Safe Haskell	None
Language	Haskell2010

FamInstEnv

Contents

CoAxioms

Synopsis

Documentation

data FamInst Source

Constructors

FamInst
Fields fi_axiom :: CoAxiom Unbranched fi_flavor :: FamFlavor fi_fam :: Name fi_tcs :: [Maybe Name] fi_tvs :: [TyVar] fi_tys :: [Type] fi_rhs :: Type

Instances

Outputable FamInst
NamedThing FamInst

data FamFlavor Source

Constructors

SynFamilyInst
DataFamilyInst TyCon

famInstAxiom :: FamInst -> CoAxiom Unbranched Source

famInstTyCon :: FamInst -> TyCon Source

famInstRHS :: FamInst -> Type Source

famInstsRepTyCons :: [FamInst] -> [TyCon] Source

famInstRepTyCon_maybe :: FamInst -> Maybe TyCon Source

dataFamInstRepTyCon :: FamInst -> TyCon Source

pprFamInst :: FamInst -> SDoc Source

pprFamInsts :: [FamInst] -> SDoc Source

mkImportedFamInst :: Name -> [Maybe Name] -> CoAxiom Unbranched -> FamInst Source

type FamInstEnvs = (FamInstEnv, FamInstEnv) Source

type FamInstEnv = UniqFM FamilyInstEnv Source

emptyFamInstEnv :: FamInstEnv Source

emptyFamInstEnvs :: (FamInstEnv, FamInstEnv) Source

extendFamInstEnv :: FamInstEnv -> FamInst -> FamInstEnv Source

deleteFromFamInstEnv :: FamInstEnv -> FamInst -> FamInstEnv Source

extendFamInstEnvList :: FamInstEnv -> [FamInst] -> FamInstEnv Source

identicalFamInstHead :: FamInst -> FamInst -> Bool Source

True when the LHSs are identical Used for overriding in GHCi

famInstEnvElts :: FamInstEnv -> [FamInst] Source

familyInstances :: (FamInstEnv, FamInstEnv) -> TyCon -> [FamInst] Source

orphNamesOfFamInst :: FamInst -> NameSet Source

Collects the names of the concrete types and type constructors that make up the LHS of a type family instance, including the family name itself.

For instance, given `type family Foo a b`: `type instance Foo (F (G (H a))) b = ...` would yield [Foo,F,G,H]

Used in the implementation of ":info" in GHCi.

CoAxioms

mkCoAxBranch :: [TyVar] -> [Type] -> Type -> SrcSpan -> CoAxBranch Source

mkBranchedCoAxiom :: Name -> TyCon -> [CoAxBranch] -> CoAxiom Branched Source

mkUnbranchedCoAxiom :: Name -> TyCon -> CoAxBranch -> CoAxiom Unbranched Source

mkSingleCoAxiom :: Name -> [TyVar] -> TyCon -> [Type] -> Type -> CoAxiom Unbranched Source

computeAxiomIncomps :: CoAxiom br -> CoAxiom br Source

data FamInstMatch Source

Constructors

FamInstMatch
Fields fim_instance :: FamInst fim_tys :: [Type]

Instances

Outputable FamInstMatch

lookupFamInstEnv :: FamInstEnvs -> TyCon -> [Type] -> [FamInstMatch] Source

lookupFamInstEnvConflicts :: FamInstEnvs -> FamInst -> [FamInstMatch] Source

isDominatedBy :: CoAxBranch -> [CoAxBranch] -> Bool Source

topNormaliseType :: FamInstEnvs -> Type -> Type Source

topNormaliseType_maybe :: FamInstEnvs -> Type -> Maybe (Coercion, Type) Source

Get rid of *outermost* (or toplevel) * type function redex * newtypes using appropriate coercions. Specifically, if topNormaliseType_maybe env ty = Maybe (co, ty') then (a) co :: ty ~ ty' (b) ty' is not a newtype, and is not a type-family redex

However, ty' can be something like (Maybe (F ty)), where (F ty) is a redex.

Its a bit like Type.repType, but handles type families too The coercion returned is always an R coercion

normaliseType :: FamInstEnvs -> Role -> Type -> (Coercion, Type) Source

normaliseTcApp :: FamInstEnvs -> Role -> TyCon -> [Type] -> (Coercion, Type) Source

reduceTyFamApp_maybe :: FamInstEnvs -> Role -> TyCon -> [Type] -> Maybe (Coercion, Type) Source

chooseBranch :: CoAxiom Branched -> [Type] -> Maybe (BranchIndex, [Type]) Source

flattenTys :: InScopeSet -> [Type] -> [Type] Source