ghc-8.0.2: The GHC API

Safe Haskell | None
Language | Haskell2010

TyCon

Contents

- Main TyCon data types
  - Field labels
  - Constructing TyCons
  - Predicates on TyCons
  - Extracting information out of TyCons
  - Manipulating TyCons
- Runtime type representation
- Primitive representations of Types
- Recursion breaking

Synopsis

- data TyCon
- data AlgTyConRhs
  - = AbstractTyCon Bool
  - | DataTyCon {
    - data_cons :: [DataCon]
    - is_enum :: Bool
    }
  - | TupleTyCon {
    - data_con :: DataCon
    - tup_sort :: TupleSort
    }
  - | NewTyCon {
    - data_con :: DataCon
    - nt_rhs :: Type
    - nt_etad_rhs :: ([TyVar], Type)
    - nt_co :: CoAxiom Unbranched
    }
- visibleDataCons :: AlgTyConRhs -> [DataCon]
- data AlgTyConFlav
  - = VanillaAlgTyCon TyConRepName
  - | UnboxedAlgTyCon
  - | ClassTyCon Class TyConRepName
  - | DataFamInstTyCon (CoAxiom Unbranched) TyCon [Type]
- isNoParent :: AlgTyConFlav -> Bool
- data FamTyConFlav
  - = DataFamilyTyCon TyConRepName
  - | OpenSynFamilyTyCon
  - | ClosedSynFamilyTyCon (Maybe (CoAxiom Branched))
  - | AbstractClosedSynFamilyTyCon
  - | BuiltInSynFamTyCon BuiltInSynFamily
- data Role
  - = Nominal
  - | Representational
  - | Phantom
- data Injectivity
  - = NotInjective
  - | Injective [Bool]
- data RuntimeRepInfo
  - = NoRRI
  - | RuntimeRep ([Type] -> PrimRep)
  - | VecCount Int
  - | VecElem PrimElemRep
- tyConFieldLabels :: TyCon -> [FieldLabel]
- tyConFieldLabelEnv :: TyCon -> FieldLabelEnv
- mkAlgTyCon :: Name -> [TyBinder] -> Kind -> [TyVar] -> [Role] -> Maybe CType -> [PredType] -> AlgTyConRhs -> AlgTyConFlav -> RecFlag -> Bool -> TyCon
- mkClassTyCon :: Name -> [TyBinder] -> [TyVar] -> [Role] -> AlgTyConRhs -> Class -> RecFlag -> Name -> TyCon
- mkFunTyCon :: Name -> [TyBinder] -> Name -> TyCon
- mkPrimTyCon :: Name -> [TyBinder] -> Kind -> [Role] -> TyCon
- mkKindTyCon :: Name -> [TyBinder] -> Kind -> [Role] -> Name -> TyCon
- mkLiftedPrimTyCon :: Name -> [TyBinder] -> Kind -> [Role] -> TyCon
- mkTupleTyCon :: Name -> [TyBinder] -> Kind -> Arity -> [TyVar] -> DataCon -> TupleSort -> AlgTyConFlav -> TyCon
- mkSynonymTyCon :: Name -> [TyBinder] -> Kind -> [TyVar] -> [Role] -> Type -> TyCon
- mkFamilyTyCon :: Name -> [TyBinder] -> Kind -> [TyVar] -> Maybe Name -> FamTyConFlav -> Maybe Class -> Injectivity -> TyCon
- mkPromotedDataCon :: DataCon -> Name -> TyConRepName -> [TyBinder] -> Kind -> [Role] -> RuntimeRepInfo -> TyCon
- mkTcTyCon :: Name -> [TyVar] -> [TyBinder] -> Kind -> Bool -> [TyVar] -> TyCon
- isAlgTyCon :: TyCon -> Bool
- isVanillaAlgTyCon :: TyCon -> Bool
- isClassTyCon :: TyCon -> Bool
- isFamInstTyCon :: TyCon -> Bool
- isFunTyCon :: TyCon -> Bool
- isPrimTyCon :: TyCon -> Bool
- isTupleTyCon :: TyCon -> Bool
- isUnboxedTupleTyCon :: TyCon -> Bool
- isBoxedTupleTyCon :: TyCon -> Bool
- isTypeSynonymTyCon :: TyCon -> Bool
- mightBeUnsaturatedTyCon :: TyCon -> Bool
- isPromotedDataCon :: TyCon -> Bool
- isPromotedDataCon_maybe :: TyCon -> Maybe DataCon
- isKindTyCon :: TyCon -> Bool
- isLiftedTypeKindTyConName :: Name -> Bool
- isDataTyCon :: TyCon -> Bool
- isProductTyCon :: TyCon -> Bool
- isDataProductTyCon_maybe :: TyCon -> Maybe DataCon
- isEnumerationTyCon :: TyCon -> Bool
- isNewTyCon :: TyCon -> Bool
- isAbstractTyCon :: TyCon -> Bool
- isFamilyTyCon :: TyCon -> Bool
- isOpenFamilyTyCon :: TyCon -> Bool
- isTypeFamilyTyCon :: TyCon -> Bool
- isDataFamilyTyCon :: TyCon -> Bool
- isOpenTypeFamilyTyCon :: TyCon -> Bool
