{-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE GADTs #-} {-# LANGUAGE KindSignatures #-} module GHC.Tc.Errors.Types ( -- * Main types TcRnMessage(..) , mkTcRnUnknownMessage , TcRnMessageDetailed(..) , TypeDataForbids(..) , ErrInfo(..) , FixedRuntimeRepProvenance(..) , pprFixedRuntimeRepProvenance , ShadowedNameProvenance(..) , RecordFieldPart(..) , IllegalNewtypeReason(..) , InjectivityErrReason(..) , HasKinds(..) , hasKinds , SuggestUndecidableInstances(..) , suggestUndecidableInstances , SuggestUnliftedTypes(..) , DataSort(..), ppDataSort , AllowedDataResKind(..) , NotClosedReason(..) , SuggestPartialTypeSignatures(..) , suggestPartialTypeSignatures , DeriveInstanceErrReason(..) , UsingGeneralizedNewtypeDeriving(..) , usingGeneralizedNewtypeDeriving , DeriveAnyClassEnabled(..) , deriveAnyClassEnabled , DeriveInstanceBadConstructor(..) , HasWildcard(..) , hasWildcard , BadAnonWildcardContext(..) , SoleExtraConstraintWildcardAllowed(..) , DeriveGenericsErrReason(..) , HasAssociatedDataFamInsts(..) , hasAssociatedDataFamInsts , AssociatedTyLastVarInKind(..) , associatedTyLastVarInKind , AssociatedTyNotParamOverLastTyVar(..) , associatedTyNotParamOverLastTyVar , MissingSignature(..) , Exported(..) , HsDocContext(..) , FixedRuntimeRepErrorInfo(..) , ErrorItem(..), errorItemOrigin, errorItemEqRel, errorItemPred, errorItemCtLoc , SolverReport(..), SolverReportSupplementary(..) , SolverReportWithCtxt(..) , SolverReportErrCtxt(..) , getUserGivens, discardProvCtxtGivens , TcSolverReportMsg(..) , CannotUnifyVariableReason(..) , MismatchMsg(..) , MismatchEA(..) , mkPlainMismatchMsg, mkBasicMismatchMsg , WhenMatching(..) , ExpectedActualInfo(..) , TyVarInfo(..), SameOccInfo(..) , AmbiguityInfo(..) , CND_Extra(..) , FitsMbSuppressed(..) , ValidHoleFits(..), noValidHoleFits , HoleFitDispConfig(..) , RelevantBindings(..), pprRelevantBindings , PromotionErr(..), pprPECategory, peCategory , NotInScopeError(..), mkTcRnNotInScope , ImportError(..) , HoleError(..) , CoercibleMsg(..) , PotentialInstances(..) , UnsupportedCallConvention(..) , ExpectedBackends , ArgOrResult(..) , MatchArgsContext(..), MatchArgBadMatches(..) , ConversionFailReason(..) , UnrepresentableTypeDescr(..) , LookupTHInstNameErrReason(..) , SplicePhase(..) , THDeclDescriptor(..) , RunSpliceFailReason(..) , ThingBeingConverted(..) , IllegalDecls(..) , EmptyStatementGroupErrReason(..) , UnexpectedStatement(..) ) where import GHC.Prelude import GHC.Hs import {-# SOURCE #-} GHC.Tc.Types (TcIdSigInfo, TcTyThing) import {-# SOURCE #-} GHC.Tc.Errors.Hole.FitTypes (HoleFit) import GHC.Tc.Types.Constraint import GHC.Tc.Types.Evidence (EvBindsVar) import GHC.Tc.Types.Origin ( CtOrigin (ProvCtxtOrigin), SkolemInfoAnon (SigSkol) , UserTypeCtxt (PatSynCtxt), TyVarBndrs, TypedThing , FixedRuntimeRepOrigin(..) ) import GHC.Tc.Types.Rank (Rank) import GHC.Tc.Utils.TcType (IllegalForeignTypeReason, TcType) import GHC.Types.Error import GHC.Types.Hint (UntickedPromotedThing(..)) import GHC.Types.ForeignCall (CLabelString) import GHC.Types.Name (Name, OccName, getSrcLoc, getSrcSpan) import qualified GHC.Types.Name.Occurrence as OccName import GHC.Types.Name.Reader import GHC.Types.SrcLoc import GHC.Types.TyThing (TyThing) import GHC.Types.Var (Id, TyCoVar, TyVar, TcTyVar) import GHC.Types.Var.Env (TidyEnv) import GHC.Types.Var.Set (TyVarSet, VarSet) import GHC.Unit.Types (Module) import GHC.Utils.Outputable import GHC.Core.Class (Class, ClassMinimalDef) import GHC.Core.Coercion.Axiom (CoAxBranch) import GHC.Core.ConLike (ConLike) import GHC.Core.DataCon (DataCon) import GHC.Core.FamInstEnv (FamInst) import GHC.Core.InstEnv (ClsInst) import GHC.Core.PatSyn (PatSyn) import GHC.Core.Predicate (EqRel, predTypeEqRel) import GHC.Core.TyCon (TyCon, TyConFlavour) import GHC.Core.Type (Kind, Type, ThetaType, PredType) import GHC.Driver.Backend (Backend) import GHC.Unit.State (UnitState) import GHC.Types.Basic import GHC.Utils.Misc (capitalise, filterOut) import qualified GHC.LanguageExtensions as LangExt import GHC.Data.FastString (FastString) import GHC.Exception.Type (SomeException) import Language.Haskell.Syntax.Basic (FieldLabelString(..)) import qualified Data.List.NonEmpty as NE import Data.Typeable (Typeable) import GHC.Unit.Module.Warnings (WarningTxt) import qualified Language.Haskell.TH.Syntax as TH import GHC.Generics ( Generic ) {- Note [Migrating TcM Messages] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ As part of #18516, we are slowly migrating the diagnostic messages emitted and reported in the TcM from SDoc to TcRnMessage. Historically, GHC emitted some diagnostics in 3 pieces, i.e. there were lots of error-reporting functions that accepted 3 SDocs an input: one for the important part of the message, one for the context and one for any supplementary information. Consider the following: • Couldn't match expected type ‘Int’ with actual type ‘Char’ • In the expression: x4 In a stmt of a 'do' block: return (x2, x4) In the expression: Under the hood, the reporting functions in Tc.Utils.Monad were emitting "Couldn't match" as the important part, "In the expression" as the context and "In a stmt..In the expression" as the supplementary, with the context and supplementary usually smashed together so that the final message would be composed only by two SDoc (which would then be bulleted like in the example). In order for us to smooth out the migration to the new diagnostic infrastructure, we introduce the 'ErrInfo' and 'TcRnMessageDetailed' types, which serve exactly the purpose of bridging the two worlds together without breaking the external API or the existing format of messages reported by GHC. Using 'ErrInfo' and 'TcRnMessageDetailed' also allows us to move away from the SDoc-ridden diagnostic API inside Tc.Utils.Monad, enabling further refactorings. In the future, once the conversion will be complete and we will successfully eradicate any use of SDoc in the diagnostic reporting of GHC, we can surely revisit the usage and existence of these two types, which for now remain a "necessary evil". -} -- The majority of TcRn messages come with extra context about the error, -- and this newtype captures it. See Note [Migrating TcM Messages]. data ErrInfo = ErrInfo { ErrInfo -> SDoc errInfoContext :: !SDoc -- ^ Extra context associated to the error. , ErrInfo -> SDoc errInfoSupplementary :: !SDoc -- ^ Extra supplementary info associated to the error. } -- | 'TcRnMessageDetailed' is an \"internal\" type (used only inside -- 'GHC.Tc.Utils.Monad' that wraps a 'TcRnMessage' while also providing -- any extra info needed to correctly pretty-print this diagnostic later on. data TcRnMessageDetailed = TcRnMessageDetailed !ErrInfo -- ^ Extra info associated with the message !TcRnMessage deriving (forall x. TcRnMessageDetailed -> Rep TcRnMessageDetailed x) -> (forall x. Rep TcRnMessageDetailed x -> TcRnMessageDetailed) -> Generic TcRnMessageDetailed forall x. Rep TcRnMessageDetailed x -> TcRnMessageDetailed forall x. TcRnMessageDetailed -> Rep TcRnMessageDetailed x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. TcRnMessageDetailed -> Rep TcRnMessageDetailed x from :: forall x. TcRnMessageDetailed -> Rep TcRnMessageDetailed x $cto :: forall x. Rep TcRnMessageDetailed x -> TcRnMessageDetailed to :: forall x. Rep TcRnMessageDetailed x -> TcRnMessageDetailed Generic mkTcRnUnknownMessage :: (Diagnostic a, Typeable a, DiagnosticOpts a ~ NoDiagnosticOpts) => a -> TcRnMessage mkTcRnUnknownMessage :: forall a. (Diagnostic a, Typeable a, DiagnosticOpts a ~ NoDiagnosticOpts) => a -> TcRnMessage mkTcRnUnknownMessage a diag = UnknownDiagnostic -> TcRnMessage TcRnUnknownMessage (a -> UnknownDiagnostic forall a. (DiagnosticOpts a ~ NoDiagnosticOpts, Diagnostic a, Typeable a) => a -> UnknownDiagnostic UnknownDiagnostic a diag) -- | An error which might arise during typechecking/renaming. data TcRnMessage where {-| Simply wraps an unknown 'Diagnostic' message @a@. It can be used by plugins to provide custom diagnostic messages originated during typechecking/renaming. -} TcRnUnknownMessage :: UnknownDiagnostic -> TcRnMessage {-| TcRnMessageWithInfo is a constructor which is used when extra information is needed to be provided in order to qualify a diagnostic and where it was originated (and why). It carries an extra 'UnitState' which can be used to pretty-print some names and it wraps a 'TcRnMessageDetailed', which includes any extra context associated with this diagnostic. -} TcRnMessageWithInfo :: !UnitState -- ^ The 'UnitState' will allow us to pretty-print -- some diagnostics with more detail. -> !TcRnMessageDetailed -> TcRnMessage {-| TcRnWithHsDocContext annotates an error message with the context in which it originated. -} TcRnWithHsDocContext :: !HsDocContext -> !TcRnMessage -> TcRnMessage {-| TcRnSolverReport is the constructor used to report unsolved constraints after constraint solving, as well as other errors such as hole fit errors. See the documentation of the 'TcSolverReportMsg' datatype for an overview of the different errors. -} TcRnSolverReport :: SolverReportWithCtxt -> DiagnosticReason -> [GhcHint] -> TcRnMessage -- TODO: split up TcRnSolverReport into several components, -- so that we can compute the reason and hints, as opposed -- to having to pass them here. {-| TcRnRedundantConstraints is a warning that is emitted when a binding has a user-written type signature which contains superfluous constraints. Example: f :: (Eq a, Ord a) => a -> a -> a f x y = (x < y) || x == y -- `Eq a` is superfluous: the `Ord a` constraint suffices. Test cases: T9939, T10632, T18036a, T20602, PluralS, T19296. -} TcRnRedundantConstraints :: [Id] -> (SkolemInfoAnon, Bool) -- ^ The contextual skolem info. -- The boolean controls whether we -- want to show it in the user message. -- (Nice to keep track of the info in either case, -- for other users of the GHC API.) -> TcRnMessage {-| TcRnInaccessibleCode is a warning that is emitted when the RHS of a pattern match is inaccessible, because the constraint solver has detected a contradiction. Example: data B a where { MkTrue :: B True; MkFalse :: B False } foo :: B False -> Bool foo MkFalse = False foo MkTrue = True -- Inaccessible: requires True ~ False Test cases: T7293, T7294, T15558, T17646, T18572, T18610, tcfail167. -} TcRnInaccessibleCode :: Implication -- ^ The implication containing a contradiction. -> SolverReportWithCtxt -- ^ The contradiction. -> TcRnMessage {-| A type which was expected to have a fixed runtime representation does not have a fixed runtime representation. Example: data D (a :: TYPE r) = MkD a Test cases: T11724, T18534, RepPolyPatSynArg, RepPolyPatSynUnliftedNewtype, RepPolyPatSynRes, T20423 -} TcRnTypeDoesNotHaveFixedRuntimeRep :: !Type -> !FixedRuntimeRepProvenance -> !ErrInfo -- Extra info accumulated in the TcM monad -> TcRnMessage {-| TcRnImplicitLift is a warning (controlled with -Wimplicit-lift) that occurs when a Template Haskell quote implicitly uses 'lift'. Example: warning1 :: Lift t => t -> Q Exp warning1 x = [| x |] Test cases: th/T17804 -} TcRnImplicitLift :: Name -> !ErrInfo -> TcRnMessage {-| TcRnUnusedPatternBinds is a warning (controlled with -Wunused-pattern-binds) that occurs if a pattern binding binds no variables at all, unless it is a lone wild-card pattern, or a banged pattern. Example: Just _ = rhs3 -- Warning: unused pattern binding (_, _) = rhs4 -- Warning: unused pattern binding _ = rhs3 -- No warning: lone wild-card pattern !() = rhs4 -- No warning: banged pattern; behaves like seq Test cases: rename/{T13646,T17c,T17e,T7085} -} TcRnUnusedPatternBinds :: HsBind GhcRn -> TcRnMessage {-| TcRnDodgyImports is a warning (controlled with -Wdodgy-imports) that occurs when a datatype 'T' is imported with all constructors, i.e. 'T(..)', but has been exported abstractly, i.e. 'T'. Test cases: rename/should_compile/T7167 -} TcRnDodgyImports :: RdrName -> TcRnMessage {-| TcRnDodgyExports is a warning (controlled by -Wdodgy-exports) that occurs when a datatype 'T' is exported with all constructors, i.e. 'T(..)', but is it just a type synonym or a type/data family. Example: module Foo ( T(..) -- Warning: T is a type synonym , A(..) -- Warning: A is a type family , C(..) -- Warning: C is a data family ) where type T = Int type family A :: * -> * data family C :: * -> * Test cases: warnings/should_compile/DodgyExports01 -} TcRnDodgyExports :: Name -> TcRnMessage {-| TcRnMissingImportList is a warning (controlled by -Wmissing-import-lists) that occurs when an import declaration does not explicitly list all the names brought into scope. Test cases: rename/should_compile/T4489 -} TcRnMissingImportList :: IE GhcPs -> TcRnMessage {-| When a module marked trustworthy or unsafe (using -XTrustworthy or -XUnsafe) is compiled with a plugin, the TcRnUnsafeDueToPlugin warning (controlled by -Wunsafe) is used as the reason the module was inferred to be unsafe. This warning is not raised if the -fplugin-trustworthy flag is passed. Test cases: plugins/T19926 -} TcRnUnsafeDueToPlugin :: TcRnMessage {-| TcRnModMissingRealSrcSpan is an error that occurs when compiling a module that lacks an associated 'RealSrcSpan'. Test cases: None -} TcRnModMissingRealSrcSpan :: Module -> TcRnMessage {-| TcRnIdNotExportedFromModuleSig is an error pertaining to backpack that occurs when an identifier required by a signature is not exported by the module or signature that is being used as a substitution for that signature. Example(s): None Test cases: backpack/should_fail/bkpfail36 -} TcRnIdNotExportedFromModuleSig :: Name -> Module -> TcRnMessage {-| TcRnIdNotExportedFromLocalSig is an error pertaining to backpack that occurs when an identifier which is necessary for implementing a module signature is not exported from that signature. Example(s): None Test cases: backpack/should_fail/bkpfail30 backpack/should_fail/bkpfail31 backpack/should_fail/bkpfail34 -} TcRnIdNotExportedFromLocalSig :: Name -> TcRnMessage {-| TcRnShadowedName is a warning (controlled by -Wname-shadowing) that occurs whenever an inner-scope value has the same name as an outer-scope value, i.e. the inner value shadows the outer one. This can catch typographical errors that turn into hard-to-find bugs. The warning is suppressed for names beginning with an underscore. Examples(s): f = ... let f = id in ... f ... -- NOT OK, 'f' is shadowed f x = do { _ignore <- this; _ignore <- that; return (the other) } -- suppressed via underscore Test cases: typecheck/should_compile/T10971a rename/should_compile/rn039 rename/should_compile/rn064 rename/should_compile/T1972 rename/should_fail/T2723 rename/should_compile/T3262 driver/werror -} TcRnShadowedName :: OccName -> ShadowedNameProvenance -> TcRnMessage {-| TcRnDuplicateWarningDecls is an error that occurs whenever a warning is declared twice. Examples(s): None. Test cases: None. -} TcRnDuplicateWarningDecls :: !(LocatedN RdrName) -> !RdrName -> TcRnMessage {-| TcRnDuplicateWarningDecls is an error that occurs whenever the constraint solver in the simplifier hits the iterations' limit. Examples(s): None. Test cases: None. -} TcRnSimplifierTooManyIterations :: Cts -> !IntWithInf -- ^ The limit. -> WantedConstraints -> TcRnMessage {-| TcRnIllegalPatSynDecl is an error that occurs whenever there is an illegal pattern synonym declaration. Examples(s): varWithLocalPatSyn x = case x of P -> () where pattern P = () -- not valid, it can't be local, it must be defined at top-level. Test cases: patsyn/should_fail/local -} TcRnIllegalPatSynDecl :: !(LIdP GhcPs) -> TcRnMessage {-| TcRnLinearPatSyn is an error that occurs whenever a pattern synonym signature uses a field that is not unrestricted. Example(s): None Test cases: linear/should_fail/LinearPatSyn2 -} TcRnLinearPatSyn :: !Type -> TcRnMessage {-| TcRnEmptyRecordUpdate is an error that occurs whenever a record is updated without specifying any field. Examples(s): $(deriveJSON defaultOptions{} ''Bad) -- not ok, no fields selected for update of defaultOptions Test cases: th/T12788 -} TcRnEmptyRecordUpdate :: TcRnMessage {-| TcRnIllegalFieldPunning is an error that occurs whenever field punning is used without the 'NamedFieldPuns' extension enabled. Examples(s): data Foo = Foo { a :: Int } foo :: Foo -> Int foo Foo{a} = a -- Not ok, punning used without extension. Test cases: parser/should_fail/RecordDotSyntaxFail12 -} TcRnIllegalFieldPunning :: !(Located RdrName) -> TcRnMessage {-| TcRnIllegalWildcardsInRecord is an error that occurs whenever wildcards (..) are used in a record without the relevant extension being enabled. Examples(s): data Foo = Foo { a :: Int } foo :: Foo -> Int foo Foo{..} = a -- Not ok, wildcards used without extension. Test cases: parser/should_fail/RecordWildCardsFail -} TcRnIllegalWildcardsInRecord :: !RecordFieldPart -> TcRnMessage {-| TcRnIllegalWildcardInType is an error that occurs when a wildcard appears in a type in a location in which wildcards aren't allowed. Examples: Type synonyms: type T = _ Class declarations and instances: class C _ instance C _ Standalone kind signatures: type D :: _ data D Test cases: ExtraConstraintsWildcardInTypeSplice2 ExtraConstraintsWildcardInTypeSpliceUsed ExtraConstraintsWildcardNotLast ExtraConstraintsWildcardTwice NestedExtraConstraintsWildcard NestedNamedExtraConstraintsWildcard PartialClassMethodSignature PartialClassMethodSignature2 T12039 T13324_fail1 UnnamedConstraintWildcard1 UnnamedConstraintWildcard2 WildcardInADT1 WildcardInADT2 WildcardInADT3 WildcardInADTContext1 WildcardInDefault WildcardInDefaultSignature WildcardInDeriving WildcardInForeignExport WildcardInForeignImport WildcardInGADT1 WildcardInGADT2 WildcardInInstanceHead WildcardInInstanceSig WildcardInNewtype WildcardInPatSynSig WildcardInStandaloneDeriving WildcardInTypeFamilyInstanceRHS WildcardInTypeSynonymRHS saks_fail003 T15433a -} TcRnIllegalWildcardInType :: Maybe Name -- ^ the wildcard name, or 'Nothing' for an anonymous wildcard -> !BadAnonWildcardContext -> TcRnMessage {-| TcRnDuplicateFieldName is an error that occurs whenever there are duplicate field names in a record. Examples(s): None. Test cases: None. -} TcRnDuplicateFieldName :: !RecordFieldPart -> NE.NonEmpty RdrName -> TcRnMessage {-| TcRnIllegalViewPattern is an error that occurs whenever the ViewPatterns syntax is used but the ViewPatterns language extension is not enabled. Examples(s): data Foo = Foo { a :: Int } foo :: Foo -> Int foo (a -> l) = l -- not OK, the 'ViewPattern' extension is not enabled. Test cases: parser/should_fail/ViewPatternsFail -} TcRnIllegalViewPattern :: !