    {-
    (c) The University of Glasgow 2006
    (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
    -}

    {-# LANGUAGE CPP #-}
    {-# LANGUAGE DeriveDataTypeable #-}
    {-# LANGUAGE FlexibleInstances #-}
    {-# LANGUAGE GADTs #-}
    {-# LANGUAGE LambdaCase #-}
    {-# LANGUAGE PatternSynonyms #-}

    -- |
    -- #name_types#
    -- GHC uses several kinds of name internally:
    --
    -- * 'GHC.Types.Name.Occurrence.OccName': see "GHC.Types.Name.Occurrence#name_types"
    --
    -- * 'GHC.Types.Name.Reader.RdrName' is the type of names that come directly from the parser. They
    --   have not yet had their scoping and binding resolved by the renamer and can be
    --   thought of to a first approximation as an 'GHC.Types.Name.Occurrence.OccName' with an optional module
    --   qualifier
    --
    -- * 'GHC.Types.Name.Name': see "GHC.Types.Name#name_types"
    --
    -- * 'GHC.Types.Id.Id': see "GHC.Types.Id#name_types"
    --
    -- * 'GHC.Types.Var.Var': see "GHC.Types.Var#name_types"

    module GHC.Types.Name.Reader (
            -- * The main type
            RdrName(..),    -- Constructors exported only to GHC.Iface.Binary

            -- ** Construction
            mkRdrUnqual, mkRdrQual,
            mkUnqual, mkVarUnqual, mkQual, mkOrig,
            nameRdrName, getRdrName,

            -- ** Destruction
            rdrNameOcc, rdrNameSpace, demoteRdrName, demoteRdrNameTv, promoteRdrName,
            isRdrDataCon, isRdrTyVar, isRdrTc, isQual, isQual_maybe, isUnqual,
            isOrig, isOrig_maybe, isExact, isExact_maybe, isSrcRdrName,

            -- * Local mapping of 'RdrName' to 'Name.Name'
            LocalRdrEnv, emptyLocalRdrEnv, extendLocalRdrEnv, extendLocalRdrEnvList,
            lookupLocalRdrEnv, lookupLocalRdrOcc,
            elemLocalRdrEnv, inLocalRdrEnvScope,
            localRdrEnvElts, minusLocalRdrEnv, minusLocalRdrEnvList,

            -- * Global mapping of 'RdrName' to 'GlobalRdrElt's
            GlobalRdrEnvX, GlobalRdrEnv, IfGlobalRdrEnv,
            emptyGlobalRdrEnv, mkGlobalRdrEnv, plusGlobalRdrEnv,
            extendGlobalRdrEnv, greOccName,
            pprGlobalRdrEnv, globalRdrEnvElts,

            -- ** Looking up 'GlobalRdrElt's
            FieldsOrSelectors(..), filterFieldGREs, allowGRE,

            LookupGRE(..), lookupGRE,
            WhichGREs(.., AllRelevantGREs, RelevantGREsFOS),
            greIsRelevant,
            LookupChild(..),

            lookupGRE_Name,
            lookupGRE_FieldLabel,
            getGRE_NameQualifier_maybes,
            transformGREs, pickGREs, pickGREsModExp,

            -- * GlobalRdrElts
            availFromGRE,
            greRdrNames, greSrcSpan, greQualModName,
            gresToAvailInfo,
            greDefinitionModule, greDefinitionSrcSpan,
            greFieldLabel_maybe,

            -- ** Global 'RdrName' mapping elements: 'GlobalRdrElt', 'Provenance', 'ImportSpec'
            GlobalRdrEltX(..), GlobalRdrElt, IfGlobalRdrElt, FieldGlobalRdrElt,
            greName, greNameSpace, greParent, greInfo,
            plusGRE, insertGRE,
            forceGlobalRdrEnv, hydrateGlobalRdrEnv,
            isLocalGRE, isImportedGRE, isRecFldGRE,
            fieldGREInfo,
            isDuplicateRecFldGRE, isNoFieldSelectorGRE, isFieldSelectorGRE,
            unQualOK, qualSpecOK, unQualSpecOK,
            pprNameProvenance,
            mkGRE, mkExactGRE, mkLocalGRE, mkLocalVanillaGRE, mkLocalTyConGRE,
            mkLocalConLikeGRE, mkLocalFieldGREs,
            gresToNameSet,

            -- ** Shadowing
            greClashesWith, shadowNames,

            -- ** Information attached to a 'GlobalRdrElt'
            ConLikeName(..),
            GREInfo(..), RecFieldInfo(..),
            plusGREInfo,
            recFieldConLike_maybe, recFieldInfo_maybe,
            fieldGRE_maybe, fieldGRELabel,

            -- ** Parent information
            Parent(..), greParent_maybe,
            mkParent, availParent,
            ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
            importSpecLoc, importSpecModule, isExplicitItem, bestImport,

            -- * Utils
            opIsAt
      ) where

    import GHC.Prelude

    import GHC.Data.Bag
    import GHC.Data.FastString
    import GHC.Data.Maybe

    import GHC.Types.Avail
    import GHC.Types.Basic
    import GHC.Types.GREInfo
    import GHC.Types.FieldLabel
    import GHC.Types.Name
    import GHC.Types.Name.Env
        ( NameEnv, nonDetNameEnvElts, emptyNameEnv, extendNameEnv_Acc )
    import GHC.Types.Name.Set
    import GHC.Types.SrcLoc as SrcLoc
    import GHC.Types.Unique
    import GHC.Types.Unique.FM
    import GHC.Types.Unique.Set
    import GHC.Builtin.Uniques ( isFldNSUnique )

    import GHC.Unit.Module

    import GHC.Utils.Misc as Utils
    import GHC.Utils.Outputable
    import GHC.Utils.Panic

    import Control.DeepSeq
    import Control.Monad ( guard )
    import Data.Data
    import Data.List ( sort )
    import qualified Data.List.NonEmpty as NE
    import qualified Data.Map.Strict as Map
    import qualified Data.Semigroup as S
    import System.IO.Unsafe ( unsafePerformIO )

    {-
    ************************************************************************
    *                                                                      *
    \subsection{The main data type}
    *                                                                      *
    ************************************************************************
    -}

    -- | Reader Name
    --
    -- Do not use the data constructors of RdrName directly: prefer the family
    -- of functions that creates them, such as 'mkRdrUnqual'
    --
    -- - Note: A Located RdrName will only have API Annotations if it is a
    --         compound one,
    --   e.g.
    --
    -- > `bar`
    -- > ( ~ )
    --
    -- - 'GHC.Parser.Annotation.AnnKeywordId' : 'GHC.Parser.Annotation.AnnType',
    --           'GHC.Parser.Annotation.AnnOpen'  @'('@ or @'['@ or @'[:'@,
    --           'GHC.Parser.Annotation.AnnClose' @')'@ or @']'@ or @':]'@,,
    --           'GHC.Parser.Annotation.AnnBackquote' @'`'@,
    --           'GHC.Parser.Annotation.AnnVal'
    --           'GHC.Parser.Annotation.AnnTilde',

    -- For details on above see Note [exact print annotations] in "GHC.Parser.Annotation"
    data RdrName
      = Unqual OccName
            -- ^ Unqualified  name
            --
            -- Used for ordinary, unqualified occurrences, e.g. @x@, @y@ or @Foo@.
            -- Create such a 'RdrName' with 'mkRdrUnqual'

      | Qual ModuleName OccName
            -- ^ Qualified name
            --
            -- A qualified name written by the user in
            -- /source/ code.  The module isn't necessarily
            -- the module where the thing is defined;
            -- just the one from which it is imported.
            -- Examples are @Bar.x@, @Bar.y@ or @Bar.Foo@.
            -- Create such a 'RdrName' with 'mkRdrQual'

      | Orig Module OccName
            -- ^ Original name
            --
            -- An original name; the module is the /defining/ module.
            -- This is used when GHC generates code that will be fed
            -- into the renamer (e.g. from deriving clauses), but where
            -- we want to say \"Use Prelude.map dammit\". One of these
            -- can be created with 'mkOrig'

      | Exact Name
            -- ^ Exact name
            --
            -- We know exactly the 'Name'. This is used:
            --
            --  (1) When the parser parses built-in syntax like @[]@
            --      and @(,)@, but wants a 'RdrName' from it
            --
            --  (2) By Template Haskell, when TH has generated a unique name
            --
            -- Such a 'RdrName' can be created by using 'getRdrName' on a 'Name'
      deriving Typeable RdrName
    Typeable RdrName =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> RdrName -> c RdrName)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c RdrName)
    -> (RdrName -> Constr)
    -> (RdrName -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c RdrName))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c RdrName))
    -> ((forall b. Data b => b -> b) -> RdrName -> RdrName)
    -> (forall r r'.
        (r -> r' -> r)
        -> r -> (forall d. Data d => d -> r') -> RdrName -> r)
    -> (forall r r'.
        (r' -> r -> r)
        -> r -> (forall d. Data d => d -> r') -> RdrName -> r)
    -> (forall u. (forall d. Data d => d -> u) -> RdrName -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> RdrName -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> RdrName -> m RdrName)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> RdrName -> m RdrName)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> RdrName -> m RdrName)
    -> Data RdrName
    RdrName -> Constr
    RdrName -> DataType
    (forall b. Data b => b -> b) -> RdrName -> RdrName
    forall a.
    Typeable a =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> a -> c a)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
    -> (a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall r r'.
        (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> RdrName -> u
    forall u. (forall d. Data d => d -> u) -> RdrName -> [u]
    forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c RdrName
    forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> RdrName -> c RdrName
    forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c RdrName)
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c RdrName)
    $cgfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> RdrName -> c RdrName
    gfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> RdrName -> c RdrName
    $cgunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c RdrName
    gunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c RdrName
    $ctoConstr :: RdrName -> Constr
    toConstr :: RdrName -> Constr
    $cdataTypeOf :: RdrName -> DataType
    dataTypeOf :: RdrName -> DataType
    $cdataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c RdrName)
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c RdrName)
    $cdataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c RdrName)
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c RdrName)
    $cgmapT :: (forall b. Data b => b -> b) -> RdrName -> RdrName
    gmapT :: (forall b. Data b => b -> b) -> RdrName -> RdrName
    $cgmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    gmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    $cgmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    gmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> RdrName -> r
    $cgmapQ :: forall u. (forall d. Data d => d -> u) -> RdrName -> [u]
    gmapQ :: forall u. (forall d. Data d => d -> u) -> RdrName -> [u]
    $cgmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> RdrName -> u
    gmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> RdrName -> u
    $cgmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    gmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    $cgmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    gmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    $cgmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    gmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> RdrName -> m RdrName
    Data

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Simple functions}
    *                                                                      *
    ************************************************************************
    -}

    instance HasOccName RdrName where
      occName :: RdrName -> OccName
    occName = RdrName -> OccName
    rdrNameOcc

    rdrNameOcc :: RdrName -> OccName
    rdrNameOcc :: RdrName -> OccName
    rdrNameOcc (Qual ModuleName
    _ OccName
    occ) = OccName
    occ
    rdrNameOcc (Unqual OccName
    occ) = OccName
    occ
    rdrNameOcc (Orig Module
    _ OccName
    occ) = OccName
    occ
    rdrNameOcc (Exact Name
    name) = Name -> OccName
    nameOccName Name
    name

    rdrNameSpace :: RdrName -> NameSpace
    rdrNameSpace :: RdrName -> NameSpace
    rdrNameSpace = OccName -> NameSpace
    occNameSpace (OccName -> NameSpace)
    -> (RdrName -> OccName) -> RdrName -> NameSpace
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . RdrName -> OccName
    rdrNameOcc

