GHC.Tc.Utils.Monad

Functions for working with the typechecker environment (setters, getters...).

Initialisation

initTc :: HscEnv -> HscSource -> Bool -> Module -> RealSrcSpan -> TcM r -> IO (Messages TcRnMessage, Maybe r)

Setup the initial typechecking environment

initTcWithGbl :: HscEnv -> TcGblEnv -> RealSrcSpan -> TcM r -> IO (Messages TcRnMessage, Maybe r)

Run a TcM action in the context of an existing GblEnv.

initTcInteractive :: HscEnv -> TcM a -> IO (Messages TcRnMessage, Maybe a)

initTcRnIf

Arguments

:: Char

Mask for unique supply

-> HscEnv

-> gbl

-> lcl

-> TcRnIf gbl lcl a

-> IO a

Simple accessors

discardResult :: TcM a -> TcM ()

getTopEnv :: TcRnIf gbl lcl HscEnv

updTopEnv :: (HscEnv -> HscEnv) -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

getGblEnv :: TcRnIf gbl lcl gbl

updGblEnv :: (gbl -> gbl) -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

setGblEnv :: gbl' -> TcRnIf gbl' lcl a -> TcRnIf gbl lcl a

getLclEnv :: TcRnIf gbl lcl lcl

updLclEnv :: (lcl -> lcl) -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

setLclEnv :: lcl' -> TcRnIf gbl lcl' a -> TcRnIf gbl lcl a

restoreLclEnv :: TcLclEnv -> TcRnIf gbl TcLclEnv a -> TcRnIf gbl TcLclEnv a

updTopFlags :: (DynFlags -> DynFlags) -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

getEnvs :: TcRnIf gbl lcl (gbl, lcl)

setEnvs :: (gbl', lcl') -> TcRnIf gbl' lcl' a -> TcRnIf gbl lcl a

updEnvs :: ((gbl, lcl) -> (gbl, lcl)) -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

restoreEnvs :: (TcGblEnv, TcLclEnv) -> TcRn a -> TcRn a

xoptM :: Extension -> TcRnIf gbl lcl Bool

doptM :: DumpFlag -> TcRnIf gbl lcl Bool

goptM :: GeneralFlag -> TcRnIf gbl lcl Bool

woptM :: WarningFlag -> TcRnIf gbl lcl Bool

setXOptM :: Extension -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

unsetXOptM :: Extension -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

unsetGOptM :: GeneralFlag -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

unsetWOptM :: WarningFlag -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a

whenDOptM :: DumpFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()

Do it flag is true

whenGOptM :: GeneralFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()

whenWOptM :: WarningFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()

whenXOptM :: Extension -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()

unlessXOptM :: Extension -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()

getGhcMode :: TcRnIf gbl lcl GhcMode

withoutDynamicNow :: TcRnIf gbl lcl a -> TcRnIf gbl lcl a

getEpsVar :: TcRnIf gbl lcl (TcRef ExternalPackageState)

getEps :: TcRnIf gbl lcl ExternalPackageState

updateEps :: (ExternalPackageState -> (ExternalPackageState, a)) -> TcRnIf gbl lcl a

Update the external package state. Returns the second result of the modifier function.

This is an atomic operation and forces evaluation of the modified EPS in order to avoid space leaks.

updateEps_ :: (ExternalPackageState -> ExternalPackageState) -> TcRnIf gbl lcl ()

Update the external package state.

This is an atomic operation and forces evaluation of the modified EPS in order to avoid space leaks.

getHpt :: TcRnIf gbl lcl HomePackageTable

getEpsAndHug :: TcRnIf gbl lcl (ExternalPackageState, HomeUnitGraph)

Arrow scopes

newArrowScope :: TcM a -> TcM a

escapeArrowScope :: TcM a -> TcM a

Unique supply

newUnique :: TcRnIf gbl lcl Unique

newUniqueSupply :: TcRnIf gbl lcl UniqSupply

newName :: OccName -> TcM Name

newNameAt :: OccName -> SrcSpan -> TcM Name

cloneLocalName :: Name -> TcM Name

newSysName :: OccName -> TcRnIf gbl lcl Name

newSysLocalId :: FastString -> Mult -> TcType -> TcRnIf gbl lcl TcId

newSysLocalIds :: FastString -> [Scaled TcType] -> TcRnIf gbl lcl [TcId]

