ghc-9.6.0.20230210: The GHC API
Safe HaskellSafe-Inferred
LanguageHaskell2010

GHC.Core.DataCon

Synopsis

Main data types

data DataCon Source #

A data constructor

Instances

Instances details
Data DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> DataCon -> c DataCon Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c DataCon Source #

toConstr :: DataCon -> Constr Source #

dataTypeOf :: DataCon -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c DataCon) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c DataCon) Source #

gmapT :: (forall b. Data b => b -> b) -> DataCon -> DataCon Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> DataCon -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> DataCon -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> DataCon -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> DataCon -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> DataCon -> m DataCon Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> DataCon -> m DataCon Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> DataCon -> m DataCon Source #

NamedThing DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Uniquable DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Outputable DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

ppr :: DataCon -> SDoc Source #

OutputableBndr DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Eq DataCon Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

(==) :: DataCon -> DataCon -> Bool #

(/=) :: DataCon -> DataCon -> Bool #

data DataConRep Source #

Data Constructor Representation See Note [Data constructor workers and wrappers]

data SrcStrictness Source #

Source Strictness

What strictness annotation the user wrote

Constructors

SrcLazy

Lazy, ie ~

SrcStrict

Strict, ie !

NoSrcStrict

no strictness annotation

Instances

Instances details
Data SrcStrictness Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SrcStrictness -> c SrcStrictness Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SrcStrictness Source #

toConstr :: SrcStrictness -> Constr Source #

dataTypeOf :: SrcStrictness -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c SrcStrictness) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SrcStrictness) Source #

gmapT :: (forall b. Data b => b -> b) -> SrcStrictness -> SrcStrictness Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SrcStrictness -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SrcStrictness -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> SrcStrictness -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> SrcStrictness -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> SrcStrictness -> m SrcStrictness Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SrcStrictness -> m SrcStrictness Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SrcStrictness -> m SrcStrictness Source #

Binary SrcStrictness Source # 
Instance details

Defined in GHC.Core.DataCon

Outputable SrcStrictness Source # 
Instance details

Defined in GHC.Core.DataCon

Eq SrcStrictness Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

data SrcUnpackedness Source #

Source Unpackedness

What unpackedness the user requested

Constructors

SrcUnpack

{-# UNPACK #-} specified

SrcNoUnpack

{-# NOUNPACK #-} specified

NoSrcUnpack

no unpack pragma

Instances

Instances details
Data SrcUnpackedness Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SrcUnpackedness -> c SrcUnpackedness Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SrcUnpackedness Source #

toConstr :: SrcUnpackedness -> Constr Source #

dataTypeOf :: SrcUnpackedness -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c SrcUnpackedness) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SrcUnpackedness) Source #

gmapT :: (forall b. Data b => b -> b) -> SrcUnpackedness -> SrcUnpackedness Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SrcUnpackedness -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SrcUnpackedness -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> SrcUnpackedness -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> SrcUnpackedness -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> SrcUnpackedness -> m SrcUnpackedness Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SrcUnpackedness -> m SrcUnpackedness Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SrcUnpackedness -> m SrcUnpackedness Source #

Binary SrcUnpackedness Source # 
Instance details

Defined in GHC.Core.DataCon

Outputable SrcUnpackedness Source # 
Instance details

Defined in GHC.Core.DataCon

Eq SrcUnpackedness Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

data HsSrcBang Source #

Haskell Source Bang

Bangs on data constructor arguments as the user wrote them in the source code.

