Safe Haskell	None
Language	Haskell2010

Generics.SOP.Type.Metadata

Contents

re-exports

Description

Type-level metadata

This module provides datatypes (to be used promoted) that can represent the metadata of Haskell datatypes on the type level.

We do not reuse the term-level metadata types, because these are GADTs that incorporate additional invariants. We could (at least in GHC 8) impose the same invariants on the type level as well, but some tests have revealed that the resulting type are rather inconvenient to work with.

So we use simple datatypes to represent the type-level metadata, even if this means that some invariants are not explicitly captured.

We establish a relation between the term- and type-level versions of the metadata by automatically computing the term-level version from the type-level version.

As we now have two versions of metadata (term-level and type-level) with very similar, yet slightly different datatype definitions, the names between the modules clash, and this module is recommended to be imported qualified when needed.

The interface exported by this module is still somewhat experimental.

Since: 0.3.0.0

Synopsis

class DemoteAssociativity (a :: Associativity) where
class DemoteFieldInfo (x :: FieldInfo) (a :: *) where
class SListI xs => DemoteFieldInfos (fs :: [FieldInfo]) (xs :: [*]) where
class DemoteConstructorInfo (x :: ConstructorInfo) (xs :: [*]) where
class DemoteConstructorInfos (cs :: [ConstructorInfo]) (xss :: [[*]]) where
class DemoteDatatypeInfo (x :: DatatypeInfo) (xss :: [[*]]) where
type Fixity = Nat
type FieldName = Symbol
type ConstructorName = Symbol
type ModuleName = Symbol
type DatatypeName = Symbol
data FieldInfo = FieldInfo FieldName
data ConstructorInfo
data DatatypeInfo
- = ADT ModuleName DatatypeName [ConstructorInfo]
- | Newtype ModuleName DatatypeName ConstructorInfo
data Associativity
- = LeftAssociative
- | RightAssociative
- | NotAssociative

Documentation

class DemoteAssociativity (a :: Associativity) where Source #

Class for computing term-level associativity information from type-level associativity information.

Since: 0.3.0.0

Minimal complete definition

demoteAssociativity

Methods

demoteAssociativity :: proxy a -> Associativity Source #

Given a proxy of some type-level associativity information, return the corresponding term-level information.

Since: 0.3.0.0

Instances

DemoteAssociativity LeftAssociative Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteAssociativity :: proxy LeftAssociative -> Associativity Source #
DemoteAssociativity RightAssociative Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteAssociativity :: proxy RightAssociative -> Associativity Source #
DemoteAssociativity NotAssociative Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteAssociativity :: proxy NotAssociative -> Associativity Source #

class DemoteFieldInfo (x :: FieldInfo) (a :: *) where Source #

Class for computing term-level field information from type-level field information.

Since: 0.3.0.0

Minimal complete definition

demoteFieldInfo

Methods

demoteFieldInfo :: proxy x -> FieldInfo a Source #

Given a proxy of some type-level field information, return the corresponding term-level information.

Since: 0.3.0.0

Instances

KnownSymbol s => DemoteFieldInfo (FieldInfo s) a Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteFieldInfo :: proxy (FieldInfo s) -> FieldInfo0 a Source #

class SListI xs => DemoteFieldInfos (fs :: [FieldInfo]) (xs :: [*]) where Source #

Class for computing term-level field information from type-level field information.

Since: 0.3.0.0

Minimal complete definition

demoteFieldInfos

Methods

demoteFieldInfos :: proxy fs -> NP FieldInfo xs Source #

Given a proxy of some type-level field information, return the corresponding term-level information as a product.

Since: 0.3.0.0

Instances

DemoteFieldInfos ([] :: [FieldInfo]) ([] :: [*]) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteFieldInfos :: proxy [] -> NP FieldInfo0 [] Source #
(DemoteFieldInfo f x, DemoteFieldInfos fs xs) => DemoteFieldInfos (f ': fs) (x ': xs) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteFieldInfos :: proxy (f ': fs) -> NP FieldInfo (x ': xs) Source #

class DemoteConstructorInfo (x :: ConstructorInfo) (xs :: [*]) where Source #

Class for computing term-level constructor information from type-level constructor information.

Since: 0.3.0.0

Minimal complete definition

demoteConstructorInfo

Methods

demoteConstructorInfo :: proxy x -> ConstructorInfo xs Source #

Given a proxy of some type-level constructor information, return the corresponding term-level information.

