TcType

Documentation

type TcType = Type

type TcSigmaType = TcType

type TcRhoType = TcType

type TcTauType = TcType

type TcPredType = PredType

type TcThetaType = ThetaType

type TcTyVar = TyVar

type TcTyVarSet = TyVarSet

type TcDTyVarSet = DTyVarSet

type TcTyCoVarSet = TyCoVarSet

type TcDTyCoVarSet = DTyCoVarSet

type TcKind = Kind

type TcCoVar = CoVar

type TcTyCoVar = Var

type TcTyVarBinder = TyVarBinder

type TcTyCon = TyCon

data ExpType

An expected type to check against during type-checking. See Note [ExpType] in TcMType, where you'll also find manipulators.

Constructors

Check TcType

Infer !InferResult

Instances

Outputable ExpType

Defined in TcType

Methods

ppr :: ExpType -> SDoc

pprPrec :: Rational -> ExpType -> SDoc

data InferResult

Constructors

IR

Fields

• ir_uniq :: Unique
• ir_lvl :: TcLevel
• ir_inst :: Bool
• ir_ref :: IORef (Maybe TcType)

Instances

Outputable InferResult

Defined in TcType

Methods

ppr :: InferResult -> SDoc

pprPrec :: Rational -> InferResult -> SDoc

type ExpSigmaType = ExpType

type ExpRhoType = ExpType

mkCheckExpType :: TcType -> ExpType

Make an ExpType suitable for checking.

data SyntaxOpType

What to expect for an argument to a rebindable-syntax operator. Quite like Type, but allows for holes to be filled in by tcSyntaxOp. The callback called from tcSyntaxOp gets a list of types; the meaning of these types is determined by a left-to-right depth-first traversal of the SyntaxOpType tree. So if you pass in

SynAny `SynFun` (SynList `SynFun` SynType Int) `SynFun` SynAny

you'll get three types back: one for the first SynAny, the element type of the list, and one for the last SynAny. You don't get anything for the SynType, because you've said positively that it should be an Int, and so it shall be.

This is defined here to avoid defining it in TcExpr.hs-boot.

Constructors

SynAny

Any type

SynRho

A rho type, deeply skolemised or instantiated as appropriate

SynList

A list type. You get back the element type of the list

SynFun SyntaxOpType SyntaxOpType infixr 0

A function.

SynType ExpType

A known type.

