GHC.Tc.Solver.Monad

Monadic definitions for the constraint solver

Documentation

data TcS a Source #

Instances
Instances details
MonadFail TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

fail :: String -> TcS a Source #

MonadIO TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

liftIO :: IO a -> TcS a Source #

Applicative TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

pure :: a -> TcS a Source #

(<*>) :: TcS (a -> b) -> TcS a -> TcS b Source #

liftA2 :: (a -> b -> c) -> TcS a -> TcS b -> TcS c Source #

(*>) :: TcS a -> TcS b -> TcS b Source #

(<*) :: TcS a -> TcS b -> TcS a Source #

Functor TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

fmap :: (a -> b) -> TcS a -> TcS b Source #

(<$) :: a -> TcS b -> TcS a Source #

Monad TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

(>>=) :: TcS a -> (a -> TcS b) -> TcS b Source #

(>>) :: TcS a -> TcS b -> TcS b Source #

return :: a -> TcS a Source #

HasDynFlags TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

getDynFlags :: TcS DynFlags Source #

MonadThings TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

lookupThing :: Name -> TcS TyThing Source #

lookupId :: Name -> TcS Id Source #

lookupDataCon :: Name -> TcS DataCon Source #

lookupTyCon :: Name -> TcS TyCon Source #

MonadUnique TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

getUniqueSupplyM :: TcS UniqSupply Source #

getUniqueM :: TcS Unique Source #

getUniquesM :: TcS [Unique] Source #

HasModule TcS Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

getModule :: TcS Module Source #

runTcS :: TcS a -> TcM (a, EvBindMap) Source #

runTcSEarlyAbort :: TcS a -> TcM a Source #

This variant of runTcS will immediatley fail upon encountering an insoluble ct. See Note [Speeding up valid hole-fits]. Its one usage site does not need the ev_binds, so we do not return them.

runTcSWithEvBinds :: EvBindsVar -> TcS a -> TcM a Source #

runTcSInerts :: InertSet -> TcS a -> TcM (a, InertSet) Source #

A variant of runTcS that takes and returns an InertSet for later resumption of the TcS session.

failTcS :: TcRnMessage -> TcS a Source #

warnTcS :: TcRnMessage -> TcS () Source #

addErrTcS :: TcRnMessage -> TcS () Source #

wrapTcS :: TcM a -> TcS a Source #

runTcSEqualities :: TcS a -> TcM a Source #

This can deal only with equality constraints.

nestTcS :: TcS a -> TcS a Source #

nestImplicTcS :: EvBindsVar -> TcLevel -> TcS a -> TcS a Source #

setEvBindsTcS :: EvBindsVar -> TcS a -> TcS a Source #

emitImplicationTcS :: TcLevel -> SkolemInfoAnon -> [TcTyVar] -> [EvVar] -> Cts -> TcS TcEvBinds Source #

emitTvImplicationTcS :: TcLevel -> SkolemInfoAnon -> [TcTyVar] -> Cts -> TcS () Source #

selectNextWorkItem :: TcS (Maybe Ct) Source #

getWorkList :: TcS WorkList Source #

updWorkListTcS :: (WorkList -> WorkList) -> TcS () Source #

pushLevelNoWorkList :: SDoc -> TcS a -> TcS (TcLevel, a) Source #

runTcPluginTcS :: TcPluginM a -> TcS a Source #

addUsedGRE :: Bool -> GlobalRdrElt -> TcS () Source #

addUsedGREs :: [GlobalRdrElt] -> TcS () Source #

keepAlive :: Name -> TcS () Source #

matchGlobalInst :: DynFlags -> Bool -> Class -> [Type] -> TcS ClsInstResult Source #

data ClsInstResult Source #

Constructors

NoInstance 
OneInst 

Fields

NotSure 
Instances
Instances details
Outputable ClsInstResult Source # 
Instance details

Defined in GHC.Tc.Instance.Class

Methods

ppr :: ClsInstResult -> SDoc Source #

data QCInst Source #

Constructors

QCI 

Fields

Instances
Instances details
Outputable QCInst Source # 
Instance details

Defined in GHC.Tc.Types.Constraint

Methods

ppr :: QCInst -> SDoc Source #

panicTcS :: SDoc -> TcS a Source #

traceTcS :: String -> SDoc -> TcS () Source #

traceFireTcS :: CtEvidence -> SDoc -> TcS () Source #

bumpStepCountTcS :: TcS () Source #

csTraceTcS :: SDoc -> TcS () Source #

wrapErrTcS :: TcM a -> TcS a Source #

wrapWarnTcS :: TcM a -> TcS a Source #

resetUnificationFlag :: TcS Bool Source #

setUnificationFlag :: TcLevel -> TcS () Source #

data MaybeNew Source #

Constructors

Fresh CtEvidence 
Cached EvExpr 

freshGoals :: [MaybeNew] -> [CtEvidence] Source #

isFresh :: MaybeNew -> Bool Source #

getEvExpr :: MaybeNew -> EvExpr Source #

newTcEvBinds :: TcS EvBindsVar Source #

newNoTcEvBinds :: TcS EvBindsVar Source #

newWantedEq :: CtLoc -> RewriterSet -> Role -> TcType -> TcType -> TcS (CtEvidence, Coercion) Source #

Create a new Wanted constraint holding a coercion hole for an equality between the two types at the given Role.

emitNewWantedEq :: CtLoc -> RewriterSet -> Role -> TcType -> TcType -> TcS Coercion Source #

Emit a new Wanted equality into the work-list

newWanted :: CtLoc -> RewriterSet -> PredType -> TcS MaybeNew Source #

Create a new Wanted constraint, potentially looking up non-equality constraints in the cache instead of creating a new one from scratch.