(Pat GhcPs) -> TcRnMessage {-| TcRnCharLiteralOutOfRange is an error that occurs whenever a character is out of range. Examples(s): None Test cases: None -} TcRnCharLiteralOutOfRange :: !Char -> TcRnMessage {-| TcRnIllegalWildcardsInConstructor is an error that occurs whenever the record wildcards '..' are used inside a constructor without labeled fields. Examples(s): None Test cases: None -} TcRnIllegalWildcardsInConstructor :: !Name -> TcRnMessage {-| TcRnIgnoringAnnotations is a warning that occurs when the source code contains annotation pragmas but the platform in use does not support an external interpreter such as GHCi and therefore the annotations are ignored. Example(s): None Test cases: None -} TcRnIgnoringAnnotations :: [LAnnDecl GhcRn] -> TcRnMessage {-| TcRnAnnotationInSafeHaskell is an error that occurs if annotation pragmas are used in conjunction with Safe Haskell. Example(s): None Test cases: annotations/should_fail/T10826 -} TcRnAnnotationInSafeHaskell :: TcRnMessage {-| TcRnInvalidTypeApplication is an error that occurs when a visible type application is used with an expression that does not accept "specified" type arguments. Example(s): foo :: forall {a}. a -> a foo x = x bar :: () bar = let x = foo @Int 42 in () Test cases: overloadedrecflds/should_fail/overloadedlabelsfail03 typecheck/should_fail/ExplicitSpecificity1 typecheck/should_fail/ExplicitSpecificity10 typecheck/should_fail/ExplicitSpecificity2 typecheck/should_fail/T17173 typecheck/should_fail/VtaFail -} TcRnInvalidTypeApplication :: Type -> LHsWcType GhcRn -> TcRnMessage {-| TcRnTagToEnumMissingValArg is an error that occurs when the 'tagToEnum#' function is not applied to a single value argument. Example(s): tagToEnum# 1 2 Test cases: None -} TcRnTagToEnumMissingValArg :: TcRnMessage {-| TcRnTagToEnumUnspecifiedResTy is an error that occurs when the 'tagToEnum#' function is not given a concrete result type. Example(s): foo :: forall a. a foo = tagToEnum# 0# Test cases: typecheck/should_fail/tcfail164 -} TcRnTagToEnumUnspecifiedResTy :: Type -> TcRnMessage {-| TcRnTagToEnumResTyNotAnEnum is an error that occurs when the 'tagToEnum#' function is given a result type that is not an enumeration type. Example(s): foo :: Int -- not an enumeration TyCon foo = tagToEnum# 0# Test cases: typecheck/should_fail/tcfail164 -} TcRnTagToEnumResTyNotAnEnum :: Type -> TcRnMessage {-| TcRnTagToEnumResTyTypeData is an error that occurs when the 'tagToEnum#' function is given a result type that is headed by a @type data@ type, as the data constructors of a @type data@ do not exist at the term level. Example(s): type data Letter = A | B | C foo :: Letter foo = tagToEnum# 0# Test cases: type-data/should_fail/TDTagToEnum.hs -} TcRnTagToEnumResTyTypeData :: Type -> TcRnMessage {-| TcRnArrowIfThenElsePredDependsOnResultTy is an error that occurs when the predicate type of an ifThenElse expression in arrow notation depends on the type of the result. Example(s): None Test cases: None -} TcRnArrowIfThenElsePredDependsOnResultTy :: TcRnMessage {-| TcRnIllegalHsBootFileDecl is an error that occurs when an hs-boot file contains declarations that are not allowed, such as bindings. Example(s): None Test cases: None -} TcRnIllegalHsBootFileDecl :: TcRnMessage {-| TcRnRecursivePatternSynonym is an error that occurs when a pattern synonym is defined in terms of itself, either directly or indirectly. Example(s): pattern A = B pattern B = A Test cases: patsyn/should_fail/T16900 -} TcRnRecursivePatternSynonym :: LHsBinds GhcRn -> TcRnMessage {-| TcRnPartialTypeSigTyVarMismatch is an error that occurs when a partial type signature attempts to unify two different types. Example(s): f :: a -> b -> _ f x y = [x, y] Test cases: partial-sigs/should_fail/T14449 -} TcRnPartialTypeSigTyVarMismatch :: Name -- ^ first type variable -> Name -- ^ second type variable -> Name -- ^ function name -> LHsSigWcType GhcRn -> TcRnMessage {-| TcRnPartialTypeSigBadQuantifier is an error that occurs when a type variable being quantified over in the partial type signature of a function gets unified with a type that is free in that function's context. Example(s): foo :: Num a => a -> a foo xxx = g xxx where g :: forall b. Num b => _ -> b g y = xxx + y Test cases: partial-sig/should_fail/T14479 -} TcRnPartialTypeSigBadQuantifier :: Name -- ^ user-written name of type variable being quantified -> Name -- ^ function name -> Maybe Type -- ^ type the variable unified with, if known -> LHsSigWcType GhcRn -- ^ partial type signature -> TcRnMessage {-| TcRnMissingSignature is a warning that occurs when a top-level binding or a pattern synonym does not have a type signature. Controlled by the flags: -Wmissing-signatures -Wmissing-exported-signatures -Wmissing-pattern-synonym-signatures -Wmissing-exported-pattern-synonym-signatures -Wmissing-kind-signatures Test cases: T11077 (top-level bindings) T12484 (pattern synonyms) T19564 (kind signatures) -} TcRnMissingSignature :: MissingSignature -> Exported -> Bool -- ^ True: -Wmissing-signatures overrides -Wmissing-exported-signatures, -- or -Wmissing-pattern-synonym-signatures overrides -Wmissing-exported-pattern-synonym-signatures -> TcRnMessage {-| TcRnPolymorphicBinderMissingSig is a warning controlled by -Wmissing-local-signatures that occurs when a local polymorphic binding lacks a type signature. Example(s): id a = a Test cases: warnings/should_compile/T12574 -} TcRnPolymorphicBinderMissingSig :: Name -> Type -> TcRnMessage {-| TcRnOverloadedSig is an error that occurs when a binding group conflicts with the monomorphism restriction. Example(s): data T a = T a mono = ... where x :: Applicative f => f a T x = ... Test cases: typecheck/should_compile/T11339 -} TcRnOverloadedSig :: TcIdSigInfo -> TcRnMessage {-| TcRnTupleConstraintInst is an error that occurs whenever an instance for a tuple constraint is specified. Examples(s): class C m a class D m a f :: (forall a. Eq a => (C m a, D m a)) => m a f = undefined Test cases: quantified-constraints/T15334 -} TcRnTupleConstraintInst :: !Class -> TcRnMessage {-| TcRnAbstractClassInst is an error that occurs whenever an instance of an abstract class is specified. Examples(s): -- A.hs-boot module A where class C a -- B.hs module B where import {-# SOURCE #-} A instance C Int where -- A.hs module A where import B class C a where f :: a -- Main.hs import A main = print (f :: Int) Test cases: typecheck/should_fail/T13068 -} TcRnAbstractClassInst :: !Class -> TcRnMessage {-| TcRnNoClassInstHead is an error that occurs whenever an instance head is not headed by a class. Examples(s): instance c Test cases: typecheck/rename/T5513 typecheck/rename/T16385 -} TcRnNoClassInstHead :: !Type -> TcRnMessage {-| TcRnUserTypeError is an error that occurs due to a user's custom type error, which can be triggered by adding a `TypeError` constraint in a type signature or typeclass instance. Examples(s): f :: TypeError (Text "This is a type error") f = undefined Test cases: typecheck/should_fail/CustomTypeErrors02 typecheck/should_fail/CustomTypeErrors03 -} TcRnUserTypeError :: !Type -> TcRnMessage {-| TcRnConstraintInKind is an error that occurs whenever a constraint is specified in a kind. Examples(s): data Q :: Eq a => Type where {} Test cases: dependent/should_fail/T13895 polykinds/T16263 saks/should_fail/saks_fail004 typecheck/should_fail/T16059a typecheck/should_fail/T18714 -} TcRnConstraintInKind :: !Type -> TcRnMessage {-| TcRnUnboxedTupleTypeFuncArg is an error that occurs whenever an unboxed tuple or unboxed sum type is specified as a function argument, when the appropriate extension (`-XUnboxedTuples` or `-XUnboxedSums`) isn't enabled. Examples(s): -- T15073.hs import T15073a newtype Foo a = MkFoo a deriving P -- T15073a.hs class P a where p :: a -> (# a #) Test cases: deriving/should_fail/T15073.hs deriving/should_fail/T15073a.hs typecheck/should_fail/T16059d -} TcRnUnboxedTupleOrSumTypeFuncArg :: UnboxedTupleOrSum -- ^ whether this is an unboxed tuple or an unboxed sum -> !Type -> TcRnMessage {-| TcRnLinearFuncInKind is an error that occurs whenever a linear function is specified in a kind. Examples(s): data A :: * %1 -> * Test cases: linear/should_fail/LinearKind linear/should_fail/LinearKind2 linear/should_fail/LinearKind3 -} TcRnLinearFuncInKind :: !Type -> TcRnMessage {-| TcRnForAllEscapeError is an error that occurs whenever a quantified type's kind mentions quantified type variable. Examples(s): type T :: TYPE (BoxedRep l) data T = MkT Test cases: unlifted-datatypes/should_fail/UnlDataNullaryPoly -} TcRnForAllEscapeError :: !Type -> !Kind -> TcRnMessage {-| TcRnVDQInTermType is an error that occurs whenever a visible dependent quantification is specified in the type of a term. Examples(s): a = (undefined :: forall k -> k -> Type) @Int Test cases: dependent/should_fail/T15859 dependent/should_fail/T16326_Fail1 dependent/should_fail/T16326_Fail2 dependent/should_fail/T16326_Fail3 dependent/should_fail/T16326_Fail4 dependent/should_fail/T16326_Fail5 dependent/should_fail/T16326_Fail6 dependent/should_fail/T16326_Fail7 dependent/should_fail/T16326_Fail8 dependent/should_fail/T16326_Fail9 dependent/should_fail/T16326_Fail10 dependent/should_fail/T16326_Fail11 dependent/should_fail/T16326_Fail12 dependent/should_fail/T17687 dependent/should_fail/T18271 -} TcRnVDQInTermType :: !(Maybe Type) -> TcRnMessage {-| TcRnBadQuantPredHead is an error that occurs whenever a quantified predicate lacks a class or type variable head. Examples(s): class (forall a. A t a => A t [a]) => B t where type A t a :: Constraint Test cases: quantified-constraints/T16474 -} TcRnBadQuantPredHead :: !Type -> TcRnMessage {-| TcRnIllegalTupleConstraint is an error that occurs whenever an illegal tuple constraint is specified. Examples(s): g :: ((Show a, Num a), Eq a) => a -> a g = undefined Test cases: typecheck/should_fail/tcfail209a -} TcRnIllegalTupleConstraint :: !Type -> TcRnMessage {-| TcRnNonTypeVarArgInConstraint is an error that occurs whenever a non type-variable argument is specified in a constraint. Examples(s): data T instance Eq Int => Eq T Test cases: ghci/scripts/T13202 ghci/scripts/T13202a polykinds/T12055a typecheck/should_fail/T10351 typecheck/should_fail/T19187 typecheck/should_fail/T6022 typecheck/should_fail/T8883 -} TcRnNonTypeVarArgInConstraint :: !Type -> TcRnMessage {-| TcRnIllegalImplicitParam is an error that occurs whenever an illegal implicit parameter is specified. Examples(s): type Bla = ?x::Int data T = T instance Bla => Eq T Test cases: polykinds/T11466 typecheck/should_fail/T8912 typecheck/should_fail/tcfail041 typecheck/should_fail/tcfail211 typecheck/should_fail/tcrun045 -} TcRnIllegalImplicitParam :: !Type -> TcRnMessage {-| TcRnIllegalConstraintSynonymOfKind is an error that occurs whenever an illegal constraint synonym of kind is specified. Examples(s): type Showish = Show f :: (Showish a) => a -> a f = undefined Test cases: typecheck/should_fail/tcfail209 -} TcRnIllegalConstraintSynonymOfKind :: !Type -> TcRnMessage {-| TcRnIllegalClassInst is an error that occurs whenever a class instance is specified for a non-class. Examples(s): type C1 a = (Show (a -> Bool)) instance C1 Int where Test cases: polykinds/T13267 -} TcRnIllegalClassInst :: !TyConFlavour -> TcRnMessage {-| TcRnOversaturatedVisibleKindArg is an error that occurs whenever an illegal oversaturated visible kind argument is specified. Examples(s): type family F2 :: forall (a :: Type). Type where F2 @a = Maybe a Test cases: typecheck/should_fail/T15793 typecheck/should_fail/T16255 -} TcRnOversaturatedVisibleKindArg :: !Type -> TcRnMessage {-| TcRnBadAssociatedType is an error that occurs whenever a class doesn't have an associated type. Examples(s): $(do d <- instanceD (cxt []) (conT ''Eq `appT` conT ''Foo) [tySynInstD $ tySynEqn Nothing (conT ''Rep `appT` conT ''Foo) (conT ''Maybe)] return [d]) ======> instance Eq Foo where type Rep Foo = Maybe Test cases: th/T12387a -} TcRnBadAssociatedType :: {-Class-} !Name -> {-TyCon-} !Name -> TcRnMessage {-| TcRnForAllRankErr is an error that occurs whenever an illegal ranked type is specified. Examples(s): foo :: (a,b) -> (a~b => t) -> (a,b) foo p x = p Test cases: - ghci/should_run/T15806 - indexed-types/should_fail/SimpleFail15 - typecheck/should_fail/T11355 - typecheck/should_fail/T12083a - typecheck/should_fail/T12083b - typecheck/should_fail/T16059c - typecheck/should_fail/T16059e - typecheck/should_fail/T17213 - typecheck/should_fail/T18939_Fail - typecheck/should_fail/T2538 - typecheck/should_fail/T5957 - typecheck/should_fail/T7019 - typecheck/should_fail/T7019a - typecheck/should_fail/T7809 - typecheck/should_fail/T9196 - typecheck/should_fail/tcfail127 - typecheck/should_fail/tcfail184 - typecheck/should_fail/tcfail196 - typecheck/should_fail/tcfail197 -} TcRnForAllRankErr :: !Rank -> !Type -> TcRnMessage {-| TcRnMonomorphicBindings is a warning (controlled by -Wmonomorphism-restriction) that arise when the monomorphism restriction applies to the given bindings. Examples(s): {-# OPTIONS_GHC -Wmonomorphism-restriction #-} bar = 10 foo :: Int foo = bar main :: IO () main = print foo The example above emits the warning (for 'bar'), because without monomorphism restriction the inferred type for 'bar' is 'bar :: Num p => p'. This warning tells us that /if/ we were to enable '-XMonomorphismRestriction' we would make 'bar' less polymorphic, as its type would become 'bar :: Int', so GHC warns us about that. Test cases: typecheck/should_compile/T13785 -} TcRnMonomorphicBindings :: [Name] -> TcRnMessage {-| TcRnOrphanInstance is a warning (controlled by -Wwarn-orphans) that arises when a typeclass instance is an \"orphan\", i.e. if it appears in a module in which neither the class nor the type being instanced are declared in the same module. Examples(s): None Test cases: warnings/should_compile/T9178 typecheck/should_compile/T4912 -} TcRnOrphanInstance :: ClsInst -> TcRnMessage {-| TcRnFunDepConflict is an error that occurs when there are functional dependencies conflicts between instance declarations. Examples(s): None Test cases: typecheck/should_fail/T2307 typecheck/should_fail/tcfail096 typecheck/should_fail/tcfail202 -} TcRnFunDepConflict :: !UnitState -> NE.NonEmpty ClsInst -> TcRnMessage {-| TcRnDupInstanceDecls is an error that occurs when there are duplicate instance declarations. Examples(s): class Foo a where foo :: a -> Int instance Foo Int where foo = id instance Foo Int where foo = const 42 Test cases: cabal/T12733/T12733 typecheck/should_fail/tcfail035 typecheck/should_fail/tcfail023 backpack/should_fail/bkpfail18 typecheck/should_fail/TcNullaryTCFail typecheck/should_fail/tcfail036 typecheck/should_fail/tcfail073 module/mod51 module/mod52 module/mod44 -} TcRnDupInstanceDecls :: !UnitState -> NE.NonEmpty ClsInst -> TcRnMessage {-| TcRnConflictingFamInstDecls is an error that occurs when there are conflicting family instance declarations. Examples(s): None. Test cases: indexed-types/should_fail/ExplicitForAllFams4b indexed-types/should_fail/NoGood indexed-types/should_fail/Over indexed-types/should_fail/OverDirectThisMod indexed-types/should_fail/OverIndirectThisMod indexed-types/should_fail/SimpleFail11a indexed-types/should_fail/SimpleFail11b indexed-types/should_fail/SimpleFail11c indexed-types/should_fail/SimpleFail11d indexed-types/should_fail/SimpleFail2a indexed-types/should_fail/SimpleFail2b indexed-types/should_fail/T13092/T13092 indexed-types/should_fail/T13092c/T13092c indexed-types/should_fail/T14179 indexed-types/should_fail/T2334A indexed-types/should_fail/T2677 indexed-types/should_fail/T3330b indexed-types/should_fail/T4246 indexed-types/should_fail/T7102a indexed-types/should_fail/T9371 polykinds/T7524 typecheck/should_fail/UnliftedNewtypesOverlap -} TcRnConflictingFamInstDecls :: NE.NonEmpty FamInst -> TcRnMessage TcRnFamInstNotInjective :: InjectivityErrReason -> TyCon -> NE.NonEmpty CoAxBranch -> TcRnMessage {-| TcRnBangOnUnliftedType is a warning (controlled by -Wredundant-strictness-flags) that occurs when a strictness annotation is applied to an unlifted type. Example(s): data T = MkT !Int# -- Strictness flag has no effect on unlifted types Test cases: typecheck/should_compile/T20187a typecheck/should_compile/T20187b -} TcRnBangOnUnliftedType :: !Type -> TcRnMessage {-| TcRnLazyBangOnUnliftedType is a warning (controlled by -Wredundant-strictness-flags) that occurs when a lazy annotation is applied to an unlifted type. Example(s): data T = MkT ~Int# -- Lazy flag has no effect on unlifted types Test cases: typecheck/should_compile/T21951a typecheck/should_compile/T21951b -} TcRnLazyBangOnUnliftedType :: !Type -> TcRnMessage {-| TcRnMultipleDefaultDeclarations is an error that occurs when a module has more than one default declaration. Example: default (Integer, Int) default (Double, Float) -- 2nd default declaration not allowed Text cases: module/mod58 -} TcRnMultipleDefaultDeclarations :: [LDefaultDecl GhcRn] -> TcRnMessage {-| TcRnBadDefaultType is an error that occurs when a type used in a default declaration does not have an instance for any of the applicable classes. Example(s): data Foo default (Foo) Test cases: typecheck/should_fail/T11974b -} TcRnBadDefaultType :: Type -> [Class] -> TcRnMessage {-| TcRnPatSynBundledWithNonDataCon is an error that occurs when a module's export list bundles a pattern synonym with a type that is not a proper `data` or `newtype` construction. Example(s): module Foo (MyClass(.., P)) where pattern P = Nothing class MyClass a where foo :: a -> Int Test cases: patsyn/should_fail/export-class -} TcRnPatSynBundledWithNonDataCon :: TcRnMessage {-| TcRnPatSynBundledWithWrongType is an error that occurs when the export list of a module has a pattern synonym bundled with a type that does not match the type of the pattern synonym. Example(s): module Foo (R(P,x)) where data Q = Q Int data R = R pattern P{x} = Q x Text cases: patsyn/should_fail/export-ps-rec-sel patsyn/should_fail/export-type-synonym patsyn/should_fail/export-type -} TcRnPatSynBundledWithWrongType :: Type -> Type -> TcRnMessage {-| TcRnDupeModuleExport is a warning controlled by @-Wduplicate-exports@ that occurs when a module appears more than once in an export list. Example(s): module Foo (module Bar, module Bar) import Bar Text cases: None -} TcRnDupeModuleExport :: ModuleName -> TcRnMessage {-| TcRnExportedModNotImported is an error that occurs when an export list contains a module that is not imported. Example(s): None Text cases: module/mod135 module/mod8 rename/should_fail/rnfail028 backpack/should_fail/bkpfail48 -} TcRnExportedModNotImported :: ModuleName -> TcRnMessage {-| TcRnNullExportedModule is a warning controlled by -Wdodgy-exports that occurs when an export list contains a module that has no exports. Example(s): module Foo (module Bar) where import Bar () Test cases: None -} TcRnNullExportedModule :: ModuleName -> TcRnMessage {-| TcRnMissingExportList is a warning controlled by -Wmissing-export-lists that occurs when a module does not have an explicit export list. Example(s): None Test cases: typecheck/should_fail/MissingExportList03 -} TcRnMissingExportList :: ModuleName -> TcRnMessage {-| TcRnExportHiddenComponents is an error that occurs when an export contains constructor or class methods that are not visible. Example(s): None Test cases: None -} TcRnExportHiddenComponents :: IE GhcPs -> TcRnMessage {-| TcRnDuplicateExport is a warning (controlled by -Wduplicate-exports) that occurs when an identifier appears in an export list more than once. Example(s): None Test cases: module/MultiExport module/mod128 module/mod14 module/mod5 overloadedrecflds/should_fail/DuplicateExports patsyn/should_compile/T11959 -} TcRnDuplicateExport :: GreName -> IE GhcPs -> IE GhcPs -> TcRnMessage {-| TcRnExportedParentChildMismatch is an error that occurs when an export is bundled with a parent that it does not belong to Example(s): module Foo (T(a)) where data T a = True Test cases: module/T11970 module/T11970B module/mod17 module/mod3 overloadedrecflds/should_fail/NoParent -} TcRnExportedParentChildMismatch :: Name -> TyThing -> GreName -> [Name] -> TcRnMessage {-| TcRnConflictingExports is an error that occurs when different identifiers that have the same name are being exported by a module. Example(s): module Foo (Bar.f, module Baz) where import qualified Bar (f) import Baz (f) Test cases: module/mod131 module/mod142 module/mod143 module/mod144 module/mod145 module/mod146 module/mod150 module/mod155 overloadedrecflds/should_fail/T14953 overloadedrecflds/should_fail/overloadedrecfldsfail10 rename/should_fail/rnfail029 rename/should_fail/rnfail040 typecheck/should_fail/T16453E2 typecheck/should_fail/tcfail025 typecheck/should_fail/tcfail026 -} TcRnConflictingExports :: OccName -- ^ Occurrence name shared by both exports -> GreName -- ^ Name of first export -> GlobalRdrElt -- ^ Provenance for definition site of first export -> IE GhcPs -- ^ Export decl of first export -> GreName -- ^ Name of second export -> GlobalRdrElt -- ^ Provenance for definition site of second export -> IE GhcPs -- ^ Export decl of second export -> TcRnMessage {-| TcRnAmbiguousField is a warning controlled by -Wambiguous-fields occurring when a record update's type cannot be precisely determined. This will not be supported by -XDuplicateRecordFields in future releases. Example(s): data Person = MkPerson { personId :: Int, name :: String } data Address = MkAddress { personId :: Int, address :: String } bad1 x = x { personId = 4 } :: Person -- ambiguous bad2 (x :: Person) = x { personId = 4 } -- ambiguous good x = (x :: Person) { personId = 4 } -- not ambiguous Test cases: overloadedrecflds/should_fail/overloadedrecfldsfail06 -} TcRnAmbiguousField :: HsExpr GhcRn -- ^ Field update -> TyCon -- ^ Record type -> TcRnMessage {-| TcRnMissingFields is a warning controlled by -Wmissing-fields occurring when the intialisation of a record is missing one or more (lazy) fields. Example(s): data Rec = Rec { a :: Int, b :: String, c :: Bool } x = Rec { a = 1, b = "two" } -- missing field 'c' Test cases: deSugar/should_compile/T13870 deSugar/should_compile/ds041 patsyn/should_compile/T11283 rename/should_compile/T5334 rename/should_compile/T12229 rename/should_compile/T5892a warnings/should_fail/WerrorFail2 -} TcRnMissingFields :: ConLike -> [(FieldLabelString, TcType)] -> TcRnMessage {-| TcRnFieldUpdateInvalidType is an error occurring when an updated field's type mentions something that is outside the universally quantified variables of the data constructor, such as an existentially quantified type. Example(s): data X = forall a. MkX { f :: a } x = (MkX ()) { f = False } Test cases: patsyn/should_fail/records-exquant typecheck/should_fail/T3323 -} TcRnFieldUpdateInvalidType :: [(FieldLabelString,TcType)] -> TcRnMessage {-| TcRnNoConstructorHasAllFields is an error that occurs when a record update has fields that no single constructor encompasses. Example(s): data Foo = A { x :: Bool } | B { y :: Int } foo = (A False) { x = True, y = 5 } Test cases: overloadedrecflds/should_fail/overloadedrecfldsfail08 patsyn/should_fail/mixed-pat-syn-record-sels typecheck/should_fail/T7989 -} TcRnNoConstructorHasAllFields :: [FieldLabelString] -> TcRnMessage {- TcRnMixedSelectors is an error for when a mixture of pattern synonym and record selectors are used in the same record update block. Example(s): data Rec = Rec { foo :: Int, bar :: String } pattern Pat { f1, f2 } = Rec { foo = f1, bar = f2 } illegal :: Rec -> Rec illegal r = r { f1 = 1, bar = "two" } Test cases: patsyn/should_fail/records-mixing-fields -} TcRnMixedSelectors :: Name -- ^ Record -> [Id] -- ^ Record selectors -> Name -- ^ Pattern synonym -> [Id] -- ^ Pattern selectors -> TcRnMessage {- TcRnMissingStrictFields is an error occurring when a record field marked as strict is omitted when constructing said record. Example(s): data R = R { strictField :: !Bool, nonStrict :: Int } x = R { nonStrict = 1 } Test cases: typecheck/should_fail/T18869 typecheck/should_fail/tcfail085 typecheck/should_fail/tcfail112 -} TcRnMissingStrictFields :: ConLike -> [(FieldLabelString, TcType)] -> TcRnMessage {- TcRnNoPossibleParentForFields is an error thrown when the fields used in a record update block do not all belong to any one type. Example(s): data R1 = R1 { x :: Int, y :: Int } data R2 = R2 { y :: Int, z :: Int } update r = r { x = 1, y = 2, z = 3 } Test cases: overloadedrecflds/should_fail/overloadedrecfldsfail01 overloadedrecflds/should_fail/overloadedrecfldsfail14 -} TcRnNoPossibleParentForFields :: [LHsRecUpdField GhcRn] -> TcRnMessage {- TcRnBadOverloadedRecordUpdate is an error for a record update that cannot be pinned down to any one constructor and thus must be given a type signature. Example(s): data R1 = R1 { x :: Int } data R2 = R2 { x :: Int } update r = r { x = 1 } -- needs a type signature Test cases: overloadedrecflds/should_fail/overloadedrecfldsfail01 -} TcRnBadOverloadedRecordUpdate :: [LHsRecUpdField GhcRn] -> TcRnMessage {- TcRnStaticFormNotClosed is an error pertaining to terms that are marked static using the -XStaticPointers extension but which are not closed terms. Example(s): f x = static x Test cases: rename/should_fail/RnStaticPointersFail01 rename/should_fail/RnStaticPointersFail03 -} TcRnStaticFormNotClosed :: Name -> NotClosedReason -> TcRnMessage {-| TcRnSpecialClassInst is an error that occurs when a user attempts to define an instance for a built-in typeclass such as 'Coercible', 'Typeable', or 'KnownNat', outside of a signature file. Test cases: deriving/should_fail/T9687 deriving/should_fail/T14916 polykinds/T8132 typecheck/should_fail/TcCoercibleFail2 typecheck/should_fail/T12837 typecheck/should_fail/T14390 -} TcRnSpecialClassInst :: !Class -> !Bool -- ^ Whether the error is due to Safe Haskell being enabled -> TcRnMessage {-| TcRnUselessTypeable is a warning (controlled by -Wderiving-typeable) that occurs when trying to derive an instance of the 'Typeable' class. Deriving 'Typeable' is no longer necessary (hence the \"useless\") as all types automatically derive 'Typeable' in modern GHC versions. Example(s): None. Test cases: warnings/should_compile/DerivingTypeable -} TcRnUselessTypeable :: TcRnMessage {-| TcRnDerivingDefaults is a warning (controlled by -Wderiving-defaults) that occurs when both 'DeriveAnyClass' and 'GeneralizedNewtypeDeriving' are enabled, and therefore GHC defaults to 'DeriveAnyClass', which might not be what the user wants. Example(s): None. Test cases: typecheck/should_compile/T15839a deriving/should_compile/T16179 -} TcRnDerivingDefaults :: !Class -> TcRnMessage {-| TcRnNonUnaryTypeclassConstraint is an error that occurs when GHC encounters a non-unary constraint when trying to derive a typeclass. Example(s): class A deriving instance A data B deriving A -- We cannot derive A, is not unary (i.e. 'class A a'). Test cases: deriving/should_fail/T7959 deriving/should_fail/drvfail005 deriving/should_fail/drvfail009 deriving/should_fail/drvfail006 -} TcRnNonUnaryTypeclassConstraint :: !(LHsSigType GhcRn) -> TcRnMessage {-| TcRnPartialTypeSignatures is a warning (controlled by -Wpartial-type-signatures) that occurs when a wildcard '_' is found in place of a type in a signature or a type class derivation Example(s): foo :: _ -> Int foo = ... deriving instance _ => Eq (Foo a) Test cases: dependent/should_compile/T11241 dependent/should_compile/T15076 dependent/should_compile/T14880-2 typecheck/should_compile/T17024 typecheck/should_compile/T10072 partial-sigs/should_fail/TidyClash2 partial-sigs/should_fail/Defaulting1MROff partial-sigs/should_fail/WildcardsInPatternAndExprSig partial-sigs/should_fail/T10615 partial-sigs/should_fail/T14584a partial-sigs/should_fail/TidyClash partial-sigs/should_fail/T11122 partial-sigs/should_fail/T14584 partial-sigs/should_fail/T10045 partial-sigs/should_fail/PartialTypeSignaturesDisabled partial-sigs/should_fail/T10999 partial-sigs/should_fail/ExtraConstraintsWildcardInExpressionSignature partial-sigs/should_fail/ExtraConstraintsWildcardInPatternSplice partial-sigs/should_fail/WildcardInstantiations partial-sigs/should_run/T15415 partial-sigs/should_compile/T10463 partial-sigs/should_compile/T15039a partial-sigs/should_compile/T16728b partial-sigs/should_compile/T15039c partial-sigs/should_compile/T10438 partial-sigs/should_compile/SplicesUsed partial-sigs/should_compile/T18008 partial-sigs/should_compile/ExprSigLocal partial-sigs/should_compile/T11339a partial-sigs/should_compile/T11670 partial-sigs/should_compile/WarningWildcardInstantiations partial-sigs/should_compile/T16728 partial-sigs/should_compile/T12033 partial-sigs/should_compile/T15039b partial-sigs/should_compile/T10403 partial-sigs/should_compile/T11192 partial-sigs/should_compile/T16728a partial-sigs/should_compile/TypedSplice partial-sigs/should_compile/T15039d partial-sigs/should_compile/T11016 partial-sigs/should_compile/T13324_compile2 linear/should_fail/LinearPartialSig polykinds/T14265 polykinds/T14172 -} TcRnPartialTypeSignatures :: !SuggestPartialTypeSignatures -> !ThetaType -> TcRnMessage {-| TcRnCannotDeriveInstance is an error that occurs every time a typeclass instance can't be derived. The 'DeriveInstanceErrReason' will contain the specific reason this error arose. Example(s): None. Test cases: generics/T10604/T10604_no_PolyKinds deriving/should_fail/drvfail009 deriving/should_fail/drvfail-functor2 deriving/should_fail/T10598_fail3 deriving/should_fail/deriving-via-fail2 deriving/should_fail/deriving-via-fail deriving/should_fail/T16181 -} TcRnCannotDeriveInstance :: !Class -- ^ The typeclass we are trying to derive -- an instance for -> [Type] -- ^ The typeclass arguments, if any. -> !(Maybe (DerivStrategy GhcTc)) -- ^ The derivation strategy, if any. -> !UsingGeneralizedNewtypeDeriving -- ^ Is '-XGeneralizedNewtypeDeriving' enabled? -> !DeriveInstanceErrReason -- ^ The specific reason why we couldn't derive -- an instance for the class. -> TcRnMessage {-| TcRnLazyGADTPattern is an error that occurs when a user writes a nested GADT pattern match inside a lazy (~) pattern. Test case: gadt/lazypat -} TcRnLazyGADTPattern :: TcRnMessage {-| TcRnArrowProcGADTPattern is an error that occurs when a user writes a GADT pattern inside arrow proc notation. Test case: arrows/should_fail/arrowfail004. -} TcRnArrowProcGADTPattern :: TcRnMessage {-| TcRnForallIdentifier is a warning (controlled with -Wforall-identifier) that occurs when a definition uses 'forall' as an identifier. Example: forall x = () g forall = () Test cases: T20609 T20609a T20609b T20609c T20609d -} TcRnForallIdentifier :: RdrName -> TcRnMessage {-| TcRnTypeEqualityOutOfScope is a warning (controlled by -Wtype-equality-out-of-scope) that occurs when the type equality (a ~ b) is not in scope. Test case: T18862b -} TcRnTypeEqualityOutOfScope :: TcRnMessage {-| TcRnTypeEqualityRequiresOperators is a warning (controlled by -Wtype-equality-requires-operators) that occurs when the type equality (a ~ b) is used without the TypeOperators extension. Example: {-# LANGUAGE NoTypeOperators #-} f :: (a ~ b) => a -> b Test case: T18862a -} TcRnTypeEqualityRequiresOperators :: TcRnMessage {-| TcRnIllegalTypeOperator is an error that occurs when a type operator is used without the TypeOperators extension. Example: {-# LANGUAGE NoTypeOperators #-} f :: Vec a n -> Vec a m -> Vec a (n + m) Test case: T12811 -} TcRnIllegalTypeOperator :: !SDoc -> !RdrName -> TcRnMessage {-| TcRnIllegalTypeOperatorDecl is an error that occurs when a type or class operator is declared without the TypeOperators extension. See Note [Type and class operator definitions] Example: {-# LANGUAGE Haskell2010 #-} {-# LANGUAGE MultiParamTypeClasses #-} module T3265 where data a :+: b = Left a | Right b class a :*: b where {} Test cases: T3265, tcfail173 -} TcRnIllegalTypeOperatorDecl :: !RdrName -> TcRnMessage {-| TcRnGADTMonoLocalBinds is a warning controlled by -Wgadt-mono-local-binds that occurs when pattern matching on a GADT when -XMonoLocalBinds is off. Example(s): None Test cases: T20485, T20485a -} TcRnGADTMonoLocalBinds :: TcRnMessage {-| The TcRnNotInScope constructor is used for various not-in-scope errors. See 'NotInScopeError' for more details. -} TcRnNotInScope :: NotInScopeError -- ^ what the problem is -> RdrName -- ^ the name that is not in scope -> [ImportError] -- ^ import errors that are relevant -> [GhcHint] -- ^ hints, e.g. enable DataKinds to refer to a promoted data constructor -> TcRnMessage {-| TcRnUntickedPromotedThing is a warning (controlled with -Wunticked-promoted-constructors) that is triggered by an unticked occurrence of a promoted data constructor. Examples: data A = MkA type family F (a :: A) where { F MkA = Bool } type B = [ Int, Bool ] Test cases: T9778, T19984. -} TcRnUntickedPromotedThing :: UntickedPromotedThing -> TcRnMessage {-| TcRnIllegalBuiltinSyntax is an error that occurs when built-in syntax appears in an unexpected location, e.g. as a data constructor or in a fixity declaration. Examples: infixl 5 : data P = (,) Test cases: rnfail042, T14907b, T15124, T15233. -} TcRnIllegalBuiltinSyntax :: SDoc -- ^ what kind of thing this is (a binding, fixity declaration, ...) -> RdrName -> TcRnMessage -- TODO: remove the SDoc argument. {-| TcRnWarnDefaulting is a warning (controlled by -Wtype-defaults) that is triggered whenever a Wanted typeclass constraint is solving through the defaulting of a type variable. Example: one = show 1 -- We get Wanteds Show a0, Num a0, and default a0 to Integer. Test cases: none (which are really specific to defaulting), but see e.g. tcfail204. -} TcRnWarnDefaulting :: [Ct] -- ^ Wanted constraints in which defaulting occurred -> Maybe TyVar -- ^ The type variable being defaulted -> Type -- ^ The default type -> TcRnMessage {-| TcRnIncorrectNameSpace is an error that occurs when a 'Name' is used in the incorrect 'NameSpace', e.g. a type constructor or class used in a term, or a term variable used in a type. Example: f x = Int Test cases: T18740a, T20884. -} TcRnIncorrectNameSpace :: Name -> Bool -- ^ whether the error is happening -- in a Template Haskell tick -- (so we should give a Template Haskell hint) -> TcRnMessage {- TcRnForeignImportPrimExtNotSet is an error occurring when a foreign import is declared using the @prim@ calling convention without having turned on the -XGHCForeignImportPrim extension. Example(s): foreign import prim "foo" foo :: ByteArray# -> (# Int#, Int# #) Test cases: ffi/should_fail/T20116 -} TcRnForeignImportPrimExtNotSet :: ForeignImport GhcRn -> TcRnMessage {- TcRnForeignImportPrimSafeAnn is an error declaring that the safe/unsafe annotation should not be used with @prim@ foreign imports. Example(s): foreign import prim unsafe "my_primop_cmm" :: ... Test cases: None -} TcRnForeignImportPrimSafeAnn :: ForeignImport GhcRn -> TcRnMessage {- TcRnForeignFunctionImportAsValue is an error explaining that foreign @value@ imports cannot have function types. Example(s): foreign import capi "math.h value sqrt" f :: CInt -> CInt Test cases: ffi/should_fail/capi_value_function -} TcRnForeignFunctionImportAsValue :: ForeignImport GhcRn -> TcRnMessage {- TcRnFunPtrImportWithoutAmpersand is a warning controlled by @-Wdodgy-foreign-imports@ that informs the user of a possible missing @&@ in the declaration of a foreign import with a 'FunPtr' return type. Example(s): foreign import ccall "f" f :: FunPtr (Int -> IO ()) Test cases: ffi/should_compile/T1357 -} TcRnFunPtrImportWithoutAmpersand :: ForeignImport GhcRn -> TcRnMessage {- TcRnIllegalForeignDeclBackend is an error occurring when a foreign import declaration is not compatible with the code generation backend being used. Example(s): None Test cases: None -} TcRnIllegalForeignDeclBackend :: Either (ForeignExport GhcRn) (ForeignImport GhcRn) -> Backend -> ExpectedBackends -> TcRnMessage {- TcRnUnsupportedCallConv informs the user that the calling convention specified for a foreign export declaration is not compatible with the target platform. It is a warning controlled by @-Wunsupported-calling-conventions@ in the case of @stdcall@ but is otherwise considered an error. Example(s): None Test cases: None -} TcRnUnsupportedCallConv :: Either (ForeignExport GhcRn) (ForeignImport GhcRn) -> UnsupportedCallConvention -> TcRnMessage {- TcRnIllegalForeignType is an error for when a type appears in a foreign function signature that is not compatible with the FFI. Example(s): None Test cases: ffi/should_fail/T3066 ffi/should_fail/ccfail004 ffi/should_fail/T10461 ffi/should_fail/T7506 ffi/should_fail/T5664 safeHaskell/ghci/p6 safeHaskell/safeLanguage/SafeLang08 ffi/should_fail/T16702 linear/should_fail/LinearFFI ffi/should_fail/T7243 -} TcRnIllegalForeignType :: !