Accessing input/output

newTcRef :: a -> TcRnIf gbl lcl (TcRef a)

readTcRef :: TcRef a -> TcRnIf gbl lcl a

writeTcRef :: TcRef a -> a -> TcRnIf gbl lcl ()

updTcRef :: TcRef a -> (a -> a) -> TcRnIf gbl lcl ()

Debugging

traceTc :: String -> SDoc -> TcRn ()

traceRn :: String -> SDoc -> TcRn ()

traceOptTcRn :: DumpFlag -> SDoc -> TcRn ()

dumpOptTcRn :: DumpFlag -> String -> DumpFormat -> SDoc -> TcRn ()

Dump if the given DumpFlag is set.

dumpTcRn :: Bool -> DumpFlag -> String -> DumpFormat -> SDoc -> TcRn ()

Unconditionally dump some trace output

Certain tests (T3017, Roles3, T12763 etc.) expect part of the output generated by `-ddump-types` to be in PprUser style. However, generally we want all other debugging output to use PprDump style. We PprUser style if useUserStyle is True.

getPrintUnqualified :: TcRn PrintUnqualified

printForUserTcRn :: SDoc -> TcRn ()

Like logInfoTcRn, but for user consumption

traceIf :: SDoc -> TcRnIf m n ()

traceOptIf :: DumpFlag -> SDoc -> TcRnIf m n ()

debugTc :: TcM () -> TcM ()

Typechecker global environment

getIsGHCi :: TcRn Bool

getGHCiMonad :: TcRn Name

getInteractivePrintName :: TcRn Name

tcIsHsBootOrSig :: TcRn Bool

tcIsHsig :: TcRn Bool

tcSelfBootInfo :: TcRn SelfBootInfo

getGlobalRdrEnv :: TcRn GlobalRdrEnv

getRdrEnvs :: TcRn (GlobalRdrEnv, LocalRdrEnv)

getImports :: TcRn ImportAvails

getFixityEnv :: TcRn FixityEnv

extendFixityEnv :: [(Name, FixItem)] -> RnM a -> RnM a

getRecFieldEnv :: TcRn RecFieldEnv

getDeclaredDefaultTys :: TcRn (Maybe [Type])

addDependentFiles :: [FilePath] -> TcRn ()

Error management

getSrcSpanM :: TcRn SrcSpan

setSrcSpan :: SrcSpan -> TcRn a -> TcRn a

setSrcSpanA :: SrcSpanAnn' ann -> TcRn a -> TcRn a

addLocM :: (a -> TcM b) -> Located a -> TcM b

addLocMA :: (a -> TcM b) -> GenLocated (SrcSpanAnn' ann) a -> TcM b

inGeneratedCode :: TcRn Bool

wrapLocM :: (a -> TcM b) -> Located a -> TcM (Located b)

wrapLocAM :: (a -> TcM b) -> LocatedAn an a -> TcM (Located b)

wrapLocFstM :: (a -> TcM (b, c)) -> Located a -> TcM (Located b, c)

wrapLocFstMA :: (a -> TcM (b, c)) -> GenLocated (SrcSpanAnn' ann) a -> TcM (GenLocated (SrcSpanAnn' ann) b, c)

wrapLocSndM :: (a -> TcM (b, c)) -> Located a -> TcM (b, Located c)

wrapLocSndMA :: (a -> TcM (b, c)) -> GenLocated (SrcSpanAnn' ann) a -> TcM (b, GenLocated (SrcSpanAnn' ann) c)

wrapLocM_ :: (a -> TcM ()) -> Located a -> TcM ()

wrapLocMA_ :: (a -> TcM ()) -> LocatedA a -> TcM ()

wrapLocMA :: (a -> TcM b) -> GenLocated (SrcSpanAnn' ann) a -> TcRn (GenLocated (SrcSpanAnn' ann) b)

