Safe Haskell	None
Language	GHC2024

GHC.Tc.Types.CtLoc

Contents

CtLoc
CtLocEnv
SubGoalDepth
Explanations
RoleExplanation

Synopsis

data CtLoc = CtLoc {
- ctl_origin :: CtOrigin
- ctl_env :: CtLocEnv
- ctl_t_or_k :: Maybe TypeOrKind
- ctl_expln :: CtExplanations
- ctl_depth :: !SubGoalDepth
}
ctLocSpan :: CtLoc -> RealSrcSpan
ctLocEnv :: CtLoc -> CtLocEnv
ctLocLevel :: CtLoc -> TcLevel
ctLocOrigin :: CtLoc -> CtOrigin
ctLocTypeOrKind_maybe :: CtLoc -> Maybe TypeOrKind
toInvisibleLoc :: InvisibleBit -> CtLoc -> CtLoc
ctLocDepth :: CtLoc -> SubGoalDepth
bumpCtLocDepth :: CtLoc -> CtLoc
resetCtLocDepth :: CtLoc -> CtLoc
isGivenLoc :: CtLoc -> Bool
mkGivenLoc :: TcLevel -> SkolemInfoAnon -> CtLocEnv -> CtLoc
mkKindEqLoc :: TcType -> TcType -> CtLoc -> CtLoc
setCtLocOrigin :: CtLoc -> CtOrigin -> CtLoc
updateCtLocOrigin :: CtLoc -> (CtOrigin -> CtOrigin) -> CtLoc
setCtLocEnv :: CtLoc -> CtLocEnv -> CtLoc
setCtLocSpan :: CtLoc -> RealSrcSpan -> CtLoc
pprCtLoc :: CtLoc -> SDoc
adjustCtLoc :: Maybe InvisibleBit -> Bool -> Maybe RoleExplanation -> CtLoc -> CtLoc
adjustCtLocTyConBinder :: Maybe TyConBinder -> Maybe RoleExplanation -> CtLoc -> CtLoc
data CtLocEnv = CtLocEnv {
- ctl_ctxt :: ![ErrCtxt]
- ctl_loc :: !RealSrcSpan
- ctl_bndrs :: !TcBinderStack
- ctl_tclvl :: !TcLevel
- ctl_in_gen_code :: !Bool
- ctl_rdr :: !LocalRdrEnv
}
getCtLocEnvLoc :: CtLocEnv -> RealSrcSpan
setCtLocEnvLoc :: CtLocEnv -> SrcSpan -> CtLocEnv
setCtLocRealLoc :: CtLocEnv -> RealSrcSpan -> CtLocEnv
getCtLocEnvLvl :: CtLocEnv -> TcLevel
setCtLocEnvLvl :: CtLocEnv -> TcLevel -> CtLocEnv
ctLocEnvInGeneratedCode :: CtLocEnv -> Bool
data SubGoalDepth
initialSubGoalDepth :: SubGoalDepth
maxSubGoalDepth :: SubGoalDepth -> SubGoalDepth -> SubGoalDepth
bumpSubGoalDepth :: SubGoalDepth -> SubGoalDepth
subGoalDepthExceeded :: IntWithInf -> SubGoalDepth -> Bool
data CtExplanations = CtExplanations {
- ctexpl_roleExplanations :: [RoleExplanation]
- ctexpl_outOfScopeNTs :: UniqSet DataCon
- ctexpl_stuckDataFamApps :: UniqMap TyCon (NonEmpty [Type])
}
ctLocExplanations :: CtLoc -> CtExplanations
updCtLocExplanations :: (CtExplanations -> CtExplanations) -> CtLoc -> CtLoc
outOfScopeNT :: DataCon -> CtExplanations
stuckDataFamApp :: TyCon -> [Type] -> CtExplanations
nullCtExplanations :: CtExplanations -> Bool
data RoleExplanation
- = TyConArg TyCon Int Role
- | NominalAppTy Type
tyConAppRoleExplanation :: Role -> TyCon -> (Int, Role) -> Maybe RoleExplanation
appTyRoleExplanation :: Type -> CtOrigin -> Maybe RoleExplanation

CtLoc

data CtLoc Source #

CtLoc gives information about where a constraint came from.

This is important for decent error message reporting, because dictionaries don't appear in the original source code.

See Note [CtLoc].

Constructors

CtLoc
Fields ctl_origin :: CtOrigin ctl_env :: CtLocEnv ctl_t_or_k :: Maybe TypeOrKind ctl_expln :: CtExplanations Explanations we can display to the user if the constraint goes unsolved; see Note [CtExplanations] ctl_depth :: !SubGoalDepth