(Maybe ArgOrResult) -> !IllegalForeignTypeReason -> TcRnMessage {- TcRnInvalidCIdentifier indicates a C identifier that is not valid. Example(s): foreign import prim safe "not valid" cmm_test2 :: Int# -> Int# Test cases: th/T10638 -} TcRnInvalidCIdentifier :: !CLabelString -> TcRnMessage {- TcRnExpectedValueId is an error occurring when something that is not a value identifier is used where one is expected. Example(s): none Test cases: none -} TcRnExpectedValueId :: !TcTyThing -> TcRnMessage {- TcRnNotARecordSelector is an error for when something that is not a record selector is used in a record pattern. Example(s): data Rec = MkRec { field :: Int } r = Mkrec 1 r' = r { notAField = 2 } Test cases: rename/should_fail/rnfail054 typecheck/should_fail/tcfail114 -} TcRnNotARecordSelector :: !Name -> TcRnMessage {- TcRnRecSelectorEscapedTyVar is an error indicating that a record field selector containing an existential type variable is used as a function rather than in a pattern match. Example(s): data Rec = forall a. Rec { field :: a } field (Rec True) Test cases: patsyn/should_fail/records-exquant typecheck/should_fail/T3176 -} TcRnRecSelectorEscapedTyVar :: !OccName -> TcRnMessage {- TcRnPatSynNotBidirectional is an error for when a non-bidirectional pattern synonym is used as a constructor. Example(s): pattern Five :: Int pattern Five <- 5 five = Five Test cases: patsyn/should_fail/records-no-uni-update patsyn/should_fail/records-no-uni-update2 -} TcRnPatSynNotBidirectional :: !Name -> TcRnMessage {- TcRnSplicePolymorphicLocalVar is the error that occurs when the expression inside typed template haskell brackets is a polymorphic local variable. Example(s): x = \(y :: forall a. a -> a) -> [|| y ||] Test cases: quotes/T10384 -} TcRnSplicePolymorphicLocalVar :: !Id -> TcRnMessage {- TcRnIllegalDerivingItem is an error for when something other than a type class appears in a deriving statement. Example(s): data X = X deriving Int Test cases: deriving/should_fail/T5922 -} TcRnIllegalDerivingItem :: !(LHsSigType GhcRn) -> TcRnMessage {- TcRnUnexpectedAnnotation indicates the erroroneous use of an annotation such as strictness, laziness, or unpacking. Example(s): data T = T { t :: Maybe {-# UNPACK #-} Int } data C = C { f :: !IntMap Int } Test cases: parser/should_fail/unpack_inside_type typecheck/should_fail/T7210 -} TcRnUnexpectedAnnotation :: !(HsType GhcRn) -> !HsSrcBang -> TcRnMessage {- TcRnIllegalRecordSyntax is an error indicating an illegal use of record syntax. Example(s): data T = T Int { field :: Int } Test cases: rename/should_fail/T7943 rename/should_fail/T9077 -} TcRnIllegalRecordSyntax :: !(HsType GhcRn) -> TcRnMessage {- TcRnUnexpectedTypeSplice is an error for a typed template haskell splice appearing unexpectedly. Example(s): none Test cases: none -} TcRnUnexpectedTypeSplice :: !(HsType GhcRn) -> TcRnMessage {- TcRnInvalidVisibleKindArgument is an error for a kind application on a target type that cannot accept it. Example(s): bad :: Int @Type bad = 1 type Foo :: forall a {b}. a -> b -> b type Foo x y = y type Bar = Foo @Bool @Int True 42 Test cases: indexed-types/should_fail/T16356_Fail3 typecheck/should_fail/ExplicitSpecificity7 typecheck/should_fail/T12045b typecheck/should_fail/T12045c typecheck/should_fail/T15592a typecheck/should_fail/T15816 -} TcRnInvalidVisibleKindArgument :: !(LHsType GhcRn) -- ^ The visible kind argument -> !Type -- ^ Target of the kind application -> TcRnMessage {- TcRnTooManyBinders is an error for a type constructor that is declared with more arguments then its kind specifies. Example(s): type T :: Type -> (Type -> Type) -> Type data T a (b :: Type -> Type) x1 (x2 :: Type -> Type) Test cases: saks/should_fail/saks_fail008 -} TcRnTooManyBinders :: !Kind -> ![LHsTyVarBndr () GhcRn] -> TcRnMessage {- TcRnDifferentNamesForTyVar is an error that indicates different names being used for the same type variable. Example(s): data SameKind :: k -> k -> * data Q (a :: k1) (b :: k2) c = MkQ (SameKind a b) Test cases: polykinds/T11203 polykinds/T11821a saks/should_fail/T20916 typecheck/should_fail/T17566b typecheck/should_fail/T17566c -} TcRnDifferentNamesForTyVar :: !Name -> !Name -> TcRnMessage {- TcRnInvalidReturnKind is an error for a data declaration that has a kind signature with an invalid result kind. Example(s): data family Foo :: Constraint Test cases: typecheck/should_fail/T14048b typecheck/should_fail/UnliftedNewtypesConstraintFamily typecheck/should_fail/T12729 typecheck/should_fail/T15883 typecheck/should_fail/T16829a typecheck/should_fail/T16829b typecheck/should_fail/UnliftedNewtypesNotEnabled typecheck/should_fail/tcfail079 -} TcRnInvalidReturnKind :: !DataSort -- ^ classification of thing being returned -> !AllowedDataResKind -- ^ allowed kind -> !Kind -- ^ the return kind -> !(Maybe SuggestUnliftedTypes) -- ^ suggested extension -> TcRnMessage {- TcRnClassKindNotConstraint is an error for a type class that has a kind that is not equivalent to Constraint. Example(s): type C :: Type -> Type class C a Test cases: saks/should_fail/T16826 -} TcRnClassKindNotConstraint :: !Kind -> TcRnMessage {- TcRnUnpromotableThing is an error that occurs when the user attempts to use the promoted version of something which is not promotable. Example(s): data T :: T -> * data X a where MkX :: Show a => a -> X a foo :: Proxy ('MkX 'True) foo = Proxy Test cases: dependent/should_fail/PromotedClass dependent/should_fail/T14845_fail1 dependent/should_fail/T14845_fail2 dependent/should_fail/T15215 dependent/should_fail/T13780c dependent/should_fail/T15245 polykinds/T5716 polykinds/T5716a polykinds/T6129 polykinds/T7433 patsyn/should_fail/T11265 patsyn/should_fail/T9161-1 patsyn/should_fail/T9161-2 dependent/should_fail/SelfDep polykinds/PolyKinds06 polykinds/PolyKinds07 polykinds/T13625 polykinds/T15116 polykinds/T15116a saks/should_fail/T16727a saks/should_fail/T16727b rename/should_fail/T12686 -} TcRnUnpromotableThing :: !Name -> !PromotionErr -> TcRnMessage {- TcRnMatchesHaveDiffNumArgs is an error occurring when something has matches that have different numbers of arguments Example(s): foo x = True foo x y = False Test cases: rename/should_fail/rnfail045 typecheck/should_fail/T20768_fail -} TcRnMatchesHaveDiffNumArgs :: !(HsMatchContext GhcTc) -- ^ Pattern match specifics -> !MatchArgBadMatches -> TcRnMessage {- TcRnCannotBindScopedTyVarInPatSig is an error stating that scoped type variables cannot be used in pattern bindings. Example(s): let (x :: a) = 5 Test cases: typecheck/should_compile/tc141 -} TcRnCannotBindScopedTyVarInPatSig :: !(NE.NonEmpty (Name, TcTyVar)) -> TcRnMessage {- TcRnCannotBindTyVarsInPatBind is an error for when type variables are introduced in a pattern binding Example(s): Just @a x = Just True Test cases: typecheck/should_fail/TyAppPat_PatternBinding typecheck/should_fail/TyAppPat_PatternBindingExistential -} TcRnCannotBindTyVarsInPatBind :: !(NE.NonEmpty (Name, TcTyVar)) -> TcRnMessage {- TcRnTooManyTyArgsInConPattern is an error occurring when a constructor pattern has more than the expected number of type arguments Example(s): f (Just @Int @Bool x) = x Test cases: typecheck/should_fail/TyAppPat_TooMany typecheck/should_fail/T20443b -} TcRnTooManyTyArgsInConPattern :: !ConLike -> !Int -- ^ Expected number of args -> !Int -- ^ Actual number of args -> TcRnMessage {- TcRnMultipleInlinePragmas is a warning signifying that multiple inline pragmas reference the same definition. Example(s): {-# INLINE foo #-} {-# INLINE foo #-} foo :: Bool -> Bool foo = id Test cases: none -} TcRnMultipleInlinePragmas :: !Id -- ^ Target of the pragmas -> !(LocatedA InlinePragma) -- ^ The first pragma -> !(NE.NonEmpty (LocatedA InlinePragma)) -- ^ Other pragmas -> TcRnMessage {- TcRnUnexpectedPragmas is a warning that occurs when unexpected pragmas appear in the source. Example(s): Test cases: none -} TcRnUnexpectedPragmas :: !Id -> !(NE.NonEmpty (LSig GhcRn)) -> TcRnMessage {- TcRnNonOverloadedSpecialisePragma is a warning for a specialise pragma being placed on a definition that is not overloaded. Example(s): {-# SPECIALISE foo :: Bool -> Bool #-} foo :: Bool -> Bool foo = id Test cases: simplCore/should_compile/T8537 typecheck/should_compile/T10504 -} TcRnNonOverloadedSpecialisePragma :: !(LIdP GhcRn) -> TcRnMessage {- TcRnSpecialiseNotVisible is a warning that occurs when the subject of a SPECIALISE pragma has a definition that is not visible from the current module. Example(s): none Test cases: none -} TcRnSpecialiseNotVisible :: !Name -> TcRnMessage {- TcRnNameByTemplateHaskellQuote is an error that occurs when one tries to use a Template Haskell splice to define a top-level identifier with an already existing name. (See issue #13968 (closed) on GHC's issue tracker for more details) Example(s): $(pure [ValD (VarP 'succ) (NormalB (ConE 'True)) []]) Test cases: T13968 -} TcRnNameByTemplateHaskellQuote :: !RdrName -> TcRnMessage {- TcRnIllegalBindingOfBuiltIn is an error that occurs when one uses built-in syntax for data constructors or class names. Use an OccName here because we don't want to print Prelude.(,) Test cases: rename/should_fail/T14907b rename/should_fail/rnfail042 -} TcRnIllegalBindingOfBuiltIn :: !OccName -> TcRnMessage {- TcRnPragmaWarning is a warning that can happen when usage of something is warned or deprecated by pragma. Test cases: DeprU T5281 T5867 rn050 rn066 (here is a warning, not deprecation) T3303 -} TcRnPragmaWarning :: { TcRnMessage -> OccName pragma_warning_occ :: OccName, TcRnMessage -> WarningTxt GhcRn pragma_warning_msg :: WarningTxt GhcRn, TcRnMessage -> ModuleName pragma_warning_import_mod :: ModuleName, TcRnMessage -> ModuleName pragma_warning_defined_mod :: ModuleName } -> TcRnMessage {-| TcRnIllegalHsigDefaultMethods is an error that occurs when a binding for a class default method is provided in a Backpack signature file. Test case: bkpfail40 -} TcRnIllegalHsigDefaultMethods :: !Name -- ^ 'Name' of the class -> NE.NonEmpty (LHsBind GhcRn) -- ^ default methods -> TcRnMessage {-| TcRnBadGenericMethod This test ensures that if you provide a "more specific" type signatures for the default method, you must also provide a binding. Example: {-# LANGUAGE DefaultSignatures #-} class C a where meth :: a default meth :: Num a => a meth = 0 Test case: testsuite/tests/typecheck/should_fail/MissingDefaultMethodBinding.hs -} TcRnBadGenericMethod :: !Name -- ^ 'Name' of the class -> !Name -- ^ Problematic method -> TcRnMessage {-| TcRnWarningMinimalDefIncomplete is a warning that one must specify which methods must be implemented by all instances. Example: class Cheater a where -- WARNING LINE cheater :: a {-# MINIMAL #-} -- warning! Test case: testsuite/tests/warnings/minimal/WarnMinimal.hs: -} TcRnWarningMinimalDefIncomplete :: ClassMinimalDef -> TcRnMessage {-| TcRnDefaultMethodForPragmaLacksBinding is an error that occurs when a default method pragma is missing an accompanying binding. Test cases: testsuite/tests/typecheck/should_fail/T5084.hs testsuite/tests/typecheck/should_fail/T2354.hs -} TcRnDefaultMethodForPragmaLacksBinding :: Id -- ^ method -> Sig GhcRn -- ^ the pragma -> TcRnMessage {-| TcRnIgnoreSpecialisePragmaOnDefMethod is a warning that occurs when a specialise pragma is put on a default method. Test cases: none -} TcRnIgnoreSpecialisePragmaOnDefMethod :: !Name -> TcRnMessage {-| TcRnBadMethodErr is an error that happens when one attempts to provide a method in a class instance, when the class doesn't have a method by that name. Test case: testsuite/tests/th/T12387 -} TcRnBadMethodErr :: { TcRnMessage -> Name badMethodErrClassName :: !Name , TcRnMessage -> Name badMethodErrMethodName :: !Name } -> TcRnMessage {-| TcRnNoExplicitAssocTypeOrDefaultDeclaration is an error that occurs when a class instance does not provide an expected associated type or default declaration. Test cases: testsuite/tests/deriving/should_compile/T14094 testsuite/tests/indexed-types/should_compile/Simple2 testsuite/tests/typecheck/should_compile/tc254 -} TcRnNoExplicitAssocTypeOrDefaultDeclaration :: Name -> TcRnMessage {-| TcRnIllegalNewtype is an error that occurs when a newtype: * Does not have exactly one field, or * is non-linear, or * is a GADT, or * has a context in its constructor's type, or * has existential type variables in its constructor's type, or * has strictness annotations. Test cases: testsuite/tests/gadt/T14719 testsuite/tests/indexed-types/should_fail/T14033 testsuite/tests/indexed-types/should_fail/T2334A testsuite/tests/linear/should_fail/LinearGADTNewtype testsuite/tests/parser/should_fail/readFail008 testsuite/tests/polykinds/T11459 testsuite/tests/typecheck/should_fail/T15523 testsuite/tests/typecheck/should_fail/T15796 testsuite/tests/typecheck/should_fail/T17955 testsuite/tests/typecheck/should_fail/T18891a testsuite/tests/typecheck/should_fail/T21447 testsuite/tests/typecheck/should_fail/tcfail156 -} TcRnIllegalNewtype :: DataCon -> Bool -- ^ True if linear types enabled -> IllegalNewtypeReason -> TcRnMessage {-| TcRnIllegalTypeData is an error that occurs when a @type data@ declaration occurs without the TypeOperators extension. See Note [Type data declarations] Test case: testsuite/tests/type-data/should_fail/TDNoPragma -} TcRnIllegalTypeData :: TcRnMessage {-| TcRnTypeDataForbids is an error that occurs when a @type data@ declaration contains @data@ declaration features that are forbidden in a @type data@ declaration. See Note [Type data declarations] Test cases: testsuite/tests/type-data/should_fail/TDDeriving testsuite/tests/type-data/should_fail/TDRecordsGADT testsuite/tests/type-data/should_fail/TDRecordsH98 testsuite/tests/type-data/should_fail/TDStrictnessGADT testsuite/tests/type-data/should_fail/TDStrictnessH98 -} TcRnTypeDataForbids :: !TypeDataForbids -> TcRnMessage {-| TcRnTypedTHWithPolyType is an error that signifies the illegal use of a polytype in a typed template haskell expression. Example(s): bad :: (forall a. a -> a) -> () bad = $$( [|| \_ -> () ||] ) Test cases: th/T11452 -} TcRnTypedTHWithPolyType :: !TcType -> TcRnMessage {-| TcRnSpliceThrewException is an error that occurrs when running a template haskell splice throws an exception. Example(s): Test cases: annotations/should_fail/annfail12 perf/compiler/MultiLayerModulesTH_Make perf/compiler/MultiLayerModulesTH_OneShot th/T10796b th/T19470 th/T19709d th/T5358 th/T5976 th/T7276a th/T8987 th/TH_exn1 th/TH_exn2 th/TH_runIO -} TcRnSpliceThrewException :: !SplicePhase -> !SomeException -> !String -- ^ Result of showing the exception (cannot be done safely outside IO) -> !(LHsExpr GhcTc) -> !Bool -- True <=> Print the expression -> TcRnMessage {-| TcRnInvalidTopDecl is a template haskell error occurring when one of the 'Dec's passed to 'addTopDecls' is not a function, value, annotation, or foreign import declaration. Example(s): Test cases: -} TcRnInvalidTopDecl :: !(HsDecl GhcPs) -> TcRnMessage {-| TcRnNonExactName is a template haskell error for when a declaration being added is bound to a name that is not fully known. Example(s): Test cases: -} TcRnNonExactName :: !RdrName -> TcRnMessage {-| TcRnAddInvalidCorePlugin is a template haskell error indicating that a core plugin being added has an invalid module due to being in the current package. Example(s): Test cases: -} TcRnAddInvalidCorePlugin :: !String -- ^ Module name -> TcRnMessage {-| TcRnAddDocToNonLocalDefn is a template haskell error for documentation being added to a definition which is not in the current module. Example(s): Test cases: showIface/should_fail/THPutDocExternal -} TcRnAddDocToNonLocalDefn :: !TH.DocLoc -> TcRnMessage {-| TcRnFailedToLookupThInstName is a template haskell error that occurrs when looking up an instance fails. Example(s): Test cases: showIface/should_fail/THPutDocNonExistent -} TcRnFailedToLookupThInstName :: !TH.Type -> !LookupTHInstNameErrReason -> TcRnMessage {-| TcRnCannotReifyInstance is a template haskell error for when an instance being reified via `reifyInstances` is not a class constraint or type family application. Example(s): Test cases: -} TcRnCannotReifyInstance :: !Type -> TcRnMessage {-| TcRnCannotReifyOutOfScopeThing is a template haskell error indicating that the given name is not in scope and therefore cannot be reified. Example(s): Test cases: th/T16976f -} TcRnCannotReifyOutOfScopeThing :: !TH.Name -> TcRnMessage {-| TcRnCannotReifyThingNotInTypeEnv is a template haskell error occurring when the given name is not in the type environment and therefore cannot be reified. Example(s): Test cases: -} TcRnCannotReifyThingNotInTypeEnv :: !Name -> TcRnMessage {-| TcRnNoRolesAssociatedWithName is a template haskell error for when the user tries to reify the roles of a given name but it is not something that has roles associated with it. Example(s): Test cases: -} TcRnNoRolesAssociatedWithThing :: !TcTyThing -> TcRnMessage {-| TcRnCannotRepresentThing is a template haskell error indicating that a type cannot be reified because it does not have a representation in template haskell. Example(s): Test cases: -} TcRnCannotRepresentType :: !UnrepresentableTypeDescr -> !Type -> TcRnMessage {-| TcRnRunSpliceFailure is an error indicating that a template haskell splice failed to be converted into a valid expression. Example(s): Test cases: th/T10828a th/T10828b th/T12478_4 th/T15270A th/T15270B th/T16895a th/T16895b th/T16895c th/T16895d th/T16895e th/T17379a th/T17379b th/T18740d th/T2597b th/T2674 th/T3395 th/T7484 th/T7667a th/TH_implicitParamsErr1 th/TH_implicitParamsErr2 th/TH_implicitParamsErr3 th/TH_invalid_add_top_decl -} TcRnRunSpliceFailure :: !