(HsSrcBang _ SrcUnpack SrcLazy) and (HsSrcBang _ SrcUnpack NoSrcStrict) (without StrictData) makes no sense, we emit a warning (in checkValidDataCon) and treat it like (HsSrcBang _ NoSrcUnpack SrcLazy)

Instances

Instances details
Data HsSrcBang Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> HsSrcBang -> c HsSrcBang Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c HsSrcBang Source #

toConstr :: HsSrcBang -> Constr Source #

dataTypeOf :: HsSrcBang -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c HsSrcBang) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c HsSrcBang) Source #

gmapT :: (forall b. Data b => b -> b) -> HsSrcBang -> HsSrcBang Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> HsSrcBang -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> HsSrcBang -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> HsSrcBang -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> HsSrcBang -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> HsSrcBang -> m HsSrcBang Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> HsSrcBang -> m HsSrcBang Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> HsSrcBang -> m HsSrcBang Source #

Outputable HsSrcBang Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

ppr :: HsSrcBang -> SDoc Source #

data HsImplBang Source #

Haskell Implementation Bang

Bangs of data constructor arguments as generated by the compiler after consulting HsSrcBang, flags, etc.

Constructors

HsLazy

Lazy field, or one with an unlifted type

HsStrict Bool

Strict but not unpacked field True = we could have unpacked, but opted not to because of -O0. See Note [Detecting useless UNPACK pragmas]

HsUnpack (Maybe Coercion)

Strict and unpacked field co :: arg-ty ~ product-ty HsBang

Instances

Instances details
Data HsImplBang Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> HsImplBang -> c HsImplBang Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c HsImplBang Source #

toConstr :: HsImplBang -> Constr Source #

dataTypeOf :: HsImplBang -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c HsImplBang) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c HsImplBang) Source #

gmapT :: (forall b. Data b => b -> b) -> HsImplBang -> HsImplBang Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> HsImplBang -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> HsImplBang -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> HsImplBang -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> HsImplBang -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> HsImplBang -> m HsImplBang Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> HsImplBang -> m HsImplBang Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> HsImplBang -> m HsImplBang Source #

Outputable HsImplBang Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

ppr :: HsImplBang -> SDoc Source #

type ConTag = Int Source #

A *one-index* constructor tag

Type of the tags associated with each constructor possibility or superclass selector

Equality specs

data EqSpec Source #

An EqSpec is a tyvar/type pair representing an equality made in rejigging a GADT constructor

Instances

Instances details
Outputable EqSpec Source # 
Instance details

Defined in GHC.Core.DataCon

Methods

ppr :: EqSpec -> SDoc Source #

mkEqSpec :: TyVar -> Type -> EqSpec Source #

Make a non-dependent EqSpec

Field labels

data FieldLabel Source #

Fields in an algebraic record type; see Note [FieldLabel].

Constructors

FieldLabel 

Fields

Instances

Instances details
Data FieldLabel Source # 
Instance details

Defined in GHC.Types.FieldLabel

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> FieldLabel -> c FieldLabel Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c FieldLabel Source #

toConstr :: FieldLabel -> Constr Source #

dataTypeOf :: FieldLabel -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c FieldLabel) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c FieldLabel) Source #

gmapT :: (forall b. Data b => b -> b) -> FieldLabel -> FieldLabel Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> FieldLabel -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> FieldLabel -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> FieldLabel -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> FieldLabel -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> FieldLabel -> m FieldLabel Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> FieldLabel -> m FieldLabel Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> FieldLabel -> m FieldLabel Source #

NFData FieldLabel Source # 
Instance details

Defined in GHC.Types.FieldLabel

Methods

rnf :: FieldLabel -> () Source #

HasOccName FieldLabel Source # 
Instance details

Defined in GHC.Types.FieldLabel

Binary Name => Binary FieldLabel Source #

We need the Binary Name constraint here even though there is an instance defined in GHC.Types.Name, because the we have a SOURCE import, so the instance is not in scope. And the instance cannot be added to Name.hs-boot because GHC.Utils.Binary itself depends on GHC.Types.Name.