getErrsVar :: TcRn (TcRef (Messages TcRnMessage))

setErrsVar :: TcRef (Messages TcRnMessage) -> TcRn a -> TcRn a

addErr :: TcRnMessage -> TcRn ()

failWith :: TcRnMessage -> TcRn a

failAt :: SrcSpan -> TcRnMessage -> TcRn a

addErrAt :: SrcSpan -> TcRnMessage -> TcRn ()

addErrs :: [(SrcSpan, TcRnMessage)] -> TcRn ()

checkErr :: Bool -> TcRnMessage -> TcRn ()

addMessages :: Messages TcRnMessage -> TcRn ()

discardWarnings :: TcRn a -> TcRn a

Usage environment

tcCollectingUsage :: TcM a -> TcM (UsageEnv, a)

tcCollectingUsage thing_inside runs thing_inside and returns the usage information which was collected as part of the execution of thing_inside. Careful: tcCollectingUsage thing_inside itself does not report any usage information, it's up to the caller to incorporate the returned usage information into the larger context appropriately.

tcScalingUsage :: Mult -> TcM a -> TcM a

tcScalingUsage mult thing_inside runs thing_inside and scales all the usage information by mult.

tcEmitBindingUsage :: UsageEnv -> TcM ()

Shared error message stuff: renamer and typechecker

recoverM :: TcRn r -> TcRn r -> TcRn r

mapAndRecoverM :: (a -> TcRn b) -> [a] -> TcRn [b]

Drop elements of the input that fail, so the result list can be shorter than the argument list

mapAndReportM :: (a -> TcRn b) -> [a] -> TcRn [b]

Apply the function to all elements on the input list If all succeed, return the list of results Otherwise fail, propagating all errors

foldAndRecoverM :: (b -> a -> TcRn b) -> b -> [a] -> TcRn b

The accumulator is not updated if the action fails

attemptM :: TcRn r -> TcRn (Maybe r)

tryTc :: TcRn a -> TcRn (Maybe a, Messages TcRnMessage)

askNoErrs :: TcRn a -> TcRn (a, Bool)

discardErrs :: TcRn a -> TcRn a

tryTcDiscardingErrs :: TcM r -> TcM r -> TcM r

checkNoErrs :: TcM r -> TcM r

whenNoErrs :: TcM () -> TcM ()

ifErrsM :: TcRn r -> TcRn r -> TcRn r

failIfErrsM :: TcRn ()

Context management for the type checker

getErrCtxt :: TcM [ErrCtxt]

setErrCtxt :: [ErrCtxt] -> TcM a -> TcM a

addErrCtxt :: SDoc -> TcM a -> TcM a

Add a fixed message to the error context. This message should not do any tidying.

addErrCtxtM :: (TidyEnv -> TcM (TidyEnv, SDoc)) -> TcM a -> TcM a

Add a message to the error context. This message may do tidying.

addLandmarkErrCtxt :: SDoc -> TcM a -> TcM a

Add a fixed landmark message to the error context. A landmark message is always sure to be reported, even if there is a lot of context. It also doesn't count toward the maximum number of contexts reported.

addLandmarkErrCtxtM :: (TidyEnv -> TcM (TidyEnv, SDoc)) -> TcM a -> TcM a

Variant of addLandmarkErrCtxt that allows for monadic operations and tidying.

popErrCtxt :: TcM a -> TcM a

getCtLocM :: CtOrigin -> Maybe TypeOrKind -> TcM CtLoc

setCtLocM :: CtLoc -> TcM a -> TcM a

Diagnostic message generation (type checker)

addErrTc :: TcRnMessage -> TcM ()

addErrTcM :: (TidyEnv, TcRnMessage) -> TcM ()

failWithTc :: TcRnMessage -> TcM a

failWithTcM :: (TidyEnv, TcRnMessage) -> TcM a

checkTc :: Bool -> TcRnMessage -> TcM ()

checkTcM :: Bool -> (TidyEnv, TcRnMessage) -> TcM ()

failIfTc :: Bool -> TcRnMessage -> TcM ()

failIfTcM :: Bool -> (TidyEnv, TcRnMessage) -> TcM ()

mkErrInfo :: TidyEnv -> [ErrCtxt] -> TcM SDoc

addTcRnDiagnostic :: TcRnMessage -> TcM ()

addDetailedDiagnostic :: (ErrInfo -> TcRnMessage) -> TcM ()