- isClosedSynFamilyTyConWithAxiom_maybe :: TyCon -> Maybe (CoAxiom Branched)
- familyTyConInjectivityInfo :: TyCon -> Injectivity
- isBuiltInSynFamTyCon_maybe :: TyCon -> Maybe BuiltInSynFamily
- isUnliftedTyCon :: TyCon -> Bool
- isGadtSyntaxTyCon :: TyCon -> Bool
- isInjectiveTyCon :: TyCon -> Role -> Bool
- isGenerativeTyCon :: TyCon -> Role -> Bool
- isGenInjAlgRhs :: AlgTyConRhs -> Bool
- isTyConAssoc :: TyCon -> Bool
- tyConAssoc_maybe :: TyCon -> Maybe Class
- isRecursiveTyCon :: TyCon -> Bool
- isImplicitTyCon :: TyCon -> Bool
- isTyConWithSrcDataCons :: TyCon -> Bool
- isTcTyCon :: TyCon -> Bool
- tyConName :: TyCon -> Name
- tyConKind :: TyCon -> Kind
- tyConUnique :: TyCon -> Unique
- tyConTyVars :: TyCon -> [TyVar]
- tyConCType :: TyCon -> Maybe CType
- tyConCType_maybe :: TyCon -> Maybe CType
- tyConDataCons :: TyCon -> [DataCon]
- tyConDataCons_maybe :: TyCon -> Maybe [DataCon]
- tyConSingleDataCon_maybe :: TyCon -> Maybe DataCon
- tyConSingleDataCon :: TyCon -> DataCon
- tyConSingleAlgDataCon_maybe :: TyCon -> Maybe DataCon
- tyConFamilySize :: TyCon -> Int
- tyConStupidTheta :: TyCon -> [PredType]
- tyConArity :: TyCon -> Arity
- tyConRoles :: TyCon -> [Role]
- tyConFlavour :: TyCon -> String
- tyConTuple_maybe :: TyCon -> Maybe TupleSort
- tyConClass_maybe :: TyCon -> Maybe Class
- tyConATs :: TyCon -> [TyCon]
- tyConFamInst_maybe :: TyCon -> Maybe (TyCon, [Type])
- tyConFamInstSig_maybe :: TyCon -> Maybe (TyCon, [Type], CoAxiom Unbranched)
- tyConFamilyCoercion_maybe :: TyCon -> Maybe (CoAxiom Unbranched)
- tyConFamilyResVar_maybe :: TyCon -> Maybe Name
- synTyConDefn_maybe :: TyCon -> Maybe ([TyVar], Type)
- synTyConRhs_maybe :: TyCon -> Maybe Type
- famTyConFlav_maybe :: TyCon -> Maybe FamTyConFlav
- famTcResVar :: TyCon -> Maybe Name
- algTyConRhs :: TyCon -> AlgTyConRhs
- newTyConRhs :: TyCon -> ([TyVar], Type)
- newTyConEtadArity :: TyCon -> Int
- newTyConEtadRhs :: TyCon -> ([TyVar], Type)
- unwrapNewTyCon_maybe :: TyCon -> Maybe ([TyVar], Type, CoAxiom Unbranched)
- unwrapNewTyConEtad_maybe :: TyCon -> Maybe ([TyVar], Type, CoAxiom Unbranched)
- newTyConDataCon_maybe :: TyCon -> Maybe DataCon
- algTcFields :: TyCon -> FieldLabelEnv
- tyConRuntimeRepInfo :: TyCon -> RuntimeRepInfo
- tyConBinders :: TyCon -> [TyBinder]
- tyConResKind :: TyCon -> Kind
- tcTyConScopedTyVars :: TyCon -> [TyVar]
- expandSynTyCon_maybe :: TyCon -> [tyco] -> Maybe ([(TyVar, tyco)], Type, [tyco])
- makeTyConAbstract :: TyCon -> TyCon
- newTyConCo :: TyCon -> CoAxiom Unbranched
- newTyConCo_maybe :: TyCon -> Maybe (CoAxiom Unbranched)
- pprPromotionQuote :: TyCon -> SDoc
- type TyConRepName = Name
- tyConRepName_maybe :: TyCon -> Maybe TyConRepName
- mkPrelTyConRepName :: Name -> TyConRepName
- tyConRepModOcc :: Module -> OccName -> (Module, OccName)
- data PrimRep
  - = VoidRep
  - | PtrRep
  - | IntRep
  - | WordRep
  - | Int64Rep
  - | Word64Rep
  - | AddrRep
  - | FloatRep
  - | DoubleRep
  - | VecRep Int PrimElemRep
- data PrimElemRep
  - = Int8ElemRep
  - | Int16ElemRep
  - | Int32ElemRep
  - | Int64ElemRep
  - | Word8ElemRep
  - | Word16ElemRep
  - | Word32ElemRep
  - | Word64ElemRep
  - | FloatElemRep
  - | DoubleElemRep
- isVoidRep :: PrimRep -> Bool
- isGcPtrRep :: PrimRep -> Bool
- primRepSizeW :: DynFlags -> PrimRep -> Int
- primElemRepSizeB :: PrimElemRep -> Int
- primRepIsFloat :: PrimRep -> Maybe Bool
- data RecTcChecker
- initRecTc :: RecTcChecker
- checkRecTc :: RecTcChecker -> TyCon -> Maybe RecTcChecker