synKnownType :: TcType -> SyntaxOpType

Like SynType but accepts a regular TcType

mkSynFunTys :: [SyntaxOpType] -> ExpType -> SyntaxOpType

Like mkFunTys but for SyntaxOpType

newtype TcLevel

Constructors

TcLevel Int

Instances

Eq TcLevel

Defined in TcType

Methods

(==) :: TcLevel -> TcLevel -> Bool

(/=) :: TcLevel -> TcLevel -> Bool

Ord TcLevel

Defined in TcType

Methods

compare :: TcLevel -> TcLevel -> Ordering

(<) :: TcLevel -> TcLevel -> Bool

(<=) :: TcLevel -> TcLevel -> Bool

(>) :: TcLevel -> TcLevel -> Bool

(>=) :: TcLevel -> TcLevel -> Bool

max :: TcLevel -> TcLevel -> TcLevel

min :: TcLevel -> TcLevel -> TcLevel

Outputable TcLevel

Defined in TcType

Methods

ppr :: TcLevel -> SDoc

pprPrec :: Rational -> TcLevel -> SDoc

topTcLevel :: TcLevel

pushTcLevel :: TcLevel -> TcLevel

isTopTcLevel :: TcLevel -> Bool

strictlyDeeperThan :: TcLevel -> TcLevel -> Bool

sameDepthAs :: TcLevel -> TcLevel -> Bool

fmvTcLevel :: TcLevel

tcTypeLevel :: TcType -> TcLevel

tcTyVarLevel :: TcTyVar -> TcLevel

maxTcLevel :: TcLevel -> TcLevel -> TcLevel

data UserTypeCtxt

Constructors

FunSigCtxt Name Bool

InfSigCtxt Name

ExprSigCtxt

TypeAppCtxt

ConArgCtxt Name

TySynCtxt Name

PatSynCtxt Name

PatSigCtxt

RuleSigCtxt Name

ResSigCtxt

ForSigCtxt Name

DefaultDeclCtxt

InstDeclCtxt

SpecInstCtxt

ThBrackCtxt

GenSigCtxt

GhciCtxt

ClassSCCtxt Name

SigmaCtxt

DataTyCtxt Name

DerivClauseCtxt

pprUserTypeCtxt :: UserTypeCtxt -> SDoc

isSigMaybe :: UserTypeCtxt -> Maybe Name

data TcTyVarDetails

Constructors

SkolemTv TcLevel Bool

RuntimeUnk

MetaTv

Fields

• mtv_info :: MetaInfo
• mtv_ref :: IORef MetaDetails
• mtv_tclvl :: TcLevel

pprTcTyVarDetails :: TcTyVarDetails -> SDoc

vanillaSkolemTv :: TcTyVarDetails

superSkolemTv :: TcTyVarDetails

data MetaDetails

Constructors

Flexi

Indirect TcType

Instances

Outputable MetaDetails

Defined in TcType

Methods

ppr :: MetaDetails -> SDoc

pprPrec :: Rational -> MetaDetails -> SDoc

data MetaInfo

Constructors

TauTv

SigTv

FlatMetaTv

FlatSkolTv

isImmutableTyVar :: TyVar -> Bool

isSkolemTyVar :: TcTyVar -> Bool

isMetaTyVar :: TcTyVar -> Bool

isMetaTyVarTy :: TcType -> Bool

isTyVarTy :: Type -> Bool

isSigTyVar :: Var -> Bool

isOverlappableTyVar :: TcTyVar -> Bool

isTyConableTyVar :: TcTyVar -> Bool

isFskTyVar :: TcTyVar -> Bool

isFmvTyVar :: TcTyVar -> Bool

isFlattenTyVar :: TcTyVar -> Bool

True of both given and wanted flatten-skolems (fak and usk)

isAmbiguousTyVar :: TcTyVar -> Bool

metaTyVarRef :: TyVar -> IORef MetaDetails

metaTyVarInfo :: TcTyVar -> MetaInfo

isFlexi :: MetaDetails -> Bool

isIndirect :: MetaDetails -> Bool

isRuntimeUnkSkol :: TyVar -> Bool

metaTyVarTcLevel :: TcTyVar -> TcLevel

setMetaTyVarTcLevel :: TcTyVar -> TcLevel -> TcTyVar

metaTyVarTcLevel_maybe :: TcTyVar -> Maybe TcLevel

isTouchableMetaTyVar :: TcLevel -> TcTyVar -> Bool

isTouchableOrFmv :: TcLevel -> TcTyVar -> Bool

isFloatedTouchableMetaTyVar :: TcLevel -> TcTyVar -> Bool

findDupSigTvs :: [(Name, TcTyVar)] -> [(Name, Name)]

mkTyVarNamePairs :: [TyVar] -> [(Name, TyVar)]

mkPhiTy :: [PredType] -> Type -> Type

mkInfSigmaTy :: [TyVar] -> [PredType] -> Type -> Type

Make a sigma ty where all type variables are Inferred. That is, they cannot be used with visible type application.

mkSpecSigmaTy :: [TyVar] -> [PredType] -> Type -> Type

Make a sigma ty where all type variables are "specified". That is, they can be used with visible type application

mkSigmaTy :: [TyVarBinder] -> [PredType] -> Type -> Type

mkNakedTyConApp :: TyCon -> [Type] -> Type

mkNakedAppTys :: Type -> [Type] -> Type

mkNakedAppTy :: Type -> Type -> Type

mkNakedCastTy :: Type -> Coercion -> Type

getTyVar :: String -> Type -> TyVar

Attempts to obtain the type variable underlying a Type, and panics with the given message if this is not a type variable type. See also getTyVar_maybe

tcSplitForAllTy_maybe :: Type -> Maybe (TyVarBinder, Type)

tcSplitForAllTys :: Type -> ([TyVar], Type)

Like tcSplitPiTys, but splits off only named binders, returning just the tycovars.

tcSplitPiTys :: Type -> ([TyBinder], Type)

Splits a forall type into a list of TyBinders and the inner type. Always succeeds, even if it returns an empty list.

tcSplitPiTy_maybe :: Type -> Maybe (TyBinder, Type)

Splits a type into a TyBinder and a body, if possible. Panics otherwise

tcSplitForAllTyVarBndrs :: Type -> ([TyVarBinder], Type)

Like tcSplitForAllTys, but splits off only named binders.

tcSplitPhiTy :: Type -> (ThetaType, Type)

tcSplitPredFunTy_maybe :: Type -> Maybe (PredType, Type)

tcSplitFunTy_maybe :: Type -> Maybe (Type, Type)

tcSplitFunTys :: Type -> ([Type], Type)

tcFunArgTy :: Type -> Type

tcFunResultTy :: Type -> Type

tcFunResultTyN :: HasDebugCallStack => Arity -> Type -> Type

Strips off n *visible* arguments and returns the resulting type

tcSplitFunTysN :: Arity -> TcRhoType -> Either Arity ([TcSigmaType], TcSigmaType)

Split off exactly the specified number argument types Returns (Left m) if there are m missing arrows in the type (Right (tys,res)) if the type looks like t1 -> ... -> tn -> res

tcSplitTyConApp :: Type -> (TyCon, [Type])

tcSplitTyConApp_maybe :: HasCallStack => Type -> Maybe (TyCon, [Type])

Split a type constructor application into its type constructor and applied types. Note that this may fail in the case of a FunTy with an argument of unknown kind FunTy (e.g. FunTy (a :: k) Int. since the kind of a isn't of the form TYPE rep). Consequently, you may need to zonk your type before using this function.