Deals with both equality and non-equality constraints.

newWantedNC :: CtLoc -> RewriterSet -> PredType -> TcS CtEvidence Source #

Create a new Wanted constraint.

Deals with both equality and non-equality constraints.

Does not attempt to re-use non-equality constraints that already exist in the inert set.

newWantedEvVarNC :: CtLoc -> RewriterSet -> TcPredType -> TcS CtEvidence Source #

Create a new Wanted constraint holding an evidence variable.

Don't use this for equality constraints: use newWantedEq instead.

newBoundEvVarId :: TcPredType -> EvTerm -> TcS EvVar Source #

Make a new Id of the given type, bound (in the monad's EvBinds) to the given term

unifyTyVar :: TcTyVar -> TcType -> TcS () Source #

reportUnifications :: TcS a -> TcS (Int, a) Source #

touchabilityTest :: CtFlavour -> TcTyVar -> TcType -> TcS (TouchabilityTestResult, TcType) Source #

This is the key test for untouchability: See Note [Unification preconditions] in GHC.Tc.Utils.Unify and Note [Solve by unification] in GHC.Tc.Solver.Interact

Returns a new rhs type, as this function can turn make some metavariables concrete.

data TouchabilityTestResult Source #

Constructors

TouchableSameLevel 
TouchableOuterLevel [TcTyVar] TcLevel 
Untouchable 
Instances
Instances details
Outputable TouchabilityTestResult Source # 
Instance details

Defined in GHC.Tc.Solver.Monad

Methods

ppr :: TouchabilityTestResult -> SDoc Source #

setEvBind :: EvBind -> TcS () Source #

setWantedEq :: HasDebugCallStack => TcEvDest -> Coercion -> TcS () Source #

Equalities only

setWantedEvTerm :: TcEvDest -> EvTerm -> TcS () Source #

Good for both equalities and non-equalities

setEvBindIfWanted :: CtEvidence -> EvTerm -> TcS () Source #

newEvVar :: TcPredType -> TcS EvVar Source #

newGivenEvVar :: CtLoc -> (TcPredType, EvTerm) -> TcS CtEvidence Source #

newGivenEvVars :: CtLoc -> [(TcPredType, EvTerm)] -> TcS [CtEvidence] Source #

checkReductionDepth Source #

Arguments

:: CtLoc 
-> TcType

type being reduced

-> TcS () 

Checks if the depth of the given location is too much. Fails if it's too big, with an appropriate error message.

getSolvedDicts :: TcS (DictMap CtEvidence) Source #

setSolvedDicts :: DictMap CtEvidence -> TcS () Source #

getInstEnvs :: TcS InstEnvs Source #

getFamInstEnvs :: TcS (FamInstEnv, FamInstEnv) Source #

getTopEnv :: TcS HscEnv Source #

getGblEnv :: TcS TcGblEnv Source #

getLclEnv :: TcS TcLclEnv Source #

setLclEnv :: TcLclEnv -> TcS a -> TcS a Source #

getTcEvBindsVar :: TcS EvBindsVar Source #

getTcLevel :: TcS TcLevel Source #

getTcEvTyCoVars :: EvBindsVar -> TcS TyCoVarSet Source #

getTcEvBindsMap :: EvBindsVar -> TcS EvBindMap Source #

setTcEvBindsMap :: EvBindsVar -> EvBindMap -> TcS () Source #

tcLookupClass :: Name -> TcS Class Source #

tcLookupId :: Name -> TcS Id Source #

updInertTcS :: (InertSet -> InertSet) -> TcS () Source #

updInertCans :: (InertCans -> InertCans) -> TcS () Source #

updInertDicts :: (DictMap Ct -> DictMap Ct) -> TcS () Source #

updInertIrreds :: (Cts -> Cts) -> TcS () Source #

getHasGivenEqs :: TcLevel -> TcS (HasGivenEqs, Cts) Source #

setInertCans :: InertCans -> TcS () Source #

getInertEqs :: TcS InertEqs Source #

getInertCans :: TcS InertCans Source #

getInertGivens :: TcS [Ct] Source #

getInertInsols :: TcS Cts Source #

getInnermostGivenEqLevel :: TcS TcLevel Source #

getTcSInerts :: TcS InertSet Source #

setTcSInerts :: InertSet -> TcS () Source #

getUnsolvedInerts :: TcS (Bag Implication, Cts) Source #

removeInertCts :: [Ct] -> InertCans -> InertCans Source #

Remove inert constraints from the InertCans, for use when a typechecker plugin wishes to discard a given.