A variation of addDiagnostic that takes a function to produce a TcRnDsMessage given some additional context about the diagnostic.

mkTcRnMessage :: SrcSpan -> TcRnMessage -> TcRn (MsgEnvelope TcRnMessage)

reportDiagnostic :: MsgEnvelope TcRnMessage -> TcRn ()

reportDiagnostics :: [MsgEnvelope TcRnMessage] -> TcM ()

warnIf :: Bool -> TcRnMessage -> TcRn ()

Display a warning if a condition is met.

diagnosticTc :: Bool -> TcRnMessage -> TcM ()

Display a warning if a condition is met.

diagnosticTcM :: Bool -> (TidyEnv, TcRnMessage) -> TcM ()

Display a diagnostic if a condition is met.

addDiagnosticTc :: TcRnMessage -> TcM ()

Display a diagnostic in the current context.

addDiagnosticTcM :: (TidyEnv, TcRnMessage) -> TcM ()

Display a diagnostic in a given context.

addDiagnostic :: TcRnMessage -> TcRn ()

Display a diagnostic for the current source location, taken from the TcRn monad.

addDiagnosticAt :: SrcSpan -> TcRnMessage -> TcRn ()

Display a diagnostic for a given source location.

Type constraints

newTcEvBinds :: TcM EvBindsVar

newNoTcEvBinds :: TcM EvBindsVar

Creates an EvBindsVar incapable of holding any bindings. It still tracks covar usages (see comments on ebv_tcvs in GHC.Tc.Types.Evidence), thus must be made monadically

cloneEvBindsVar :: EvBindsVar -> TcM EvBindsVar

addTcEvBind :: EvBindsVar -> EvBind -> TcM ()

addTopEvBinds :: Bag EvBind -> TcM a -> TcM a

getTcEvTyCoVars :: EvBindsVar -> TcM TyCoVarSet

getTcEvBindsMap :: EvBindsVar -> TcM EvBindMap

setTcEvBindsMap :: EvBindsVar -> EvBindMap -> TcM ()

chooseUniqueOccTc :: (OccSet -> OccName) -> TcM OccName

getConstraintVar :: TcM (TcRef WantedConstraints)

setConstraintVar :: TcRef WantedConstraints -> TcM a -> TcM a

emitConstraints :: WantedConstraints -> TcM ()

emitStaticConstraints :: WantedConstraints -> TcM ()

emitSimple :: Ct -> TcM ()

emitSimples :: Cts -> TcM ()

emitImplication :: Implication -> TcM ()

emitImplications :: Bag Implication -> TcM ()

emitInsoluble :: Ct -> TcM ()

emitHole :: Hole -> TcM ()

emitHoles :: Bag Hole -> TcM ()

discardConstraints :: TcM a -> TcM a

Throw out any constraints emitted by the thing_inside

captureConstraints :: TcM a -> TcM (a, WantedConstraints)

tryCaptureConstraints :: TcM a -> TcM (Maybe a, WantedConstraints)

pushLevelAndCaptureConstraints :: TcM a -> TcM (TcLevel, WantedConstraints, a)

The name says it all. The returned TcLevel is the *inner* TcLevel.

pushTcLevelM_ :: TcM a -> TcM a

pushTcLevelM :: TcM a -> TcM (TcLevel, a)

getTcLevel :: TcM TcLevel

setTcLevel :: TcLevel -> TcM a -> TcM a

isTouchableTcM :: TcTyVar -> TcM Bool

getLclTypeEnv :: TcM TcTypeEnv

setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a

traceTcConstraints :: String -> TcM ()

emitNamedTypeHole :: (Name, TcTyVar) -> TcM ()

data IsExtraConstraint

Constructors

YesExtraConstraint

NoExtraConstraint

Instances

Outputable IsExtraConstraint

Defined in GHC.Tc.Utils.Monad

Methods

ppr :: IsExtraConstraint -> SDoc

emitAnonTypeHole :: IsExtraConstraint -> TcTyVar -> TcM ()