If you only need the TyCon, consider using tcTyConAppTyCon_maybe.

tcRepSplitTyConApp_maybe :: HasCallStack => Type -> Maybe (TyCon, [Type])

Like tcSplitTyConApp_maybe but doesn't look through type synonyms.

tcRepSplitTyConApp_maybe' :: HasCallStack => Type -> Maybe (TyCon, [Type])

Like tcRepSplitTyConApp_maybe, but returns Nothing if,

1. the type is structurally not a type constructor application, or
2. the type is a function type (e.g. application of funTyCon), but we currently don't even enough information to fully determine its RuntimeRep variables. For instance, FunTy (a :: k) Int.

By contrast tcRepSplitTyConApp_maybe panics in the second case.

The behavior here is needed during canonicalization; see Note [FunTy and decomposing tycon applications] in TcCanonical for details.

tcTyConAppTyCon :: Type -> TyCon

tcTyConAppTyCon_maybe :: Type -> Maybe TyCon

Like tcRepSplitTyConApp_maybe, but only returns the TyCon.

tcTyConAppArgs :: Type -> [Type]

tcSplitAppTy_maybe :: Type -> Maybe (Type, Type)

tcSplitAppTy :: Type -> (Type, Type)

tcSplitAppTys :: Type -> (Type, [Type])

tcRepSplitAppTy_maybe :: Type -> Maybe (Type, Type)

Does the AppTy split as in tcSplitAppTy_maybe, but assumes that any coreView stuff is already done. Refuses to look through (c => t)

tcRepGetNumAppTys :: Type -> Arity

Returns the number of arguments in the given type, without looking through synonyms. This is used only for error reporting. We don't look through synonyms because of #11313.

tcGetCastedTyVar_maybe :: Type -> Maybe (TyVar, CoercionN)

If the type is a tyvar, possibly under a cast, returns it, along with the coercion. Thus, the co is :: kind tv ~N kind type

tcGetTyVar_maybe :: Type -> Maybe TyVar

tcGetTyVar :: String -> Type -> TyVar

nextRole :: Type -> Role

What is the role assigned to the next parameter of this type? Usually, this will be Nominal, but if the type is a TyConApp, we may be able to do better. The type does *not* have to be well-kinded when applied for this to work!

tcSplitSigmaTy :: Type -> ([TyVar], ThetaType, Type)

Split a sigma type into its parts.

tcSplitNestedSigmaTys :: Type -> ([TyVar], ThetaType, Type)

Split a sigma type into its parts, going underneath as many ForAllTys as possible. For example, given this type synonym:

type Traversal s t a b = forall f. Applicative f => (a -> f b) -> s -> f t

if you called tcSplitSigmaTy on this type:

forall s t a b. Each s t a b => Traversal s t a b

then it would return ([s,t,a,b], [Each s t a b], Traversal s t a b). But if you instead called tcSplitNestedSigmaTys on the type, it would return ([s,t,a,b,f], [Each s t a b, Applicative f], (a -> f b) -> s -> f t).

tcDeepSplitSigmaTy_maybe :: TcSigmaType -> Maybe ([TcType], [TyVar], ThetaType, TcSigmaType)

eqType :: Type -> Type -> Bool

Type equality on source types. Does not look through newtypes or PredTypes, but it does look through type synonyms. This first checks that the kinds of the types are equal and then checks whether the types are equal, ignoring casts and coercions. (The kind check is a recursive call, but since all kinds have type Type, there is no need to check the types of kinds.) See also Note [Non-trivial definitional equality] in TyCoRep.

eqTypes :: [Type] -> [Type] -> Bool

Type equality on lists of types, looking through type synonyms but not newtypes.

nonDetCmpType :: Type -> Type -> Ordering

nonDetCmpTypes :: [Type] -> [Type] -> Ordering

eqTypeX :: RnEnv2 -> Type -> Type -> Bool

Compare types with respect to a (presumably) non-empty RnEnv2.

pickyEqType :: TcType -> TcType -> Bool

Like pickyEqTypeVis, but returns a Bool for convenience

tcEqType :: TcType -> TcType -> Bool

tcEqKind :: TcKind -> TcKind -> Bool

tcEqTypeNoKindCheck :: TcType -> TcType -> Bool

Just like tcEqType, but will return True for types of different kinds as long as their non-coercion structure is identical.