# Main TyCon data types

data TyCon Source #

TyCons represent type constructors. Type constructors are introduced by things such as:

1) Data declarations: `data Foo = ...` creates the `Foo` type constructor of kind `*`

2) Type synonyms: `type Foo = ...` creates the `Foo` type constructor

3) Newtypes: `newtype Foo a = MkFoo ...` creates the `Foo` type constructor of kind `* -> *`

4) Class declarations: `class Foo where` creates the `Foo` type constructor of kind `*`

This data type also encodes a number of primitive, built in type constructors such as those for function and tuple types.

Instances

Eq TyCon # |
Methods (==) :: TyCon -> TyCon -> Bool # (/=) :: TyCon -> TyCon -> Bool #
Data TyCon # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> TyCon -> c TyCon Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c TyCon Source # toConstr :: TyCon -> Constr Source # dataTypeOf :: TyCon -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c TyCon) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c TyCon) Source # gmapT :: (forall b. Data b => b -> b) -> TyCon -> TyCon Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> TyCon -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> TyCon -> r Source # gmapQ :: (forall d. Data d => d -> u) -> TyCon -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> TyCon -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> TyCon -> m TyCon Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> TyCon -> m TyCon Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> TyCon -> m TyCon Source #
Ord TyCon # |
Methods compare :: TyCon -> TyCon -> Ordering # (<) :: TyCon -> TyCon -> Bool # (<=) :: TyCon -> TyCon -> Bool # (>) :: TyCon -> TyCon -> Bool # (>=) :: TyCon -> TyCon -> Bool # max :: TyCon -> TyCon -> TyCon # min :: TyCon -> TyCon -> TyCon #
Outputable TyCon # |
Methods ppr :: TyCon -> SDoc Source # pprPrec :: Rational -> TyCon -> SDoc Source #
Uniquable TyCon # |
Methods getUnique :: TyCon -> Unique Source #
NamedThing TyCon # |
Methods getOccName :: TyCon -> OccName Source # getName :: TyCon -> Name Source #

data AlgTyConRhs Source #

Represents right-hand-sides of `TyCon`s for algebraic types

Constructors

AbstractTyCon Bool | Says that we know nothing about this data type, except that it's represented by a pointer. Used when we export a data type abstractly into an .hi file.
DataTyCon | Information about those `TyCon`s derived from a `data` declaration. This includes data types with no constructors at all.
Fields data_cons :: [DataCon] The data type constructors; can be empty if the user declares the type to have no constructors INVARIANT: Kept in order of increasing `DataCon` tag (see the tag assignment in DataCon.mkDataCon) is_enum :: Bool Cached value: is this an enumeration type? See Note [Enumeration types]
TupleTyCon |
Fields data_con :: DataCon The unique constructor for the `newtype`. It has no existentials tup_sort :: TupleSort Is this a boxed, unboxed or constraint tuple?
NewTyCon | Information about those `TyCon`s derived from a `newtype` declaration
Fields data_con :: DataCon The unique constructor for the `newtype`. It has no existentials nt_rhs :: Type Cached value: the argument type of the constructor, which is just the representation type of the `TyCon` (remember that `newtype`s do not exist at runtime so need a different representation type). The free `TyVar`s of this type are the `tyConTyVars` from the corresponding `TyCon` nt_etad_rhs :: ([TyVar], Type) Same as the `nt_rhs`, but this time eta-reduced. Hence the list of `TyVar`s in this field may be shorter than the declared arity of the `TyCon`. nt_co :: CoAxiom Unbranched

visibleDataCons :: AlgTyConRhs -> [DataCon] Source #

Both type classes as well as family instances imply implicit type constructors. These implicit type constructors refer to their parent structure (ie, the class or family from which they derive) using a type of the following form.