    -- demoteRdrName lowers the NameSpace of RdrName.
    -- See Note [Demotion] in GHC.Rename.Env
    demoteRdrName :: RdrName -> Maybe RdrName
    demoteRdrName :: RdrName -> Maybe RdrName
    demoteRdrName (Unqual OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap OccName -> RdrName
    Unqual (OccName -> Maybe OccName
    demoteOccName OccName
    occ)
    demoteRdrName (Qual ModuleName
    m OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap (ModuleName -> OccName -> RdrName
    Qual ModuleName
    m) (OccName -> Maybe OccName
    demoteOccName OccName
    occ)
    demoteRdrName (Orig Module
    _ OccName
    _) = Maybe RdrName
    forall a. Maybe a
    Nothing
    demoteRdrName (Exact Name
    _) = Maybe RdrName
    forall a. Maybe a
    Nothing

    demoteRdrNameTv :: RdrName -> Maybe RdrName
    demoteRdrNameTv :: RdrName -> Maybe RdrName
    demoteRdrNameTv (Unqual OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap OccName -> RdrName
    Unqual (OccName -> Maybe OccName
    demoteOccTvName OccName
    occ)
    demoteRdrNameTv (Qual ModuleName
    m OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap (ModuleName -> OccName -> RdrName
    Qual ModuleName
    m) (OccName -> Maybe OccName
    demoteOccTvName OccName
    occ)
    demoteRdrNameTv (Orig Module
    _ OccName
    _) = Maybe RdrName
    forall a. Maybe a
    Nothing
    demoteRdrNameTv (Exact Name
    _) = Maybe RdrName
    forall a. Maybe a
    Nothing

    -- promoteRdrName promotes the NameSpace of RdrName.
    -- See Note [Promotion] in GHC.Rename.Env.
    promoteRdrName :: RdrName -> Maybe RdrName
    promoteRdrName :: RdrName -> Maybe RdrName
    promoteRdrName (Unqual OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap OccName -> RdrName
    Unqual (OccName -> Maybe OccName
    promoteOccName OccName
    occ)
    promoteRdrName (Qual ModuleName
    m OccName
    occ) = (OccName -> RdrName) -> Maybe OccName -> Maybe RdrName
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap (ModuleName -> OccName -> RdrName
    Qual ModuleName
    m) (OccName -> Maybe OccName
    promoteOccName OccName
    occ)
    promoteRdrName (Orig Module
    _ OccName
    _) = Maybe RdrName
    forall a. Maybe a
    Nothing
    promoteRdrName (Exact Name
    _)  = Maybe RdrName
    forall a. Maybe a
    Nothing

            -- These two are the basic constructors
    mkRdrUnqual :: OccName -> RdrName
    mkRdrUnqual :: OccName -> RdrName
    mkRdrUnqual OccName
    occ = OccName -> RdrName
    Unqual OccName
    occ

    mkRdrQual :: ModuleName -> OccName -> RdrName
    mkRdrQual :: ModuleName -> OccName -> RdrName
    mkRdrQual ModuleName
    mod OccName
    occ = ModuleName -> OccName -> RdrName
    Qual ModuleName
    mod OccName
    occ

    mkOrig :: Module -> OccName -> RdrName
    mkOrig :: Module -> OccName -> RdrName
    mkOrig Module
    mod OccName
    occ = Module -> OccName -> RdrName
    Orig Module
    mod OccName
    occ

    ---------------
            -- These two are used when parsing source files
            -- They do encode the module and occurrence names
    mkUnqual :: NameSpace -> FastString -> RdrName
    mkUnqual :: NameSpace -> FastString -> RdrName
    mkUnqual NameSpace
    sp FastString
    n = OccName -> RdrName
    Unqual (NameSpace -> FastString -> OccName
    mkOccNameFS NameSpace
    sp FastString
    n)

    mkVarUnqual :: FastString -> RdrName
    mkVarUnqual :: FastString -> RdrName
    mkVarUnqual FastString
    n = OccName -> RdrName
    Unqual (FastString -> OccName
    mkVarOccFS FastString
    n)

    -- | Make a qualified 'RdrName' in the given namespace and where the 'ModuleName' and
    -- the 'OccName' are taken from the first and second elements of the tuple respectively
    mkQual :: NameSpace -> (FastString, FastString) -> RdrName
    mkQual :: NameSpace -> (FastString, FastString) -> RdrName
    mkQual NameSpace
    sp (FastString
    m, FastString
    n) = ModuleName -> OccName -> RdrName
    Qual (FastString -> ModuleName
    mkModuleNameFS FastString
    m) (NameSpace -> FastString -> OccName
    mkOccNameFS NameSpace
    sp FastString
    n)

    getRdrName :: NamedThing thing => thing -> RdrName
    getRdrName :: forall thing. NamedThing thing => thing -> RdrName
    getRdrName thing
    name = Name -> RdrName
    nameRdrName (thing -> Name
    forall a. NamedThing a => a -> Name
    getName thing
    name)

    nameRdrName :: Name -> RdrName
    nameRdrName :: Name -> RdrName
    nameRdrName Name
    name = Name -> RdrName
    Exact Name
    name
    -- Keep the Name even for Internal names, so that the
    -- unique is still there for debug printing, particularly
    -- of Types (which are converted to IfaceTypes before printing)

    nukeExact :: Name -> RdrName
    nukeExact :: Name -> RdrName
    nukeExact Name
    n
      | Name -> Bool
    isExternalName Name
    n = Module -> OccName -> RdrName
    Orig (HasDebugCallStack => Name -> Module
    Name -> Module
    nameModule Name
    n) (Name -> OccName
    nameOccName Name
    n)
      | Bool
    otherwise        = OccName -> RdrName
    Unqual (Name -> OccName
    nameOccName Name
    n)

    isRdrDataCon :: RdrName -> Bool
    isRdrTyVar   :: RdrName -> Bool
    isRdrTc      :: RdrName -> Bool

    isRdrDataCon :: RdrName -> Bool
    isRdrDataCon RdrName
    rn = OccName -> Bool
    isDataOcc (RdrName -> OccName
    rdrNameOcc RdrName
    rn)
    isRdrTyVar :: RdrName -> Bool
    isRdrTyVar   RdrName
    rn = OccName -> Bool
    isTvOcc   (RdrName -> OccName
    rdrNameOcc RdrName
    rn)
    isRdrTc :: RdrName -> Bool
    isRdrTc      RdrName
    rn = OccName -> Bool
    isTcOcc   (RdrName -> OccName
    rdrNameOcc RdrName
    rn)

    isSrcRdrName :: RdrName -> Bool
    isSrcRdrName :: RdrName -> Bool
    isSrcRdrName (Unqual OccName
    _) = Bool
    True
    isSrcRdrName (Qual ModuleName
    _ OccName
    _) = Bool
    True
    isSrcRdrName RdrName
    _          = Bool
    False

    isUnqual :: RdrName -> Bool
    isUnqual :: RdrName -> Bool
    isUnqual (Unqual OccName
    _) = Bool
    True
    isUnqual RdrName
    _          = Bool
    False

    isQual :: RdrName -> Bool
    isQual :: RdrName -> Bool
    isQual (Qual ModuleName
    _ OccName
    _) = Bool
    True
    isQual RdrName
    _          = Bool
    False

    isQual_maybe :: RdrName -> Maybe (ModuleName, OccName)
    isQual_maybe :: RdrName -> Maybe (ModuleName, OccName)
    isQual_maybe (Qual ModuleName
    m OccName
    n) = (ModuleName, OccName) -> Maybe (ModuleName, OccName)
    forall a. a -> Maybe a
    Just (ModuleName
    m,OccName
    n)
    isQual_maybe RdrName
    _          = Maybe (ModuleName, OccName)
    forall a. Maybe a
    Nothing

    isOrig :: RdrName -> Bool
    isOrig :: RdrName -> Bool
    isOrig (Orig Module
    _ OccName
    _) = Bool
    True
    isOrig RdrName
    _          = Bool
    False

    isOrig_maybe :: RdrName -> Maybe (Module, OccName)
    isOrig_maybe :: RdrName -> Maybe (Module, OccName)
    isOrig_maybe (Orig Module
    m OccName
    n) = (Module, OccName) -> Maybe (Module, OccName)
    forall a. a -> Maybe a
    Just (Module
    m,OccName
    n)
    isOrig_maybe RdrName
    _          = Maybe (Module, OccName)
    forall a. Maybe a
    Nothing

    isExact :: RdrName -> Bool
    isExact :: RdrName -> Bool
    isExact (Exact Name
    _) = Bool
    True
    isExact RdrName
    _         = Bool
    False

    isExact_maybe :: RdrName -> Maybe Name
    isExact_maybe :: RdrName -> Maybe Name
    isExact_maybe (Exact Name
    n) = Name -> Maybe Name
    forall a. a -> Maybe a
    Just Name
    n
    isExact_maybe RdrName
    _         = Maybe Name
    forall a. Maybe a
    Nothing

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Instances}
    *                                                                      *
    ************************************************************************
    -}

    instance Outputable RdrName where
        ppr :: RdrName -> SDoc
    ppr (Exact Name
    name)   = Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name
        ppr (Unqual OccName
    occ)   = OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr OccName
    occ
        ppr (Qual ModuleName
    mod OccName
    occ) = ModuleName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr ModuleName
    mod SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> SDoc
    forall doc. IsLine doc => doc
    dot SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr OccName
    occ
        ppr (Orig Module
    mod OccName
    occ) = (PprStyle -> SDoc) -> SDoc
    getPprStyle (\PprStyle
    sty -> PprStyle -> Module -> OccName -> SDoc
    pprModulePrefix PprStyle
    sty Module
    mod OccName
    occ SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr OccName
    occ)

    instance OutputableBndr RdrName where
        pprBndr :: BindingSite -> RdrName -> SDoc
    pprBndr BindingSite
    _ RdrName
    n
            | OccName -> Bool
    isTvOcc (RdrName -> OccName
    rdrNameOcc RdrName
    n) = Char -> SDoc
    forall doc. IsLine doc => Char -> doc
    char Char
    '@' SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> RdrName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RdrName
    n
            | Bool
    otherwise              = RdrName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RdrName
    n

        pprInfixOcc :: RdrName -> SDoc
    pprInfixOcc  RdrName
    rdr = Bool -> SDoc -> SDoc
    pprInfixVar  (OccName -> Bool
    isSymOcc (RdrName -> OccName
    rdrNameOcc RdrName
    rdr)) (RdrName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RdrName
    rdr)
        pprPrefixOcc :: RdrName -> SDoc
    pprPrefixOcc RdrName
    rdr
          | Just Name
    name <- RdrName -> Maybe Name
    isExact_maybe RdrName
    rdr = Name -> SDoc
    forall a. NamedThing a => a -> SDoc
    pprPrefixName Name
    name
                 -- pprPrefixName has some special cases, so
                 -- we delegate to them rather than reproduce them
          | Bool
    otherwise = Bool -> SDoc -> SDoc
    pprPrefixVar (OccName -> Bool
    isSymOcc (RdrName -> OccName
    rdrNameOcc RdrName
    rdr)) (RdrName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RdrName
    rdr)

    instance Eq RdrName where
        (Exact Name
    n1)    == :: RdrName -> RdrName -> Bool
    == (Exact Name
    n2)    = Name
    n1Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    ==Name
    n2
            -- Convert exact to orig
        (Exact Name
    n1)    == r2 :: RdrName
    r2@(Orig Module
    _ OccName
    _) = Name -> RdrName
    nukeExact Name
    n1 RdrName -> RdrName -> Bool
    forall a. Eq a => a -> a -> Bool
    == RdrName
    r2
        r1 :: RdrName
    r1@(Orig Module
    _ OccName
    _) == (Exact Name
    n2)    = RdrName
    r1 RdrName -> RdrName -> Bool
    forall a. Eq a => a -> a -> Bool
    == Name -> RdrName
    nukeExact Name
    n2