Since: 0.3.0.0

Instances

(KnownSymbol s, SListI xs) => DemoteConstructorInfo (Constructor s) xs Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfo :: proxy (Constructor s) -> ConstructorInfo xs Source #
(KnownSymbol s, DemoteFieldInfos fs xs) => DemoteConstructorInfo (Record s fs) xs Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfo :: proxy (Record s fs) -> ConstructorInfo xs Source #
(KnownSymbol s, DemoteAssociativity a, KnownNat f) => DemoteConstructorInfo (Infix s a f) (y ': (z ': ([] :: [*]))) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfo :: proxy (Infix s a f) -> ConstructorInfo (y ': (z ': [])) Source #

class DemoteConstructorInfos (cs :: [ConstructorInfo]) (xss :: [[*]]) where Source #

Class for computing term-level constructor information from type-level constructor information.

Since: 0.3.0.0

Minimal complete definition

demoteConstructorInfos

Methods

demoteConstructorInfos :: proxy cs -> NP ConstructorInfo xss Source #

Given a proxy of some type-level constructor information, return the corresponding term-level information as a product.

Since: 0.3.0.0

Instances

DemoteConstructorInfos ([] :: [ConstructorInfo]) ([] :: [[*]]) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfos :: proxy [] -> NP ConstructorInfo0 [] Source #
(DemoteConstructorInfo c xs, DemoteConstructorInfos cs xss) => DemoteConstructorInfos (c ': cs) (xs ': xss) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfos :: proxy (c ': cs) -> NP ConstructorInfo (xs ': xss) Source #

class DemoteDatatypeInfo (x :: DatatypeInfo) (xss :: [[*]]) where Source #

Class for computing term-level datatype information from type-level datatype information.

Since: 0.3.0.0

Minimal complete definition

demoteDatatypeInfo

Methods

demoteDatatypeInfo :: proxy x -> DatatypeInfo xss Source #

Given a proxy of some type-level datatype information, return the corresponding term-level information.

Since: 0.3.0.0

Instances

(KnownSymbol m, KnownSymbol d, DemoteConstructorInfos cs xss) => DemoteDatatypeInfo (ADT m d cs) xss Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteDatatypeInfo :: proxy (ADT m d cs) -> DatatypeInfo xss Source #
(KnownSymbol m, KnownSymbol d, DemoteConstructorInfo c (x ': ([] :: []))) => DemoteDatatypeInfo (Newtype m d c) ((x ': ([] :: [])) ': ([] :: [[*]])) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteDatatypeInfo :: proxy (Newtype m d c) -> DatatypeInfo ((x ': []) ': []) Source #

type Fixity = Nat Source #

The fixity of an infix constructor.

type FieldName = Symbol Source #

The name of a field / record selector.

type ConstructorName = Symbol Source #

The name of a data constructor.

type ModuleName = Symbol Source #

The name of a module.

type DatatypeName = Symbol Source #

The name of a datatype.

data FieldInfo Source #

Metadata for a single record field (to be used promoted).

Since: 0.3.0.0

Constructors

FieldInfo FieldName

Instances

DemoteFieldInfos ([] :: [FieldInfo]) ([] :: [*]) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteFieldInfos :: proxy [] -> NP FieldInfo0 [] Source #
(DemoteFieldInfo f x, DemoteFieldInfos fs xs) => DemoteFieldInfos (f ': fs) (x ': xs) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteFieldInfos :: proxy (f ': fs) -> NP FieldInfo (x ': xs) Source #

data ConstructorInfo Source #

Metadata for a single constructors (to be used promoted).

Since: 0.3.0.0

Constructors

Constructor ConstructorName	Normal constructor
Infix ConstructorName Associativity Fixity	Infix constructor
Record ConstructorName [FieldInfo]	Record constructor

Instances

DemoteConstructorInfos ([] :: [ConstructorInfo]) ([] :: [[*]]) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfos :: proxy [] -> NP ConstructorInfo0 [] Source #
(DemoteConstructorInfo c xs, DemoteConstructorInfos cs xss) => DemoteConstructorInfos (c ': cs) (xs ': xss) Source #
Instance details Defined in Generics.SOP.Type.Metadata Methods demoteConstructorInfos :: proxy (c ': cs) -> NP ConstructorInfo (xs ': xss) Source #

data DatatypeInfo Source #

Metadata for a datatype (to be used promoted).

A type of kind DatatypeInfo contains meta-information about a datatype that is not contained in its code. This information consists primarily of the names of the datatype, its constructors, and possibly its record selectors.