Extract those `DataCon`s that we are able to learn about. Note that visibility in this sense does not correspond to visibility in the context of any particular user program!

data AlgTyConFlav Source #

Constructors

VanillaAlgTyCon TyConRepName | An ordinary type constructor has no parent.
UnboxedAlgTyCon | An unboxed type constructor. Note that this carries no TyConRepName as it is not representable.
ClassTyCon Class TyConRepName | Type constructors representing a class dictionary. See Note [ATyCon for classes] in TyCoRep
DataFamInstTyCon (CoAxiom Unbranched) TyCon [Type] | Type constructors representing an *instance* of a *data* family. Parameters: 1) The type family in question 2) Instance types; free variables are the `tyConTyVars` of the current `TyCon` (not the family one). INVARIANT: the number of types matches the arity of the family `TyCon` 3) A `CoTyCon` identifying the representation type with the type instance family

Instances

Outputable AlgTyConFlav # |
Methods ppr :: AlgTyConFlav -> SDoc Source # pprPrec :: Rational -> AlgTyConFlav -> SDoc Source #

isNoParent :: AlgTyConFlav -> Bool Source #

data FamTyConFlav Source #

Information pertaining to the expansion of a type synonym (`type`)

Constructors

DataFamilyTyCon TyConRepName | Represents an open type family without a fixed right hand side. Additional instances can appear at any time. These are introduced by either a top level declaration:
    data family T a :: *
Or an associated data type declaration, within a class declaration:
    class C a b where
      data T b :: *
OpenSynFamilyTyCon | An open type synonym family e.g. `type family F x y :: * -> *`
ClosedSynFamilyTyCon (Maybe (CoAxiom Branched)) | A closed type synonym family e.g. `type family F x where { F Int = Bool }`
AbstractClosedSynFamilyTyCon | A closed type synonym family declared in an hs-boot file with type family F a where ..
BuiltInSynFamTyCon BuiltInSynFamily | Built-in type family used by the TypeNats solver

data Role Source #

Constructors

Nominal |
Representational |
Phantom |

Instances

Eq Role # |
Methods (==) :: Role -> Role -> Bool # (/=) :: Role -> Role -> Bool #
Data Role # |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Role -> c Role Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Role Source # toConstr :: Role -> Constr Source # dataTypeOf :: Role -> DataType Source # dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c Role) Source # dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Role) Source # gmapT :: (forall b. Data b => b -> b) -> Role -> Role Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Role -> r Source # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Role -> r Source # gmapQ :: (forall d. Data d => d -> u) -> Role -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> Role -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Role -> m Role Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Role -> m Role Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Role -> m Role Source #
Ord Role # |
Methods compare :: Role -> Role -> Ordering # (<) :: Role -> Role -> Bool # (<=) :: Role -> Role -> Bool # (>) :: Role -> Role -> Bool # (>=) :: Role -> Role -> Bool # max :: Role -> Role -> Role # min :: Role -> Role -> Role #
Outputable Role # |
Methods ppr :: Role -> SDoc Source # pprPrec :: Rational -> Role -> SDoc Source #
Binary Role # |
Methods put_ :: BinHandle -> Role -> IO () Source # put :: BinHandle -> Role -> IO (Bin Role) Source # get :: BinHandle -> IO Role Source #

data Injectivity Source #

Constructors

NotInjective |
Injective [Bool] |

Instances

Eq Injectivity # |
Methods (==) :: Injectivity -> Injectivity -> Bool # (/=) :: Injectivity -> Injectivity -> Bool #
Binary Injectivity # |
Methods put_ :: BinHandle -> Injectivity -> IO () Source # put :: BinHandle -> Injectivity -> IO (Bin Injectivity) Source # get :: BinHandle -> IO Injectivity Source #

data RuntimeRepInfo Source #

Some promoted datacons signify extra info relevant to GHC. For example, the `IntRep` constructor of `RuntimeRep` corresponds to the `IntRep` constructor of `PrimRep`. This data structure allows us to store this information right in the `TyCon`. The other approach would be to look up things like `RuntimeRep`'s `PrimRep` by known-key every time.

Constructors

NoRRI | an ordinary promoted data con
RuntimeRep ([Type] -> PrimRep) | A constructor of `RuntimeRep`. The argument to the function should be the list of arguments to the promoted datacon.
VecCount Int | A constructor of `VecCount`
VecElem PrimElemRep | A constructor of `VecElem`

## Field labels

tyConFieldLabels :: TyCon -> [FieldLabel] Source #

The labels for the fields of this particular `TyCon`

tyConFieldLabelEnv :: TyCon -> FieldLabelEnv Source #

The labels for the fields of this particular `TyCon`

## Constructing TyCons

mkAlgTyCon Source #

Arguments

:: Name |
-> [TyBinder] | Binders of the resulting `TyCon`
-> Kind | Result kind
-> [TyVar] | `TyVar`s scoped over: see `tyConTyVars`. Arity is inferred from the length of this list
-> [Role] | The roles for each TyVar
-> Maybe CType | The C type this type corresponds to when using the CAPI FFI
-> [PredType] | Stupid theta: see `algTcStupidTheta`
-> AlgTyConRhs | Information about data constructors
-> AlgTyConFlav | What flavour is it? (e.g. vanilla, type family)
-> RecFlag | Is the `TyCon` recursive?
-> Bool | Was the `TyCon` declared with GADT syntax?
-> TyCon |