        (Orig Module
    m1 OccName
    o1)  == (Orig Module
    m2 OccName
    o2)  = Module
    m1Module -> Module -> Bool
    forall a. Eq a => a -> a -> Bool
    ==Module
    m2 Bool -> Bool -> Bool
    && OccName
    o1OccName -> OccName -> Bool
    forall a. Eq a => a -> a -> Bool
    ==OccName
    o2
        (Qual ModuleName
    m1 OccName
    o1)  == (Qual ModuleName
    m2 OccName
    o2)  = ModuleName
    m1ModuleName -> ModuleName -> Bool
    forall a. Eq a => a -> a -> Bool
    ==ModuleName
    m2 Bool -> Bool -> Bool
    && OccName
    o1OccName -> OccName -> Bool
    forall a. Eq a => a -> a -> Bool
    ==OccName
    o2
        (Unqual OccName
    o1)   == (Unqual OccName
    o2)   = OccName
    o1OccName -> OccName -> Bool
    forall a. Eq a => a -> a -> Bool
    ==OccName
    o2
        RdrName
    _             == RdrName
    _             = Bool
    False

    instance Ord RdrName where
        RdrName
    a <= :: RdrName -> RdrName -> Bool
    <= RdrName
    b = case (RdrName
    a RdrName -> RdrName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` RdrName
    b) of { Ordering
    LT -> Bool
    True;  Ordering
    EQ -> Bool
    True;  Ordering
    GT -> Bool
    False }
        RdrName
    a < :: RdrName -> RdrName -> Bool
    <  RdrName
    b = case (RdrName
    a RdrName -> RdrName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` RdrName
    b) of { Ordering
    LT -> Bool
    True;  Ordering
    EQ -> Bool
    False; Ordering
    GT -> Bool
    False }
        RdrName
    a >= :: RdrName -> RdrName -> Bool
    >= RdrName
    b = case (RdrName
    a RdrName -> RdrName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` RdrName
    b) of { Ordering
    LT -> Bool
    False; Ordering
    EQ -> Bool
    True;  Ordering
    GT -> Bool
    True  }
        RdrName
    a > :: RdrName -> RdrName -> Bool
    >  RdrName
    b = case (RdrName
    a RdrName -> RdrName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` RdrName
    b) of { Ordering
    LT -> Bool
    False; Ordering
    EQ -> Bool
    False; Ordering
    GT -> Bool
    True  }

            -- Exact < Unqual < Qual < Orig
            -- [Note: Apr 2004] We used to use nukeExact to convert Exact to Orig
            --      before comparing so that Prelude.map == the exact Prelude.map, but
            --      that meant that we reported duplicates when renaming bindings
            --      generated by Template Haskell; e.g
            --      do { n1 <- newName "foo"; n2 <- newName "foo";
            --           <decl involving n1,n2> }
            --      I think we can do without this conversion
        compare :: RdrName -> RdrName -> Ordering
    compare (Exact Name
    n1) (Exact Name
    n2) = Name
    n1 Name -> Name -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` Name
    n2
        compare (Exact Name
    _)  RdrName
    _          = Ordering
    LT

        compare (Unqual OccName
    _)   (Exact Name
    _)    = Ordering
    GT
        compare (Unqual OccName
    o1)  (Unqual  OccName
    o2) = OccName
    o1 OccName -> OccName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` OccName
    o2
        compare (Unqual OccName
    _)   RdrName
    _            = Ordering
    LT

        compare (Qual ModuleName
    _ OccName
    _)   (Exact Name
    _)    = Ordering
    GT
        compare (Qual ModuleName
    _ OccName
    _)   (Unqual OccName
    _)   = Ordering
    GT
        compare (Qual ModuleName
    m1 OccName
    o1) (Qual ModuleName
    m2 OccName
    o2) = OccName -> OccName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    compare OccName
    o1 OccName
    o2 Ordering -> Ordering -> Ordering
    forall a. Semigroup a => a -> a -> a
    S.<> ModuleName -> ModuleName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    compare ModuleName
    m1 ModuleName
    m2
        compare (Qual ModuleName
    _ OccName
    _)   (Orig Module
    _ OccName
    _)   = Ordering
    LT

        compare (Orig Module
    m1 OccName
    o1) (Orig Module
    m2 OccName
    o2) = OccName -> OccName -> Ordering
    forall a. Ord a => a -> a -> Ordering
    compare OccName
    o1 OccName
    o2 Ordering -> Ordering -> Ordering
    forall a. Semigroup a => a -> a -> a
    S.<> Module -> Module -> Ordering
    forall a. Ord a => a -> a -> Ordering
    compare Module
    m1 Module
    m2
        compare (Orig Module
    _ OccName
    _)   RdrName
    _            = Ordering
    GT

    {-
    ************************************************************************
    *                                                                      *
                            LocalRdrEnv
    *                                                                      *
    ************************************************************************
    -}

    {- Note [LocalRdrEnv]
    ~~~~~~~~~~~~~~~~~~~~~
    The LocalRdrEnv is used to store local bindings (let, where, lambda, case).

    * It is keyed by OccName, because we never use it for qualified names.

    * It maps the OccName to a Name.  That Name is almost always an
      Internal Name, but (hackily) it can be External too for top-level
      pattern bindings.  See Note [bindLocalNames for an External name]
      in GHC.Rename.Pat

    * We keep the current mapping (lre_env), *and* the set of all Names in
      scope (lre_in_scope).  Reason: see Note [Splicing Exact names] in
      GHC.Rename.Env.
    -}

    -- | Local Reader Environment
    -- See Note [LocalRdrEnv]
    data LocalRdrEnv = LRE { LocalRdrEnv -> OccEnv Name
    lre_env      :: OccEnv Name
                           , LocalRdrEnv -> NameSet
    lre_in_scope :: NameSet }

    instance Outputable LocalRdrEnv where
      ppr :: LocalRdrEnv -> SDoc
    ppr (LRE {lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env, lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns})
        = SDoc -> Int -> SDoc -> SDoc
    hang (String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "LocalRdrEnv {")
             Int
    2 ([SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "env =" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> (Name -> SDoc) -> OccEnv Name -> SDoc
    forall a. (a -> SDoc) -> OccEnv a -> SDoc
    pprOccEnv Name -> SDoc
    ppr_elt OccEnv Name
    env
                     , String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "in_scope ="
                        SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> UniqFM Name Name -> ([Name] -> SDoc) -> SDoc
    forall {k} (key :: k) a. UniqFM key a -> ([a] -> SDoc) -> SDoc
    pprUFM (NameSet -> UniqFM Name Name
    forall a. UniqSet a -> UniqFM a a
    getUniqSet NameSet
    ns) (SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    braces (SDoc -> SDoc) -> ([Name] -> SDoc) -> [Name] -> SDoc
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . (Name -> SDoc) -> [Name] -> SDoc
    forall a. (a -> SDoc) -> [a] -> SDoc
    pprWithCommas Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr)
                     ] SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Char -> SDoc
    forall doc. IsLine doc => Char -> doc
    char Char
    '}')
        where
          ppr_elt :: Name -> SDoc
    ppr_elt Name
    name = SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    parens (OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (Name -> OccName
    nameOccName Name
    name)) SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name
                         -- So we can see if the keys line up correctly

    emptyLocalRdrEnv :: LocalRdrEnv
    emptyLocalRdrEnv :: LocalRdrEnv
    emptyLocalRdrEnv = LRE { lre_env :: OccEnv Name
    lre_env = OccEnv Name
    forall a. OccEnv a
    emptyOccEnv
                           , lre_in_scope :: NameSet
    lre_in_scope = NameSet
    emptyNameSet }

    extendLocalRdrEnv :: LocalRdrEnv -> Name -> LocalRdrEnv
    -- See Note [LocalRdrEnv]
    extendLocalRdrEnv :: LocalRdrEnv -> Name -> LocalRdrEnv
    extendLocalRdrEnv lre :: LocalRdrEnv
    lre@(LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env, lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns }) Name
    name
      = LocalRdrEnv
    lre { lre_env      = extendOccEnv env (nameOccName name) name
            , lre_in_scope = extendNameSet ns name }

    extendLocalRdrEnvList :: LocalRdrEnv -> [Name] -> LocalRdrEnv
    -- See Note [LocalRdrEnv]
    extendLocalRdrEnvList :: LocalRdrEnv -> [Name] -> LocalRdrEnv
    extendLocalRdrEnvList lre :: LocalRdrEnv
    lre@(LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env, lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns }) [Name]
    names
      = LocalRdrEnv
    lre { lre_env = extendOccEnvList env [(nameOccName n, n) | n <- names]
            , lre_in_scope = extendNameSetList ns names }

    lookupLocalRdrEnv :: LocalRdrEnv -> RdrName -> Maybe Name
    lookupLocalRdrEnv :: LocalRdrEnv -> RdrName -> Maybe Name
    lookupLocalRdrEnv (LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env, lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns }) RdrName
    rdr
      | Unqual OccName
    occ <- RdrName
    rdr
      = OccEnv Name -> OccName -> Maybe Name
    forall a. OccEnv a -> OccName -> Maybe a
    lookupOccEnv OccEnv Name
    env OccName
    occ

      -- See Note [Local bindings with Exact Names]
      | Exact Name
    name <- RdrName
    rdr
      , Name
    name Name -> NameSet -> Bool
    `elemNameSet` NameSet
    ns
      = Name -> Maybe Name
    forall a. a -> Maybe a
    Just Name
    name

      | Bool
    otherwise
      = Maybe Name
    forall a. Maybe a
    Nothing

    lookupLocalRdrOcc :: LocalRdrEnv -> OccName -> Maybe Name
    lookupLocalRdrOcc :: LocalRdrEnv -> OccName -> Maybe Name
    lookupLocalRdrOcc (LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env }) OccName
    occ = OccEnv Name -> OccName -> Maybe Name
    forall a. OccEnv a -> OccName -> Maybe a
    lookupOccEnv OccEnv Name
    env OccName
    occ

    elemLocalRdrEnv :: RdrName -> LocalRdrEnv -> Bool
    elemLocalRdrEnv :: RdrName -> LocalRdrEnv -> Bool
    elemLocalRdrEnv RdrName
    rdr_name (LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env, lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns })
      = case RdrName
    rdr_name of
          Unqual OccName
    occ -> OccName
    occ  OccName -> OccEnv Name -> Bool
    forall a. OccName -> OccEnv a -> Bool
    `elemOccEnv` OccEnv Name
    env
          Exact Name
    name -> Name
    name Name -> NameSet -> Bool
    `elemNameSet` NameSet
    ns  -- See Note [Local bindings with Exact Names]
          Qual {} -> Bool
    False
          Orig {} -> Bool
    False

    localRdrEnvElts :: LocalRdrEnv -> [Name]
    localRdrEnvElts :: LocalRdrEnv -> [Name]
    localRdrEnvElts (LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env }) = OccEnv Name -> [Name]
    forall a. OccEnv a -> [a]
    nonDetOccEnvElts OccEnv Name
    env

    inLocalRdrEnvScope :: Name -> LocalRdrEnv -> Bool
    -- This is the point of the NameSet
    inLocalRdrEnvScope :: Name -> LocalRdrEnv -> Bool
    inLocalRdrEnvScope Name
    name (LRE { lre_in_scope :: LocalRdrEnv -> NameSet
    lre_in_scope = NameSet
    ns }) = Name
    name Name -> NameSet -> Bool
    `elemNameSet` NameSet
    ns

    minusLocalRdrEnv :: LocalRdrEnv -> OccEnv a -> LocalRdrEnv
    minusLocalRdrEnv :: forall a. LocalRdrEnv -> OccEnv a -> LocalRdrEnv
    minusLocalRdrEnv lre :: LocalRdrEnv
    lre@(LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env }) OccEnv a
    occs
      = LocalRdrEnv
    lre { lre_env = minusOccEnv env occs }

    minusLocalRdrEnvList :: LocalRdrEnv -> [OccName] -> LocalRdrEnv
    minusLocalRdrEnvList :: LocalRdrEnv -> [OccName] -> LocalRdrEnv
    minusLocalRdrEnvList lre :: LocalRdrEnv
    lre@(LRE { lre_env :: LocalRdrEnv -> OccEnv Name
    lre_env = OccEnv Name
    env }) [OccName]
    occs
      = LocalRdrEnv
    lre { lre_env = delListFromOccEnv env occs }

    {-
    Note [Local bindings with Exact Names]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    With Template Haskell we can make local bindings that have Exact Names.
    Computing shadowing etc may use elemLocalRdrEnv (at least it certainly
    does so in GHC.Rename.HsType.bindHsQTyVars), so for an Exact Name we must consult
    the in-scope-name-set.