Instance details

Defined in GHC.Types.FieldLabel

Outputable FieldLabel Source # 
Instance details

Defined in GHC.Types.FieldLabel

Methods

ppr :: FieldLabel -> SDoc Source #

Eq FieldLabel Source # 
Instance details

Defined in GHC.Types.FieldLabel

data FieldLabelString Source #

Field labels are just represented as strings; they are not necessarily unique (even within a module)

Instances

Instances details
Data FieldLabelString Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> FieldLabelString -> c FieldLabelString Source #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c FieldLabelString Source #

toConstr :: FieldLabelString -> Constr Source #

dataTypeOf :: FieldLabelString -> DataType Source #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c FieldLabelString) Source #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c FieldLabelString) Source #

gmapT :: (forall b. Data b => b -> b) -> FieldLabelString -> FieldLabelString Source #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> FieldLabelString -> r Source #

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> FieldLabelString -> r Source #

gmapQ :: (forall d. Data d => d -> u) -> FieldLabelString -> [u] Source #

gmapQi :: Int -> (forall d. Data d => d -> u) -> FieldLabelString -> u Source #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> FieldLabelString -> m FieldLabelString Source #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> FieldLabelString -> m FieldLabelString Source #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> FieldLabelString -> m FieldLabelString Source #

NFData FieldLabelString Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

Methods

rnf :: FieldLabelString -> () Source #

Uniquable FieldLabelString Source # 
Instance details

Defined in GHC.Types.FieldLabel

Outputable FieldLabelString Source # 
Instance details

Defined in GHC.Types.FieldLabel

Eq FieldLabelString Source # 
Instance details

Defined in Language.Haskell.Syntax.Basic

type Anno FieldLabelString Source # 
Instance details

Defined in GHC.Hs.Expr

Type construction

mkDataCon Source #

Arguments

:: Name 
-> Bool

Is the constructor declared infix?

-> TyConRepName

TyConRepName for the promoted TyCon

-> [HsSrcBang]

Strictness/unpack annotations, from user

-> [FieldLabel]

Field labels for the constructor, if it is a record, otherwise empty

-> [TyVar]

Universals.

-> [TyCoVar]

Existentials.

-> [InvisTVBinder]

User-written TyVarBinders. These must be Inferred/Specified. See Note [TyVarBinders in DataCons]

-> [EqSpec]

GADT equalities

-> KnotTied ThetaType

Theta-type occurring before the arguments proper

-> [KnotTied (Scaled Type)]

Original argument types

-> KnotTied Type

Original result type

-> PromDataConInfo

See comments on PromDataConInfo

-> KnotTied TyCon

Representation type constructor

-> ConTag

Constructor tag

-> ThetaType

The "stupid theta", context of the data declaration e.g. data Eq a => T a ...

-> Id

Worker Id

-> DataConRep

Representation

-> DataCon 

Build a new data constructor

fIRST_TAG :: ConTag Source #

Tags are allocated from here for real constructors or for superclass selectors

Type deconstruction

dataConRepType :: DataCon -> Type Source #

The representation type of the data constructor, i.e. the sort type that will represent values of this type at runtime

dataConInstSig :: DataCon -> [Type] -> ([TyCoVar], ThetaType, [Type]) Source #

Instantiate the universal tyvars of a data con, returning ( instantiated existentials , instantiated constraints including dependent GADT equalities which are *also* listed in the instantiated existentials , instantiated args)

dataConFullSig :: DataCon -> ([TyVar], [TyCoVar], [EqSpec], ThetaType, [Scaled Type], Type) Source #

The "full signature" of the DataCon returns, in order:

1) The result of dataConUnivTyVars

2) The result of dataConExTyCoVars

3) The non-dependent GADT equalities. Dependent GADT equalities are implied by coercion variables in return value (2).

4) The other constraints of the data constructor type, excluding GADT equalities

5) The original argument types to the DataCon (i.e. before any change of the representation of the type) with linearity annotations

6) The original result type of the DataCon

dataConName :: DataCon -> Name Source #

The Name of the DataCon, giving it a unique, rooted identification

dataConIdentity :: DataCon -> ByteString Source #

The string package:module.name identifying a constructor, which is attached to its info table and used by the GHCi debugger and the heap profiler

dataConTag :: DataCon -> ConTag Source #

The tag used for ordering DataCons

dataConTyCon :: DataCon -> TyCon Source #

The type constructor that we are building via this data constructor

dataConOrigTyCon :: DataCon -> TyCon Source #

The original type constructor used in the definition of this data constructor. In case of a data family instance, that will be the family type constructor.

dataConWrapperType :: DataCon -> Type Source #

The user-declared type of the data constructor in the nice-to-read form:

T :: forall a b. a -> b -> T [a]

rather than:

T :: forall a c. forall b. (c~[a]) => a -> b -> T c

The type variables are quantified in the order that the user wrote them. See Note [DataCon user type variable binders].

