Skip to content

HORIZON HASKELL Docs lts/ghc-10.0.xfc4e5982026-10-11Search names, modules, packages, or :: a typeCtrl K

GHC 10.0.0.20260917 · lts/ghc-10.0.x · fc4e598 · 2026-10-11

Moduleghc-10.0.0.20260917GHC2024

GHC.Tc.Types.CtLoc

5 types
36 values

Packageghc-10.0.0.20260917
Exports41
LanguageGHC2024
LicenceBSD-3-Clause
SourceCtLoc.hs

CtLoc

20 declarations

datadata CtLoc

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
- 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

valuectLocSpan :: CtLoc -> RealSrcSpan

valuectLocEnv :: CtLoc -> CtLocEnv

valuectLocLevel :: CtLoc -> TcLevel

valuectLocOrigin :: CtLoc -> CtOrigin

valuectLocTypeOrKind_maybe :: CtLoc -> Maybe TypeOrKind

valuetoInvisibleLoc :: InvisibleBit -> CtLoc -> CtLoc

valuectLocDepth :: CtLoc -> SubGoalDepth

valuebumpCtLocDepth :: CtLoc -> CtLoc

valueresetCtLocDepth :: CtLoc -> CtLoc

valueisGivenLoc :: CtLoc -> Bool

valuemkGivenLoc :: TcLevel -> SkolemInfoAnon -> CtLocEnv -> CtLoc

valuemkKindEqLoc :: TcType -> TcType -> CtLoc -> CtLoc

valuesetCtLocOrigin :: CtLoc -> CtOrigin -> CtLoc

valueupdateCtLocOrigin :: CtLoc -> (CtOrigin -> CtOrigin) -> CtLoc

valuesetCtLocEnv :: CtLoc -> CtLocEnv -> CtLoc

valuesetCtLocSpan :: CtLoc -> RealSrcSpan -> CtLoc

valuepprCtLoc :: CtLoc -> SDoc

valueadjustCtLoc

valueadjustCtLocTyConBinder

CtLocEnv

7 declarations

datadata CtLocEnv

Local typechecker environment for a constraint.

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

See also TcLclCtxt.

Constructors

CtLocEnv
- ctl_ctxt :: !ErrCtxtStack
- ctl_loc :: !RealSrcSpan
- ctl_bndrs :: !TcBinderStack
- ctl_tclvl :: !TcLevel
- ctl_in_gen_code :: !Bool
- ctl_rdr :: !LocalRdrEnv

valuegetCtLocEnvLoc :: CtLocEnv -> RealSrcSpan

valuesetCtLocEnvLoc :: CtLocEnv -> SrcSpan -> CtLocEnv

valuesetCtLocRealLoc :: CtLocEnv -> RealSrcSpan -> CtLocEnv

valuegetCtLocEnvLvl :: CtLocEnv -> TcLevel

valuesetCtLocEnvLvl :: CtLocEnv -> TcLevel -> CtLocEnv

valuectLocEnvInGeneratedCode :: CtLocEnv -> Bool

SubGoalDepth

5 declarations

newtypenewtype SubGoalDepth

See Note [SubGoalDepth]

Instances3Eq, Ord, Outputable

Eq SubGoalDepthDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc
Ord SubGoalDepthDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc
Outputable SubGoalDepthDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc

valueinitialSubGoalDepth :: SubGoalDepth

valuemaxSubGoalDepth :: SubGoalDepth -> SubGoalDepth -> SubGoalDepth

valuebumpSubGoalDepth :: SubGoalDepth -> SubGoalDepth

valuesubGoalDepthExceeded :: IntWithInf -> SubGoalDepth -> Bool

Explanations

6 declarations

datadata CtExplanations

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
- 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.

Instances3Semigroup, Monoid, Outputable

Semigroup CtExplanationsDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc
Monoid CtExplanationsDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc
Outputable CtExplanationsDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc

valuectLocExplanations :: CtLoc -> CtExplanations

valueupdCtLocExplanations :: (CtExplanations -> CtExplanations) -> CtLoc -> CtLoc

valueoutOfScopeNT :: DataCon -> CtExplanations

valuestuckDataFamApp :: TyCon -> [Type] -> CtExplanations

valuenullCtExplanations :: CtExplanations -> Bool

RoleExplanation

3 declarations

datadata RoleExplanation

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

Constructors

TyConArg TyCon Int Role
The TyCon has the given role this argument.
NominalAppTy Type
The role of the argument in an AppTy is nominal.
Store the function type in the AppTy.

Instances1Outputable

Outputable RoleExplanationDefined in ghc-10.0.0.20260917 · GHC.Tc.Types.CtLoc

valuetyConAppRoleExplanation

:: Role
-> TyCon
-> (Int, Role)
-> Maybe RoleExplanation

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).

valueappTyRoleExplanation :: Type -> CtOrigin -> Maybe RoleExplanation