(Maybe String) -- ^ Name of the function used to run the splice -> !RunSpliceFailReason -> TcRnMessage {-| TcRnUserErrReported is an error or warning thrown using 'qReport' from the 'Quasi' instance of 'TcM'. Example(s): Test cases: -} TcRnReportCustomQuasiError :: !Bool -- True => Error, False => Warning -> !String -- Error body -> TcRnMessage {-| TcRnInterfaceLookupError is an error resulting from looking up a name in an interface file. Example(s): Test cases: -} TcRnInterfaceLookupError :: !Name -> !SDoc -> TcRnMessage {- | TcRnUnsatisfiedMinimalDef is a warning that occurs when a class instance is missing methods that are required by the minimal definition. Example: class C a where foo :: a -> a instance C () -- | foo needs to be defined here Test cases: testsuite/tests/typecheck/prog001/typecheck.prog001 testsuite/tests/typecheck/should_compile/tc126 testsuite/tests/typecheck/should_compile/T7903 testsuite/tests/typecheck/should_compile/tc116 testsuite/tests/typecheck/should_compile/tc175 testsuite/tests/typecheck/should_compile/HasKey testsuite/tests/typecheck/should_compile/tc125 testsuite/tests/typecheck/should_compile/tc078 testsuite/tests/typecheck/should_compile/tc161 testsuite/tests/typecheck/should_fail/T5051 testsuite/tests/typecheck/should_compile/T21583 testsuite/tests/backpack/should_compile/bkp47 testsuite/tests/backpack/should_fail/bkpfail25 testsuite/tests/parser/should_compile/T2245 testsuite/tests/parser/should_compile/read014 testsuite/tests/indexed-types/should_compile/Class3 testsuite/tests/indexed-types/should_compile/Simple2 testsuite/tests/indexed-types/should_fail/T7862 testsuite/tests/deriving/should_compile/deriving-1935 testsuite/tests/deriving/should_compile/T9968a testsuite/tests/deriving/should_compile/drv003 testsuite/tests/deriving/should_compile/T4966 testsuite/tests/deriving/should_compile/T14094 testsuite/tests/perf/compiler/T15304 testsuite/tests/warnings/minimal/WarnMinimal testsuite/tests/simplCore/should_compile/simpl020 testsuite/tests/deSugar/should_compile/T14546d testsuite/tests/ghci/scripts/T5820 testsuite/tests/ghci/scripts/ghci019 -} TcRnUnsatisfiedMinimalDef :: ClassMinimalDef -> TcRnMessage {- | 'TcRnMisplacedInstSig' is an error that happens when a method in a class instance is given a type signature, but the user has not enabled the @InstanceSigs@ extension. Test case: testsuite/tests/module/mod45 -} TcRnMisplacedInstSig :: Name -> (LHsSigType GhcRn) -> TcRnMessage {- | 'TcRnBadBootFamInstDecl' is an error that is triggered by a type family instance being declared in an hs-boot file. Test case: testsuite/tests/indexed-types/should_fail/HsBootFam -} TcRnBadBootFamInstDecl :: {} -> TcRnMessage {- | 'TcRnIllegalFamilyInstance' is an error that occurs when an associated type or data family is given a top-level instance. Test case: testsuite/tests/indexed-types/should_fail/T3092 -} TcRnIllegalFamilyInstance :: TyCon -> TcRnMessage {- | 'TcRnMissingClassAssoc' is an error that occurs when a class instance for a class with an associated type or data family is missing a corresponding family instance declaration. Test case: testsuite/tests/indexed-types/should_fail/SimpleFail7 -} TcRnMissingClassAssoc :: TyCon -> TcRnMessage {- | 'TcRnBadFamInstDecl' is an error that is triggered by a type or data family instance without the @TypeFamilies@ extension. Test case: testsuite/tests/indexed-types/should_fail/BadFamInstDecl -} TcRnBadFamInstDecl :: TyCon -> TcRnMessage {- | 'TcRnNotOpenFamily' is an error that is triggered by attempting to give a top-level (open) type family instance for a closed type family. Test cases: testsuite/tests/indexed-types/should_fail/Overlap7 testsuite/tests/indexed-types/should_fail/Overlap3 -} TcRnNotOpenFamily :: TyCon -> TcRnMessage {-| TcRnNoRebindableSyntaxRecordDot is an error triggered by an overloaded record update without RebindableSyntax enabled. Example(s): Test cases: parser/should_fail/RecordDotSyntaxFail5 -} TcRnNoRebindableSyntaxRecordDot :: TcRnMessage {-| TcRnNoFieldPunsRecordDot is an error triggered by the use of record field puns in an overloaded record update without enabling NamedFieldPuns. Example(s): print $ a{ foo.bar.baz.quux } Test cases: parser/should_fail/RecordDotSyntaxFail12 -} TcRnNoFieldPunsRecordDot :: TcRnMessage {-| TcRnIllegalStaticExpression is an error thrown when user creates a static pointer via TemplateHaskell without enabling the StaticPointers extension. Example(s): Test cases: th/T14204 -} TcRnIllegalStaticExpression :: HsExpr GhcPs -> TcRnMessage {-| TcRnIllegalStaticFormInSplice is an error when a user attempts to define a static pointer in a Template Haskell splice. Example(s): Test cases: th/TH_StaticPointers02 -} TcRnIllegalStaticFormInSplice :: HsExpr GhcPs -> TcRnMessage {-| TcRnListComprehensionDuplicateBinding is an error triggered by duplicate let-bindings in a list comprehension. Example(s): [ () | let a = 13 | let a = 17 ] Test cases: typecheck/should_fail/tcfail092 -} TcRnListComprehensionDuplicateBinding :: Name -> TcRnMessage {-| TcRnEmptyStmtsGroup is an error triggered by an empty list of statements in a statement block. For more information, see 'EmptyStatementGroupErrReason' Example(s): [() | then ()] do proc () -> do Test cases: rename/should_fail/RnEmptyStatementGroup1 -} TcRnEmptyStmtsGroup:: EmptyStatementGroupErrReason -> TcRnMessage {-| TcRnLastStmtNotExpr is an error caused by the last statement in a statement block not being an expression. Example(s): do x <- pure () do let x = 5 Test cases: rename/should_fail/T6060 parser/should_fail/T3811g parser/should_fail/readFail028 -} TcRnLastStmtNotExpr :: HsStmtContext GhcRn -> UnexpectedStatement -> TcRnMessage {-| TcRnUnexpectedStatementInContext is an error when a statement appears in an unexpected context (e.g. an arrow statement appears in a list comprehension). Example(s): Test cases: parser/should_fail/readFail042 parser/should_fail/readFail038 parser/should_fail/readFail043 -} TcRnUnexpectedStatementInContext :: HsStmtContext GhcRn -> UnexpectedStatement -> Maybe LangExt.Extension -> TcRnMessage {-| TcRnIllegalTupleSection is an error triggered by usage of a tuple section without enabling the TupleSections extension. Example(s): (5,) Test cases: rename/should_fail/rnfail056 -} TcRnIllegalTupleSection :: TcRnMessage {-| TcRnIllegalImplicitParameterBindings is an error triggered by binding an implicit parameter in an mdo block. Example(s): mdo { let { ?x = 5 }; () } Test cases: rename/should_fail/RnImplicitBindInMdoNotation -} TcRnIllegalImplicitParameterBindings :: Either (HsLocalBindsLR GhcPs GhcPs) (HsLocalBindsLR GhcRn GhcPs) -> TcRnMessage {-| TcRnSectionWithoutParentheses is an error triggered by attempting to use an operator section without parentheses. Example(s): (`head` x, ()) Test cases: rename/should_fail/T2490 rename/should_fail/T5657 -} TcRnSectionWithoutParentheses :: HsExpr GhcPs -> TcRnMessage {-| TcRnLoopySuperclassSolve is a warning, controlled by @-Wloopy-superclass-solve@, that is triggered when GHC solves a constraint in a possibly-loopy way, violating the class instance termination rules described in the section "Undecidable instances and loopy superclasses" of the user's guide. Example: class Foo f class Foo f => Bar f g instance Bar f f => Bar f (h k) Test cases: T20666, T20666{a,b}, T22891, T22912. -} TcRnLoopySuperclassSolve :: CtLoc -- ^ Wanted 'CtLoc' -> PredType -- ^ Wanted 'PredType' -> TcRnMessage deriving (forall x. TcRnMessage -> Rep TcRnMessage x) -> (forall x. Rep TcRnMessage x -> TcRnMessage) -> Generic TcRnMessage forall x. Rep TcRnMessage x -> TcRnMessage forall x. TcRnMessage -> Rep TcRnMessage x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. TcRnMessage -> Rep TcRnMessage x from :: forall x. TcRnMessage -> Rep TcRnMessage x $cto :: forall x. Rep TcRnMessage x -> TcRnMessage to :: forall x. Rep TcRnMessage x -> TcRnMessage Generic -- | Things forbidden in @type data@ declarations. -- See Note [Type data declarations] data TypeDataForbids = TypeDataForbidsDatatypeContexts | TypeDataForbidsLabelledFields | TypeDataForbidsStrictnessAnnotations | TypeDataForbidsDerivingClauses deriving (forall x. TypeDataForbids -> Rep TypeDataForbids x) -> (forall x. Rep TypeDataForbids x -> TypeDataForbids) -> Generic TypeDataForbids forall x. Rep TypeDataForbids x -> TypeDataForbids forall x. TypeDataForbids -> Rep TypeDataForbids x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. TypeDataForbids -> Rep TypeDataForbids x from :: forall x. TypeDataForbids -> Rep TypeDataForbids x $cto :: forall x. Rep TypeDataForbids x -> TypeDataForbids to :: forall x. Rep TypeDataForbids x -> TypeDataForbids Generic instance Outputable TypeDataForbids where ppr :: TypeDataForbids -> SDoc ppr TypeDataForbids TypeDataForbidsDatatypeContexts = String -> SDoc forall doc. IsLine doc => String -> doc text String "Data type contexts" ppr TypeDataForbids TypeDataForbidsLabelledFields = String -> SDoc forall doc. IsLine doc => String -> doc text String "Labelled fields" ppr TypeDataForbids TypeDataForbidsStrictnessAnnotations = String -> SDoc forall doc. IsLine doc => String -> doc text String "Strictness flags" ppr TypeDataForbids TypeDataForbidsDerivingClauses = String -> SDoc forall doc. IsLine doc => String -> doc text String "Deriving clauses" data RunSpliceFailReason = ConversionFail !ThingBeingConverted !ConversionFailReason deriving (forall x. RunSpliceFailReason -> Rep RunSpliceFailReason x) -> (forall x. Rep RunSpliceFailReason x -> RunSpliceFailReason) -> Generic RunSpliceFailReason forall x. Rep RunSpliceFailReason x -> RunSpliceFailReason forall x. RunSpliceFailReason -> Rep RunSpliceFailReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. RunSpliceFailReason -> Rep RunSpliceFailReason x from :: forall x. RunSpliceFailReason -> Rep RunSpliceFailReason x $cto :: forall x. Rep RunSpliceFailReason x -> RunSpliceFailReason to :: forall x. Rep RunSpliceFailReason x -> RunSpliceFailReason Generic -- | Identifies the TH splice attempting to be converted data ThingBeingConverted = ConvDec !TH.Dec | ConvExp !TH.Exp | ConvPat !TH.Pat | ConvType !TH.Type -- | The reason a TH splice could not be converted to a Haskell expression data ConversionFailReason = IllegalOccName !OccName.NameSpace !String | SumAltArityExceeded !TH.SumAlt !TH.SumArity | IllegalSumAlt !TH.SumAlt | IllegalSumArity !TH.SumArity | MalformedType !TypeOrKind !TH.Type | IllegalLastStatement !HsDoFlavour !(LStmt GhcPs (LHsExpr GhcPs)) | KindSigsOnlyAllowedOnGADTs | IllegalDeclaration !THDeclDescriptor !IllegalDecls | CannotMixGADTConsWith98Cons | EmptyStmtListInDoBlock | NonVarInInfixExpr | MultiWayIfWithoutAlts | CasesExprWithoutAlts | ImplicitParamsWithOtherBinds | InvalidCCallImpent !String -- ^ Source | RecGadtNoCons | GadtNoCons | InvalidTypeInstanceHeader !TH.Type | InvalidTyFamInstLHS !TH.Type | InvalidImplicitParamBinding | DefaultDataInstDecl ![LDataFamInstDecl GhcPs] | FunBindLacksEquations !TH.Name deriving (forall x. ConversionFailReason -> Rep ConversionFailReason x) -> (forall x. Rep ConversionFailReason x -> ConversionFailReason) -> Generic ConversionFailReason forall x. Rep ConversionFailReason x -> ConversionFailReason forall x. ConversionFailReason -> Rep ConversionFailReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. ConversionFailReason -> Rep ConversionFailReason x from :: forall x. ConversionFailReason -> Rep ConversionFailReason x $cto :: forall x. Rep ConversionFailReason x -> ConversionFailReason to :: forall x. Rep ConversionFailReason x -> ConversionFailReason Generic data IllegalDecls = IllegalDecls !(NE.NonEmpty (LHsDecl GhcPs)) | IllegalFamDecls !(NE.NonEmpty (LFamilyDecl GhcPs)) -- | Label for a TH declaration data THDeclDescriptor = InstanceDecl | WhereClause | LetBinding | LetExpression | ClssDecl -- | Specifies which back ends can handle a requested foreign import or export type ExpectedBackends = [Backend] -- | Specifies which calling convention is unsupported on the current platform data UnsupportedCallConvention = StdCallConvUnsupported | PrimCallConvUnsupported | JavaScriptCallConvUnsupported deriving UnsupportedCallConvention -> UnsupportedCallConvention -> Bool (UnsupportedCallConvention -> UnsupportedCallConvention -> Bool) -> (UnsupportedCallConvention -> UnsupportedCallConvention -> Bool) -> Eq UnsupportedCallConvention forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: UnsupportedCallConvention -> UnsupportedCallConvention -> Bool == :: UnsupportedCallConvention -> UnsupportedCallConvention -> Bool $c/= :: UnsupportedCallConvention -> UnsupportedCallConvention -> Bool /= :: UnsupportedCallConvention -> UnsupportedCallConvention -> Bool Eq -- | Whether the error pertains to a function argument or a result. data ArgOrResult = Arg | Result -- | Which parts of a record field are affected by a particular error or warning. data RecordFieldPart = RecordFieldConstructor !Name | RecordFieldPattern !Name | RecordFieldUpdate -- | Where a shadowed name comes from data ShadowedNameProvenance = ShadowedNameProvenanceLocal !SrcLoc -- ^ The shadowed name is local to the module | ShadowedNameProvenanceGlobal [GlobalRdrElt] -- ^ The shadowed name is global, typically imported from elsewhere. -- | In what context did we require a type to have a fixed runtime representation? -- -- Used by 'GHC.Tc.Utils.TcMType.checkTypeHasFixedRuntimeRep' for throwing -- representation polymorphism errors when validity checking. -- -- See Note [Representation polymorphism checking] in GHC.Tc.Utils.Concrete data FixedRuntimeRepProvenance -- | Data constructor fields must have a fixed runtime representation. -- -- Tests: T11734, T18534. = FixedRuntimeRepDataConField -- | Pattern synonym signature arguments must have a fixed runtime representation. -- -- Test: RepPolyPatSynArg. | FixedRuntimeRepPatSynSigArg -- | Pattern synonym signature scrutinee must have a fixed runtime representation. -- -- Test: RepPolyPatSynRes. | FixedRuntimeRepPatSynSigRes pprFixedRuntimeRepProvenance :: FixedRuntimeRepProvenance -> SDoc pprFixedRuntimeRepProvenance :: FixedRuntimeRepProvenance -> SDoc pprFixedRuntimeRepProvenance FixedRuntimeRepProvenance FixedRuntimeRepDataConField = String -> SDoc forall doc. IsLine doc => String -> doc text String "data constructor field" pprFixedRuntimeRepProvenance FixedRuntimeRepProvenance FixedRuntimeRepPatSynSigArg = String -> SDoc forall doc. IsLine doc => String -> doc text String "pattern synonym argument" pprFixedRuntimeRepProvenance FixedRuntimeRepProvenance FixedRuntimeRepPatSynSigRes = String -> SDoc forall doc. IsLine doc => String -> doc text String "pattern synonym scrutinee" -- | Why the particular illegal newtype error arose together with more -- information, if any. data IllegalNewtypeReason = DoesNotHaveSingleField !Int | IsNonLinear | IsGADT | HasConstructorContext | HasExistentialTyVar | HasStrictnessAnnotation deriving (forall x. IllegalNewtypeReason -> Rep IllegalNewtypeReason x) -> (forall x. Rep IllegalNewtypeReason x -> IllegalNewtypeReason) -> Generic IllegalNewtypeReason forall x. Rep IllegalNewtypeReason x -> IllegalNewtypeReason forall x. IllegalNewtypeReason -> Rep IllegalNewtypeReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. IllegalNewtypeReason -> Rep IllegalNewtypeReason x from :: forall x. IllegalNewtypeReason -> Rep IllegalNewtypeReason x $cto :: forall x. Rep IllegalNewtypeReason x -> IllegalNewtypeReason to :: forall x. Rep IllegalNewtypeReason x -> IllegalNewtypeReason Generic -- | Why the particular injectivity error arose together with more information, -- if any. data InjectivityErrReason = InjErrRhsBareTyVar [Type] | InjErrRhsCannotBeATypeFam | InjErrRhsOverlap | InjErrCannotInferFromRhs !TyVarSet !HasKinds !SuggestUndecidableInstances data HasKinds = YesHasKinds | NoHasKinds deriving (Int -> HasKinds -> ShowS [HasKinds] -> ShowS HasKinds -> String (Int -> HasKinds -> ShowS) -> (HasKinds -> String) -> ([HasKinds] -> ShowS) -> Show HasKinds forall a. (Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a $cshowsPrec :: Int -> HasKinds -> ShowS showsPrec :: Int -> HasKinds -> ShowS $cshow :: HasKinds -> String show :: HasKinds -> String $cshowList :: [HasKinds] -> ShowS showList :: [HasKinds] -> ShowS Show, HasKinds -> HasKinds -> Bool (HasKinds -> HasKinds -> Bool) -> (HasKinds -> HasKinds -> Bool) -> Eq HasKinds forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: HasKinds -> HasKinds -> Bool == :: HasKinds -> HasKinds -> Bool $c/= :: HasKinds -> HasKinds -> Bool /= :: HasKinds -> HasKinds -> Bool Eq) hasKinds :: Bool -> HasKinds hasKinds :: Bool -> HasKinds hasKinds Bool True = HasKinds YesHasKinds hasKinds Bool False = HasKinds NoHasKinds data SuggestUndecidableInstances = YesSuggestUndecidableInstaces | NoSuggestUndecidableInstaces deriving (Int -> SuggestUndecidableInstances -> ShowS [SuggestUndecidableInstances] -> ShowS SuggestUndecidableInstances -> String (Int -> SuggestUndecidableInstances -> ShowS) -> (SuggestUndecidableInstances -> String) -> ([SuggestUndecidableInstances] -> ShowS) -> Show SuggestUndecidableInstances forall a. (Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a $cshowsPrec :: Int -> SuggestUndecidableInstances -> ShowS showsPrec :: Int -> SuggestUndecidableInstances -> ShowS $cshow :: SuggestUndecidableInstances -> String show :: SuggestUndecidableInstances -> String $cshowList :: [SuggestUndecidableInstances] -> ShowS showList :: [SuggestUndecidableInstances] -> ShowS Show, SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool (SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool) -> (SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool) -> Eq SuggestUndecidableInstances forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool == :: SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool $c/= :: SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool /= :: SuggestUndecidableInstances -> SuggestUndecidableInstances -> Bool Eq) suggestUndecidableInstances :: Bool -> SuggestUndecidableInstances suggestUndecidableInstances :: Bool -> SuggestUndecidableInstances suggestUndecidableInstances Bool True = SuggestUndecidableInstances YesSuggestUndecidableInstaces suggestUndecidableInstances Bool False = SuggestUndecidableInstances NoSuggestUndecidableInstaces data SuggestUnliftedTypes = SuggestUnliftedNewtypes | SuggestUnliftedDatatypes -- | A description of whether something is a -- -- * @data@ or @newtype@ ('DataDeclSort') -- -- * @data instance@ or @newtype instance@ ('DataInstanceSort') -- -- * @data family@ ('DataFamilySort') -- -- At present, this data