NB: If the constructor is part of a data instance, the result type mentions the family tycon, not the internal one.

dataConUnivTyVars :: DataCon -> [TyVar] Source #

The universally-quantified type variables of the constructor

dataConExTyCoVars :: DataCon -> [TyCoVar] Source #

The existentially-quantified type/coercion variables of the constructor including dependent (kind-) GADT equalities

dataConUnivAndExTyCoVars :: DataCon -> [TyCoVar] Source #

Both the universal and existential type/coercion variables of the constructor

dataConUserTyVars :: DataCon -> [TyVar] Source #

The type variables of the constructor, in the order the user wrote them

dataConUserTyVarBinders :: DataCon -> [InvisTVBinder] Source #

InvisTVBinders for the type variables of the constructor, in the order the user wrote them

dataConTheta :: DataCon -> ThetaType Source #

The *full* constraints on the constructor type, including dependent GADT equalities.

dataConStupidTheta :: DataCon -> ThetaType Source #

The "stupid theta" of the DataCon, such as data Eq a in:

data Eq a => T a = ...

See Note [The stupid context].

dataConOtherTheta :: DataCon -> ThetaType Source #

Returns constraints in the wrapper type, other than those in the dataConEqSpec

dataConInstArgTys Source #

Arguments

:: DataCon

A datacon with no existentials or equality constraints However, it can have a dcTheta (notably it can be a class dictionary, with superclasses)

-> [Type]

Instantiated at these types

-> [Scaled Type] 

Finds the instantiated types of the arguments required to construct a DataCon representation NB: these INCLUDE any dictionary args but EXCLUDE the data-declaration context, which is discarded It's all post-flattening etc; this is a representation type

dataConOrigArgTys :: DataCon -> [Scaled Type] Source #

Returns the argument types of the wrapper, excluding all dictionary arguments and without substituting for any type variables

dataConInstOrigArgTys :: DataCon -> [Type] -> [Scaled Type] Source #

Returns just the instantiated value argument types of a DataCon, (excluding dictionary args)

dataConRepArgTys :: DataCon -> [Scaled Type] Source #

Returns the arg types of the worker, including *all* non-dependent evidence, after any flattening has been done and without substituting for any type variables

dataConResRepTyArgs :: DataCon -> [Type] Source #

Were the type variables of the data con written in a different order than the regular order (universal tyvars followed by existential tyvars)?

This is not a cheap test, so we minimize its use in GHC as much as possible. Currently, its only call site in the GHC codebase is in mkDataConRep in MkId, and so dataConUserTyVarsNeedWrapper is only called at most once during a data constructor's lifetime.

dataConInstUnivs :: DataCon -> [Type] -> [Type] Source #

Given a data constructor dc with n universally quantified type variables a_{1}, a_{2}, ..., a_{n}, and given a list of argument types dc_args of length m where m <= n, then:

dataConInstUnivs dc dc_args

Will return:

[dc_arg_{1}, dc_arg_{2}, ..., dc_arg_{m}, a_{m+1}, ..., a_{n}]

That is, return the list of universal type variables with a_{1}, a_{2}, ..., a_{m} instantiated with dc_arg_{1}, dc_arg_{2}, ..., dc_arg_{m}. It is possible for m to be less than n, in which case the remaining n - m elements will simply be universal type variables (with their kinds possibly instantiated).

Examples:

  • Given the data constructor D :: forall a b. Foo a b and dc_args [Int, Bool], then dataConInstUnivs D dc_args will return [Int, Bool].
  • Given the data constructor D :: forall a b. Foo a b and dc_args [Int], then @dataConInstUnivs D dc_args will return [Int, b].
  • Given the data constructor E :: forall k (a :: k). Bar k a and dc_args [Type], then @dataConInstUnivs D dc_args will return [Type, (a :: Type)].