The constructor indicates whether the datatype has been declared using newtype or not.

Since: 0.3.0.0

Constructors

ADT ModuleName DatatypeName [ConstructorInfo]	Standard algebraic datatype
Newtype ModuleName DatatypeName ConstructorInfo	Newtype

re-exports

data Associativity #

Datatype to represent the associativity of a constructor

Constructors

LeftAssociative
RightAssociative
NotAssociative

Instances

Bounded Associativity
Instance details Defined in GHC.Generics Methods minBound :: Associativity # maxBound :: Associativity #
Enum Associativity
Instance details Defined in GHC.Generics Methods succ :: Associativity -> Associativity # pred :: Associativity -> Associativity # toEnum :: Int -> Associativity # fromEnum :: Associativity -> Int # enumFrom :: Associativity -> [Associativity] # enumFromThen :: Associativity -> Associativity -> [Associativity] # enumFromTo :: Associativity -> Associativity -> [Associativity] # enumFromThenTo :: Associativity -> Associativity -> Associativity -> [Associativity] #
Eq Associativity
Instance details Defined in GHC.Generics Methods (==) :: Associativity -> Associativity -> Bool # (/=) :: Associativity -> Associativity -> Bool #
Data Associativity	Since: base-4.9.0.0
Instance details Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Associativity -> c Associativity # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Associativity # toConstr :: Associativity -> Constr # dataTypeOf :: Associativity -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Associativity) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Associativity) # gmapT :: (forall b. Data b => b -> b) -> Associativity -> Associativity # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Associativity -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Associativity -> r # gmapQ :: (forall d. Data d => d -> u) -> Associativity -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Associativity -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Associativity -> m Associativity #
Ord Associativity
Instance details Defined in GHC.Generics Methods compare :: Associativity -> Associativity -> Ordering # (<) :: Associativity -> Associativity -> Bool # (<=) :: Associativity -> Associativity -> Bool # (>) :: Associativity -> Associativity -> Bool # (>=) :: Associativity -> Associativity -> Bool # max :: Associativity -> Associativity -> Associativity # min :: Associativity -> Associativity -> Associativity #
Read Associativity
Instance details Defined in GHC.Generics Methods readsPrec :: Int -> ReadS Associativity # readList :: ReadS [Associativity] # readPrec :: ReadPrec Associativity # readListPrec :: ReadPrec [Associativity] #
Show Associativity
Instance details Defined in GHC.Generics Methods showsPrec :: Int -> Associativity -> ShowS # show :: Associativity -> String # showList :: [Associativity] -> ShowS #
Ix Associativity
Instance details Defined in GHC.Generics Methods range :: (Associativity, Associativity) -> [Associativity] # index :: (Associativity, Associativity) -> Associativity -> Int # unsafeIndex :: (Associativity, Associativity) -> Associativity -> Int inRange :: (Associativity, Associativity) -> Associativity -> Bool # rangeSize :: (Associativity, Associativity) -> Int # unsafeRangeSize :: (Associativity, Associativity) -> Int
Generic Associativity
Instance details Defined in GHC.Generics Associated Types type Rep Associativity :: * -> * # Methods from :: Associativity -> Rep Associativity x # to :: Rep Associativity x -> Associativity #
SingKind Associativity	Since: base-4.0.0.0
Instance details Defined in GHC.Generics Associated Types type DemoteRep Associativity :: * Methods fromSing :: Sing a -> DemoteRep Associativity
SingI LeftAssociative	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing LeftAssociative
SingI RightAssociative	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing RightAssociative
SingI NotAssociative	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing NotAssociative
type Rep Associativity
Instance details Defined in GHC.Generics type Rep Associativity = D1 (MetaData "Associativity" "GHC.Generics" "base" False) (C1 (MetaCons "LeftAssociative" PrefixI False) (U1 :: * -> ) :+: (C1 (MetaCons "RightAssociative" PrefixI False) (U1 :: -> ) :+: C1 (MetaCons "NotAssociative" PrefixI False) (U1 :: -> *)))
data Sing (a :: Associativity)
Instance details Defined in GHC.Generics data Sing (a :: Associativity) where SLeftAssociative :: Sing LeftAssociative SRightAssociative :: Sing RightAssociative SNotAssociative :: Sing NotAssociative
type DemoteRep Associativity
Instance details Defined in GHC.Generics type DemoteRep Associativity = Associativity