type is only consumed by 'checkDataKindSig'. data DataSort = DataDeclSort NewOrData | DataInstanceSort NewOrData | DataFamilySort ppDataSort :: DataSort -> SDoc ppDataSort :: DataSort -> SDoc ppDataSort DataSort data_sort = String -> SDoc forall doc. IsLine doc => String -> doc text (String -> SDoc) -> String -> SDoc forall a b. (a -> b) -> a -> b $ case DataSort data_sort of DataDeclSort NewOrData DataType -> String "Data type" DataDeclSort NewOrData NewType -> String "Newtype" DataInstanceSort NewOrData DataType -> String "Data instance" DataInstanceSort NewOrData NewType -> String "Newtype instance" DataSort DataFamilySort -> String "Data family" -- | Helper type used in 'checkDataKindSig'. -- -- Superficially similar to 'ContextKind', but it lacks 'AnyKind' -- and 'AnyBoxedKind', and instead of @'TheKind' liftedTypeKind@ -- provides 'LiftedKind', which is much simpler to match on and -- handle in 'isAllowedDataResKind'. data AllowedDataResKind = AnyTYPEKind | AnyBoxedKind | LiftedKind -- | A data type to describe why a variable is not closed. -- See Note [Not-closed error messages] in GHC.Tc.Gen.Expr data NotClosedReason = NotLetBoundReason | NotTypeClosed VarSet | NotClosed Name NotClosedReason data SuggestPartialTypeSignatures = YesSuggestPartialTypeSignatures | NoSuggestPartialTypeSignatures deriving (Int -> SuggestPartialTypeSignatures -> ShowS [SuggestPartialTypeSignatures] -> ShowS SuggestPartialTypeSignatures -> String (Int -> SuggestPartialTypeSignatures -> ShowS) -> (SuggestPartialTypeSignatures -> String) -> ([SuggestPartialTypeSignatures] -> ShowS) -> Show SuggestPartialTypeSignatures forall a. (Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a $cshowsPrec :: Int -> SuggestPartialTypeSignatures -> ShowS showsPrec :: Int -> SuggestPartialTypeSignatures -> ShowS $cshow :: SuggestPartialTypeSignatures -> String show :: SuggestPartialTypeSignatures -> String $cshowList :: [SuggestPartialTypeSignatures] -> ShowS showList :: [SuggestPartialTypeSignatures] -> ShowS Show, SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool (SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool) -> (SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool) -> Eq SuggestPartialTypeSignatures forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool == :: SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool $c/= :: SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool /= :: SuggestPartialTypeSignatures -> SuggestPartialTypeSignatures -> Bool Eq) suggestPartialTypeSignatures :: Bool -> SuggestPartialTypeSignatures suggestPartialTypeSignatures :: Bool -> SuggestPartialTypeSignatures suggestPartialTypeSignatures Bool True = SuggestPartialTypeSignatures YesSuggestPartialTypeSignatures suggestPartialTypeSignatures Bool False = SuggestPartialTypeSignatures NoSuggestPartialTypeSignatures data UsingGeneralizedNewtypeDeriving = YesGeneralizedNewtypeDeriving | NoGeneralizedNewtypeDeriving deriving UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool (UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool) -> (UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool) -> Eq UsingGeneralizedNewtypeDeriving forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool == :: UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool $c/= :: UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool /= :: UsingGeneralizedNewtypeDeriving -> UsingGeneralizedNewtypeDeriving -> Bool Eq usingGeneralizedNewtypeDeriving :: Bool -> UsingGeneralizedNewtypeDeriving usingGeneralizedNewtypeDeriving :: Bool -> UsingGeneralizedNewtypeDeriving usingGeneralizedNewtypeDeriving Bool True = UsingGeneralizedNewtypeDeriving YesGeneralizedNewtypeDeriving usingGeneralizedNewtypeDeriving Bool False = UsingGeneralizedNewtypeDeriving NoGeneralizedNewtypeDeriving data DeriveAnyClassEnabled = YesDeriveAnyClassEnabled | NoDeriveAnyClassEnabled deriving DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool (DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool) -> (DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool) -> Eq DeriveAnyClassEnabled forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool == :: DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool $c/= :: DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool /= :: DeriveAnyClassEnabled -> DeriveAnyClassEnabled -> Bool Eq deriveAnyClassEnabled :: Bool -> DeriveAnyClassEnabled deriveAnyClassEnabled :: Bool -> DeriveAnyClassEnabled deriveAnyClassEnabled Bool True = DeriveAnyClassEnabled YesDeriveAnyClassEnabled deriveAnyClassEnabled Bool False = DeriveAnyClassEnabled NoDeriveAnyClassEnabled -- | Why a particular typeclass instance couldn't be derived. data DeriveInstanceErrReason = -- | The typeclass instance is not well-kinded. DerivErrNotWellKinded !TyCon -- ^ The type constructor that occurs in -- the typeclass instance declaration. !Kind -- ^ The typeclass kind. !Int -- ^ The number of typeclass arguments that GHC -- kept. See Note [tc_args and tycon arity] in -- GHC.Tc.Deriv. -- | Generic instances can only be derived using the stock strategy -- in Safe Haskell. | DerivErrSafeHaskellGenericInst | DerivErrDerivingViaWrongKind !Kind !Type !Kind | DerivErrNoEtaReduce !Type -- ^ The instance type -- | We cannot derive instances in boot files | DerivErrBootFileFound | DerivErrDataConsNotAllInScope !TyCon -- | We cannot use GND on non-newtype types | DerivErrGNDUsedOnData -- | We cannot derive instances of nullary classes | DerivErrNullaryClasses -- | Last arg must be newtype or data application | DerivErrLastArgMustBeApp | DerivErrNoFamilyInstance !TyCon [Type] | DerivErrNotStockDeriveable !DeriveAnyClassEnabled | DerivErrHasAssociatedDatatypes !HasAssociatedDataFamInsts !AssociatedTyLastVarInKind !AssociatedTyNotParamOverLastTyVar | DerivErrNewtypeNonDeriveableClass | DerivErrCannotEtaReduceEnough !Bool -- Is eta-reduction OK? | DerivErrOnlyAnyClassDeriveable !TyCon -- ^ Type constructor for which the instance -- is requested !DeriveAnyClassEnabled -- ^ Whether or not -XDeriveAnyClass is enabled -- already. -- | Stock deriving won't work, but perhaps DeriveAnyClass will. | DerivErrNotDeriveable !DeriveAnyClassEnabled -- | The given 'PredType' is not a class. | DerivErrNotAClass !PredType -- | The given (representation of the) 'TyCon' has no -- data constructors. | DerivErrNoConstructors !TyCon | DerivErrLangExtRequired !LangExt.Extension -- | GHC simply doesn't how to how derive the input 'Class' for the given -- 'Type'. | DerivErrDunnoHowToDeriveForType !Type -- | The given 'TyCon' must be an enumeration. -- See Note [Enumeration types] in GHC.Core.TyCon | DerivErrMustBeEnumType !TyCon -- | The given 'TyCon' must have /precisely/ one constructor. | DerivErrMustHaveExactlyOneConstructor !TyCon -- | The given data type must have some parameters. | DerivErrMustHaveSomeParameters !TyCon -- | The given data type must not have a class context. | DerivErrMustNotHaveClassContext !TyCon !ThetaType -- | We couldn't derive an instance for a particular data constructor -- for a variety of reasons. | DerivErrBadConstructor !(Maybe HasWildcard) [DeriveInstanceBadConstructor] -- | We couldn't derive a 'Generic' instance for the given type for a -- variety of reasons | DerivErrGenerics [DeriveGenericsErrReason] -- | We couldn't derive an instance either because the type was not an -- enum type or because it did have more than one constructor. | DerivErrEnumOrProduct !DeriveInstanceErrReason !DeriveInstanceErrReason deriving (forall x. DeriveInstanceErrReason -> Rep DeriveInstanceErrReason x) -> (forall x. Rep DeriveInstanceErrReason x -> DeriveInstanceErrReason) -> Generic DeriveInstanceErrReason forall x. Rep DeriveInstanceErrReason x -> DeriveInstanceErrReason forall x. DeriveInstanceErrReason -> Rep DeriveInstanceErrReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. DeriveInstanceErrReason -> Rep DeriveInstanceErrReason x from :: forall x. DeriveInstanceErrReason -> Rep DeriveInstanceErrReason x $cto :: forall x. Rep DeriveInstanceErrReason x -> DeriveInstanceErrReason to :: forall x. Rep DeriveInstanceErrReason x -> DeriveInstanceErrReason Generic data DeriveInstanceBadConstructor = -- | The given 'DataCon' must be truly polymorphic in the -- last argument of the data type. DerivErrBadConExistential !DataCon -- | The given 'DataCon' must not use the type variable in a function argument" | DerivErrBadConCovariant !DataCon -- | The given 'DataCon' must not contain function types | DerivErrBadConFunTypes !DataCon -- | The given 'DataCon' must use the type variable only -- as the last argument of a data type | DerivErrBadConWrongArg !DataCon -- | The given 'DataCon' is a GADT so we cannot directly -- derive an istance for it. | DerivErrBadConIsGADT !DataCon -- | The given 'DataCon' has existentials type vars in its type. | DerivErrBadConHasExistentials !DataCon -- | The given 'DataCon' has constraints in its type. | DerivErrBadConHasConstraints !DataCon -- | The given 'DataCon' has a higher-rank type. | DerivErrBadConHasHigherRankType !DataCon data DeriveGenericsErrReason = -- | The type must not have some datatype context. DerivErrGenericsMustNotHaveDatatypeContext !TyCon -- | The data constructor must not have exotic unlifted -- or polymorphic arguments. | DerivErrGenericsMustNotHaveExoticArgs !DataCon -- | The data constructor must be a vanilla constructor. | DerivErrGenericsMustBeVanillaDataCon !DataCon -- | The type must have some type parameters. -- check (d) from Note [Requirements for deriving Generic and Rep] -- in GHC.Tc.Deriv.Generics. | DerivErrGenericsMustHaveSomeTypeParams !TyCon -- | The data constructor must not have existential arguments. | DerivErrGenericsMustNotHaveExistentials !DataCon -- | The derivation applies a type to an argument involving -- the last parameter but the applied type is not of kind * -> *. | DerivErrGenericsWrongArgKind !DataCon data HasWildcard = YesHasWildcard | NoHasWildcard deriving HasWildcard -> HasWildcard -> Bool (HasWildcard -> HasWildcard -> Bool) -> (HasWildcard -> HasWildcard -> Bool) -> Eq HasWildcard forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: HasWildcard -> HasWildcard -> Bool == :: HasWildcard -> HasWildcard -> Bool $c/= :: HasWildcard -> HasWildcard -> Bool /= :: HasWildcard -> HasWildcard -> Bool Eq hasWildcard :: Bool -> HasWildcard hasWildcard :: Bool -> HasWildcard hasWildcard Bool True = HasWildcard YesHasWildcard hasWildcard Bool False = HasWildcard NoHasWildcard -- | A context in which we don't allow anonymous wildcards. data BadAnonWildcardContext = WildcardNotLastInConstraint | ExtraConstraintWildcardNotAllowed SoleExtraConstraintWildcardAllowed | WildcardsNotAllowedAtAll -- | Whether a sole extra-constraint wildcard is allowed, -- e.g. @_ => ..@ as opposed to @( .., _ ) => ..@. data SoleExtraConstraintWildcardAllowed = SoleExtraConstraintWildcardNotAllowed | SoleExtraConstraintWildcardAllowed -- | A type representing whether or not the input type has associated data family instances. data HasAssociatedDataFamInsts = YesHasAdfs | NoHasAdfs deriving HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool (HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool) -> (HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool) -> Eq HasAssociatedDataFamInsts forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool == :: HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool $c/= :: HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool /= :: HasAssociatedDataFamInsts -> HasAssociatedDataFamInsts -> Bool Eq hasAssociatedDataFamInsts :: Bool -> HasAssociatedDataFamInsts hasAssociatedDataFamInsts :: Bool -> HasAssociatedDataFamInsts hasAssociatedDataFamInsts Bool True = HasAssociatedDataFamInsts YesHasAdfs hasAssociatedDataFamInsts Bool False = HasAssociatedDataFamInsts NoHasAdfs -- | If 'YesAssocTyLastVarInKind', the associated type of a typeclass -- contains the last type variable of the class in a kind, which is not (yet) allowed -- by GHC. data AssociatedTyLastVarInKind = YesAssocTyLastVarInKind !TyCon -- ^ The associated type family of the class | NoAssocTyLastVarInKind deriving AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool (AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool) -> (AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool) -> Eq AssociatedTyLastVarInKind forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool == :: AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool $c/= :: AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool /= :: AssociatedTyLastVarInKind -> AssociatedTyLastVarInKind -> Bool Eq associatedTyLastVarInKind :: Maybe TyCon -> AssociatedTyLastVarInKind associatedTyLastVarInKind :: Maybe TyCon -> AssociatedTyLastVarInKind associatedTyLastVarInKind (Just TyCon tc) = TyCon -> AssociatedTyLastVarInKind YesAssocTyLastVarInKind TyCon tc associatedTyLastVarInKind Maybe TyCon Nothing = AssociatedTyLastVarInKind NoAssocTyLastVarInKind -- | If 'NoAssociatedTyNotParamOverLastTyVar', the associated type of a -- typeclass is not parameterized over the last type variable of the class data AssociatedTyNotParamOverLastTyVar = YesAssociatedTyNotParamOverLastTyVar !TyCon -- ^ The associated type family of the class | NoAssociatedTyNotParamOverLastTyVar deriving AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool (AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool) -> (AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool) -> Eq AssociatedTyNotParamOverLastTyVar forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a $c== :: AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool == :: AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool $c/= :: AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool /= :: AssociatedTyNotParamOverLastTyVar -> AssociatedTyNotParamOverLastTyVar -> Bool Eq associatedTyNotParamOverLastTyVar :: Maybe TyCon -> AssociatedTyNotParamOverLastTyVar associatedTyNotParamOverLastTyVar :: Maybe TyCon -> AssociatedTyNotParamOverLastTyVar associatedTyNotParamOverLastTyVar (Just TyCon tc) = TyCon -> AssociatedTyNotParamOverLastTyVar YesAssociatedTyNotParamOverLastTyVar TyCon tc associatedTyNotParamOverLastTyVar Maybe TyCon Nothing = AssociatedTyNotParamOverLastTyVar NoAssociatedTyNotParamOverLastTyVar -- | What kind of thing is missing a type signature? -- -- Used for reporting @"missing signature"@ warnings, see -- 'tcRnMissingSignature'. data MissingSignature = MissingTopLevelBindingSig Name Type | MissingPatSynSig PatSyn | MissingTyConKindSig TyCon Bool -- ^ whether -XCUSKs is enabled -- | Is the object we are dealing with exported or not? -- -- Used for reporting @"missing signature"@ warnings, see -- 'TcRnMissingSignature'. data Exported = IsNotExported | IsExported instance Outputable Exported where ppr :: Exported -> SDoc ppr Exported IsNotExported = String -> SDoc forall doc. IsLine doc => String -> doc text String "IsNotExported" ppr Exported IsExported = String -> SDoc forall doc. IsLine doc => String -> doc text String "IsExported" -------------------------------------------------------------------------------- -- -- Errors used in GHC.Tc.Errors -- -------------------------------------------------------------------------------- {- Note [Error report] ~~~~~~~~~~~~~~~~~~~~~~ The idea is that error msgs are divided into three parts: the main msg, the context block ("In the second argument of ..."), and the relevant bindings block, which are displayed in that order, with a mark to divide them. The the main msg ('report_important') varies depending on the error in question, but context and relevant bindings are always the same, which should simplify visual parsing. See 'GHC.Tc.Errors.Types.SolverReport' and 'GHC.Tc.Errors.mkErrorReport'. -} -- | A collection of main error messages and supplementary information. -- -- In practice, we will: -- - display the important messages first, -- - then the error context (e.g. by way of a call to 'GHC.Tc.Errors.mkErrorReport'), -- - then the supplementary information (e.g. relevant bindings, valid hole fits), -- - then the hints ("Possible fix: ..."). -- -- So this is mostly just a way of making sure that the error context appears -- early on rather than at the end of the message. -- -- See Note [Error report] for details. data SolverReport = SolverReport { SolverReport -> SolverReportWithCtxt sr_important_msg :: SolverReportWithCtxt , SolverReport -> [SolverReportSupplementary] sr_supplementary :: [SolverReportSupplementary] , SolverReport -> [GhcHint] sr_hints :: [GhcHint] } -- | Additional information to print in a 'SolverReport', after the -- important messages and after the error context. -- -- See Note [Error report]. data SolverReportSupplementary = SupplementaryBindings RelevantBindings | SupplementaryHoleFits ValidHoleFits | SupplementaryCts [(PredType, RealSrcSpan)] -- | A 'TcSolverReportMsg', together with context (e.g. enclosing implication constraints) -- that are needed in order to report it. data SolverReportWithCtxt = SolverReportWithCtxt { SolverReportWithCtxt -> SolverReportErrCtxt reportContext :: SolverReportErrCtxt -- ^ Context for what we wish to report. -- This can change as we enter implications, so is -- stored alongside the content. , SolverReportWithCtxt -> TcSolverReportMsg reportContent :: TcSolverReportMsg -- ^ The content of the message to report. } deriving (forall x. SolverReportWithCtxt -> Rep SolverReportWithCtxt x) -> (forall x. Rep SolverReportWithCtxt x -> SolverReportWithCtxt) -> Generic SolverReportWithCtxt forall x. Rep SolverReportWithCtxt x -> SolverReportWithCtxt forall x. SolverReportWithCtxt -> Rep SolverReportWithCtxt x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. SolverReportWithCtxt -> Rep SolverReportWithCtxt x from :: forall x. SolverReportWithCtxt -> Rep SolverReportWithCtxt x $cto :: forall x. Rep SolverReportWithCtxt x -> SolverReportWithCtxt to :: forall x. Rep SolverReportWithCtxt x -> SolverReportWithCtxt Generic -- | Context needed when reporting a 'TcSolverReportMsg', such as -- the enclosing implication constraints or whether we are deferring type errors. data SolverReportErrCtxt = CEC { SolverReportErrCtxt -> [Implication] cec_encl :: [Implication] -- ^ Enclosing implications -- (innermost first) -- ic_skols and givens are