tcEqTypeVis :: TcType -> TcType -> Maybe Bool

Like tcEqType, but returns information about whether the difference is visible in the case of a mismatch. Nothing : the types are equal Just True : the types differ, and the point of difference is visible Just False : the types differ, and the point of difference is invisible

isSigmaTy :: TcType -> Bool

isRhoTy :: TcType -> Bool

isRhoExpTy :: ExpType -> Bool

Like isRhoTy, but also says True for Infer types

isOverloadedTy :: Type -> Bool

isFloatingTy :: Type -> Bool

Does a type represent a floating-point number?

isDoubleTy :: Type -> Bool

isFloatTy :: Type -> Bool

isIntTy :: Type -> Bool

isWordTy :: Type -> Bool

isStringTy :: Type -> Bool

Is a type String?

isIntegerTy :: Type -> Bool

isBoolTy :: Type -> Bool

isUnitTy :: Type -> Bool

isCharTy :: Type -> Bool

isCallStackTy :: Type -> Bool

Is a type a CallStack?

isCallStackPred :: Class -> [Type] -> Maybe FastString

Is a PredType a CallStack implicit parameter?

If so, return the name of the parameter.

hasIPPred :: PredType -> Bool

isTauTy :: Type -> Bool

isTauTyCon :: TyCon -> Bool

tcIsTyVarTy :: Type -> Bool

tcIsForAllTy :: Type -> Bool

Is this a ForAllTy with a named binder?

isPredTy :: Type -> Bool

Is the type suitable to classify a given/wanted in the typechecker?

isTyVarClassPred :: PredType -> Bool

isTyVarHead :: TcTyVar -> TcType -> Bool

Does the given tyvar appear at the head of a chain of applications (a t1 ... tn)

isInsolubleOccursCheck :: EqRel -> TcTyVar -> TcType -> Bool

Is the equality a ~r ...a.... definitely insoluble or not? a ~r Maybe a -- Definitely insoluble a ~N ...(F a)... -- Not definitely insoluble -- Perhaps (F a) reduces to Int a ~R ...(N a)... -- Not definitely insoluble -- Perhaps newtype N a = MkN Int See Note [Occurs check error] in TcCanonical for the motivation for this function.

checkValidClsArgs :: Bool -> Class -> [KindOrType] -> Bool

hasTyVarHead :: Type -> Bool

isRigidTy :: TcType -> Bool

deNoteType :: Type -> Type

orphNamesOfType :: Type -> NameSet

orphNamesOfCo :: Coercion -> NameSet

orphNamesOfTypes :: [Type] -> NameSet

orphNamesOfCoCon :: CoAxiom br -> NameSet

getDFunTyKey :: Type -> OccName

evVarPred_maybe :: EvVar -> Maybe PredType

evVarPred :: EvVar -> PredType

mkMinimalBySCs :: forall a. (a -> PredType) -> [a] -> [a]

transSuperClasses :: PredType -> [PredType]

pickQuantifiablePreds :: TyVarSet -> TcThetaType -> TcThetaType

When inferring types, should we quantify over a given predicate? Generally true of classes; generally false of equality constraints. Equality constraints that mention quantified type variables and implicit variables complicate the story. See Notes [Inheriting implicit parameters] and [Quantifying over equality constraints]

pickCapturedPreds :: TyVarSet -> TcThetaType -> TcThetaType

immSuperClasses :: Class -> [Type] -> [PredType]

isImprovementPred :: PredType -> Bool

Finding type instances

tcTyFamInsts :: Type -> [(TyCon, [Type])]

Finds outermost type-family applications occuring in a type, after expanding synonyms. In the list (F, tys) that is returned we guarantee that tys matches F's arity. For example, given type family F a :: * -> * (arity 1) calling tcTyFamInsts on (Maybe (F Int Bool) will return (F, [Int]), not (F, [Int,Bool])

This is important for its use in deciding termination of type instances (see Trac #11581). E.g. type instance G [Int] = ...(F Int type)... we don't need to take type into account when asking if the calls on the RHS are smaller than the LHS

isTyFamFree :: Type -> Bool

Check that a type does not contain any type family applications.

