Safe Haskell	Safe-Inferred
Language	Haskell2010

GHC.Tc.Utils.Unify

Description

Type subsumption and unification

Synopsis

tcWrapResult :: HsExpr GhcRn -> HsExpr GhcTc -> TcSigmaType -> ExpRhoType -> TcM (HsExpr GhcTc)
tcWrapResultO :: CtOrigin -> HsExpr GhcRn -> HsExpr GhcTc -> TcSigmaType -> ExpRhoType -> TcM (HsExpr GhcTc)
tcWrapResultMono :: HsExpr GhcRn -> HsExpr GhcTc -> TcRhoType -> ExpRhoType -> TcM (HsExpr GhcTc)
tcSkolemise :: UserTypeCtxt -> TcSigmaType -> (TcType -> TcM result) -> TcM (HsWrapper, result)
tcSkolemiseScoped :: UserTypeCtxt -> TcSigmaType -> (TcType -> TcM result) -> TcM (HsWrapper, result)
tcSkolemiseET :: UserTypeCtxt -> ExpSigmaType -> (ExpRhoType -> TcM result) -> TcM (HsWrapper, result)
tcSubType :: CtOrigin -> UserTypeCtxt -> TcSigmaType -> ExpRhoType -> TcM HsWrapper
tcSubTypeSigma :: UserTypeCtxt -> TcSigmaType -> TcSigmaType -> TcM HsWrapper
tcSubTypePat :: CtOrigin -> UserTypeCtxt -> ExpSigmaType -> TcSigmaType -> TcM HsWrapper
tcSubMult :: CtOrigin -> Mult -> Mult -> TcM HsWrapper
checkConstraints :: SkolemInfo -> [TcTyVar] -> [EvVar] -> TcM result -> TcM (TcEvBinds, result)
checkTvConstraints :: SkolemInfo -> [TcTyVar] -> TcM result -> TcM result
buildImplicationFor :: TcLevel -> SkolemInfo -> [TcTyVar] -> [EvVar] -> WantedConstraints -> TcM (Bag Implication, TcEvBinds)
buildTvImplication :: SkolemInfo -> [TcTyVar] -> TcLevel -> WantedConstraints -> TcM Implication
emitResidualTvConstraint :: SkolemInfo -> [TcTyVar] -> TcLevel -> WantedConstraints -> TcM ()
unifyType :: Maybe SDoc -> TcTauType -> TcTauType -> TcM TcCoercionN
unifyKind :: Maybe SDoc -> TcKind -> TcKind -> TcM CoercionN
unifyExpectedType :: HsExpr GhcRn -> TcRhoType -> ExpRhoType -> TcM TcCoercionN
uType :: TypeOrKind -> CtOrigin -> TcType -> TcType -> TcM CoercionN
promoteTcType :: TcLevel -> TcType -> TcM (TcCoercionN, TcType)
swapOverTyVars :: Bool -> TcTyVar -> TcTyVar -> Bool
canSolveByUnification :: MetaInfo -> TcType -> Bool
tcInfer :: (ExpSigmaType -> TcM a) -> TcM (a, TcSigmaType)
matchExpectedListTy :: TcRhoType -> TcM (TcCoercionN, TcRhoType)
matchExpectedTyConApp :: TyCon -> TcRhoType -> TcM (TcCoercionN, [TcSigmaType])
matchExpectedAppTy :: TcRhoType -> TcM (TcCoercion, (TcSigmaType, TcSigmaType))
matchExpectedFunTys :: forall a. SDoc -> UserTypeCtxt -> Arity -> ExpRhoType -> ([Scaled ExpSigmaType] -> ExpRhoType -> TcM a) -> TcM (HsWrapper, a)
matchExpectedFunKind :: Outputable fun => fun -> Arity -> TcKind -> TcM Coercion
matchActualFunTySigma :: SDoc -> Maybe SDoc -> (Arity, [Scaled TcSigmaType]) -> TcRhoType -> TcM (HsWrapper, Scaled TcSigmaType, TcSigmaType)
matchActualFunTysRho :: SDoc -> CtOrigin -> Maybe SDoc -> Arity -> TcSigmaType -> TcM (HsWrapper, [Scaled TcSigmaType], TcRhoType)
occCheckForErrors :: DynFlags -> TcTyVar -> Type -> CheckTyEqResult
data CheckTyEqResult
- = CTE_OK
- | CTE_Bad
- | CTE_HoleBlocker
- | CTE_Occurs
checkTyVarEq :: DynFlags -> AreTypeFamiliesOK -> TcTyVar -> TcType -> CheckTyEqResult
checkTyFamEq :: DynFlags -> TyCon -> [TcType] -> TcType -> CheckTyEqResult
checkTypeEq :: DynFlags -> AreTypeFamiliesOK -> CanEqLHS -> TcType -> CheckTyEqResult
data AreTypeFamiliesOK
- = YesTypeFamilies
- | NoTypeFamilies