    ************************************************************************
    *                                                                      *
                            GlobalRdrEnv
    *                                                                      *
    ************************************************************************
    -}

    -- | Global Reader Environment
    type GlobalRdrEnv = GlobalRdrEnvX GREInfo
    -- ^ Keyed by 'OccName'; when looking up a qualified name
    -- we look up the 'OccName' part, and then check the 'Provenance'
    -- to see if the appropriate qualification is valid.  This
    -- saves routinely doubling the size of the env by adding both
    -- qualified and unqualified names to the domain.
    --
    -- The list in the codomain is required because there may be name clashes
    -- These only get reported on lookup, not on construction
    --
    -- INVARIANT 1: All the members of the list have distinct
    --              'gre_name' fields; that is, no duplicate Names
    --
    -- INVARIANT 2: Imported provenance => Name is an ExternalName
    --              However LocalDefs can have an InternalName.  This
    --              happens only when type-checking a [d| ... |] Template
    --              Haskell quotation; see this note in GHC.Rename.Names
    --              Note [Top-level Names in Template Haskell decl quotes]
    --
    -- INVARIANT 3: If the GlobalRdrEnv maps [occ -> gre], then
    --                 greOccName gre = occ

    -- | A 'GlobalRdrEnv' in which the 'GlobalRdrElt's don't have any 'GREInfo'
    -- attached to them. This is useful to avoid space leaks, see Note [IfGlobalRdrEnv].
    type IfGlobalRdrEnv = GlobalRdrEnvX ()

    -- | Parametrises 'GlobalRdrEnv' over the presence or absence of 'GREInfo'.
    --
    -- See Note [IfGlobalRdrEnv].
    type GlobalRdrEnvX info = OccEnv [GlobalRdrEltX info]

    -- | Global Reader Element
    --
    -- Something in scope in the renamer; usually a member of the 'GlobalRdrEnv'.
    -- See Note [GlobalRdrElt provenance].

    type GlobalRdrElt   = GlobalRdrEltX GREInfo

    -- | A 'GlobalRdrElt' in which we stripped out the 'GREInfo' field,
    -- in order to avoid space leaks.
    --
    -- See Note [IfGlobalRdrEnv].
    type IfGlobalRdrElt = GlobalRdrEltX ()

    -- | Global Reader Element
    --
    -- Something in scope in the renamer; usually a member of the 'GlobalRdrEnv'.
    -- See Note [GlobalRdrElt provenance].
    --
    -- Why do we parametrise over the 'gre_info' field? See Note [IfGlobalRdrEnv].
    data GlobalRdrEltX info
      = GRE { forall info. GlobalRdrEltX info -> Name
    gre_name :: !Name
            , forall info. GlobalRdrEltX info -> Parent
    gre_par  :: !Parent            -- ^ See Note [Parents]
            , forall info. GlobalRdrEltX info -> Bool
    gre_lcl  :: !Bool              -- ^ True <=> the thing was defined locally
            , forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp  :: !(Bag ImportSpec)  -- ^ In scope through these imports
      -- See Note [GlobalRdrElt provenance] for the relation between gre_lcl and gre_imp.

            , forall info. GlobalRdrEltX info -> info
    gre_info :: info
                -- ^ Information the renamer knows about this particular 'Name'.
                --
                -- Careful about forcing this field! Forcing it can trigger
                -- the loading of interface files.
                --
                -- Note [Retrieving the GREInfo from interfaces] in GHC.Types.GREInfo.
        } deriving (Typeable (GlobalRdrEltX info)
    Typeable (GlobalRdrEltX info) =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g)
     -> GlobalRdrEltX info
     -> c (GlobalRdrEltX info))
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c (GlobalRdrEltX info))
    -> (GlobalRdrEltX info -> Constr)
    -> (GlobalRdrEltX info -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c (GlobalRdrEltX info)))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e))
        -> Maybe (c (GlobalRdrEltX info)))
    -> ((forall b. Data b => b -> b)
        -> GlobalRdrEltX info -> GlobalRdrEltX info)
    -> (forall r r'.
        (r -> r' -> r)
        -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r)
    -> (forall r r'.
        (r' -> r -> r)
        -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r)
    -> (forall u.
        (forall d. Data d => d -> u) -> GlobalRdrEltX info -> [u])
    -> (forall u.
        Int -> (forall d. Data d => d -> u) -> GlobalRdrEltX info -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d)
        -> GlobalRdrEltX info -> m (GlobalRdrEltX info))
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d)
        -> GlobalRdrEltX info -> m (GlobalRdrEltX info))
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d)
        -> GlobalRdrEltX info -> m (GlobalRdrEltX info))
    -> Data (GlobalRdrEltX info)
    GlobalRdrEltX info -> Constr
    GlobalRdrEltX info -> DataType
    (forall b. Data b => b -> b)
    -> GlobalRdrEltX info -> GlobalRdrEltX info
    forall info. Data info => Typeable (GlobalRdrEltX info)
    forall info. Data info => GlobalRdrEltX info -> Constr
    forall info. Data info => GlobalRdrEltX info -> DataType
    forall info.
    Data info =>
    (forall b. Data b => b -> b)
    -> GlobalRdrEltX info -> GlobalRdrEltX info
    forall info u.
    Data info =>
    Int -> (forall d. Data d => d -> u) -> GlobalRdrEltX info -> u
    forall info u.
    Data info =>
    (forall d. Data d => d -> u) -> GlobalRdrEltX info -> [u]
    forall info r r'.
    Data info =>
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    forall info r r'.
    Data info =>
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    forall info (m :: * -> *).
    (Data info, Monad m) =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    forall info (m :: * -> *).
    (Data info, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    forall info (c :: * -> *).
    Data info =>
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (GlobalRdrEltX info)
    forall info (c :: * -> *).
    Data info =>
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g)
    -> GlobalRdrEltX info
    -> c (GlobalRdrEltX info)
    forall info (t :: * -> *) (c :: * -> *).
    (Data info, Typeable t) =>
    (forall d. Data d => c (t d)) -> Maybe (c (GlobalRdrEltX info))
    forall info (t :: * -> * -> *) (c :: * -> *).
    (Data info, Typeable t) =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (GlobalRdrEltX info))
    forall a.
    Typeable a =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> a -> c a)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
    -> (a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall r r'.
        (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u.
    Int -> (forall d. Data d => d -> u) -> GlobalRdrEltX info -> u
    forall u. (forall d. Data d => d -> u) -> GlobalRdrEltX info -> [u]
    forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (GlobalRdrEltX info)
    forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g)
    -> GlobalRdrEltX info
    -> c (GlobalRdrEltX info)
    forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c (GlobalRdrEltX info))
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (GlobalRdrEltX info))
    $cgfoldl :: forall info (c :: * -> *).
    Data info =>
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g)
    -> GlobalRdrEltX info
    -> c (GlobalRdrEltX info)
    gfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g)
    -> GlobalRdrEltX info
    -> c (GlobalRdrEltX info)
    $cgunfold :: forall info (c :: * -> *).
    Data info =>
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (GlobalRdrEltX info)
    gunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c (GlobalRdrEltX info)
    $ctoConstr :: forall info. Data info => GlobalRdrEltX info -> Constr
    toConstr :: GlobalRdrEltX info -> Constr
    $cdataTypeOf :: forall info. Data info => GlobalRdrEltX info -> DataType
    dataTypeOf :: GlobalRdrEltX info -> DataType
    $cdataCast1 :: forall info (t :: * -> *) (c :: * -> *).
    (Data info, Typeable t) =>
    (forall d. Data d => c (t d)) -> Maybe (c (GlobalRdrEltX info))
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c (GlobalRdrEltX info))
    $cdataCast2 :: forall info (t :: * -> * -> *) (c :: * -> *).
    (Data info, Typeable t) =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (GlobalRdrEltX info))
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c (GlobalRdrEltX info))
    $cgmapT :: forall info.
    Data info =>
    (forall b. Data b => b -> b)
    -> GlobalRdrEltX info -> GlobalRdrEltX info
    gmapT :: (forall b. Data b => b -> b)
    -> GlobalRdrEltX info -> GlobalRdrEltX info
    $cgmapQl :: forall info r r'.
    Data info =>
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    gmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    $cgmapQr :: forall info r r'.
    Data info =>
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    gmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> GlobalRdrEltX info -> r
    $cgmapQ :: forall info u.
    Data info =>
    (forall d. Data d => d -> u) -> GlobalRdrEltX info -> [u]
    gmapQ :: forall u. (forall d. Data d => d -> u) -> GlobalRdrEltX info -> [u]
    $cgmapQi :: forall info u.
    Data info =>
    Int -> (forall d. Data d => d -> u) -> GlobalRdrEltX info -> u
    gmapQi :: forall u.
    Int -> (forall d. Data d => d -> u) -> GlobalRdrEltX info -> u
    $cgmapM :: forall info (m :: * -> *).
    (Data info, Monad m) =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    gmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    $cgmapMp :: forall info (m :: * -> *).
    (Data info, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    gmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    $cgmapMo :: forall info (m :: * -> *).
    (Data info, MonadPlus m) =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    gmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d)
    -> GlobalRdrEltX info -> m (GlobalRdrEltX info)
    Data)

    instance NFData a => NFData (GlobalRdrEltX a) where
      rnf :: GlobalRdrEltX a -> ()
    rnf (GRE Name
    name Parent
    par Bool
    _ Bag ImportSpec
    imp a
    info) = Name -> ()
    forall a. NFData a => a -> ()
    rnf Name
    name () -> () -> ()
    forall a b. a -> b -> b
    `seq` Parent -> ()
    forall a. NFData a => a -> ()
    rnf Parent
    par () -> () -> ()
    forall a b. a -> b -> b
    `seq` Bag ImportSpec -> ()
    forall a. NFData a => a -> ()
    rnf Bag ImportSpec
    imp () -> () -> ()
    forall a b. a -> b -> b
    `seq` a -> ()
    forall a. NFData a => a -> ()
    rnf a
    info

    {- Note [IfGlobalRdrEnv]
    ~~~~~~~~~~~~~~~~~~~~~~~~
    Information pertinent to the renamer about a 'Name' is stored in the fields of
    'GlobalRdrElt'. The 'gre_info' field, described in Note [GREInfo] in GHC.Types.GREInfo,
    is a bit special: as Note [Retrieving the GREInfo from interfaces] in GHC.Types.GREInfo
    describes, for imported 'Name's it is usually obtained by a look up in a type environment,
    and forcing can cause the interface file for the module defining the 'Name' to be
    loaded. As described in Note [Forcing GREInfo] in GHC.Types.GREInfo, keeping it
    a thunk can cause space leaks, while forcing it can cause extra work to be done.
    So it's best to discard it when we don't need it, for example when we are about
    to store it in a 'ModIface'.

    We thus parametrise 'GlobalRdrElt' (and 'GlobalRdrEnv') over the presence or
    absence of the 'GREInfo' field.

      - When we are about to stash the 'GlobalRdrElt' in a long-lived data structure,
        e.g. a 'ModIface', we force it by setting all the 'GREInfo' fields to '()'.
        See 'forceGlobalRdrEnv'.
      - To go back the other way, we use 'hydrateGlobalRdrEnv', which sets the
        'gre_info' fields back to lazy lookups.