Finding "exact" (non-dead) type variables

exactTyCoVarsOfType :: Type -> TyCoVarSet

exactTyCoVarsOfTypes :: [Type] -> TyVarSet

candidateQTyVarsOfType :: Type -> CandidatesQTvs

Worker for splitDepVarsOfType. This might output the same var in both sets, if it's used in both a type and a kind. See Note [CandidatesQTvs determinism and order] See Note [Dependent type variables]

candidateQTyVarsOfTypes :: [Type] -> CandidatesQTvs

Like splitDepVarsOfType, but over a list of types

data CandidatesQTvs

Constructors

DV

Fields

• dv_kvs :: DTyCoVarSet
• dv_tvs :: DTyVarSet

Instances

Semigroup CandidatesQTvs

Defined in TcType

Methods

(<>) :: CandidatesQTvs -> CandidatesQTvs -> CandidatesQTvs

sconcat :: NonEmpty CandidatesQTvs -> CandidatesQTvs

stimes :: Integral b => b -> CandidatesQTvs -> CandidatesQTvs

Monoid CandidatesQTvs

Defined in TcType

Methods

mempty :: CandidatesQTvs

mappend :: CandidatesQTvs -> CandidatesQTvs -> CandidatesQTvs

mconcat :: [CandidatesQTvs] -> CandidatesQTvs

Outputable CandidatesQTvs

Defined in TcType

Methods

ppr :: CandidatesQTvs -> SDoc

pprPrec :: Rational -> CandidatesQTvs -> SDoc

anyRewritableTyVar :: Bool -> EqRel -> (EqRel -> TcTyVar -> Bool) -> TcType -> Bool

Extracting bound variables

allBoundVariables :: Type -> TyVarSet

Find all variables bound anywhere in a type. See also Note [Scope-check inferred kinds] in TcHsType

allBoundVariabless :: [Type] -> TyVarSet

isFFIArgumentTy :: DynFlags -> Safety -> Type -> Validity

isFFIImportResultTy :: DynFlags -> Type -> Validity

isFFIExportResultTy :: Type -> Validity

isFFIExternalTy :: Type -> Validity

isFFIDynTy :: Type -> Type -> Validity

isFFIPrimArgumentTy :: DynFlags -> Type -> Validity

isFFIPrimResultTy :: DynFlags -> Type -> Validity

isFFILabelTy :: Type -> Validity

isFFITy :: Type -> Bool

isFunPtrTy :: Type -> Bool

tcSplitIOType_maybe :: Type -> Maybe (TyCon, Type)

type Kind = Type

The key type representing kinds in the compiler.

typeKind :: HasDebugCallStack => Type -> Kind

liftedTypeKind :: Kind

constraintKind :: Kind

isLiftedTypeKind :: Kind -> Bool

This version considers Constraint to be distinct from *. Returns True if the argument is equivalent to Type and False otherwise.

isUnliftedTypeKind :: Kind -> Bool

Returns True if the kind classifies unlifted types and False otherwise. Note that this returns False for levity-polymorphic kinds, which may be specialized to a kind that classifies unlifted types.

classifiesTypeWithValues :: Kind -> Bool

Does this classify a type allowed to have values? Responds True to things like *, #, TYPE Lifted, TYPE v, Constraint.

True of any sub-kind of OpenTypeKind

data Type

Instances

Data Type

Defined in TyCoRep

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Type -> c Type

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Type

toConstr :: Type -> Constr

dataTypeOf :: Type -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Type)

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

gmapT :: (forall b. Data b => b -> b) -> Type -> Type

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Type -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Type -> r

gmapQ :: (forall d. Data d => d -> u) -> Type -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> Type -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Type -> m Type

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Type -> m Type

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Type -> m Type

Outputable Type

Defined in TyCoRep

Methods

ppr :: Type -> SDoc

pprPrec :: Rational -> Type -> SDoc

type PredType = Type

A type of the form p of kind Constraint represents a value whose type is the Haskell predicate p, where a predicate is what occurs before the => in a Haskell type.

We use PredType as documentation to mark those types that we guarantee to have this kind.

It can be expanded into its representation, but:

• The type checker must treat it as opaque
• The rest of the compiler treats it as transparent

Consider these examples:

f :: (Eq a) => a -> Int
g :: (?x :: Int -> Int) => a -> Int
h :: (r\l) => {r} => {l::Int | r}

Here the Eq a and ?x :: Int -> Int and rl are all called "predicates"

type ThetaType = [PredType]

A collection of PredTypes

data TyBinder

A TyBinder represents an argument to a function. TyBinders can be dependent (Named) or nondependent (Anon). They may also be visible or not. See Note [TyBinders]

Instances

Data TyBinder

Defined in TyCoRep

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> TyBinder -> c TyBinder

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c TyBinder

toConstr :: TyBinder -> Constr

dataTypeOf :: TyBinder -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c TyBinder)

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

gmapT :: (forall b. Data b => b -> b) -> TyBinder -> TyBinder

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> TyBinder -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> TyBinder -> r

gmapQ :: (forall d. Data d => d -> u) -> TyBinder -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> TyBinder -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> TyBinder -> m TyBinder