tidied, rest are not , SolverReportErrCtxt -> TidyEnv cec_tidy :: TidyEnv , SolverReportErrCtxt -> EvBindsVar cec_binds :: EvBindsVar -- ^ We make some errors (depending on cec_defer) -- into warnings, and emit evidence bindings -- into 'cec_binds' for unsolved constraints , SolverReportErrCtxt -> DiagnosticReason cec_defer_type_errors :: DiagnosticReason -- ^ Whether to defer type errors until runtime -- We might throw a warning on an error when encountering a hole, -- depending on the type of hole (expression hole, type hole, out of scope hole). -- We store the reasons for reporting a diagnostic for each type of hole. , SolverReportErrCtxt -> DiagnosticReason cec_expr_holes :: DiagnosticReason -- ^ Reason for reporting holes in expressions. , SolverReportErrCtxt -> DiagnosticReason cec_type_holes :: DiagnosticReason -- ^ Reason for reporting holes in types. , SolverReportErrCtxt -> DiagnosticReason cec_out_of_scope_holes :: DiagnosticReason -- ^ Reason for reporting out of scope holes. , SolverReportErrCtxt -> Bool cec_warn_redundant :: Bool -- ^ True <=> -Wredundant-constraints , SolverReportErrCtxt -> Bool cec_expand_syns :: Bool -- ^ True <=> -fprint-expanded-synonyms , SolverReportErrCtxt -> Bool cec_suppress :: Bool -- ^ True <=> More important errors have occurred, -- so create bindings if need be, but -- don't issue any more errors/warnings -- See Note [Suppressing error messages] } getUserGivens :: SolverReportErrCtxt -> [UserGiven] -- One item for each enclosing implication getUserGivens :: SolverReportErrCtxt -> [Implication] getUserGivens (CEC {cec_encl :: SolverReportErrCtxt -> [Implication] cec_encl = [Implication] implics}) = [Implication] -> [Implication] getUserGivensFromImplics [Implication] implics ---------------------------------------------------------------------------- -- -- ErrorItem -- ---------------------------------------------------------------------------- -- | A predicate with its arising location; used to encapsulate a constraint -- that will give rise to a diagnostic. data ErrorItem -- We could perhaps use Ct here (and indeed used to do exactly that), but -- having a separate type gives to denote errors-in-formation gives us -- a nice place to do pre-processing, such as calculating ei_suppress. -- Perhaps some day, an ErrorItem could eventually evolve to contain -- the error text (or some representation of it), so we can then have all -- the errors together when deciding which to report. = EI { ErrorItem -> Type ei_pred :: PredType -- report about this -- The ei_pred field will never be an unboxed equality with -- a (casted) tyvar on the right; this is guaranteed by the solver , ErrorItem -> Maybe TcEvDest ei_evdest :: Maybe TcEvDest -- for Wanteds, where to put evidence , ErrorItem -> CtFlavour ei_flavour :: CtFlavour , ErrorItem -> CtLoc ei_loc :: CtLoc , ErrorItem -> Maybe CtIrredReason ei_m_reason :: Maybe CtIrredReason -- if this ErrorItem was made from a -- CtIrred, this stores the reason , ErrorItem -> Bool ei_suppress :: Bool -- Suppress because of Note [Wanteds rewrite Wanteds] -- in GHC.Tc.Constraint } instance Outputable ErrorItem where ppr :: ErrorItem -> SDoc ppr (EI { ei_pred :: ErrorItem -> Type ei_pred = Type pred , ei_evdest :: ErrorItem -> Maybe TcEvDest ei_evdest = Maybe TcEvDest m_evdest , ei_flavour :: ErrorItem -> CtFlavour ei_flavour = CtFlavour flav , ei_suppress :: ErrorItem -> Bool ei_suppress = Bool supp }) = SDoc pp_supp SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> CtFlavour -> SDoc forall a. Outputable a => a -> SDoc ppr CtFlavour flav SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> Maybe TcEvDest -> SDoc forall {a}. Outputable a => Maybe a -> SDoc pp_dest Maybe TcEvDest m_evdest SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> Type -> SDoc forall a. Outputable a => a -> SDoc ppr Type pred where pp_dest :: Maybe a -> SDoc pp_dest Maybe a Nothing = SDoc forall doc. IsOutput doc => doc empty pp_dest (Just a ev) = a -> SDoc forall a. Outputable a => a -> SDoc ppr a ev SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> SDoc dcolon pp_supp :: SDoc pp_supp = if Bool supp then String -> SDoc forall doc. IsLine doc => String -> doc text String "suppress:" else SDoc forall doc. IsOutput doc => doc empty errorItemOrigin :: ErrorItem -> CtOrigin errorItemOrigin :: ErrorItem -> CtOrigin errorItemOrigin = CtLoc -> CtOrigin ctLocOrigin (CtLoc -> CtOrigin) -> (ErrorItem -> CtLoc) -> ErrorItem -> CtOrigin forall b c a. (b -> c) -> (a -> b) -> a -> c . ErrorItem -> CtLoc ei_loc errorItemEqRel :: ErrorItem -> EqRel errorItemEqRel :: ErrorItem -> EqRel errorItemEqRel = Type -> EqRel predTypeEqRel (Type -> EqRel) -> (ErrorItem -> Type) -> ErrorItem -> EqRel forall b c a. (b -> c) -> (a -> b) -> a -> c . ErrorItem -> Type ei_pred errorItemCtLoc :: ErrorItem -> CtLoc errorItemCtLoc :: ErrorItem -> CtLoc errorItemCtLoc = ErrorItem -> CtLoc ei_loc errorItemPred :: ErrorItem -> PredType errorItemPred :: ErrorItem -> Type errorItemPred = ErrorItem -> Type ei_pred {- Note [discardProvCtxtGivens] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In most situations we call all enclosing implications "useful". There is one exception, and that is when the constraint that causes the error is from the "provided" context of a pattern synonym declaration: pattern Pat :: (Num a, Eq a) => Show a => a -> Maybe a -- required => provided => type pattern Pat x <- (Just x, 4) When checking the pattern RHS we must check that it does actually bind all the claimed "provided" constraints; in this case, does the pattern (Just x, 4) bind the (Show a) constraint. Answer: no! But the implication we generate for this will look like forall a. (Num a, Eq a) => [W] Show a because when checking the pattern we must make the required constraints available, since they are needed to match the pattern (in this case the literal '4' needs (Num a, Eq a)). BUT we don't want to suggest adding (Show a) to the "required" constraints of the pattern synonym, thus: pattern Pat :: (Num a, Eq a, Show a) => Show a => a -> Maybe a It would then typecheck but it's silly. We want the /pattern/ to bind the alleged "provided" constraints, Show a. So we suppress that Implication in discardProvCtxtGivens. It's painfully ad-hoc but the truth is that adding it to the "required" constraints would work. Suppressing it solves two problems. First, we never tell the user that we could not deduce a "provided" constraint from the "required" context. Second, we never give a possible fix that suggests to add a "provided" constraint to the "required" context. For example, without this distinction the above code gives a bad error message (showing both problems): error: Could not deduce (Show a) ... from the context: (Eq a) ... Possible fix: add (Show a) to the context of the signature for pattern synonym `Pat' ... -} discardProvCtxtGivens :: CtOrigin -> [UserGiven] -> [UserGiven] discardProvCtxtGivens :: CtOrigin -> [Implication] -> [Implication] discardProvCtxtGivens CtOrigin orig [Implication] givens -- See Note [discardProvCtxtGivens] | ProvCtxtOrigin (PSB {psb_id :: forall idL idR. PatSynBind idL idR -> LIdP idL psb_id = L SrcSpanAnnN _ Name name}) <- CtOrigin orig = (Implication -> Bool) -> [Implication] -> [Implication] forall a. (a -> Bool) -> [a] -> [a] filterOut (Name -> Implication -> Bool discard Name name) [Implication] givens | Bool otherwise = [Implication] givens where discard :: Name -> Implication -> Bool discard Name n (Implic { ic_info :: Implication -> SkolemInfoAnon ic_info = SigSkol (PatSynCtxt Name n') Type _ [(Name, TcTyVar)] _ }) = Name n Name -> Name -> Bool forall a. Eq a => a -> a -> Bool == Name n' discard Name _ Implication _ = Bool False -- | An error reported after constraint solving. -- This is usually, some sort of unsolved constraint error, -- but we try to be specific about the precise problem we encountered. data TcSolverReportMsg -- | Quantified variables appear out of dependency order. -- -- Example: -- -- forall (a :: k) k. ... -- -- Test cases: BadTelescope2, T16418, T16247, T16726, T18451. = BadTelescope TyVarBndrs [TyCoVar] -- | We came across a custom type error and we have decided to report it. -- -- Example: -- -- type family F a where -- F a = TypeError (Text "error") -- -- err :: F () -- err = () -- -- Test cases: CustomTypeErrors0{1,2,3,4,5}, T12104. | UserTypeError Type -- | We want to report an out of scope variable or a typed hole. -- See 'HoleError'. | ReportHoleError Hole HoleError -- | Trying to unify an untouchable variable, e.g. a variable from an outer scope. -- -- Test case: Simple14 | UntouchableVariable { TcSolverReportMsg -> TcTyVar untouchableTyVar :: TyVar , TcSolverReportMsg -> Implication untouchableTyVarImplication :: Implication } -- | Cannot unify a variable, because of a type mismatch. | CannotUnifyVariable { TcSolverReportMsg -> MismatchMsg mismatchMsg :: MismatchMsg , TcSolverReportMsg -> CannotUnifyVariableReason cannotUnifyReason :: CannotUnifyVariableReason } -- | A mismatch between two types. | Mismatch { mismatchMsg :: MismatchMsg , TcSolverReportMsg -> Maybe TyVarInfo mismatchTyVarInfo :: Maybe TyVarInfo , TcSolverReportMsg -> [AmbiguityInfo] mismatchAmbiguityInfo :: [AmbiguityInfo] , TcSolverReportMsg -> Maybe CoercibleMsg mismatchCoercibleInfo :: Maybe CoercibleMsg } -- | A violation of the representation-polymorphism invariants. -- -- See 'FixedRuntimeRepErrorInfo' and 'FixedRuntimeRepContext' for more information. | FixedRuntimeRepError [FixedRuntimeRepErrorInfo] -- | An equality between two types is blocked on a kind equality -- between their kinds. -- -- Test cases: none. | BlockedEquality ErrorItem -- These are for the "blocked" equalities, as described in -- Note [Equalities with incompatible kinds] in GHC.Tc.Solver.Canonical, -- wrinkle (2). There should always be another unsolved wanted around, -- which will ordinarily suppress this message. But this can still be printed out -- with -fdefer-type-errors (sigh), so we must produce a message. -- | Something was not applied to sufficiently many arguments. -- -- Example: -- -- instance Eq Maybe where {..} -- -- Test case: T11563. | ExpectingMoreArguments Int TypedThing -- | Trying to use an unbound implicit parameter. -- -- Example: -- -- foo :: Int -- foo = ?param -- -- Test case: tcfail130. | UnboundImplicitParams (NE.NonEmpty ErrorItem) -- | A constraint couldn't be solved because it contains -- ambiguous type variables. -- -- Example: -- -- class C a b where -- f :: (a,b) -- -- x = fst f -- -- -- Test case: T4921. | AmbiguityPreventsSolvingCt ErrorItem -- ^ always a class constraint ([TyVar], [TyVar]) -- ^ ambiguous kind and type variables, respectively -- | Could not solve a constraint; there were several unifying candidate instances -- but no matching instances. This is used to report as much useful information -- as possible about why we couldn't choose any instance, e.g. because of -- ambiguous type variables. | CannotResolveInstance { TcSolverReportMsg -> ErrorItem cannotResolve_item :: ErrorItem , TcSolverReportMsg -> [ClsInst] cannotResolve_unifiers :: [ClsInst] , TcSolverReportMsg -> [ClsInst] cannotResolve_candidates :: [ClsInst] , TcSolverReportMsg -> [ImportError] cannotResolve_importErrors :: [ImportError] , TcSolverReportMsg -> [GhcHint] cannotResolve_suggestions :: [GhcHint] , TcSolverReportMsg -> RelevantBindings cannotResolve_relevant_bindings :: RelevantBindings } -- TODO: remove the fields of type [GhcHint] and RelevantBindings, -- in order to handle them uniformly with other diagnostic messages. -- | Could not solve a constraint using available instances -- because the instances overlap. -- -- Test cases: tcfail118, tcfail121, tcfail218. | OverlappingInstances { TcSolverReportMsg -> ErrorItem overlappingInstances_item :: ErrorItem , TcSolverReportMsg -> NonEmpty ClsInst overlappingInstances_matches :: NE.NonEmpty ClsInst , TcSolverReportMsg -> [ClsInst] overlappingInstances_unifiers :: [ClsInst] } -- | Could not solve a constraint from instances because -- instances declared in a Safe module cannot overlap instances -- from other modules (with -XSafeHaskell). -- -- Test cases: SH_Overlap{1,2,5,6,7,11}. | UnsafeOverlap { TcSolverReportMsg -> ErrorItem unsafeOverlap_item :: ErrorItem , TcSolverReportMsg -> ClsInst unsafeOverlap_match :: ClsInst , TcSolverReportMsg -> NonEmpty ClsInst unsafeOverlapped :: NE.NonEmpty ClsInst } deriving (forall x. TcSolverReportMsg -> Rep TcSolverReportMsg x) -> (forall x. Rep TcSolverReportMsg x -> TcSolverReportMsg) -> Generic TcSolverReportMsg forall x. Rep TcSolverReportMsg x -> TcSolverReportMsg forall x. TcSolverReportMsg -> Rep TcSolverReportMsg x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. TcSolverReportMsg -> Rep TcSolverReportMsg x from :: forall x. TcSolverReportMsg -> Rep TcSolverReportMsg x $cto :: forall x. Rep TcSolverReportMsg x -> TcSolverReportMsg to :: forall x. Rep TcSolverReportMsg x -> TcSolverReportMsg Generic data MismatchMsg = -- | Couldn't unify two types or kinds. -- -- Example: -- -- 3 + 3# -- can't match a lifted type with an unlifted type -- -- Test cases: T1396, T8263, ... BasicMismatch { MismatchMsg -> MismatchEA mismatch_ea :: MismatchEA -- ^ Should this be phrased in terms of expected vs actual? , MismatchMsg -> ErrorItem mismatch_item :: ErrorItem -- ^ The constraint in which the mismatch originated. , MismatchMsg -> Type mismatch_ty1 :: Type -- ^ First type (the expected type if if mismatch_ea is True) , MismatchMsg -> Type mismatch_ty2 :: Type -- ^ Second type (the actual type if mismatch_ea is True) , MismatchMsg -> Maybe WhenMatching mismatch_whenMatching :: Maybe WhenMatching , MismatchMsg -> Maybe SameOccInfo mismatch_mb_same_occ :: Maybe SameOccInfo } -- | A type has an unexpected kind. -- -- Test cases: T2994, T7609, ... | KindMismatch { MismatchMsg -> TypedThing kmismatch_what :: TypedThing -- ^ What thing is 'kmismatch_actual' the kind of? , MismatchMsg -> Type kmismatch_expected :: Type , MismatchMsg -> Type kmismatch_actual :: Type } -- TODO: combine with 'BasicMismatch'. -- | A mismatch between two types, which arose from a type equality. -- -- Test cases: T1470, tcfail212. | TypeEqMismatch { MismatchMsg -> Bool teq_mismatch_ppr_explicit_kinds :: Bool , MismatchMsg -> ErrorItem teq_mismatch_item :: ErrorItem , MismatchMsg -> Type teq_mismatch_ty1 :: Type , MismatchMsg -> Type teq_mismatch_ty2 :: Type , MismatchMsg -> Type teq_mismatch_expected :: Type -- ^ The overall expected type , MismatchMsg -> Type teq_mismatch_actual :: Type -- ^ The overall actual type , MismatchMsg -> Maybe TypedThing teq_mismatch_what :: Maybe TypedThing -- ^ What thing is 'teq_mismatch_actual' the kind of? , MismatchMsg -> Maybe SameOccInfo teq_mb_same_occ :: Maybe SameOccInfo } -- TODO: combine with 'BasicMismatch'. -- | Couldn't solve some Wanted constraints using the Givens. -- Used for messages such as @"No instance for ..."@ and -- @"Could not deduce ... from"@. | CouldNotDeduce { MismatchMsg -> [Implication] cnd_user_givens :: [Implication] -- | The Wanted constraints we couldn't solve. -- -- N.B.: the 'ErrorItem' at the head of the list has been tidied, -- perhaps not the others. , MismatchMsg -> NonEmpty ErrorItem cnd_wanted :: NE.NonEmpty ErrorItem -- | Some additional info consumed by 'mk_supplementary_ea_msg'. , MismatchMsg -> Maybe CND_Extra cnd_extra :: Maybe CND_Extra } deriving (forall x. MismatchMsg -> Rep MismatchMsg x) -> (forall x. Rep MismatchMsg x -> MismatchMsg) -> Generic MismatchMsg forall x. Rep MismatchMsg x -> MismatchMsg forall x. MismatchMsg -> Rep MismatchMsg x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. MismatchMsg -> Rep MismatchMsg x from :: forall x. MismatchMsg -> Rep MismatchMsg x $cto :: forall x. Rep MismatchMsg x -> MismatchMsg to :: forall x. Rep MismatchMsg x -> MismatchMsg Generic -- | Construct a basic mismatch message between two types. -- -- See 'pprMismatchMsg' for how such a message is displayed to users. mkBasicMismatchMsg :: MismatchEA -> ErrorItem -> Type -> Type -> MismatchMsg mkBasicMismatchMsg :: MismatchEA -> ErrorItem -> Type -> Type -> MismatchMsg mkBasicMismatchMsg MismatchEA ea ErrorItem item Type ty1 Type ty2 = BasicMismatch { mismatch_ea :: MismatchEA mismatch_ea = MismatchEA ea , mismatch_item :: ErrorItem mismatch_item = ErrorItem item , mismatch_ty1 :: Type mismatch_ty1 = Type ty1 , mismatch_ty2 :: Type mismatch_ty2 = Type ty2 , mismatch_whenMatching :: Maybe WhenMatching mismatch_whenMatching = Maybe WhenMatching forall a. Maybe a Nothing , mismatch_mb_same_occ :: Maybe SameOccInfo mismatch_mb_same_occ = Maybe SameOccInfo forall a. Maybe a Nothing } -- | Whether to use expected/actual in a type mismatch message. data MismatchEA -- | Don't use expected/actual. = NoEA -- | Use expected/actual. | EA { MismatchEA -> Maybe ExpectedActualInfo mismatch_mbEA :: Maybe ExpectedActualInfo -- ^ Whether to also mention type synonym expansion. } data CannotUnifyVariableReason = -- | A type equality between a type variable and a polytype. -- -- Test cases: T12427a, T2846b, T10194, ... CannotUnifyWithPolytype ErrorItem TyVar Type (Maybe TyVarInfo) -- | An occurs check. | OccursCheck { CannotUnifyVariableReason -> [TcTyVar] occursCheckInterestingTyVars :: [TyVar] , CannotUnifyVariableReason -> [AmbiguityInfo] occursCheckAmbiguityInfos :: [AmbiguityInfo] } -- | A skolem type variable escapes its scope. -- -- Example: -- -- data Ex where { MkEx :: a -> MkEx } -- foo (MkEx x) = x -- -- Test cases: TypeSkolEscape, T11142. | SkolemEscape ErrorItem Implication [TyVar] -- | Can't unify the type variable with the other type -- due to the kind of type variable it is. -- -- For example, trying to unify a 'SkolemTv' with the -- type Int, or with a 'TyVarTv'. | DifferentTyVars TyVarInfo | RepresentationalEq TyVarInfo (Maybe CoercibleMsg) deriving (forall x. CannotUnifyVariableReason -> Rep CannotUnifyVariableReason x) -> (forall x. Rep CannotUnifyVariableReason x -> CannotUnifyVariableReason) -> Generic CannotUnifyVariableReason forall x. Rep CannotUnifyVariableReason x -> CannotUnifyVariableReason forall x. CannotUnifyVariableReason -> Rep CannotUnifyVariableReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. CannotUnifyVariableReason -> Rep CannotUnifyVariableReason x from :: forall x. CannotUnifyVariableReason -> Rep CannotUnifyVariableReason x $cto :: forall x. Rep CannotUnifyVariableReason x -> CannotUnifyVariableReason to :: forall x. Rep CannotUnifyVariableReason x -> CannotUnifyVariableReason Generic -- | Report a mismatch error without any extra -- information. mkPlainMismatchMsg :: MismatchMsg -> TcSolverReportMsg mkPlainMismatchMsg :: MismatchMsg -> TcSolverReportMsg mkPlainMismatchMsg MismatchMsg msg = Mismatch { mismatchMsg :: MismatchMsg mismatchMsg = MismatchMsg msg , mismatchTyVarInfo :: Maybe TyVarInfo mismatchTyVarInfo = Maybe TyVarInfo forall a. Maybe a Nothing , mismatchAmbiguityInfo :: [AmbiguityInfo] mismatchAmbiguityInfo = [] , mismatchCoercibleInfo :: Maybe CoercibleMsg mismatchCoercibleInfo = Maybe CoercibleMsg forall a. Maybe a Nothing } -- | Additional information to be given in a 'CouldNotDeduce' message, -- which is then passed on to 'mk_supplementary_ea_msg'. data CND_Extra = CND_Extra TypeOrKind Type Type -- | A cue to print out information about type variables, -- e.g. where they were bound, when there is a mismatch @tv1 ~ ty2@. data TyVarInfo = TyVarInfo { TyVarInfo -> TcTyVar thisTyVar :: TyVar , TyVarInfo -> Maybe Implication thisTyVarIsUntouchable :: Maybe Implication , TyVarInfo -> Maybe TcTyVar otherTy :: Maybe TyVar } -- | Add some information to disambiguate errors in which -- two 'Names' would otherwise appear to be identical. -- -- See Note [Disambiguating (X ~ X) errors]. data SameOccInfo = SameOcc { SameOccInfo -> Bool sameOcc_same_pkg :: Bool -- ^ Whether the two 'Name's also came from the same package. , SameOccInfo -> Name sameOcc_lhs :: Name , SameOccInfo -> Name sameOcc_rhs :: Name } -- | Add some information about ambiguity data AmbiguityInfo -- | Some type variables remained ambiguous: print them to the user. = Ambiguity { AmbiguityInfo -> Bool lead_with_ambig_msg :: Bool -- ^ True <=> start the message with "Ambiguous type variable ..." -- False <=> create a message of the form "The type variable is ambiguous." , AmbiguityInfo -> ([TcTyVar], [TcTyVar]) ambig_tyvars :: ([TyVar], [TyVar]) -- ^ Ambiguous kind and type variables, respectively. -- Guaranteed to not both be empty. } -- | Remind the user that a particular type family is not injective. | NonInjectiveTyFam TyCon -- | Expected/actual information. data ExpectedActualInfo -- | Display the expected and actual types. = ExpectedActual { ExpectedActualInfo -> Type ea_expected, ExpectedActualInfo -> Type ea_actual :: Type } -- | Display the expected and actual types, after expanding type synonyms. | ExpectedActualAfterTySynExpansion { ExpectedActualInfo -> Type ea_expanded_expected, ExpectedActualInfo -> Type ea_expanded_actual :: Type } -- | Explain how a kind equality originated. data WhenMatching = WhenMatching TcType TcType CtOrigin (Maybe TypeOrKind) deriving (forall x. WhenMatching -> Rep WhenMatching x) -> (forall x. Rep WhenMatching x -> WhenMatching) -> Generic WhenMatching forall x. Rep WhenMatching x -> WhenMatching forall x. WhenMatching -> Rep WhenMatching x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. WhenMatching -> Rep WhenMatching x from :: forall x. WhenMatching -> Rep WhenMatching x $cto :: forall x. Rep WhenMatching x -> WhenMatching to :: forall x. Rep WhenMatching x -> WhenMatching Generic -- | Some form of @"not in scope"@ error. See also the 'OutOfScopeHole' -- constructor of 'HoleError'. data NotInScopeError -- | A run-of-the-mill @"not in scope"@ error. = NotInScope -- | An exact 'Name' was not in scope. -- -- This usually indicates a problem with a Template Haskell splice. -- -- Test cases: T5971, T18263. | NoExactName Name -- The same exact 'Name' occurs in multiple name-spaces. -- -- This usually indicates a problem with a Template Haskell splice. -- -- Test case: T7241. | SameName [GlobalRdrElt] -- ^ always at least 2 elements -- A type signature, fixity declaration, pragma, standalone kind signature... -- is missing an associated binding. | MissingBinding SDoc [GhcHint] -- TODO: remove the SDoc argument. -- | Couldn't find a top-level binding. -- -- Happens when specifying an annotation for something that -- is not in scope. -- -- Test cases: annfail01, annfail02, annfail11. | NoTopLevelBinding -- | A class doesn't have a method with this name, -- or, a class doesn't have an associated type with this name, -- or, a record doesn't have a record field with this name. | UnknownSubordinate SDoc deriving (forall x. NotInScopeError -> Rep NotInScopeError x) -> (forall x. Rep NotInScopeError x -> NotInScopeError) -> Generic NotInScopeError forall x. Rep NotInScopeError x -> NotInScopeError forall x. NotInScopeError -> Rep NotInScopeError x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. NotInScopeError -> Rep NotInScopeError x from :: forall x. NotInScopeError -> Rep NotInScopeError x $cto :: forall x. Rep NotInScopeError x -> NotInScopeError to :: forall x. Rep NotInScopeError x -> NotInScopeError Generic -- | Create a @"not in scope"@ error message for the given 'RdrName'. mkTcRnNotInScope :: RdrName -> NotInScopeError -> TcRnMessage mkTcRnNotInScope :: RdrName -> NotInScopeError -> TcRnMessage mkTcRnNotInScope RdrName rdr NotInScopeError err = NotInScopeError -> RdrName -> [ImportError] -> [GhcHint] -> TcRnMessage TcRnNotInScope NotInScopeError err RdrName rdr [] [GhcHint] noHints -- | Configuration for pretty-printing valid hole fits. data HoleFitDispConfig = HFDC { HoleFitDispConfig -> Bool showWrap, HoleFitDispConfig -> Bool showWrapVars, HoleFitDispConfig -> Bool showType, HoleFitDispConfig -> Bool showProv, HoleFitDispConfig -> Bool showMatches :: Bool } -- | Report an error involving a 'Hole'. -- -- This could be an out of scope data constructor or variable, -- a typed hole, or a wildcard in a type. data HoleError -- | Report an out-of-scope data constructor or variable -- masquerading as an expression hole. -- -- See Note [Insoluble holes] in GHC.Tc.Types.Constraint. -- See 'NotInScopeError' for other not-in-scope errors. -- -- Test cases: T9177a. = OutOfScopeHole [ImportError] -- | Report a typed hole, or wildcard, with additional information. | HoleError HoleSort [TcTyVar] -- Other type variables which get computed on the way. [(SkolemInfoAnon, [TcTyVar])] -- Zonked and grouped skolems for the type of the hole. -- | A message that aims to explain why two types couldn't be seen -- to be representationally equal. data CoercibleMsg -- | Not knowing the role of a type constructor prevents us from -- concluding that two types are representationally equal. -- -- Example: -- -- foo :: Applicative m => m (Sum Int) -- foo = coerce (pure $ 1 :: Int) -- -- We don't know what role `m` has, so we can't coerce `m Int` to `m (Sum Int)`. -- -- Test cases: T8984, TcCoercibleFail. = UnknownRoles Type -- | The fact that a 'TyCon' is abstract prevents us from decomposing -- a 'TyConApp' and deducing that two types are representationally equal. -- -- Test cases: none. | TyConIsAbstract TyCon -- | We can't unwrap a newtype whose constructor is not in scope. -- -- Example: -- -- import Data.Ord (Down) -- NB: not importing the constructor -- foo :: Int -> Down Int -- foo = coerce -- -- Test cases: TcCoercibleFail. | OutOfScopeNewtypeConstructor TyCon DataCon -- | Explain a problem with an import. data ImportError -- | Couldn't find a module with the requested name. = MissingModule ModuleName -- | The imported modules don't export what we're looking for. | ModulesDoNotExport (NE.NonEmpty Module) OccName -- | This datatype collates instances that match or unifier, -- in order to report an error message for an unsolved typeclass constraint. data PotentialInstances = PotentialInstances { PotentialInstances -> [ClsInst] matches :: [ClsInst] , PotentialInstances -> [ClsInst] unifiers :: [ClsInst] } -- | A collection of valid hole fits or refinement fits, -- in which some fits might have been suppressed. data FitsMbSuppressed = Fits { FitsMbSuppressed -> [HoleFit] fits :: [HoleFit] , FitsMbSuppressed -> Bool fitsSuppressed :: Bool -- ^ Whether we have suppressed any fits because there were too many. } -- | A collection of hole fits and refinement fits. data ValidHoleFits = ValidHoleFits { ValidHoleFits -> FitsMbSuppressed holeFits :: FitsMbSuppressed , ValidHoleFits -> FitsMbSuppressed refinementFits :: FitsMbSuppressed } noValidHoleFits :: ValidHoleFits noValidHoleFits :: ValidHoleFits noValidHoleFits = FitsMbSuppressed -> FitsMbSuppressed -> ValidHoleFits ValidHoleFits ([HoleFit] -> Bool -> FitsMbSuppressed Fits [] Bool False) ([HoleFit] -> Bool -> FitsMbSuppressed Fits [] Bool False) data RelevantBindings = RelevantBindings { RelevantBindings -> [(Name, Type)] relevantBindingNamesAndTys :: [(Name, Type)] , RelevantBindings -> Bool ranOutOfFuel :: Bool -- ^ Whether we ran out of fuel generating the bindings. } -- | Display some relevant bindings. pprRelevantBindings :: RelevantBindings -> SDoc -- This function should be in "GHC.Tc.Errors.Ppr", -- but it's here for the moment as it's needed in "GHC.Tc.Errors". pprRelevantBindings :: RelevantBindings -> SDoc pprRelevantBindings (RelevantBindings [(Name, Type)] bds Bool ran_out_of_fuel) = Bool -> SDoc -> SDoc forall doc. IsOutput doc => Bool -> doc -> doc ppUnless ([(Name, Type)] -> Bool forall a. [a] -> Bool forall (t :: * -> *) a. Foldable t => t a -> Bool null [(Name, Type)] rel_bds) (SDoc -> SDoc) -> SDoc -> SDoc forall a b. (a -> b) -> a -> b $ SDoc -> Int -> SDoc -> SDoc hang (String -> SDoc forall doc. IsLine doc => String -> doc text String "Relevant bindings include") Int 2 ([SDoc] -> SDoc forall doc. IsDoc doc => [doc] -> doc vcat (((Name, Type) -> SDoc) -> [(Name, Type)] -> [SDoc] forall a b. (a -> b) -> [a] -> [b] map (Name, Type) -> SDoc forall {a} {a}. (OutputableBndr a, NamedThing a, Outputable a) => (a, a) -> SDoc ppr_binding [(Name, Type)] rel_bds) SDoc -> SDoc -> SDoc forall doc. IsDoc doc => doc -> doc -> doc $$ Bool -> SDoc -> SDoc forall doc. IsOutput doc => Bool -> doc -> doc ppWhen Bool ran_out_of_fuel SDoc discardMsg) where ppr_binding :: (a, a) -> SDoc ppr_binding (a nm, a tidy_ty) = [SDoc] -> SDoc forall doc. IsLine doc => [doc] -> doc sep [ a -> SDoc forall a. OutputableBndr a => a -> SDoc pprPrefixOcc a nm SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> SDoc dcolon SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> a -> SDoc forall a. Outputable a => a -> SDoc ppr a tidy_ty , Int -> SDoc -> SDoc nest Int 2 (SDoc -> SDoc forall doc. IsLine doc => doc -> doc parens (String -> SDoc forall doc. IsLine doc => String -> doc text String "bound at" SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> SrcLoc -> SDoc forall a. Outputable a => a -> SDoc ppr (a -> SrcLoc forall a. NamedThing a => a -> SrcLoc getSrcLoc a nm)))] rel_bds :: [(Name, Type)] rel_bds = ((Name, Type) -> Bool) -> [(Name, Type)] -> [(Name, Type)] forall a. (a -> Bool) -> [a] -> [a] filter (Bool -> Bool not (Bool -> Bool) -> ((Name, Type) -> Bool) -> (Name, Type) -> Bool forall b c a. (b -> c) -> (a -> b) -> a -> c . SrcSpan -> Bool isGeneratedSrcSpan (SrcSpan -> Bool) -> ((Name, Type) -> SrcSpan) -> (Name, Type) -> Bool forall b c a. (b -> c) -> (a -> b) -> a -> c . Name -> SrcSpan forall a. NamedThing a => a -> SrcSpan getSrcSpan (Name -> SrcSpan) -> ((Name, Type) -> Name) -> (Name, Type) -> SrcSpan forall b c a. (b -> c) -> (a -> b) -> a -> c . (Name, Type) -> Name forall a b. (a, b) -> a fst) [(Name, Type)] bds discardMsg :: SDoc discardMsg :: SDoc discardMsg = String -> SDoc forall doc. IsLine doc => String -> doc text String "(Some bindings suppressed;" SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> String -> SDoc forall doc. IsLine doc => String -> doc text String "use -fmax-relevant-binds=N or -fno-max-relevant-binds)" data PromotionErr = TyConPE -- TyCon used in a kind before we are ready -- data T :: T -> * where ... | ClassPE -- Ditto Class | FamDataConPE -- Data constructor for a data family -- See Note [AFamDataCon: not promoting data family constructors] -- in GHC.Tc.Utils.Env. | ConstrainedDataConPE PredType -- Data constructor with a non-equality context -- See Note [Constraints in kinds] in GHC.Core.TyCo.Rep | PatSynPE -- Pattern synonyms -- See Note [Don't promote pattern synonyms] in GHC.Tc.Utils.Env | RecDataConPE -- Data constructor in a recursive loop -- See Note [Recursion and promoting data constructors] in GHC.Tc.TyCl | TermVariablePE -- See Note [Promoted variables in types] | NoDataKindsDC -- -XDataKinds not enabled (for a datacon) instance Outputable PromotionErr where ppr :: PromotionErr -> SDoc ppr PromotionErr ClassPE = String -> SDoc forall doc. IsLine doc => String -> doc text String "ClassPE" ppr PromotionErr TyConPE = String -> SDoc forall doc. IsLine doc => String -> doc text String "TyConPE" ppr PromotionErr PatSynPE = String -> SDoc forall doc. IsLine doc => String -> doc text String "PatSynPE" ppr PromotionErr FamDataConPE = String -> SDoc forall doc. IsLine doc => String -> doc text String "FamDataConPE" ppr (ConstrainedDataConPE Type pred) = String -> SDoc forall doc. IsLine doc => String -> doc text String "ConstrainedDataConPE" SDoc -> SDoc -> SDoc forall doc. IsLine doc => doc -> doc -> doc <+> SDoc -> SDoc forall doc. IsLine doc => doc -> doc parens (Type -> SDoc forall a. Outputable a => a -> SDoc ppr Type pred) ppr PromotionErr RecDataConPE = String -> SDoc forall doc. IsLine doc => String -> doc text String "RecDataConPE" ppr PromotionErr NoDataKindsDC = String -> SDoc forall doc. IsLine doc => String -> doc text String "NoDataKindsDC" ppr PromotionErr TermVariablePE = String -> SDoc forall doc. IsLine doc => String -> doc text String "TermVariablePE" pprPECategory :: PromotionErr -> SDoc pprPECategory :: PromotionErr -> SDoc pprPECategory = String -> SDoc forall doc. IsLine doc => String -> doc text (String -> SDoc) -> (PromotionErr -> String) -> PromotionErr -> SDoc forall b c a. (b -> c) -> (a -> b) -> a -> c . ShowS capitalise ShowS -> (PromotionErr -> String) -> PromotionErr -> String forall b c a. (b -> c) -> (a -> b) -> a -> c . PromotionErr -> String peCategory peCategory :: PromotionErr -> String peCategory :: PromotionErr -> String peCategory PromotionErr ClassPE = String "class" peCategory PromotionErr TyConPE = String "type constructor" peCategory PromotionErr PatSynPE = String "pattern synonym" peCategory PromotionErr FamDataConPE = String "data constructor" peCategory ConstrainedDataConPE{} = String "data constructor" peCategory PromotionErr RecDataConPE = String "data constructor" peCategory PromotionErr NoDataKindsDC = String "data constructor" peCategory PromotionErr TermVariablePE = String "term variable" -- | Stores the information to be reported in a representation-polymorphism -- error message. data FixedRuntimeRepErrorInfo = FRR_Info { FixedRuntimeRepErrorInfo -> FixedRuntimeRepOrigin frr_info_origin :: FixedRuntimeRepOrigin -- ^ What is the original type we checked for -- representation-polymorphism, and what specific -- check did we perform? , FixedRuntimeRepErrorInfo -> Maybe (TcTyVar, Type) frr_info_not_concrete :: Maybe (TcTyVar, TcType) -- ^ Which non-concrete type did we try to -- unify this concrete type variable with? } {- ************************************************************************ * * \subsection{Contexts for renaming errors} * * ************************************************************************ -} -- AZ:TODO: Change these all to be Name instead of RdrName. -- Merge TcType.UserTypeContext in to it. data HsDocContext = TypeSigCtx SDoc | StandaloneKindSigCtx SDoc | PatCtx | SpecInstSigCtx | DefaultDeclCtx | ForeignDeclCtx (LocatedN RdrName) | DerivDeclCtx | RuleCtx FastString | TyDataCtx (LocatedN RdrName) | TySynCtx (LocatedN RdrName) | TyFamilyCtx (LocatedN RdrName) | FamPatCtx (LocatedN RdrName) -- The patterns of a type/data family instance | ConDeclCtx [LocatedN Name] | ClassDeclCtx (LocatedN RdrName) | ExprWithTySigCtx | TypBrCtx | HsTypeCtx | HsTypePatCtx | GHCiCtx | SpliceTypeCtx (LHsType GhcPs) | ClassInstanceCtx | GenericCtx SDoc -- | Context for a mismatch in the number of arguments data MatchArgsContext = EquationArgs !Name -- ^ Name of the function | PatternArgs !(HsMatchContext GhcTc) -- ^ Pattern match specifics -- | The information necessary to report mismatched -- numbers of arguments in a match group. data MatchArgBadMatches where MatchArgMatches :: { () matchArgFirstMatch :: LocatedA (Match GhcRn body) , () matchArgBadMatches :: NE.NonEmpty (LocatedA (Match GhcRn body)) } -> MatchArgBadMatches -- | The phase in which an exception was encountered when dealing with a TH splice data SplicePhase = SplicePhase_Run | SplicePhase_CompileAndLink data LookupTHInstNameErrReason = NoMatchesFound | CouldNotDetermineInstance data UnrepresentableTypeDescr = LinearInvisibleArgument | CoercionsInTypes -- | The context for an "empty statement group" error. data EmptyStatementGroupErrReason = EmptyStmtsGroupInParallelComp -- ^ Empty statement group in a parallel list comprehension | EmptyStmtsGroupInTransformListComp -- ^ Empty statement group in a transform list comprehension -- -- Example: -- [() | then ()] | EmptyStmtsGroupInDoNotation HsDoFlavour -- ^ Empty statement group in do notation -- -- Example: -- do | EmptyStmtsGroupInArrowNotation -- ^ Empty statement group in arrow notation -- -- Example: -- proc () -> do deriving ((forall x. EmptyStatementGroupErrReason -> Rep EmptyStatementGroupErrReason x) -> (forall x. Rep EmptyStatementGroupErrReason x -> EmptyStatementGroupErrReason) -> Generic EmptyStatementGroupErrReason forall x. Rep EmptyStatementGroupErrReason x -> EmptyStatementGroupErrReason forall x. EmptyStatementGroupErrReason -> Rep EmptyStatementGroupErrReason x forall a. (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a $cfrom :: forall x. EmptyStatementGroupErrReason -> Rep EmptyStatementGroupErrReason x from :: forall x. EmptyStatementGroupErrReason -> Rep EmptyStatementGroupErrReason x $cto :: forall x. Rep EmptyStatementGroupErrReason x -> EmptyStatementGroupErrReason to :: forall x. Rep EmptyStatementGroupErrReason x -> EmptyStatementGroupErrReason Generic) -- | An existential wrapper around @'StmtLR' GhcPs GhcPs body@. data UnexpectedStatement where UnexpectedStatement :: Outputable (StmtLR GhcPs GhcPs body) => StmtLR GhcPs GhcPs body -> UnexpectedStatement