    This parametrisation also helps ensure that we don't accidentally force the
    GREInfo field (which can cause unnecessary loading of interface files).
    In particular, the 'lookupGRE' function is statically guaranteed to not consult
    the 'GREInfo' field when using 'SameNameSpace', which is important
    as we sometimes need to use this function with an 'IfaceGlobalRdrEnv' in which
    the 'GREInfo' fields have been stripped.
    -}

    -- | A 'FieldGlobalRdrElt' is a 'GlobalRdrElt'
    -- in which the 'gre_info' field is 'IAmRecField'.
    type FieldGlobalRdrElt = GlobalRdrElt

    greName :: GlobalRdrEltX info -> Name
    greName :: forall info. GlobalRdrEltX info -> Name
    greName = GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    gre_name

    greNameSpace :: GlobalRdrEltX info -> NameSpace
    greNameSpace :: forall info. GlobalRdrEltX info -> NameSpace
    greNameSpace = Name -> NameSpace
    nameNameSpace (Name -> NameSpace)
    -> (GlobalRdrEltX info -> Name) -> GlobalRdrEltX info -> NameSpace
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName

    greParent :: GlobalRdrEltX info -> Parent
    greParent :: forall info. GlobalRdrEltX info -> Parent
    greParent = GlobalRdrEltX info -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par

    greInfo :: GlobalRdrElt -> GREInfo
    greInfo :: GlobalRdrElt -> GREInfo
    greInfo = GlobalRdrElt -> GREInfo
    forall info. GlobalRdrEltX info -> info
    gre_info

    -- | See Note [Parents]
    data Parent = NoParent
                | ParentIs  { Parent -> Name
    par_is :: !Name }
                deriving (Parent -> Parent -> Bool
    (Parent -> Parent -> Bool)
    -> (Parent -> Parent -> Bool) -> Eq Parent
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: Parent -> Parent -> Bool
    == :: Parent -> Parent -> Bool
    $c/= :: Parent -> Parent -> Bool
    /= :: Parent -> Parent -> Bool
    Eq, Typeable Parent
    Typeable Parent =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> Parent -> c Parent)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c Parent)
    -> (Parent -> Constr)
    -> (Parent -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c Parent))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Parent))
    -> ((forall b. Data b => b -> b) -> Parent -> Parent)
    -> (forall r r'.
        (r -> r' -> r)
        -> r -> (forall d. Data d => d -> r') -> Parent -> r)
    -> (forall r r'.
        (r' -> r -> r)
        -> r -> (forall d. Data d => d -> r') -> Parent -> r)
    -> (forall u. (forall d. Data d => d -> u) -> Parent -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> Parent -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> Parent -> m Parent)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> Parent -> m Parent)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> Parent -> m Parent)
    -> Data Parent
    Parent -> Constr
    Parent -> DataType
    (forall b. Data b => b -> b) -> Parent -> Parent
    forall a.
    Typeable a =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> a -> c a)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
    -> (a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall r r'.
        (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> Parent -> u
    forall u. (forall d. Data d => d -> u) -> Parent -> [u]
    forall r r'.
    (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    forall r r'.
    (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c Parent
    forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> Parent -> c Parent
    forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c Parent)
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Parent)
    $cgfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> Parent -> c Parent
    gfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> Parent -> c Parent
    $cgunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c Parent
    gunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c Parent
    $ctoConstr :: Parent -> Constr
    toConstr :: Parent -> Constr
    $cdataTypeOf :: Parent -> DataType
    dataTypeOf :: Parent -> DataType
    $cdataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c Parent)
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c Parent)
    $cdataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Parent)
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Parent)
    $cgmapT :: (forall b. Data b => b -> b) -> Parent -> Parent
    gmapT :: (forall b. Data b => b -> b) -> Parent -> Parent
    $cgmapQl :: forall r r'.
    (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    gmapQl :: forall r r'.
    (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    $cgmapQr :: forall r r'.
    (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    gmapQr :: forall r r'.
    (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Parent -> r
    $cgmapQ :: forall u. (forall d. Data d => d -> u) -> Parent -> [u]
    gmapQ :: forall u. (forall d. Data d => d -> u) -> Parent -> [u]
    $cgmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> Parent -> u
    gmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> Parent -> u
    $cgmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    gmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    $cgmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    gmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    $cgmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    gmapMo :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> Parent -> m Parent
    Data)

    instance Outputable Parent where
       ppr :: Parent -> SDoc
    ppr Parent
    NoParent        = SDoc
    forall doc. IsOutput doc => doc
    empty
       ppr (ParentIs Name
    n)    = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "parent:" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    n

    instance NFData Parent where
      rnf :: Parent -> ()
    rnf Parent
    NoParent = ()
      rnf (ParentIs Name
    n) = Name -> ()
    forall a. NFData a => a -> ()
    rnf Name
    n

    plusParent :: Parent -> Parent -> Parent
    -- See Note [Combining parents]
    plusParent :: Parent -> Parent -> Parent
    plusParent p1 :: Parent
    p1@(ParentIs Name
    _)    Parent
    p2 = Parent -> Parent -> Parent
    hasParent Parent
    p1 Parent
    p2
    plusParent Parent
    p1 p2 :: Parent
    p2@(ParentIs Name
    _)    = Parent -> Parent -> Parent
    hasParent Parent
    p2 Parent
    p1
    plusParent Parent
    NoParent Parent
    NoParent     = Parent
    NoParent

    hasParent :: Parent -> Parent -> Parent
    #if defined(DEBUG)
    hasParent p NoParent = p
    hasParent p p'
      | p /= p' = pprPanic "hasParent" (ppr p <+> ppr p')  -- Parents should agree
    #endif
    hasParent :: Parent -> Parent -> Parent
    hasParent Parent
    p Parent
    _  = Parent
    p

    {- Note [GlobalRdrElt provenance]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    The gre_lcl and gre_imp fields of a GlobalRdrElt describe its "provenance",
    i.e. how the Name came to be in scope.  It can be in scope in one of the following
    three ways:

      A. The Name was locally bound, in the current module.
         gre_lcl = True

         The renamer adds this Name to the GlobalRdrEnv after renaming the binding.
         See the calls to "extendGlobalRdrEnvRn" in GHC.Rename.Module.rnSrcDecls.

      B. The Name was imported
         gre_imp = Just imps <=> brought into scope by the imports "imps"

         The renamer adds this Name to the GlobalRdrEnv after processing the imports.
         See GHC.Rename.Names.filterImports and GHC.Tc.Module.tcRnImports.

      C. We followed an exact reference (i.e. an Exact or Orig RdrName)
         gre_lcl = False, gre_imp = Nothing

         In this case, we directly fetch a Name and its GREInfo from direct reference.
         We don't add it to the GlobalRdrEnv. See "GHC.Rename.Env.lookupExactOrOrig".

    It is just about possible to have *both* gre_lcl = True and gre_imp = Just imps.
    This can happen with module loops: a Name is defined locally in A, and also
    brought into scope by importing a module that SOURCE-imported A.

    Example (#7672):

     A.hs-boot   module A where
                   data T

     B.hs        module B(Decl.T) where
                   import {-# SOURCE #-} qualified A as Decl

     A.hs        module A where
                   import qualified B
                   data T = Z | S B.T

    In A.hs, 'T' is locally bound, *and* imported as B.T.

    Note [Parents]
    ~~~~~~~~~~~~~~~~~
    The children of a Name are the things that are abbreviated by the ".." notation
    in export lists.

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      Parent           Children
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      data T           Data constructors
                       Record-field ids

      data family T    Data constructors and record-field ids
                       of all visible data instances of T

      class C          Class operations
                       Associated type constructors

    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      Constructor      Meaning
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      NoParent         Not bundled with a type constructor.
      ParentIs n       Bundled with the type constructor corresponding to n.

    Pattern synonym constructors (and their record fields, if any) are unusual:
    their gre_par is NoParent in the module in which they are defined.  However, a
    pattern synonym can be bundled with a type constructor on export, in which case
    whenever the pattern synonym is imported the gre_par will be ParentIs.

    Thus the gre_name and gre_par fields are independent, because a normal datatype
    introduces FieldGlobalRdrElts using ParentIs, but a record pattern synonym can
    introduce FieldGlobalRdrElts that use NoParent. (In the past we represented
    fields using an additional constructor of the Parent type, which could not
    adequately represent this situation.) See also
    Note [Representing pattern synonym fields in AvailInfo] in GHC.Types.Avail.

    Note [Combining parents]
    ~~~~~~~~~~~~~~~~~~~~~~~~
    With an associated type we might have
       module M where
         class C a where
           data T a
           op :: T a -> a
         instance C Int where
           data T Int = TInt
         instance C Bool where
           data T Bool = TBool

    Then:   C is the parent of T
            T is the parent of TInt and TBool
    So: in an export list
        C(..) is short for C( op, T )
        T(..) is short for T( TInt, TBool )

    Module M exports everything, so its exports will be
       AvailTC C [C,T,op]
       AvailTC T [T,TInt,TBool]
    On import we convert to GlobalRdrElt and then combine
    those.  For T that will mean we have
      one GRE with Parent C
      one GRE with NoParent
    That's why plusParent picks the "best" case.
    -}

    mkGRE :: (Name -> Maybe ImportSpec) -> GREInfo -> Parent -> Name -> GlobalRdrElt
    mkGRE :: (Name -> Maybe ImportSpec)
    -> GREInfo -> Parent -> Name -> GlobalRdrElt
    mkGRE Name -> Maybe ImportSpec
    prov_fn GREInfo
    info Parent
    par Name
    n =
      case Name -> Maybe ImportSpec
    prov_fn Name
    n of
          -- Nothing => bound locally
          -- Just is => imported from 'is'
        Maybe ImportSpec
    Nothing -> GRE { gre_name :: Name
    gre_name = Name
    n, gre_par :: Parent
    gre_par = Parent
    par
                       , gre_lcl :: Bool
    gre_lcl = Bool
    True, gre_imp :: Bag ImportSpec
    gre_imp = Bag ImportSpec
    forall a. Bag a
    emptyBag
                       , gre_info :: GREInfo
    gre_info = GREInfo
    info }
        Just ImportSpec
    is -> GRE { gre_name :: Name
    gre_name = Name
    n, gre_par :: Parent
    gre_par = Parent
    par
                       , gre_lcl :: Bool
    gre_lcl = Bool
    False, gre_imp :: Bag ImportSpec
    gre_imp = ImportSpec -> Bag ImportSpec
    forall a. a -> Bag a
    unitBag ImportSpec
    is
                       , gre_info :: GREInfo
    gre_info = GREInfo
    info }

    mkExactGRE :: Name -> GREInfo -> GlobalRdrElt
    mkExactGRE :: Name -> GREInfo -> GlobalRdrElt
    mkExactGRE Name
    nm GREInfo
    info =
      GRE { gre_name :: Name
    gre_name = Name
    nm, gre_par :: Parent
    gre_par = Parent
    NoParent
          , gre_lcl :: Bool
    gre_lcl = Bool
    False, gre_imp :: Bag ImportSpec
    gre_imp = Bag ImportSpec
    forall a. Bag a
    emptyBag
          , gre_info :: GREInfo
    gre_info = GREInfo
    info }

    mkLocalGRE :: GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE :: GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE = (Name -> Maybe ImportSpec)
    -> GREInfo -> Parent -> Name -> GlobalRdrElt
    mkGRE (Maybe ImportSpec -> Name -> Maybe ImportSpec
    forall a b. a -> b -> a
    const Maybe ImportSpec
    forall a. Maybe a
    Nothing)

    mkLocalVanillaGRE :: Parent -> Name -> GlobalRdrElt
    mkLocalVanillaGRE :: Parent -> Name -> GlobalRdrElt
    mkLocalVanillaGRE = GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE GREInfo
    Vanilla

    -- | Create a local 'GlobalRdrElt' for a 'TyCon'.
    mkLocalTyConGRE :: TyConFlavour Name
                  -> Name
                  -> GlobalRdrElt
    mkLocalTyConGRE :: TyConFlavour Name -> Name -> GlobalRdrElt
    mkLocalTyConGRE TyConFlavour Name
    flav Name
    nm = GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE (TyConFlavour Name -> GREInfo
    IAmTyCon TyConFlavour Name
    flav) Parent
    par Name
    nm
      where
        par :: Parent
    par = case TyConFlavour Name -> Maybe Name
    forall tc. TyConFlavour tc -> Maybe tc
    tyConFlavourAssoc_maybe TyConFlavour Name
    flav of
          Maybe Name
    Nothing -> Parent
    NoParent
          Just Name
    p  -> Name -> Parent
    ParentIs Name
    p

    mkLocalConLikeGRE :: Parent -> (ConLikeName, ConInfo) -> GlobalRdrElt
    mkLocalConLikeGRE :: Parent -> (ConLikeName, ConInfo) -> GlobalRdrElt
    mkLocalConLikeGRE Parent
    p (ConLikeName
    con_nm, ConInfo
    con_info) =
      GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE (ConInfo -> GREInfo
    IAmConLike ConInfo
    con_info) Parent
    p (ConLikeName -> Name
    conLikeName_Name ConLikeName
    con_nm )