Template Haskell context

recordThUse :: TcM ()

recordThSpliceUse :: TcM ()

recordThNeededRuntimeDeps :: [Linkable] -> PkgsLoaded -> TcM ()

keepAlive :: Name -> TcRn ()

getStage :: TcM ThStage

getStageAndBindLevel :: Name -> TcRn (Maybe (TopLevelFlag, ThLevel, ThStage))

setStage :: ThStage -> TcM a -> TcRn a

addModFinalizersWithLclEnv :: ThModFinalizers -> TcM ()

Adds the given modFinalizers to the global environment and set them to use the current local environment.

Safe Haskell context

recordUnsafeInfer :: Messages TcRnMessage -> TcM ()

Mark that safe inference has failed See Note [Safe Haskell Overlapping Instances Implementation] although this is used for more than just that failure case.

finalSafeMode :: DynFlags -> TcGblEnv -> IO SafeHaskellMode

Figure out the final correct safe haskell mode

fixSafeInstances :: SafeHaskellMode -> [ClsInst] -> [ClsInst]

Switch instances to safe instances if we're in Safe mode.

Stuff for the renamer's local env

getLocalRdrEnv :: RnM LocalRdrEnv

setLocalRdrEnv :: LocalRdrEnv -> RnM a -> RnM a

Stuff for interface decls

mkIfLclEnv :: Module -> SDoc -> IsBootInterface -> IfLclEnv

initIfaceTcRn :: IfG a -> TcRn a

Run an IfG (top-level interface monad) computation inside an existing TcRn (typecheck-renaming monad) computation by initializing an IfGblEnv based on TcGblEnv.

initIfaceCheck :: SDoc -> HscEnv -> IfG a -> IO a

initIfaceLcl :: Module -> SDoc -> IsBootInterface -> IfL a -> IfM lcl a

initIfaceLclWithSubst :: Module -> SDoc -> IsBootInterface -> NameShape -> IfL a -> IfM lcl a

Initialize interface typechecking, but with a NameShape to apply when typechecking top-level OccNames (see lookupIfaceTop)

initIfaceLoad :: HscEnv -> IfG a -> IO a

initIfaceLoad can be used when there's no chance that the action will call typecheckIface when inside a module loop and hence tcIfaceGlobal.

initIfaceLoadModule :: HscEnv -> Module -> IfG a -> IO a

This is used when we are doing to call typecheckModule on an ModIface, if it's part of a loop with some other modules then we need to use their IORef TypeEnv vars when typechecking but crucially not our own.

getIfModule :: IfL Module

failIfM :: SDoc -> IfL a

forkM :: SDoc -> IfL a -> IfL a

Run thing_inside in an interleaved thread. It shares everything with the parent thread, so this is DANGEROUS.

It throws an error if the computation fails

It's used for lazily type-checking interface signatures, which is pretty benign.

See Note [Masking exceptions in forkM]

setImplicitEnvM :: TypeEnv -> IfL a -> IfL a

withException :: MonadIO m => SDocContext -> m (MaybeErr SDoc a) -> m a

A convenient wrapper for taking a MaybeErr SDoc a and throwing an exception if it is an error.

Stuff for cost centres.

getCCIndexM :: (gbl -> TcRef CostCentreState) -> FastString -> TcRnIf gbl lcl CostCentreIndex

Get the next cost centre index associated with a given name.

getCCIndexTcM :: FastString -> TcM CostCentreIndex

See getCCIndexM.

Types etc.

module GHC.Tc.Types

module GHC.Data.IOEnv

Orphan instances

MonadUnique (IOEnv (Env gbl lcl))

Methods

getUniqueSupplyM :: IOEnv (Env gbl lcl) UniqSupply

getUniqueM :: IOEnv (Env gbl lcl) Unique

getUniquesM :: IOEnv (Env gbl lcl) [Unique]