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> TyBinder -> m TyBinder

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> TyBinder -> m TyBinder

Outputable TyBinder

Defined in TyCoRep

Methods

ppr :: TyBinder -> SDoc

pprPrec :: Rational -> TyBinder -> SDoc

data ArgFlag

Argument Flag

Is something required to appear in source Haskell (Required), permitted by request (Specified) (visible type application), or prohibited entirely from appearing in source Haskell (Inferred)? See Note [TyVarBndrs, TyVarBinders, TyConBinders, and visibility] in TyCoRep

Constructors

Required

Specified

Inferred

Instances

Eq ArgFlag

Defined in Var

Methods

(==) :: ArgFlag -> ArgFlag -> Bool

(/=) :: ArgFlag -> ArgFlag -> Bool

Data ArgFlag

Defined in Var

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ArgFlag -> c ArgFlag

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ArgFlag

toConstr :: ArgFlag -> Constr

dataTypeOf :: ArgFlag -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ArgFlag)

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

gmapT :: (forall b. Data b => b -> b) -> ArgFlag -> ArgFlag

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ArgFlag -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ArgFlag -> r

gmapQ :: (forall d. Data d => d -> u) -> ArgFlag -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> ArgFlag -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> ArgFlag -> m ArgFlag

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ArgFlag -> m ArgFlag

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ArgFlag -> m ArgFlag

Outputable ArgFlag

Defined in Var

Methods

ppr :: ArgFlag -> SDoc

pprPrec :: Rational -> ArgFlag -> SDoc

Binary ArgFlag

Defined in Var

Methods

put_ :: BinHandle -> ArgFlag -> IO ()

put :: BinHandle -> ArgFlag -> IO (Bin ArgFlag)

get :: BinHandle -> IO ArgFlag

Outputable tv => Outputable (TyVarBndr tv ArgFlag)

Defined in Var

Methods

ppr :: TyVarBndr tv ArgFlag -> SDoc

pprPrec :: Rational -> TyVarBndr tv ArgFlag -> SDoc

mkForAllTy :: TyVar -> ArgFlag -> Type -> Type

mkForAllTys :: [TyVarBinder] -> Type -> Type

Wraps foralls over the type using the provided TyVars from left to right

mkInvForAllTys :: [TyVar] -> Type -> Type

Like mkForAllTys, but assumes all variables are dependent and Inferred, a common case

mkSpecForAllTys :: [TyVar] -> Type -> Type

Like mkForAllTys, but assumes all variables are dependent and specified, a common case

mkInvForAllTy :: TyVar -> Type -> Type

Make a dependent forall over an Inferred (as opposed to Specified) variable

mkFunTy :: Type -> Type -> Type infixr 3

Make an arrow type

mkFunTys :: [Type] -> Type -> Type

Make nested arrow types

mkTyConApp :: TyCon -> [Type] -> Type

A key function: builds a TyConApp or FunTy as appropriate to its arguments. Applies its arguments to the constructor from left to right.

mkAppTy :: Type -> Type -> Type

Applies a type to another, as in e.g. k a

mkAppTys :: Type -> [Type] -> Type

mkTyConTy :: TyCon -> Type

Create the plain type constructor type which has been applied to no type arguments at all.

mkTyVarTy :: TyVar -> Type

mkTyVarTys :: [TyVar] -> [Type]

isClassPred :: PredType -> Bool

isEqPred :: PredType -> Bool

isNomEqPred :: PredType -> Bool

isIPPred :: PredType -> Bool

mkClassPred :: Class -> [Type] -> PredType

isDictLikeTy :: Type -> Bool

tcSplitDFunTy :: Type -> ([TyVar], [Type], Class, [Type])

tcSplitDFunHead :: Type -> (Class, [Type])

tcSplitMethodTy :: Type -> ([TyVar], PredType, Type)

isRuntimeRepVar :: TyVar -> Bool

Is a tyvar of type RuntimeRep?

isKindLevPoly :: Kind -> Bool

Tests whether the given kind (which should look like TYPE x) is something other than a constructor tree (that is, constructors at every node).

isVisibleBinder :: TyBinder -> Bool

Does this binder bind a visible argument?

isInvisibleBinder :: TyBinder -> Bool

Does this binder bind an invisible argument?

data TCvSubst

Type & coercion substitution

The following invariants must hold of a TCvSubst:

1. The in-scope set is needed only to guide the generation of fresh uniques
2. In particular, the kind of the type variables in the in-scope set is not relevant
3. The substitution is only applied ONCE! This is because in general such application will not reach a fixed point.