    mkLocalFieldGREs :: Parent -> [(ConLikeName, ConInfo)] -> [GlobalRdrElt]
    mkLocalFieldGREs :: Parent -> [(ConLikeName, ConInfo)] -> [GlobalRdrElt]
    mkLocalFieldGREs Parent
    p [(ConLikeName, ConInfo)]
    cons =
      [ GREInfo -> Parent -> Name -> GlobalRdrElt
    mkLocalGRE (RecFieldInfo -> GREInfo
    IAmRecField RecFieldInfo
    fld_info) Parent
    p Name
    fld_nm
      | (S.Arg Name
    fld_nm FieldLabel
    fl, UniqSet ConLikeName
    fl_cons) <- [(Arg Name FieldLabel, UniqSet ConLikeName)]
    flds
      , let fld_info :: RecFieldInfo
    fld_info = RecFieldInfo { recFieldLabel :: FieldLabel
    recFieldLabel = FieldLabel
    fl
                                    , recFieldCons :: UniqSet ConLikeName
    recFieldCons  = UniqSet ConLikeName
    fl_cons } ]
      where
        -- We are given a map taking a constructor to its fields, but we want
        -- a map taking a field to the constructors which have it.
        -- We thus need to convert [(Con, [Field])] into [(Field, [Con])].
        flds :: [(Arg Name FieldLabel, UniqSet ConLikeName)]
    flds = Map (Arg Name FieldLabel) (UniqSet ConLikeName)
    -> [(Arg Name FieldLabel, UniqSet ConLikeName)]
    forall k a. Map k a -> [(k, a)]
    Map.toList
             (Map (Arg Name FieldLabel) (UniqSet ConLikeName)
     -> [(Arg Name FieldLabel, UniqSet ConLikeName)])
    -> Map (Arg Name FieldLabel) (UniqSet ConLikeName)
    -> [(Arg Name FieldLabel, UniqSet ConLikeName)]
    forall a b. (a -> b) -> a -> b
    $ (UniqSet ConLikeName -> UniqSet ConLikeName -> UniqSet ConLikeName)
    -> [(Arg Name FieldLabel, UniqSet ConLikeName)]
    -> Map (Arg Name FieldLabel) (UniqSet ConLikeName)
    forall k a. Ord k => (a -> a -> a) -> [(k, a)] -> Map k a
    Map.fromListWith UniqSet ConLikeName -> UniqSet ConLikeName -> UniqSet ConLikeName
    forall a. UniqSet a -> UniqSet a -> UniqSet a
    unionUniqSets
             [ (Name -> FieldLabel -> Arg Name FieldLabel
    forall a b. a -> b -> Arg a b
    S.Arg (FieldLabel -> Name
    flSelector FieldLabel
    fl) FieldLabel
    fl, ConLikeName -> UniqSet ConLikeName
    forall a. Uniquable a => a -> UniqSet a
    unitUniqSet ConLikeName
    con)
             | (ConLikeName
    con, ConInfo
    con_info) <- [(ConLikeName, ConInfo)]
    cons
             , ConHasRecordFields NonEmpty FieldLabel
    fls <- [ConInfo
    con_info]
             , FieldLabel
    fl <- NonEmpty FieldLabel -> [FieldLabel]
    forall a. NonEmpty a -> [a]
    NE.toList NonEmpty FieldLabel
    fls ]

    instance HasOccName (GlobalRdrEltX info) where
      occName :: GlobalRdrEltX info -> OccName
    occName = GlobalRdrEltX info -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName

    greOccName :: GlobalRdrEltX info -> OccName
    greOccName :: forall info. GlobalRdrEltX info -> OccName
    greOccName ( GRE { gre_name :: forall info. GlobalRdrEltX info -> Name
    gre_name = Name
    nm } ) = Name -> OccName
    nameOccName Name
    nm

    -- | The SrcSpan of the name pointed to by the GRE.
    greDefinitionSrcSpan :: GlobalRdrEltX info -> SrcSpan
    greDefinitionSrcSpan :: forall info. GlobalRdrEltX info -> SrcSpan
    greDefinitionSrcSpan = Name -> SrcSpan
    nameSrcSpan (Name -> SrcSpan)
    -> (GlobalRdrEltX info -> Name) -> GlobalRdrEltX info -> SrcSpan
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName

    -- | The module in which the name pointed to by the GRE is defined.
    greDefinitionModule :: GlobalRdrEltX info -> Maybe Module
    greDefinitionModule :: forall info. GlobalRdrEltX info -> Maybe Module
    greDefinitionModule = Name -> Maybe Module
    nameModule_maybe (Name -> Maybe Module)
    -> (GlobalRdrEltX info -> Name)
    -> GlobalRdrEltX info
    -> Maybe Module
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName

    greQualModName :: Outputable info => GlobalRdrEltX info -> ModuleName
    -- Get a suitable module qualifier for the GRE
    -- (used in mkPrintUnqualified)
    -- Precondition: the gre_name is always External
    greQualModName :: forall info. Outputable info => GlobalRdrEltX info -> ModuleName
    greQualModName gre :: GlobalRdrEltX info
    gre@(GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
     | Bool
    lcl, Just Module
    mod <- GlobalRdrEltX info -> Maybe Module
    forall info. GlobalRdrEltX info -> Maybe Module
    greDefinitionModule GlobalRdrEltX info
    gre = Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName Module
    mod
     | Just ImportSpec
    is <- Bag ImportSpec -> Maybe ImportSpec
    forall a. Bag a -> Maybe a
    headMaybe Bag ImportSpec
    iss                 = ImpDeclSpec -> ModuleName
    is_as (ImportSpec -> ImpDeclSpec
    is_decl ImportSpec
    is)
     | Bool
    otherwise                                = String -> SDoc -> ModuleName
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "greQualModName" (GlobalRdrEltX info -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GlobalRdrEltX info
    gre)

    greRdrNames :: GlobalRdrEltX info -> [RdrName]
    greRdrNames :: forall info. GlobalRdrEltX info -> [RdrName]
    greRdrNames gre :: GlobalRdrEltX info
    gre@GRE{ gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss }
      = Bag RdrName -> [RdrName]
    forall a. Bag a -> [a]
    bagToList (Bag RdrName -> [RdrName]) -> Bag RdrName -> [RdrName]
    forall a b. (a -> b) -> a -> b
    $ (if Bool
    lcl then RdrName -> Bag RdrName
    forall a. a -> Bag a
    unitBag RdrName
    unqual else Bag RdrName
    forall a. Bag a
    emptyBag) Bag RdrName -> Bag RdrName -> Bag RdrName
    forall a. Bag a -> Bag a -> Bag a
    `unionBags` (ImpDeclSpec -> Bag RdrName) -> Bag ImpDeclSpec -> Bag RdrName
    forall a b. (a -> Bag b) -> Bag a -> Bag b
    concatMapBag ImpDeclSpec -> Bag RdrName
    do_spec ((ImportSpec -> ImpDeclSpec) -> Bag ImportSpec -> Bag ImpDeclSpec
    forall a b. (a -> b) -> Bag a -> Bag b
    mapBag ImportSpec -> ImpDeclSpec
    is_decl Bag ImportSpec
    iss)
      where
        occ :: OccName
    occ    = GlobalRdrEltX info -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName GlobalRdrEltX info
    gre
        unqual :: RdrName
    unqual = OccName -> RdrName
    Unqual OccName
    occ
        do_spec :: ImpDeclSpec -> Bag RdrName
    do_spec ImpDeclSpec
    decl_spec
            | ImpDeclSpec -> Bool
    is_qual ImpDeclSpec
    decl_spec = RdrName -> Bag RdrName
    forall a. a -> Bag a
    unitBag RdrName
    qual
            | Bool
    otherwise         = [RdrName] -> Bag RdrName
    forall a. [a] -> Bag a
    listToBag [RdrName
    unqual,RdrName
    qual]
            where qual :: RdrName
    qual = ModuleName -> OccName -> RdrName
    Qual (ImpDeclSpec -> ModuleName
    is_as ImpDeclSpec
    decl_spec) OccName
    occ

    -- the SrcSpan that pprNameProvenance prints out depends on whether
    -- the Name is defined locally or not: for a local definition the
    -- definition site is used, otherwise the location of the import
    -- declaration.  We want to sort the export locations in
    -- exportClashErr by this SrcSpan, we need to extract it:
    greSrcSpan :: Outputable info => GlobalRdrEltX info -> SrcSpan
    greSrcSpan :: forall info. Outputable info => GlobalRdrEltX info -> SrcSpan
    greSrcSpan gre :: GlobalRdrEltX info
    gre@(GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss } )
      | Bool
    lcl           = GlobalRdrEltX info -> SrcSpan
    forall info. GlobalRdrEltX info -> SrcSpan
    greDefinitionSrcSpan GlobalRdrEltX info
    gre
      | Just ImportSpec
    is <- Bag ImportSpec -> Maybe ImportSpec
    forall a. Bag a -> Maybe a
    headMaybe Bag ImportSpec
    iss = ImpDeclSpec -> SrcSpan
    is_dloc (ImportSpec -> ImpDeclSpec
    is_decl ImportSpec
    is)
      | Bool
    otherwise     = String -> SDoc -> SrcSpan
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "greSrcSpan" (GlobalRdrEltX info -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GlobalRdrEltX info
    gre)

    mkParent :: Name -> AvailInfo -> Parent
    mkParent :: Name -> AvailInfo -> Parent
    mkParent Name
    _ (Avail Name
    _)                 = Parent
    NoParent
    mkParent Name
    n (AvailTC Name
    m [Name]
    _) | Name
    n Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    == Name
    m    = Parent
    NoParent
                             | Bool
    otherwise = Name -> Parent
    ParentIs Name
    m

    availParent :: AvailInfo -> Parent
    availParent :: AvailInfo -> Parent
    availParent (AvailTC Name
    m [Name]
    _) = Name -> Parent
    ParentIs Name
    m
    availParent (Avail {})    = Parent
    NoParent

    greParent_maybe :: GlobalRdrEltX info -> Maybe Name
    greParent_maybe :: forall info. GlobalRdrEltX info -> Maybe Name
    greParent_maybe GlobalRdrEltX info
    gre = case GlobalRdrEltX info -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par GlobalRdrEltX info
    gre of
                            Parent
    NoParent      -> Maybe Name
    forall a. Maybe a
    Nothing
                            ParentIs Name
    n    -> Name -> Maybe Name
    forall a. a -> Maybe a
    Just Name
    n

    gresToNameSet :: [GlobalRdrEltX info] -> NameSet
    gresToNameSet :: forall info. [GlobalRdrEltX info] -> NameSet
    gresToNameSet [GlobalRdrEltX info]
    gres = (GlobalRdrEltX info -> NameSet -> NameSet)
    -> NameSet -> [GlobalRdrEltX info] -> NameSet
    forall a b. (a -> b -> b) -> b -> [a] -> b
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr GlobalRdrEltX info -> NameSet -> NameSet
    forall {info}. GlobalRdrEltX info -> NameSet -> NameSet
    add NameSet
    emptyNameSet [GlobalRdrEltX info]
    gres
      where add :: GlobalRdrEltX info -> NameSet -> NameSet
    add GlobalRdrEltX info
    gre NameSet
    set = NameSet -> Name -> NameSet
    extendNameSet NameSet
    set (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre)

    -- | Takes a list of distinct GREs and folds them
    -- into AvailInfos. This is more efficient than mapping each individual
    -- GRE to an AvailInfo and then folding using `plusAvail`, but needs the
    -- uniqueness assumption.
    gresToAvailInfo :: forall info. [GlobalRdrEltX info] -> [AvailInfo]
    gresToAvailInfo :: forall info. [GlobalRdrEltX info] -> [AvailInfo]
    gresToAvailInfo [GlobalRdrEltX info]
    gres
      = NameEnv AvailInfo -> [AvailInfo]
    forall a. NameEnv a -> [a]
    nonDetNameEnvElts NameEnv AvailInfo
    avail_env
      where
        avail_env :: NameEnv AvailInfo -- Keyed by the parent
        (NameEnv AvailInfo
    avail_env, NameSet
    _) = ((NameEnv AvailInfo, NameSet)
     -> GlobalRdrEltX info -> (NameEnv AvailInfo, NameSet))
    -> (NameEnv AvailInfo, NameSet)
    -> [GlobalRdrEltX info]
    -> (NameEnv AvailInfo, NameSet)
    forall b a. (b -> a -> b) -> b -> [a] -> b
    forall (t :: * -> *) b a.
    Foldable t =>
    (b -> a -> b) -> b -> t a -> b
    foldl' (NameEnv AvailInfo, NameSet)
    -> GlobalRdrEltX info -> (NameEnv AvailInfo, NameSet)
    add (NameEnv AvailInfo
    forall a. NameEnv a
    emptyNameEnv, NameSet
    emptyNameSet) [GlobalRdrEltX info]
    gres

        add :: (NameEnv AvailInfo, NameSet)
            -> GlobalRdrEltX info
            -> (NameEnv AvailInfo, NameSet)
        add :: (NameEnv AvailInfo, NameSet)
    -> GlobalRdrEltX info -> (NameEnv AvailInfo, NameSet)
    add (NameEnv AvailInfo
    env, NameSet
    done) GlobalRdrEltX info
    gre
          | Name
    name Name -> NameSet -> Bool
    `elemNameSet` NameSet
    done
          = (NameEnv AvailInfo
    env, NameSet
    done)  -- Don't insert twice into the AvailInfo
          | Bool
    otherwise
          = ( (GlobalRdrEltX info -> AvailInfo -> AvailInfo)
    -> (GlobalRdrEltX info -> AvailInfo)
    -> NameEnv AvailInfo
    -> Name
    -> GlobalRdrEltX info
    -> NameEnv AvailInfo
    forall a b.
    (a -> b -> b) -> (a -> b) -> NameEnv b -> Name -> a -> NameEnv b
    extendNameEnv_Acc GlobalRdrEltX info -> AvailInfo -> AvailInfo
    comb GlobalRdrEltX info -> AvailInfo
    forall info. GlobalRdrEltX info -> AvailInfo
    availFromGRE NameEnv AvailInfo
    env Name
    key GlobalRdrEltX info
    gre
            , NameSet
    done NameSet -> Name -> NameSet
    `extendNameSet` Name
    name )
          where
            name :: Name
    name = GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre
            key :: Name
    key = case GlobalRdrEltX info -> Maybe Name
    forall info. GlobalRdrEltX info -> Maybe Name
    greParent_maybe GlobalRdrEltX info
    gre of
                     Just Name
    parent -> Name
    parent
                     Maybe Name
    Nothing     -> GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre

            -- We want to insert the child `k` into a list of children but
            -- need to maintain the invariant that the parent is first.
            --
            -- We also use the invariant that `k` is not already in `ns`.
            insertChildIntoChildren :: Name -> [Name] -> Name -> [Name]
            insertChildIntoChildren :: Name -> [Name] -> Name -> [Name]
    insertChildIntoChildren Name
    _ [] Name
    k = [Name
    k]
            insertChildIntoChildren Name
    p (Name
    n:[Name]
    ns) Name
    k
              | Name
    p Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    == Name
    k    = Name
    kName -> [Name] -> [Name]
    forall a. a -> [a] -> [a]
    :Name
    nName -> [Name] -> [Name]
    forall a. a -> [a] -> [a]
    :[Name]
    ns
              | Bool
    otherwise = Name
    nName -> [Name] -> [Name]
    forall a. a -> [a] -> [a]
    :Name
    kName -> [Name] -> [Name]
    forall a. a -> [a] -> [a]
    :[Name]
    ns

            comb :: GlobalRdrEltX info -> AvailInfo -> AvailInfo
            comb :: GlobalRdrEltX info -> AvailInfo -> AvailInfo
    comb GlobalRdrEltX info
    _   (Avail Name
    n) = Name -> AvailInfo
    Avail Name
    n -- Duplicated name, should not happen
            comb GlobalRdrEltX info
    gre (AvailTC Name
    m [Name]
    ns)
              = case GlobalRdrEltX info -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par GlobalRdrEltX info
    gre of
                  Parent
    NoParent    -> Name -> [Name] -> AvailInfo
    AvailTC Name
    m (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    greName -> [Name] -> [Name]
    forall a. a -> [a] -> [a]
    :[Name]
    ns) -- Not sure this ever happens
                  ParentIs {} -> Name -> [Name] -> AvailInfo
    AvailTC Name
    m (Name -> [Name] -> Name -> [Name]
    insertChildIntoChildren Name
    m [Name]
    ns (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre))

    availFromGRE :: GlobalRdrEltX info -> AvailInfo
    availFromGRE :: forall info. GlobalRdrEltX info -> AvailInfo
    availFromGRE (GRE { gre_name :: forall info. GlobalRdrEltX info -> Name
    gre_name = Name
    child, gre_par :: forall info. GlobalRdrEltX info -> Parent
    gre_par = Parent
    parent })
      = case Parent
    parent of
          ParentIs Name
    p
            -> Name -> [Name] -> AvailInfo
    AvailTC Name
    p [Name
    child]
          Parent
    NoParent
            | Name -> Bool
    isTyConName Name
    child -- NB: don't force the GREInfo field unnecessarily.
            -> Name -> [Name] -> AvailInfo
    AvailTC Name
    child [Name
    child]
            | Bool
    otherwise
            -> Name -> AvailInfo
    Avail Name
    child

    emptyGlobalRdrEnv :: GlobalRdrEnvX info
    emptyGlobalRdrEnv :: forall info. GlobalRdrEnvX info
    emptyGlobalRdrEnv = OccEnv [GlobalRdrEltX info]
    forall a. OccEnv a
    emptyOccEnv

    globalRdrEnvElts :: GlobalRdrEnvX info -> [GlobalRdrEltX info]
    globalRdrEnvElts :: forall info. GlobalRdrEnvX info -> [GlobalRdrEltX info]
    globalRdrEnvElts GlobalRdrEnvX info
    env = ([GlobalRdrEltX info]
     -> [GlobalRdrEltX info] -> [GlobalRdrEltX info])
    -> [GlobalRdrEltX info]
    -> GlobalRdrEnvX info
    -> [GlobalRdrEltX info]
    forall a b. (a -> b -> b) -> b -> OccEnv a -> b
    nonDetFoldOccEnv [GlobalRdrEltX info]
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a. [a] -> [a] -> [a]
    (++) [] GlobalRdrEnvX info
    env

    -- | Drop all 'GREInfo' fields in a 'GlobalRdrEnv' in order to
    -- avoid space leaks.
    -- See Note [Forcing GREInfo] in GHC.Types.GREInfo.
    forceGlobalRdrEnv :: GlobalRdrEnvX info -> IfGlobalRdrEnv
    forceGlobalRdrEnv :: forall info. GlobalRdrEnvX info -> IfGlobalRdrEnv
    forceGlobalRdrEnv GlobalRdrEnvX info
    rdrs =
      ([GlobalRdrEltX info] -> [GlobalRdrEltX ()])
    -> GlobalRdrEnvX info -> IfGlobalRdrEnv
    forall a b. (a -> b) -> OccEnv a -> OccEnv b
    strictMapOccEnv ((GlobalRdrEltX info -> GlobalRdrEltX ())
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX ()]
    forall a b. (a -> b) -> [a] -> [b]
    strictMap (\ GlobalRdrEltX info
    gre -> GlobalRdrEltX info
    gre { gre_info = ()})) GlobalRdrEnvX info
    rdrs

    -- | Hydrate a previously dehydrated 'GlobalRdrEnv',
    -- by (lazily!) looking up the 'GREInfo' using the provided function.
    --
    -- See Note [Forcing GREInfo] in GHC.Types.GREInfo.
    hydrateGlobalRdrEnv :: forall info noInfo
                        .  (Name -> IO info)
                        -> GlobalRdrEnvX noInfo -> GlobalRdrEnvX info
    hydrateGlobalRdrEnv :: forall info noInfo.
    (Name -> IO info) -> GlobalRdrEnvX noInfo -> GlobalRdrEnvX info
    hydrateGlobalRdrEnv Name -> IO info
    f = ([GlobalRdrEltX noInfo] -> [GlobalRdrEltX info])
    -> OccEnv [GlobalRdrEltX noInfo] -> OccEnv [GlobalRdrEltX info]
    forall a b. (a -> b) -> OccEnv a -> OccEnv b
    mapOccEnv ((GlobalRdrEltX noInfo -> GlobalRdrEltX info)
    -> [GlobalRdrEltX noInfo] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> [a] -> [b]
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap GlobalRdrEltX noInfo -> GlobalRdrEltX info
    g)
      where
        g :: GlobalRdrEltX noInfo -> GlobalRdrEltX info
    g GlobalRdrEltX noInfo
    gre = GlobalRdrEltX noInfo
    gre { gre_info = unsafePerformIO $ f (greName gre) }
        -- NB: use unsafePerformIO to delay the lookup until it is forced.
        -- See also 'GHC.Rename.Env.lookupGREInfo'.

    instance Outputable info => Outputable (GlobalRdrEltX info) where
      ppr :: GlobalRdrEltX info -> SDoc
    ppr GlobalRdrEltX info
    gre = SDoc -> Int -> SDoc -> SDoc
    hang (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre) SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Parent -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (GlobalRdrEltX info -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par GlobalRdrEltX info
    gre) SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> info -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (GlobalRdrEltX info -> info
    forall info. GlobalRdrEltX info -> info
    gre_info GlobalRdrEltX info
    gre))
                   Int
    2 (GlobalRdrEltX info -> SDoc
    forall info. GlobalRdrEltX info -> SDoc
    pprNameProvenance GlobalRdrEltX info
    gre)

    pprGlobalRdrEnv :: Bool -> GlobalRdrEnv -> SDoc
    pprGlobalRdrEnv :: Bool -> GlobalRdrEnv -> SDoc
    pprGlobalRdrEnv Bool
    locals_only GlobalRdrEnv
    env
      = [SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "GlobalRdrEnv" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Bool -> SDoc -> SDoc
    forall doc. IsOutput doc => Bool -> doc -> doc
    ppWhen Bool
    locals_only (String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "(locals only)")
                 SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc
    forall doc. IsLine doc => doc
    lbrace
             , Int -> SDoc -> SDoc
    nest Int
    2 ([SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [ [GlobalRdrElt] -> SDoc
    forall {info}. Outputable info => [GlobalRdrEltX info] -> SDoc
    pp ([GlobalRdrElt] -> [GlobalRdrElt]
    remove_locals [GlobalRdrElt]
    gre_list) | [GlobalRdrElt]
    gre_list <- GlobalRdrEnv -> [[GlobalRdrElt]]
    forall a. OccEnv a -> [a]
    nonDetOccEnvElts GlobalRdrEnv
    env ]
                 SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc
    forall doc. IsLine doc => doc
    rbrace) ]
      where
        remove_locals :: [GlobalRdrElt] -> [GlobalRdrElt]
    remove_locals [GlobalRdrElt]
    gres | Bool
    locals_only = (GlobalRdrElt -> Bool) -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a. (a -> Bool) -> [a] -> [a]
    filter GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isLocalGRE [GlobalRdrElt]
    gres
                           | Bool
    otherwise   = [GlobalRdrElt]
    gres
        pp :: [GlobalRdrEltX info] -> SDoc
    pp []   = SDoc
    forall doc. IsOutput doc => doc
    empty
        pp gres :: [GlobalRdrEltX info]
    gres@(GlobalRdrEltX info
    gre:[GlobalRdrEltX info]
    _) = SDoc -> Int -> SDoc -> SDoc
    hang (OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr OccName
    occ SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <> SDoc
    forall doc. IsLine doc => doc
    colon)
                             Int
    2 ([SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat ((GlobalRdrEltX info -> SDoc) -> [GlobalRdrEltX info] -> [SDoc]
    forall a b. (a -> b) -> [a] -> [b]
    map GlobalRdrEltX info -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [GlobalRdrEltX info]
    gres))
          where
            occ :: OccName
    occ = Name -> OccName
    nameOccName (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre)

    {-
    Note [NoFieldSelectors]
    ~~~~~~~~~~~~~~~~~~~~~~~
    The NoFieldSelectors extension allows record fields to be defined without
    bringing the corresponding selector functions into scope.  However, such fields
    may still be used in contexts such as record construction, pattern matching or
    update. This requires us to distinguish contexts in which selectors are required
    from those in which any field may be used.  For example:

      {-# LANGUAGE NoFieldSelectors #-}
      module M (T(foo), foo) where  -- T(foo) refers to the field,
                                    -- unadorned foo to the value binding
        data T = MkT { foo :: Int }
        foo = ()

        bar = foo -- refers to the value binding, field ignored

      module N where
        import M (T(..))
        baz = MkT { foo = 3 } -- refers to the field
        oops = foo -- an error: the field is in scope but the value binding is not

    Each 'FieldLabel' indicates (in the 'flHasFieldSelector' field) whether the
    FieldSelectors extension was enabled in the defining module.  This allows them
    to be filtered out by 'filterFieldGREs'.

    Even when NoFieldSelectors is in use, we still generate selector functions
    internally. For example, the expression
       getField @"foo" t
    or (with dot-notation)
       t.foo
    extracts the `foo` field of t::T, and hence needs the selector function
    (see Note [HasField instances] in GHC.Tc.Instance.Class).

    In many of the name lookup functions in this module we pass a FieldsOrSelectors
    value, indicating what we are looking for:

     * WantNormal: fields are in scope only if they have an accompanying selector
       function, e.g. we are looking up a variable in an expression
       (lookupExprOccRn).