This is the making of an algebraic `TyCon`. Notably, you have to pass in the generic (in the -XGenerics sense) information about the type constructor - you can get hold of it easily (see Generics module)

mkClassTyCon :: Name -> [TyBinder] -> [TyVar] -> [Role] -> AlgTyConRhs -> Class -> RecFlag -> Name -> TyCon Source #

Simpler specialization of `mkAlgTyCon` for classes

mkFunTyCon :: Name -> [TyBinder] -> Name -> TyCon Source #

Given the name of the function type constructor and it's kind, create the corresponding `TyCon`. It is reccomended to use `funTyCon` if you want this functionality

mkPrimTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | result kind
-> [Role] |
-> TyCon |

Create an unlifted primitive `TyCon`, such as `Int#`

mkKindTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | result kind
-> [Role] |
-> Name |
-> TyCon |

Kind constructors

mkLiftedPrimTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | result kind
-> [Role] |
-> TyCon |

Create a lifted primitive `TyCon` such as `RealWorld`

mkTupleTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | Result kind of the `TyCon`
-> Arity | Arity of the tuple
-> [TyVar] | `TyVar`s scoped over: see `tyConTyVars`
-> DataCon |
-> TupleSort | Whether the tuple is boxed or unboxed
-> AlgTyConFlav |
-> TyCon |

mkSynonymTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | result kind
-> [TyVar] |
-> [Role] |
-> Type |
-> TyCon |

Create a type synonym `TyCon`

mkFamilyTyCon Source #

Arguments

:: Name |
-> [TyBinder] |
-> Kind | result kind
-> [TyVar] |
-> Maybe Name |
-> FamTyConFlav |
-> Maybe Class |
-> Injectivity |
-> TyCon |

Create a type family `TyCon`

mkPromotedDataCon :: DataCon -> Name -> TyConRepName -> [TyBinder] -> Kind -> [Role] -> RuntimeRepInfo -> TyCon Source #

Create a promoted data constructor `TyCon` Somewhat dodgily, we give it the same Name as the data constructor itself; when we pretty-print the TyCon we add a quote; see the Outputable TyCon instance

mkTcTyCon Source #

Arguments

:: Name |
-> [TyVar] |
-> [TyBinder] |
-> Kind | result kind only
-> Bool | Can this be unsaturated?
-> [TyVar] | Scoped type variables, see Note [TcTyCon]
-> TyCon |

Makes a tycon suitable for use during type-checking. The only real need for this is for printing error messages during a recursive type/class type-checking knot. It has a kind because TcErrors sometimes calls typeKind. See also Note [Kind checking recursive type and class declarations] in TcTyClsDecls.

## Predicates on TyCons

isAlgTyCon :: TyCon -> Bool Source #

Returns `True` if the supplied `TyCon` resulted from either a `data` or `newtype` declaration

isVanillaAlgTyCon :: TyCon -> Bool Source #

Returns `True` for vanilla AlgTyCons -- that is, those created with a `data` or `newtype` declaration.

isClassTyCon :: TyCon -> Bool Source #

Is this `TyCon` that for a class instance?

isFamInstTyCon :: TyCon -> Bool Source #

Is this `TyCon` that for a data family instance?

isFunTyCon :: TyCon -> Bool Source #

isPrimTyCon :: TyCon -> Bool Source #

Does this `TyCon` represent something that cannot be defined in Haskell?

isTupleTyCon :: TyCon -> Bool Source #

Does this `TyCon` represent a tuple?

NB: when compiling `Data.Tuple`, the tycons won't reply `True` to `isTupleTyCon`, because they are built as `AlgTyCons`. However they get spat into the interface file as tuple tycons, so I don't think it matters.

isUnboxedTupleTyCon :: TyCon -> Bool Source #

Is this the `TyCon` for an unboxed tuple?

isBoxedTupleTyCon :: TyCon -> Bool Source #

Is this the `TyCon` for a boxed tuple?

isTypeSynonymTyCon :: TyCon -> Bool Source #

Is this a `TyCon` representing a regular H98 type synonym (`type`)?

mightBeUnsaturatedTyCon :: TyCon -> Bool Source #

True iff we can decompose (T a b c) into ((T a b) c) I.e. is it injective and generative w.r.t nominal equality? That is, if (T a b) ~N d e f, is it always the case that (T ~N d), (a ~N e) and (b ~N f)? Specifically NOT true of synonyms (open and otherwise)

It'd be unusual to call mightBeUnsaturatedTyCon on a regular H98 type synonym, because you should probably have expanded it first But regardless, it's not decomposable

isPromotedDataCon :: TyCon -> Bool Source #

Is this a PromotedDataCon?

isPromotedDataCon_maybe :: TyCon -> Maybe DataCon Source #

Retrieves the promoted DataCon if this is a PromotedDataCon;

isKindTyCon :: TyCon -> Bool Source #

Is this tycon really meant for use at the kind level? That is, should it be permitted without -XDataKinds?

isLiftedTypeKindTyConName :: Name -> Bool Source #

isDataTyCon :: TyCon -> Bool Source #

Returns `True` for data types that are definitely represented by heap-allocated constructors. These are scrutinised by Core-level `case` expressions, and they get info tables allocated for them.