Documentation

tcWrapResult :: HsExpr GhcRn -> HsExpr GhcTc -> TcSigmaType -> ExpRhoType -> TcM (HsExpr GhcTc) Source #

tcWrapResultO :: CtOrigin -> HsExpr GhcRn -> HsExpr GhcTc -> TcSigmaType -> ExpRhoType -> TcM (HsExpr GhcTc) Source #

tcWrapResultMono :: HsExpr GhcRn -> HsExpr GhcTc -> TcRhoType -> ExpRhoType -> TcM (HsExpr GhcTc) Source #

tcSkolemise Source #

Arguments

:: UserTypeCtxt
-> TcSigmaType
-> (TcType -> TcM result)
-> TcM (HsWrapper, result)	The wrapper has type: spec_ty ~> expected_ty See Note [Skolemisation] for the differences between tcSkolemiseScoped and tcSkolemise

tcSkolemiseScoped Source #

Arguments

:: UserTypeCtxt
-> TcSigmaType
-> (TcType -> TcM result)
-> TcM (HsWrapper, result)	The wrapper has type: spec_ty ~> expected_ty See Note [Skolemisation] for the differences between tcSkolemiseScoped and tcSkolemise

tcSkolemiseET :: UserTypeCtxt -> ExpSigmaType -> (ExpRhoType -> TcM result) -> TcM (HsWrapper, result) Source #

Variant of tcSkolemise that takes an ExpType

tcSubType :: CtOrigin -> UserTypeCtxt -> TcSigmaType -> ExpRhoType -> TcM HsWrapper Source #

tcSubTypeSigma :: UserTypeCtxt -> TcSigmaType -> TcSigmaType -> TcM HsWrapper Source #

tcSubTypePat :: CtOrigin -> UserTypeCtxt -> ExpSigmaType -> TcSigmaType -> TcM HsWrapper Source #

tcSubMult :: CtOrigin -> Mult -> Mult -> TcM HsWrapper Source #

checkConstraints :: SkolemInfo -> [TcTyVar] -> [EvVar] -> TcM result -> TcM (TcEvBinds, result) Source #

checkTvConstraints :: SkolemInfo -> [TcTyVar] -> TcM result -> TcM result Source #

buildImplicationFor :: TcLevel -> SkolemInfo -> [TcTyVar] -> [EvVar] -> WantedConstraints -> TcM (Bag Implication, TcEvBinds) Source #

buildTvImplication :: SkolemInfo -> [TcTyVar] -> TcLevel -> WantedConstraints -> TcM Implication Source #

emitResidualTvConstraint :: SkolemInfo -> [TcTyVar] -> TcLevel -> WantedConstraints -> TcM () Source #

unifyType Source #

Arguments

:: Maybe SDoc	If present, the thing that has type ty1
-> TcTauType
-> TcTauType
-> TcM TcCoercionN

unifyKind :: Maybe SDoc -> TcKind -> TcKind -> TcM CoercionN Source #

unifyExpectedType :: HsExpr GhcRn -> TcRhoType -> ExpRhoType -> TcM TcCoercionN Source #