ctLocSpan :: CtLoc -> RealSrcSpan Source #

ctLocEnv :: CtLoc -> CtLocEnv Source #

ctLocLevel :: CtLoc -> TcLevel Source #

ctLocOrigin :: CtLoc -> CtOrigin Source #

ctLocTypeOrKind_maybe :: CtLoc -> Maybe TypeOrKind Source #

toInvisibleLoc :: InvisibleBit -> CtLoc -> CtLoc Source #

ctLocDepth :: CtLoc -> SubGoalDepth Source #

bumpCtLocDepth :: CtLoc -> CtLoc Source #

resetCtLocDepth :: CtLoc -> CtLoc Source #

isGivenLoc :: CtLoc -> Bool Source #

mkGivenLoc :: TcLevel -> SkolemInfoAnon -> CtLocEnv -> CtLoc Source #

mkKindEqLoc :: TcType -> TcType -> CtLoc -> CtLoc Source #

setCtLocOrigin :: CtLoc -> CtOrigin -> CtLoc Source #

updateCtLocOrigin :: CtLoc -> (CtOrigin -> CtOrigin) -> CtLoc Source #

setCtLocEnv :: CtLoc -> CtLocEnv -> CtLoc Source #

setCtLocSpan :: CtLoc -> RealSrcSpan -> CtLoc Source #

pprCtLoc :: CtLoc -> SDoc Source #

adjustCtLoc :: Maybe InvisibleBit -> Bool -> Maybe RoleExplanation -> CtLoc -> CtLoc Source #

adjustCtLocTyConBinder :: Maybe TyConBinder -> Maybe RoleExplanation -> CtLoc -> CtLoc Source #

CtLocEnv

data CtLocEnv Source #

Local typechecker environment for a constraint.

Used to restore the environment of a constraint when reporting errors, see setCtLocM.

SubGoalDepth

data SubGoalDepth Source #

See Note [SubGoalDepth]

Instances

Instances details

Outputable SubGoalDepth Source #
Instance details Defined in GHC.Tc.Types.CtLoc Methods ppr :: SubGoalDepth -> SDoc Source #
Eq SubGoalDepth Source #
Instance details Defined in GHC.Tc.Types.CtLoc Methods (==) :: SubGoalDepth -> SubGoalDepth -> Bool Source # (/=) :: SubGoalDepth -> SubGoalDepth -> Bool Source #
Ord SubGoalDepth Source #
Instance details Defined in GHC.Tc.Types.CtLoc Methods compare :: SubGoalDepth -> SubGoalDepth -> Ordering Source # (<) :: SubGoalDepth -> SubGoalDepth -> Bool Source # (<=) :: SubGoalDepth -> SubGoalDepth -> Bool Source # (>) :: SubGoalDepth -> SubGoalDepth -> Bool Source # (>=) :: SubGoalDepth -> SubGoalDepth -> Bool Source # max :: SubGoalDepth -> SubGoalDepth -> SubGoalDepth Source # min :: SubGoalDepth -> SubGoalDepth -> SubGoalDepth Source #

initialSubGoalDepth :: SubGoalDepth Source #

maxSubGoalDepth :: SubGoalDepth -> SubGoalDepth -> SubGoalDepth Source #

bumpSubGoalDepth :: SubGoalDepth -> SubGoalDepth Source #

subGoalDepthExceeded :: IntWithInf -> SubGoalDepth -> Bool Source #

Explanations

data CtExplanations Source #

Explanations that can be presented to the user about why the solver might have failed to solve a constraint. See Note [CtExplanations].

For example: couldn't solve a representational equality because a newtype constructor was out of scope.

Constructors

CtExplanations

Fields

ctexpl_roleExplanations :: [RoleExplanation]
Explanations to the user that involve roles, e.g. remarking that a TyCon has nominal role in one of its arguments.
ctexpl_outOfScopeNTs :: UniqSet DataCon
Newtypes that could not be unwrapped because their constructors were not in scope.
NB: store the DataCon rather than the TyCon, as this avoids any issues with internal representation TyCons for data families, as in 'data family D a; newtype instance D Int = MkDInt Bool'.
ctexpl_stuckDataFamApps :: UniqMap TyCon (NonEmpty [Type])
Data family applications that could not be reduced.

Instances

Instances details

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

ctLocExplanations :: CtLoc -> CtExplanations Source #

updCtLocExplanations :: (CtExplanations -> CtExplanations) -> CtLoc -> CtLoc Source #

outOfScopeNT :: DataCon -> CtExplanations Source #

stuckDataFamApp :: TyCon -> [Type] -> CtExplanations Source #

nullCtExplanations :: CtExplanations -> Bool Source #

RoleExplanation

data RoleExplanation Source #

Information about why a representational equality gave rise to a nominal equality.

Constructors

TyConArg

The TyCon has the given role this argument.

Fields

TyCon
Int
argument position (starting from 1); may be greater than the arity of the TyCon in the case of an over-saturated application
Role

NominalAppTy Type

The role of the argument in an AppTy is nominal.

Store the function type in the AppTy.

Instances

Instances details

Outputable RoleExplanation Source #
Instance details Defined in GHC.Tc.Types.CtLoc Methods ppr :: RoleExplanation -> SDoc Source #

tyConAppRoleExplanation :: Role -> TyCon -> (Int, Role) -> Maybe RoleExplanation Source #

Add a role explanation when decomposing 'T a ~r1 T b' for some role r1 into 'a ~r2 b' with stronger role r2 (e.g. turning a representational equality into a nominal equality).

appTyRoleExplanation :: Type -> CtOrigin -> Maybe RoleExplanation Source #

CtLocEnv
Fields ctl_ctxt :: ![ErrCtxt] ctl_loc :: !RealSrcSpan ctl_bndrs :: !TcBinderStack ctl_tclvl :: !TcLevel ctl_in_gen_code :: !Bool ctl_rdr :: !LocalRdrEnv