Generally, the function will be true for all `data` types and false for `newtype`s, unboxed tuples and type family `TyCon`s. But it is not guaranteed to return `True` in all cases that it could.

NB: for a data type family, only the instance `TyCon`s get an info table. The family declaration `TyCon` does not

isProductTyCon :: TyCon -> Bool Source #

isDataProductTyCon_maybe :: TyCon -> Maybe DataCon Source #

isEnumerationTyCon :: TyCon -> Bool Source #

Is this an algebraic `TyCon` which is just an enumeration of values?

isNewTyCon :: TyCon -> Bool Source #

Is this `TyCon` that for a `newtype`

isAbstractTyCon :: TyCon -> Bool Source #

Test if the `TyCon` is algebraic but abstract (invisible data constructors)

isFamilyTyCon :: TyCon -> Bool Source #

Is this a `TyCon`, synonym or otherwise, that defines a family?

isOpenFamilyTyCon :: TyCon -> Bool Source #

Is this a `TyCon`, synonym or otherwise, that defines a family with instances?

isTypeFamilyTyCon :: TyCon -> Bool Source #

Is this a synonym `TyCon` that can have may have further instances appear?

isDataFamilyTyCon :: TyCon -> Bool Source #

Is this a synonym `TyCon` that can have may have further instances appear?

isOpenTypeFamilyTyCon :: TyCon -> Bool Source #

Is this an open type family TyCon?

isClosedSynFamilyTyConWithAxiom_maybe :: TyCon -> Maybe (CoAxiom Branched) Source #

Is this a non-empty closed type family? Returns `Nothing` for abstract or empty closed families.

familyTyConInjectivityInfo :: TyCon -> Injectivity Source #

Try to read the injectivity information from a FamilyTyCon. For every other TyCon this function panics.

isBuiltInSynFamTyCon_maybe :: TyCon -> Maybe BuiltInSynFamily Source #

isUnliftedTyCon :: TyCon -> Bool Source #

Is this `TyCon` unlifted (i.e. cannot contain bottom)? Note that this can only be true for primitive and unboxed-tuple `TyCon`s

isGadtSyntaxTyCon :: TyCon -> Bool Source #

Is this an algebraic `TyCon` declared with the GADT syntax?

isInjectiveTyCon :: TyCon -> Role -> Bool Source #

`isInjectiveTyCon` is true of `TyCon`s for which this property holds (where X is the role passed in): If (T a1 b1 c1) ~X (T a2 b2 c2), then (a1 ~X1 a2), (b1 ~X2 b2), and (c1 ~X3 c2) (where X1, X2, and X3, are the roles given by tyConRolesX tc X) See also Note [Decomposing equalities] in TcCanonical

isGenerativeTyCon :: TyCon -> Role -> Bool Source #

`isGenerativeTyCon` is true of `TyCon`s for which this property holds (where X is the role passed in): If (T tys ~X t), then (t's head ~X T). See also Note [Decomposing equalities] in TcCanonical

isGenInjAlgRhs :: AlgTyConRhs -> Bool Source #

Is this an `AlgTyConRhs` of a `TyCon` that is generative and injective with respect to representational equality?

isTyConAssoc :: TyCon -> Bool Source #

Are we able to extract information `TyVar` to class argument list mapping from a given `TyCon`?

tyConAssoc_maybe :: TyCon -> Maybe Class Source #

isRecursiveTyCon :: TyCon -> Bool Source #

Is this a recursive `TyCon`?

isImplicitTyCon :: TyCon -> Bool Source #

Identifies implicit tycons that, in particular, do not go into interface files (because they are implicitly reconstructed when the interface is read).

Note that:

- Associated families are implicit, as they are re-constructed from the class declaration in which they reside, and
- Family instances are not implicit as they represent the instance body (similar to a `dfun` does that for a class instance).
- Tuples are implicit iff they have a wired-in name (namely: boxed and unboxed tupeles are wired-in and implicit, but constraint tuples are not)

isTyConWithSrcDataCons :: TyCon -> Bool Source #

Check if the tycon actually refers to a proper `data` or `newtype` with user defined constructors rather than one from a class or other construction.

isTcTyCon :: TyCon -> Bool Source #

Is this a TcTyCon? (That is, one only used during type-checking?)