uType :: TypeOrKind -> CtOrigin -> TcType -> TcType -> TcM CoercionN Source #

promoteTcType :: TcLevel -> TcType -> TcM (TcCoercionN, TcType) Source #

swapOverTyVars :: Bool -> TcTyVar -> TcTyVar -> Bool Source #

canSolveByUnification :: MetaInfo -> TcType -> Bool Source #

tcInfer :: (ExpSigmaType -> TcM a) -> TcM (a, TcSigmaType) Source #

Infer a type using a fresh ExpType See also Note [ExpType] in GHC.Tc.Utils.TcMType

matchExpectedListTy :: TcRhoType -> TcM (TcCoercionN, TcRhoType) Source #

matchExpectedTyConApp :: TyCon -> TcRhoType -> TcM (TcCoercionN, [TcSigmaType]) Source #

matchExpectedAppTy :: TcRhoType -> TcM (TcCoercion, (TcSigmaType, TcSigmaType)) Source #

matchExpectedFunTys :: forall a. SDoc -> UserTypeCtxt -> Arity -> ExpRhoType -> ([Scaled ExpSigmaType] -> ExpRhoType -> TcM a) -> TcM (HsWrapper, a) Source #

matchExpectedFunKind Source #

Arguments

:: Outputable fun
=> fun	type, only for errors
-> Arity	n: number of desired arrows
-> TcKind	fun_ kind
-> TcM Coercion	co :: fun_kind ~ (arg1 -> ... -> argn -> res)

Breaks apart a function kind into its pieces.

matchActualFunTySigma :: SDoc -> Maybe SDoc -> (Arity, [Scaled TcSigmaType]) -> TcRhoType -> TcM (HsWrapper, Scaled TcSigmaType, TcSigmaType) Source #

matchActualFunTySigma does looks for just one function arrow returning an uninstantiated sigma-type

matchActualFunTysRho :: SDoc -> CtOrigin -> Maybe SDoc -> Arity -> TcSigmaType -> TcM (HsWrapper, [Scaled TcSigmaType], TcRhoType) Source #

occCheckForErrors :: DynFlags -> TcTyVar -> Type -> CheckTyEqResult Source #

data CheckTyEqResult Source #

Constructors

CTE_OK
CTE_Bad
CTE_HoleBlocker
CTE_Occurs

Instances

Instances details

Monoid CheckTyEqResult #
Instance details Defined in GHC.Tc.Utils.Unify Methods mempty :: CheckTyEqResult Source # mappend :: CheckTyEqResult -> CheckTyEqResult -> CheckTyEqResult Source # mconcat :: [CheckTyEqResult] -> CheckTyEqResult Source #
Semigroup CheckTyEqResult #
Instance details Defined in GHC.Tc.Utils.Unify Methods (<>) :: CheckTyEqResult -> CheckTyEqResult -> CheckTyEqResult Source # sconcat :: NonEmpty CheckTyEqResult -> CheckTyEqResult Source # stimes :: Integral b => b -> CheckTyEqResult -> CheckTyEqResult Source #
Outputable CheckTyEqResult #
Instance details Defined in GHC.Tc.Utils.Unify Methods ppr :: CheckTyEqResult -> SDoc Source #

checkTyVarEq :: DynFlags -> AreTypeFamiliesOK -> TcTyVar -> TcType -> CheckTyEqResult Source #

checkTyFamEq :: DynFlags -> TyCon -> [TcType] -> TcType -> CheckTyEqResult Source #

checkTypeEq :: DynFlags -> AreTypeFamiliesOK -> CanEqLHS -> TcType -> CheckTyEqResult Source #

data AreTypeFamiliesOK Source #

Constructors

YesTypeFamilies
NoTypeFamilies

Instances

Instances details

Outputable AreTypeFamiliesOK #
Instance details Defined in GHC.Tc.Utils.Unify Methods ppr :: AreTypeFamiliesOK -> SDoc Source #
Eq AreTypeFamiliesOK #
Instance details Defined in GHC.Tc.Utils.Unify Methods (==) :: AreTypeFamiliesOK -> AreTypeFamiliesOK -> Bool # (/=) :: AreTypeFamiliesOK -> AreTypeFamiliesOK -> Bool #