This is primarily used in GHC.Tc.Deriv.* in service of instantiating data constructors' field types. See Note [Instantiating field types in stock deriving] for a notable example of this.

dataConFieldLabels :: DataCon -> [FieldLabel] Source #

The labels for the fields of this particular DataCon

dataConFieldType :: DataCon -> FieldLabelString -> Type Source #

Extract the type for any given labelled field of the DataCon

dataConFieldType_maybe :: DataCon -> FieldLabelString -> Maybe (FieldLabel, Type) Source #

Extract the label and type for any given labelled field of the DataCon, or return Nothing if the field does not belong to it

dataConSrcBangs :: DataCon -> [HsSrcBang] Source #

Strictness/unpack annotations, from user; or, for imported DataCons, from the interface file The list is in one-to-one correspondence with the arity of the DataCon

dataConSourceArity :: DataCon -> Arity Source #

Source-level arity of the data constructor

dataConRepArity :: DataCon -> Arity Source #

Gives the number of actual fields in the representation of the data constructor. This may be more than appear in the source code; the extra ones are the existentially quantified dictionaries

dataConIsInfix :: DataCon -> Bool Source #

Should the DataCon be presented infix?

dataConWorkId :: DataCon -> Id Source #

Get the Id of the DataCon worker: a function that is the "actual" constructor and has no top level binding in the program. The type may be different from the obvious one written in the source program. Panics if there is no such Id for this DataCon

dataConWrapId :: DataCon -> Id Source #

Returns an Id which looks like the Haskell-source constructor by using the wrapper if it exists (see dataConWrapId_maybe) and failing over to the worker (see dataConWorkId)

dataConWrapId_maybe :: DataCon -> Maybe Id Source #

Get the Id of the DataCon wrapper: a function that wraps the "actual" constructor so it has the type visible in the source program: c.f. dataConWorkId. Returns Nothing if there is no wrapper, which occurs for an algebraic data constructor and also for a newtype (whose constructor is inlined compulsorily)

dataConImplicitTyThings :: DataCon -> [TyThing] Source #

Find all the Ids implicitly brought into scope by the data constructor. Currently, the union of the dataConWorkId and the dataConWrapId

dataConRepStrictness :: DataCon -> [StrictnessMark] Source #

Give the demands on the arguments of a Core constructor application (Con dc args)

splitDataProductType_maybe Source #

Arguments

:: Type

A product type, perhaps

-> Maybe (TyCon, [Type], DataCon, [Scaled Type]) 

Extract the type constructor, type argument, data constructor and it's representation argument types from a type if it is a product type.

Precisely, we return Just for any data type that is all of:

  • Concrete (i.e. constructors visible)
  • Single-constructor
  • ... which has no existentials

Whether the type is a data type or a newtype.

Predicates on DataCons

isNullarySrcDataCon :: DataCon -> Bool Source #

Return whether there are any argument types for this DataCons original source type See Note [DataCon arities]

isNullaryRepDataCon :: DataCon -> Bool Source #

Return whether there are any argument types for this DataCons runtime representation type See Note [DataCon arities]

isVanillaDataCon :: DataCon -> Bool Source #

Vanilla DataCons are those that are nice boring Haskell 98 constructors

isNewDataCon :: DataCon -> Bool Source #

Is this the DataCon of a newtype?

isTypeDataCon :: DataCon -> Bool Source #

Is this data constructor in a "type data" declaration? See Note [Type data declarations] in GHC.Rename.Module.

eqHsBang :: HsImplBang -> HsImplBang -> Bool Source #

Compare strictness annotations

specialPromotedDc :: DataCon -> Bool Source #

Should this DataCon be allowed in a type even without -XDataKinds? Currently, only Lifted & Unlifted

Promotion related functions

Orphan instances