## Extracting information out of TyCons

tyConName :: TyCon -> Name Source #

Name of the constructor

tyConKind :: TyCon -> Kind Source #

Kind of this TyCon (full kind, not just the return kind)

tyConUnique :: TyCon -> Unique Source #

A Unique of this TyCon. Invariant: identical to Unique of Name stored in tyConName field.

tyConTyVars :: TyCon -> [TyVar] Source #

The kind and type variables used in the type constructor. Invariant: length tyvars = arity Precisely, this list scopes over:

1. The `algTcStupidTheta`
2. The cached types in algTyConRhs.NewTyCon
3. The family instance types if present

Note that it does not scope over the data constructors.

tyConCType :: TyCon -> Maybe CType Source #

The C type that should be used for this type when using the FFI and CAPI

tyConCType_maybe :: TyCon -> Maybe CType Source #

tyConDataCons :: TyCon -> [DataCon] Source #

As `tyConDataCons_maybe`, but returns the empty list of constructors if no constructors could be found

tyConDataCons_maybe :: TyCon -> Maybe [DataCon] Source #

Determine the `DataCon`s originating from the given `TyCon`, if the `TyCon` is the sort that can have any constructors (note: this does not include abstract algebraic types)

tyConSingleDataCon_maybe :: TyCon -> Maybe DataCon Source #

If the given `TyCon` has a single data constructor, i.e. it is a `data` type with one alternative, a tuple type or a `newtype` then that constructor is returned. If the `TyCon` has more than one constructor, or represents a primitive or function type constructor then `Nothing` is returned. In any other case, the function panics

tyConSingleDataCon :: TyCon -> DataCon Source #

tyConSingleAlgDataCon_maybe :: TyCon -> Maybe DataCon Source #

tyConFamilySize :: TyCon -> Int Source #

Determine the number of value constructors a `TyCon` has. Panics if the `TyCon` is not algebraic or a tuple

tyConStupidTheta :: TyCon -> [PredType] Source #

Find the "stupid theta" of the `TyCon`. A "stupid theta" is the context to the left of an algebraic type declaration, e.g. `Eq a` in the declaration `data Eq a => T a ...`

tyConArity :: TyCon -> Arity Source #

Number of arguments this TyCon must receive to be considered saturated (including implicit kind variables)

tyConRoles :: TyCon -> [Role] Source #

Get the list of roles for the type parameters of a TyCon

tyConFlavour :: TyCon -> String Source #

tyConTuple_maybe :: TyCon -> Maybe TupleSort Source #

tyConClass_maybe :: TyCon -> Maybe Class Source #

If this `TyCon` is that for a class instance, return the class it is for. Otherwise returns `Nothing`

tyConATs :: TyCon -> [TyCon] Source #

Return the associated types of the `TyCon`, if any

tyConFamInst_maybe :: TyCon -> Maybe (TyCon, [Type]) Source #

If this `TyCon` is that of a data family instance, return the family in question and the instance types. Otherwise, return `Nothing`

tyConFamInstSig_maybe :: TyCon -> Maybe (TyCon, [Type], CoAxiom Unbranched) Source #

tyConFamilyCoercion_maybe :: TyCon -> Maybe (CoAxiom Unbranched) Source #

If this `TyCon` is that of a data family instance, return a `TyCon` which represents a coercion identifying the representation type with the type instance family. Otherwise, return `Nothing`

tyConFamilyResVar_maybe :: TyCon -> Maybe Name Source #

Extract type variable naming the result of injective type family

synTyConDefn_maybe :: TyCon -> Maybe ([TyVar], Type) Source #

Extract the `TyVar`s bound by a vanilla type synonym and the corresponding (unsubstituted) right hand side.

synTyConRhs_maybe :: TyCon -> Maybe Type Source #

Extract the information pertaining to the right hand side of a type synonym (`type`) declaration.

famTyConFlav_maybe :: TyCon -> Maybe FamTyConFlav Source #

Extract the flavour of a type family (with all the extra information that it carries)

famTcResVar :: TyCon -> Maybe Name Source #

Name of result type variable, used for pretty-printing with --show-iface and for reifying TyCon in Template Haskell

algTyConRhs :: TyCon -> AlgTyConRhs Source #

Extract an `AlgTyConRhs` with information about data constructors from an algebraic or tuple `TyCon`. Panics for any other sort of `TyCon`

newTyConRhs :: TyCon -> ([TyVar], Type) Source #

Extract the bound type variables and type expansion of a type synonym `TyCon`. Panics if the `TyCon` is not a synonym

newTyConEtadArity :: TyCon -> Int Source #

The number of type parameters that need to be passed to a newtype to resolve it. May be less than in the definition if it can be eta-contracted.

newTyConEtadRhs :: TyCon -> ([TyVar], Type) Source #

Extract the bound type variables and type expansion of an eta-contracted type synonym `TyCon`. Panics if the `TyCon` is not a synonym

unwrapNewTyCon_maybe :: TyCon -> Maybe ([TyVar], Type, CoAxiom Unbranched) Source #

Take a `TyCon` apart into the `TyVar`s it scopes over, the `Type` it expands into, and (possibly) a coercion from the representation type to the `newtype`. Returns `Nothing` if this is not possible.

