k) #
Instances
(f x, g x) => And (f :: k -> Constraint) (g :: k -> Constraint) (x :: k) | |
Defined in Data.SOP.Constraint |
Instances
Top (x :: k) | |
Defined in Data.SOP.Constraint |
class Coercible (f x) (g y) => LiftedCoercible (f :: k -> k1) (g :: k2 -> k1) (x :: k) (y :: k2) #
Instances
Coercible (f x) (g y) => LiftedCoercible (f :: k1 -> k2) (g :: k3 -> k2) (x :: k1) (y :: k3) | |
Defined in Data.SOP.Constraint |
type family SameShapeAs (xs :: [a]) (ys :: [b]) where ... #
SameShapeAs ('[] :: [a]) (ys :: [b]) = ys ~ ('[] :: [b]) | |
SameShapeAs (x ': xs :: [a1]) (ys :: [a2]) = ys ~ (Head ys ': Tail ys) |
Singletons
SNil :: forall k. SList ('[] :: [k]) | |
SCons :: forall k (xs :: [k]) (x :: k). SListI xs => SList (x ': xs) |
type SListI = All (Top :: k -> Constraint) #
type SListI2 = All (SListI :: [k] -> Constraint) #
para_SList :: forall k (xs :: [k]) r. SListI xs => r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). SListI ys => r ys -> r (y ': ys)) -> r xs #
case_SList :: forall k (xs :: [k]) r. SListI xs => r ('[] :: [k]) -> (forall (y :: k) (ys :: [k]). SListI ys => r (y ': ys)) -> r xs #
Shape of type-level lists
ShapeNil :: forall k. Shape ('[] :: [k]) | |
ShapeCons :: forall k (xs :: [k]) (x :: k). SListI xs => Shape xs -> Shape (x ': xs) |
lengthSList :: forall k (xs :: [k]) proxy. SListI xs => proxy xs -> Int #
Re-exports
Proxy
is a type that holds no data, but has a phantom parameter of
arbitrary type (or even kind). Its use is to provide type information, even
though there is no value available of that type (or it may be too costly to
create one).
Historically,
is a safer alternative to the
Proxy
:: Proxy
a
idiom.undefined
:: a
>>>
Proxy :: Proxy (Void, Int -> Int)
Proxy
Proxy can even hold types of higher kinds,
>>>
Proxy :: Proxy Either
Proxy
>>>
Proxy :: Proxy Functor
Proxy
>>>
Proxy :: Proxy complicatedStructure
Proxy
Instances
Generic1 (Proxy :: k -> Type) | Since: base-4.6.0.0 |
Monad (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
Functor (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
Applicative (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
Foldable (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
Defined in Data.Foldable fold :: Monoid m => Proxy m -> m # foldMap :: Monoid m => (a -> m) -> Proxy a -> m # foldMap' :: Monoid m => (a -> m) -> Proxy a -> m # foldr :: (a -> b -> b) -> b -> Proxy a -> b # foldr' :: (a -> b -> b) -> b -> Proxy a -> b # foldl :: (b -> a -> b) -> b -> Proxy a -> b # foldl' :: (b -> a -> b) -> b -> Proxy a -> b # foldr1 :: (a -> a -> a) -> Proxy a -> a # foldl1 :: (a -> a -> a) -> Proxy a -> a # elem :: Eq a => a -> Proxy a -> Bool # maximum :: Ord a => Proxy a -> a # minimum :: Ord a => Proxy a -> a # | |
Traversable (Proxy :: Type -> Type) | Since: base-4.7.0.0 |
Alternative (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
MonadPlus (Proxy :: Type -> Type) | Since: base-4.9.0.0 |
Bounded (Proxy t) | Since: base-4.7.0.0 |
Enum (Proxy s) | Since: base-4.7.0.0 |
Eq (Proxy s) | Since: base-4.7.0.0 |
Data t => Data (Proxy t) | Since: base-4.7.0.0 |
Defined in Data.Data gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Proxy t -> c (Proxy t) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Proxy t) # toConstr :: Proxy t -> Constr # dataTypeOf :: Proxy t -> DataType # dataCast1 :: Typeable t0 => (forall d. Data d => c (t0 d)) -> Maybe (c (Proxy t)) # dataCast2 :: Typeable t0 => (forall d e. (Data d, Data e) => c (t0 d e)) -> Maybe (c (Proxy t)) # gmapT :: (forall b. Data b => b -> b) -> Proxy t -> Proxy t # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Proxy t -> r # gmapQ :: (forall d. Data d => d -> u) -> Proxy t -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Proxy t -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Proxy t -> m (Proxy t) # | |
Ord (Proxy s) | Since: base-4.7.0.0 |
Read (Proxy t) | Since: base-4.7.0.0 |
Show (Proxy s) | Since: base-4.7.0.0 |
Ix (Proxy s) | Since: base-4.7.0.0 |
Defined in Data.Proxy | |
Generic (Proxy t) | Since: base-4.6.0.0 |
Semigroup (Proxy s) | Since: base-4.9.0.0 |
Monoid (Proxy s) | Since: base-4.7.0.0 |
HasDatatypeInfo (Proxy t) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf (Proxy t) :: DatatypeInfo Source # datatypeInfo :: proxy (Proxy t) -> DatatypeInfo (Code (Proxy t)) Source # | |
Generic (Proxy t) Source # | |
type Rep1 (Proxy :: k -> Type) | |
type Rep (Proxy t) | |
type DatatypeInfoOf (Proxy t) Source # | |
Defined in Generics.SOP.Instances type DatatypeInfoOf (Proxy t) = 'ADT "Data.Proxy" "Proxy" '['Constructor "Proxy"] '['[] :: [StrictnessInfo]] | |
type Code (Proxy t) Source # | |
Defined in Generics.SOP.Instances |