Constructors

TCvSubst InScopeSet TvSubstEnv CvSubstEnv

Instances

Outputable TCvSubst

Defined in TyCoRep

Methods

ppr :: TCvSubst -> SDoc

pprPrec :: Rational -> TCvSubst -> SDoc

type TvSubstEnv = TyVarEnv Type

A substitution of Types for TyVars and Kinds for KindVars

emptyTCvSubst :: TCvSubst

zipTvSubst :: [TyVar] -> [Type] -> TCvSubst

Generates the in-scope set for the TCvSubst from the types in the incoming environment. No CoVars, please!

mkTvSubstPrs :: [(TyVar, Type)] -> TCvSubst

Generates the in-scope set for the TCvSubst from the types in the incoming environment. No CoVars, please!

notElemTCvSubst :: Var -> TCvSubst -> Bool

unionTCvSubst :: TCvSubst -> TCvSubst -> TCvSubst

getTvSubstEnv :: TCvSubst -> TvSubstEnv

setTvSubstEnv :: TCvSubst -> TvSubstEnv -> TCvSubst

getTCvInScope :: TCvSubst -> InScopeSet

extendTCvInScope :: TCvSubst -> Var -> TCvSubst

extendTCvInScopeList :: TCvSubst -> [Var] -> TCvSubst

extendTCvInScopeSet :: TCvSubst -> VarSet -> TCvSubst

extendTvSubstAndInScope :: TCvSubst -> TyVar -> Type -> TCvSubst

lookupTyVar :: TCvSubst -> TyVar -> Maybe Type

extendTCvSubst :: TCvSubst -> TyCoVar -> Type -> TCvSubst

substTyVarBndr :: HasCallStack => TCvSubst -> TyVar -> (TCvSubst, TyVar)

extendTvSubst :: TCvSubst -> TyVar -> Type -> TCvSubst

isInScope :: Var -> TCvSubst -> Bool

mkTCvSubst :: InScopeSet -> (TvSubstEnv, CvSubstEnv) -> TCvSubst

mkTvSubst :: InScopeSet -> TvSubstEnv -> TCvSubst

Make a TCvSubst with specified tyvar subst and empty covar subst

zipTyEnv :: [TyVar] -> [Type] -> TvSubstEnv

zipCoEnv :: [CoVar] -> [Coercion] -> CvSubstEnv

substTy :: HasCallStack => TCvSubst -> Type -> Type

Substitute within a Type The substitution has to satisfy the invariants described in Note [The substitution invariant].

substTys :: HasCallStack => TCvSubst -> [Type] -> [Type]

Substitute within several Types The substitution has to satisfy the invariants described in Note [The substitution invariant].

substTyWith :: HasCallStack => [TyVar] -> [Type] -> Type -> Type

Type substitution, see zipTvSubst

substTyWithCoVars :: [CoVar] -> [Coercion] -> Type -> Type

Substitute covars within a type

substTyAddInScope :: TCvSubst -> Type -> Type

Substitute within a Type after adding the free variables of the type to the in-scope set. This is useful for the case when the free variables aren't already in the in-scope set or easily available. See also Note [The substitution invariant].

substTyUnchecked :: TCvSubst -> Type -> Type

Substitute within a Type disabling the sanity checks. The problems that the sanity checks in substTy catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substTyUnchecked to substTy and remove this function. Please don't use in new code.

substTysUnchecked :: TCvSubst -> [Type] -> [Type]

Substitute within several Types disabling the sanity checks. The problems that the sanity checks in substTys catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substTysUnchecked to substTys and remove this function. Please don't use in new code.

substThetaUnchecked :: TCvSubst -> ThetaType -> ThetaType

Substitute within a ThetaType disabling the sanity checks. The problems that the sanity checks in substTys catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substThetaUnchecked to substTheta and remove this function. Please don't use in new code.

substTyWithUnchecked :: [TyVar] -> [Type] -> Type -> Type

Type substitution, see zipTvSubst. Disables sanity checks. The problems that the sanity checks in substTy catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substTyUnchecked to substTy and remove this function. Please don't use in new code.

substCoUnchecked :: TCvSubst -> Coercion -> Coercion

Substitute within a Coercion disabling sanity checks. The problems that the sanity checks in substCo catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substCoUnchecked to substCo and remove this function. Please don't use in new code.

substCoWithUnchecked :: [TyVar] -> [Type] -> Coercion -> Coercion

Coercion substitution, see zipTvSubst. Disables sanity checks. The problems that the sanity checks in substCo catch are described in Note [The substitution invariant]. The goal of #11371 is to migrate all the calls of substCoUnchecked to substCo and remove this function. Please don't use in new code.

substTheta :: HasCallStack => TCvSubst -> ThetaType -> ThetaType

Substitute within a ThetaType The substitution has to satisfy the invariants described in Note [The substitution invariant].