unwrapNewTyConEtad_maybe :: TyCon -> Maybe ([TyVar], Type, CoAxiom Unbranched) Source #

newTyConDataCon_maybe :: TyCon -> Maybe DataCon Source #

algTcFields :: TyCon -> FieldLabelEnv Source #

Maps a label to information about the field

tyConRuntimeRepInfo :: TyCon -> RuntimeRepInfo Source #

Extract any `RuntimeRepInfo` from this TyCon

tyConBinders :: TyCon -> [TyBinder] Source #

The TyBinders for this TyCon's kind. length tyConBinders == tyConArity. This is a cached value and is redundant with the tyConKind.

tyConResKind :: TyCon -> Kind Source #

Cached result kind

tcTyConScopedTyVars :: TyCon -> [TyVar] Source #

Scoped tyvars over the tycon's body. See Note [TcTyCon]

## Manipulating TyCons

expandSynTyCon_maybe Source #

Arguments

:: TyCon |
-> [tyco] | Arguments to `TyCon`
-> Maybe ([(TyVar, tyco)], Type, [tyco]) | Returns a `TyVar` substitution, the body type of the synonym (not yet substituted) and any arguments remaining from the application

Expand a type synonym application, if any

makeTyConAbstract :: TyCon -> TyCon Source #

Make an fake, abstract `TyCon` from an existing one. Used when recovering from errors

newTyConCo :: TyCon -> CoAxiom Unbranched Source #

newTyConCo_maybe :: TyCon -> Maybe (CoAxiom Unbranched) Source #

Extracts the `newtype` coercion from such a `TyCon`, which can be used to construct something with the `newtype`s type from its representation type (right hand side). If the supplied `TyCon` is not a `newtype`, returns `Nothing`

pprPromotionQuote :: TyCon -> SDoc Source #

# Runtime type representation

type TyConRepName = Name Source #

tyConRepName_maybe :: TyCon -> Maybe TyConRepName Source #

mkPrelTyConRepName :: Name -> TyConRepName Source #

Make a `Name` for the `Typeable` representation of the given wired-in type

tyConRepModOcc :: Module -> OccName -> (Module, OccName) Source #

The name (and defining module) for the Typeable representation (TyCon) of a type constructor.

See Note [Grand plan for Typeable] in `TcTypeable` in TcTypeable.

# Primitive representations of Types

data PrimRep Source #

A `PrimRep` is an abstraction of a type. It contains information that the code generator needs in order to pass arguments, return results, and store values of this type.

Constructors

VoidRep |
PtrRep |
IntRep | Signed, word-sized value
WordRep | Unsigned, word-sized value
Int64Rep | Signed, 64 bit value (with 32-bit words only)
Word64Rep | Unsigned, 64 bit value (with 32-bit words only)
AddrRep | A pointer, but not to a Haskell value (use `PtrRep`)
FloatRep |
DoubleRep |
VecRep Int PrimElemRep | A vector

Instances

Eq PrimRep # |
Methods (==) :: PrimRep -> PrimRep -> Bool # (/=) :: PrimRep -> PrimRep -> Bool #
Show PrimRep # |
Methods showsPrec :: Int -> PrimRep -> ShowS Source # show :: PrimRep -> String Source # showList :: [PrimRep] -> ShowS Source #
Outputable PrimRep # |
Methods ppr :: PrimRep -> SDoc Source # pprPrec :: Rational -> PrimRep -> SDoc Source #

data PrimElemRep Source #

Constructors

Int8ElemRep |
Int16ElemRep |
Int32ElemRep |
Int64ElemRep |
Word8ElemRep |
Word16ElemRep |
Word32ElemRep |
Word64ElemRep |
FloatElemRep |
DoubleElemRep |

Instances

Eq PrimElemRep # |
Methods (==) :: PrimElemRep -> PrimElemRep -> Bool # (/=) :: PrimElemRep -> PrimElemRep -> Bool #
Show PrimElemRep # |
Methods showsPrec :: Int -> PrimElemRep -> ShowS Source # show :: PrimElemRep -> String Source # showList :: [PrimElemRep] -> ShowS Source #
Outputable PrimElemRep # |
Methods ppr :: PrimElemRep -> SDoc Source # pprPrec :: Rational -> PrimElemRep -> SDoc Source #

isVoidRep :: PrimRep -> Bool Source #

isGcPtrRep :: PrimRep -> Bool Source #

primRepSizeW :: DynFlags -> PrimRep -> Int Source #

Find the size of a `PrimRep`, in words

primElemRepSizeB :: PrimElemRep -> Int Source #

primRepIsFloat :: PrimRep -> Maybe Bool Source #

Return if Rep stands for floating type, returns Nothing for vector types.

# Recursion breaking

data RecTcChecker Source #

initRecTc :: RecTcChecker Source #

checkRecTc :: RecTcChecker -> TyCon -> Maybe RecTcChecker Source #