getPendingGivenScs :: TcS [Ct] Source #

addInertCan :: Ct -> TcS () Source #

insertFunEq :: FunEqMap a -> TyCon -> [Type] -> a -> FunEqMap a Source #

addInertForAll :: QCInst -> TcS () Source #

emitWorkNC :: [CtEvidence] -> TcS () Source #

emitWork :: [Ct] -> TcS () Source #

lookupInertDict :: InertCans -> CtLoc -> Class -> [Type] -> Maybe Ct Source #

Look up a dictionary inert.

kickOutAfterUnification :: TcTyVar -> TcS Int Source #

addInertSafehask :: InertCans -> Ct -> InertCans Source #

insertSafeOverlapFailureTcS :: InstanceWhat -> Ct -> TcS () Source #

updInertSafehask :: (DictMap Ct -> DictMap Ct) -> TcS () Source #

getSafeOverlapFailures :: TcS Cts Source #

addSolvedDict :: InstanceWhat -> CtEvidence -> Class -> [Type] -> TcS () Source #

lookupSolvedDict :: InertSet -> CtLoc -> Class -> [Type] -> Maybe CtEvidence Source #

Look up a solved inert.

foldIrreds :: (Ct -> b -> b) -> Cts -> b -> b Source #

lookupFamAppInert :: (CtFlavourRole -> Bool) -> TyCon -> [Type] -> TcS (Maybe (Reduction, CtFlavourRole)) Source #

Looks up a family application in the inerts.

lookupFamAppCache :: TyCon -> [Type] -> TcS (Maybe Reduction) Source #

extendFamAppCache :: TyCon -> [Type] -> Reduction -> TcS () Source #

pprKicked :: Int -> SDoc Source #

instDFunType :: DFunId -> [DFunInstType] -> TcS ([TcType], TcThetaType) Source #

newFlexiTcSTy :: Kind -> TcS TcType Source #

instFlexi :: [TKVar] -> TcS TCvSubst Source #

instFlexiX :: TCvSubst -> [TKVar] -> TcS TCvSubst Source #

cloneMetaTyVar :: TcTyVar -> TcS TcTyVar Source #

tcInstSkolTyVarsX :: SkolemInfo -> TCvSubst -> [TyVar] -> TcS (TCvSubst, [TcTyVar]) Source #

data TcLevel Source #

Instances
Instances details
Outputable TcLevel Source # 
Instance details

Defined in GHC.Tc.Utils.TcType

Methods

ppr :: TcLevel -> SDoc Source #

Eq TcLevel Source # 
Instance details

Defined in GHC.Tc.Utils.TcType

Methods

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

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

Ord TcLevel Source # 
Instance details

Defined in GHC.Tc.Utils.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 #

isFilledMetaTyVar_maybe :: TcTyVar -> TcS (Maybe Type) Source #

isFilledMetaTyVar :: TcTyVar -> TcS Bool Source #

zonkTyCoVarsAndFV :: TcTyCoVarSet -> TcS TcTyCoVarSet Source #

zonkTcType :: TcType -> TcS TcType Source #

zonkTcTypes :: [TcType] -> TcS [TcType] Source #

zonkTcTyVar :: TcTyVar -> TcS TcType Source #

zonkCo :: Coercion -> TcS Coercion Source #

zonkTyCoVarsAndFVList :: [TcTyCoVar] -> TcS [TcTyCoVar] Source #

zonkSimples :: Cts -> TcS Cts Source #

zonkWC :: WantedConstraints -> TcS WantedConstraints Source #

zonkTyCoVarKind :: TcTyCoVar -> TcS TcTyCoVar Source #

newTcRef :: a -> TcS (TcRef a) Source #

readTcRef :: TcRef a -> TcS a Source #

writeTcRef :: TcRef a -> a -> TcS () Source #

updTcRef :: TcRef a -> (a -> a) -> TcS () Source #

getDefaultInfo :: TcS ([Type], (Bool, Bool)) Source #

getDynFlags :: HasDynFlags m => m DynFlags Source #

getGlobalRdrEnvTcS :: TcS GlobalRdrEnv Source #

matchFam :: TyCon -> [Type] -> TcS (Maybe ReductionN) Source #

matchFamTcM :: TyCon -> [Type] -> TcM (Maybe ReductionN) Source #

checkWellStagedDFun :: CtLoc -> InstanceWhat -> PredType -> TcS () Source #

pprEq :: TcType -> TcType -> SDoc Source #

breakTyEqCycle_maybe :: CtEvidence -> CheckTyEqResult -> CanEqLHS -> TcType -> TcS (Maybe ReductionN) Source #

Conditionally replace all type family applications in the RHS with fresh variables, emitting givens that relate the type family application to the variable. See Note [Type equality cycles] in GHC.Tc.Solver.Canonical. This only works under conditions as described in the Note; otherwise, returns Nothing.

rewriterView :: TcType -> Maybe TcType Source #