isUnliftedType :: HasDebugCallStack => Type -> Bool

See Type for what an unlifted type is. Panics on levity polymorphic types.

isUnboxedTupleType :: Type -> Bool

isPrimitiveType :: Type -> Bool

Returns true of types that are opaque to Haskell.

tcView :: Type -> Maybe Type

Gives the typechecker view of a type. This unwraps synonyms but leaves Constraint alone. c.f. coreView, which turns Constraint into TYPE LiftedRep. Returns Nothing if no unwrapping happens. See also Note [coreView vs tcView] in Type.

coreView :: Type -> Maybe Type

This function Strips off the top layer only of a type synonym application (if any) its underlying representation type. Returns Nothing if there is nothing to look through. This function considers Constraint to be a synonym of TYPE LiftedRep.

By being non-recursive and inlined, this case analysis gets efficiently joined onto the case analysis that the caller is already doing

tyCoVarsOfType :: Type -> TyCoVarSet

Returns free variables of a type, including kind variables as a non-deterministic set. For type synonyms it does not expand the synonym.

tyCoVarsOfTypes :: [Type] -> TyCoVarSet

Returns free variables of types, including kind variables as a non-deterministic set. For type synonyms it does not expand the synonym.

closeOverKinds :: TyVarSet -> TyVarSet

Add the kind variables free in the kinds of the tyvars in the given set. Returns a non-deterministic set.

tyCoFVsOfType :: Type -> FV

The worker for tyCoFVsOfType and tyCoFVsOfTypeList. The previous implementation used unionVarSet which is O(n+m) and can make the function quadratic. It's exported, so that it can be composed with other functions that compute free variables. See Note [FV naming conventions] in FV.

Eta-expanded because that makes it run faster (apparently) See Note [FV eta expansion] in FV for explanation.

tyCoFVsOfTypes :: [Type] -> FV

tyCoVarsOfTypeDSet :: Type -> DTyCoVarSet

tyCoFVsOfType that returns free variables of a type in a deterministic set. For explanation of why using VarSet is not deterministic see Note [Deterministic FV] in FV.

tyCoVarsOfTypesDSet :: [Type] -> DTyCoVarSet

Returns free variables of types, including kind variables as a deterministic set. For type synonyms it does not expand the synonym.

closeOverKindsDSet :: DTyVarSet -> DTyVarSet

Add the kind variables free in the kinds of the tyvars in the given set. Returns a deterministic set.

tyCoVarsOfTypeList :: Type -> [TyCoVar]

tyCoFVsOfType that returns free variables of a type in deterministic order. For explanation of why using VarSet is not deterministic see Note [Deterministic FV] in FV.

tyCoVarsOfTypesList :: [Type] -> [TyCoVar]

Returns free variables of types, including kind variables as a deterministically ordered list. For type synonyms it does not expand the synonym.

noFreeVarsOfType :: Type -> Bool

Returns True if this type has no free variables. Should be the same as isEmptyVarSet . tyCoVarsOfType, but faster in the non-forall case.

toTcType :: Type -> TcType

toTcTypeBag :: Bag EvVar -> Bag EvVar

pprKind :: Kind -> SDoc

pprParendKind :: Kind -> SDoc

pprSigmaType :: Type -> SDoc

pprType :: Type -> SDoc

pprParendType :: Type -> SDoc

pprTypeApp :: TyCon -> [Type] -> SDoc

pprTyThingCategory :: TyThing -> SDoc

tyThingCategory :: TyThing -> String

pprTheta :: ThetaType -> SDoc

pprParendTheta :: ThetaType -> SDoc

pprThetaArrowTy :: ThetaType -> SDoc

pprClassPred :: Class -> [Type] -> SDoc

pprTvBndr :: TyVarBinder -> SDoc

pprTvBndrs :: [TyVarBinder] -> SDoc

type TypeSize = IntWithInf

sizeType :: Type -> TypeSize

sizeTypes :: [Type] -> TypeSize

toposortTyVars :: [TyCoVar] -> [TyCoVar]

Do a topological sort on a list of tyvars, so that binders occur before occurrences E.g. given [ a::k, k::*, b::k ] it'll return a well-scoped list [ k::*, a::k, b::k ]

This is a deterministic sorting operation (that is, doesn't depend on Uniques).

tcTyConVisibilities :: TyCon -> [Bool]

For every arg a tycon can take, the returned list says True if the argument is taken visibly, and False otherwise. Ends with an infinite tail of Trues to allow for oversaturation.

isNextTyConArgVisible :: TyCon -> [Type] -> Bool

If the tycon is applied to the types, is the next argument visible?

isNextArgVisible :: TcType -> Bool

Should this type be applied to a visible argument?