     * WantBoth: any name or field will do, regardless of whether the selector
       function is available, e.g. record updates (lookupRecUpdFields) with
       NoDisambiguateRecordFields.

     * WantField: any field will do, regardless of whether the selector function is
       available, but ignoring any non-field names, e.g. record updates
       (lookupRecUpdFields with DisambiguateRecordFields.

    -----------------------------------------------------------------------------------
      Context                                  FieldsOrSelectors
    -----------------------------------------------------------------------------------
      Record construction/pattern match        WantField, but unless DisambiguateRecordFields
      e.g. MkT { foo = 3 }                     is in effect, also look up using WantBoth
      Record update, e.g. e { foo = 3 }        to report when a non-field clashes with a field.

      :info in GHCi                            WantBoth

      Variable occurrence in expression        WantNormal
      Type variable, data constructor
      Pretty much everything else
    -----------------------------------------------------------------------------------
    -}

    fieldGRE_maybe :: GlobalRdrElt -> Maybe FieldGlobalRdrElt
    fieldGRE_maybe :: GlobalRdrElt -> Maybe GlobalRdrElt
    fieldGRE_maybe GlobalRdrElt
    gre = do
      Bool -> Maybe ()
    forall (f :: * -> *). Alternative f => Bool -> f ()
    guard (GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre)
      GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. a -> Maybe a
    forall (m :: * -> *) a. Monad m => a -> m a
    return GlobalRdrElt
    gre

    fieldGRELabel :: HasDebugCallStack => FieldGlobalRdrElt -> FieldLabel
    fieldGRELabel :: HasDebugCallStack => GlobalRdrElt -> FieldLabel
    fieldGRELabel = RecFieldInfo -> FieldLabel
    recFieldLabel (RecFieldInfo -> FieldLabel)
    -> (GlobalRdrElt -> RecFieldInfo) -> GlobalRdrElt -> FieldLabel
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . HasDebugCallStack => GlobalRdrElt -> RecFieldInfo
    GlobalRdrElt -> RecFieldInfo
    fieldGREInfo

    fieldGREInfo :: HasDebugCallStack => FieldGlobalRdrElt -> RecFieldInfo
    fieldGREInfo :: HasDebugCallStack => GlobalRdrElt -> RecFieldInfo
    fieldGREInfo GlobalRdrElt
    gre
      = Bool -> SDoc -> RecFieldInfo -> RecFieldInfo
    forall a. HasCallStack => Bool -> SDoc -> a -> a
    assertPpr (GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre) (GlobalRdrElt -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GlobalRdrElt
    gre) (RecFieldInfo -> RecFieldInfo) -> RecFieldInfo -> RecFieldInfo
    forall a b. (a -> b) -> a -> b
    $
        case GlobalRdrElt -> GREInfo
    greInfo GlobalRdrElt
    gre of
          IAmRecField RecFieldInfo
    info -> RecFieldInfo
    info
          GREInfo
    info -> String -> SDoc -> RecFieldInfo
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "fieldGREInfo" (SDoc -> RecFieldInfo) -> SDoc -> RecFieldInfo
    forall a b. (a -> b) -> a -> b
    $
            [SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "gre_name:" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (GlobalRdrElt -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrElt
    gre)
                 , String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "info:" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> GREInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GREInfo
    info ]

    recFieldConLike_maybe :: HasDebugCallStack => GlobalRdrElt -> Maybe ConInfo
    recFieldConLike_maybe :: HasDebugCallStack => GlobalRdrElt -> Maybe ConInfo
    recFieldConLike_maybe GlobalRdrElt
    gre =
      case GlobalRdrElt -> GREInfo
    greInfo GlobalRdrElt
    gre of
        IAmConLike ConInfo
    info -> ConInfo -> Maybe ConInfo
    forall a. a -> Maybe a
    Just ConInfo
    info
        GREInfo
    _               -> Maybe ConInfo
    forall a. Maybe a
    Nothing

    recFieldInfo_maybe :: HasDebugCallStack => GlobalRdrElt -> Maybe RecFieldInfo
    recFieldInfo_maybe :: HasDebugCallStack => GlobalRdrElt -> Maybe RecFieldInfo
    recFieldInfo_maybe GlobalRdrElt
    gre =
      case GlobalRdrElt -> GREInfo
    greInfo GlobalRdrElt
    gre of
        IAmRecField RecFieldInfo
    info -> Bool -> SDoc -> Maybe RecFieldInfo -> Maybe RecFieldInfo
    forall a. HasCallStack => Bool -> SDoc -> a -> a
    assertPpr (GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre) (GlobalRdrElt -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GlobalRdrElt
    gre) (Maybe RecFieldInfo -> Maybe RecFieldInfo)
    -> Maybe RecFieldInfo -> Maybe RecFieldInfo
    forall a b. (a -> b) -> a -> b
    $ RecFieldInfo -> Maybe RecFieldInfo
    forall a. a -> Maybe a
    Just RecFieldInfo
    info
        GREInfo
    _                -> Maybe RecFieldInfo
    forall a. Maybe a
    Nothing

    -- | When looking up GREs, we may or may not want to include fields that were
    -- defined in modules with @NoFieldSelectors@ enabled.  See Note
    -- [NoFieldSelectors].
    data FieldsOrSelectors
        = WantNormal -- ^ Include normal names, and fields with selectors, but
                     -- ignore fields without selectors.
        | WantBoth   -- ^ Include normal names and all fields (regardless of whether
                     -- they have selectors).
        | WantField  -- ^ Include only fields, with or without selectors, ignoring
                     -- any non-fields in scope.
      deriving (FieldsOrSelectors -> FieldsOrSelectors -> Bool
    (FieldsOrSelectors -> FieldsOrSelectors -> Bool)
    -> (FieldsOrSelectors -> FieldsOrSelectors -> Bool)
    -> Eq FieldsOrSelectors
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: FieldsOrSelectors -> FieldsOrSelectors -> Bool
    == :: FieldsOrSelectors -> FieldsOrSelectors -> Bool
    $c/= :: FieldsOrSelectors -> FieldsOrSelectors -> Bool
    /= :: FieldsOrSelectors -> FieldsOrSelectors -> Bool
    Eq, Int -> FieldsOrSelectors -> ShowS
    [FieldsOrSelectors] -> ShowS
    FieldsOrSelectors -> String
    (Int -> FieldsOrSelectors -> ShowS)
    -> (FieldsOrSelectors -> String)
    -> ([FieldsOrSelectors] -> ShowS)
    -> Show FieldsOrSelectors
    forall a.
    (Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
    $cshowsPrec :: Int -> FieldsOrSelectors -> ShowS
    showsPrec :: Int -> FieldsOrSelectors -> ShowS
    $cshow :: FieldsOrSelectors -> String
    show :: FieldsOrSelectors -> String
    $cshowList :: [FieldsOrSelectors] -> ShowS
    showList :: [FieldsOrSelectors] -> ShowS
    Show)

    filterFieldGREs :: FieldsOrSelectors -> [GlobalRdrElt] -> [GlobalRdrElt]
    filterFieldGREs :: FieldsOrSelectors -> [GlobalRdrElt] -> [GlobalRdrElt]
    filterFieldGREs FieldsOrSelectors
    WantBoth = [GlobalRdrElt] -> [GlobalRdrElt]
    forall a. a -> a
    id
    filterFieldGREs FieldsOrSelectors
    fos = (GlobalRdrElt -> Bool) -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a. (a -> Bool) -> [a] -> [a]
    filter (FieldsOrSelectors -> GlobalRdrElt -> Bool
    allowGRE FieldsOrSelectors
    fos)

    allowGRE :: FieldsOrSelectors -> GlobalRdrElt -> Bool
    allowGRE :: FieldsOrSelectors -> GlobalRdrElt -> Bool
    allowGRE FieldsOrSelectors
    WantBoth   GlobalRdrElt
    _
      = Bool
    True
    allowGRE FieldsOrSelectors
    WantNormal GlobalRdrElt
    gre
      -- NB: we only need to consult the GREInfo for record field GREs,
      -- to check whether they define field selectors.
      -- By checking 'isRecFldGRE' first, which only consults the NameSpace,
      -- we avoid forcing the GREInfo for things that aren't record fields.
      | GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre
      = FieldLabel -> FieldSelectors
    flHasFieldSelector (HasDebugCallStack => GlobalRdrElt -> FieldLabel
    GlobalRdrElt -> FieldLabel
    fieldGRELabel GlobalRdrElt
    gre) FieldSelectors -> FieldSelectors -> Bool
    forall a. Eq a => a -> a -> Bool
    == FieldSelectors
    FieldSelectors
      | Bool
    otherwise
      = Bool
    True
    allowGRE FieldsOrSelectors
    WantField GlobalRdrElt
    gre
      = GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre

    -- | What should we look up in a 'GlobalRdrEnv'? Should we only look up
    -- names with the exact same 'OccName', or do we allow different 'NameSpace's?
    --
    -- Depending on the answer, we might need more or less information from the
    -- 'GlobalRdrEnv', e.g. if we want to include matching record fields we need
    -- to know if the corresponding record fields define field selectors, for which
    -- we need to consult the 'GREInfo'. This is why this datatype is a GADT.
    --
    -- See Note [IfGlobalRdrEnv].
    data LookupGRE info where
      -- | Look for this specific 'OccName', with the exact same 'NameSpace',
      -- in the 'GlobalRdrEnv'.
      LookupOccName :: OccName -- ^ the 'OccName' to look up
                    -> WhichGREs info
                        -- ^ information about other relevant 'NameSpace's
                    -> LookupGRE info

      -- | Look up the 'OccName' of this 'RdrName' in the 'GlobalRdrEnv',
      -- filtering out those whose qualification matches that of the 'RdrName'.
      --
      -- Lookup returns an empty result for 'Exact' or 'Orig' 'RdrName's.
      LookupRdrName :: RdrName -- ^ the 'RdrName' to look up
                    -> WhichGREs info
                        -- ^ information about other relevant 'NameSpace's
                    -> LookupGRE info

      -- | Look for 'GRE's with the same unique as the given 'Name'
      -- in the 'GlobalRdrEnv'.
      LookupExactName
        :: { forall info. LookupGRE info -> Name
    lookupExactName :: Name
              -- ^ the 'Name' to look up
           , forall info. LookupGRE info -> Bool
    lookInAllNameSpaces :: Bool
              -- ^ whether to look in *all* 'NameSpace's, or just
              -- in the 'NameSpace' of the 'Name'
              -- See Note [Template Haskell ambiguity]
           }
        -> LookupGRE info

      -- | Look up children 'GlobalRdrElt's with a given 'Parent'.
      LookupChildren
        :: OccName  -- ^ the 'OccName' to look up
        -> LookupChild
             -- ^ information to decide which 'GlobalRdrElt's
             -- are valid children after looking up
        -> LookupGRE info

    -- | How should we look up in a 'GlobalRdrEnv'?
    -- Which 'NameSpace's are considered relevant for a given lookup?
    data WhichGREs info where
      -- | Only consider 'GlobalRdrElt's with the exact 'NameSpace' we look up.
      SameNameSpace :: WhichGREs info
      -- | Allow 'GlobalRdrElt's with different 'NameSpace's, e.g. allow looking up
      -- record fields from the variable 'NameSpace', or looking up a 'TyCon' from
      -- the data constructor 'NameSpace'.
      RelevantGREs
        :: { WhichGREs GREInfo -> FieldsOrSelectors
    includeFieldSelectors :: !FieldsOrSelectors
            -- ^ how should we handle looking up variables?
            --
            --   - should we include record fields defined with @-XNoFieldSelectors@?
            --   - should we include non-fields?
            --
            -- See Note [NoFieldSelectors].
           , WhichGREs GREInfo -> Bool
    lookupVariablesForFields :: !Bool
              -- ^ when looking up a record field, should we also look up plain variables?
           , WhichGREs GREInfo -> Bool
    lookupTyConsAsWell :: !Bool
              -- ^ when looking up a variable, field or data constructor, should we
              -- also try the type constructor 'NameSpace'?
           }
        -> WhichGREs GREInfo

    instance Outputable (WhichGREs info) where
      ppr :: WhichGREs info -> SDoc
    ppr WhichGREs info
    SameNameSpace = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "SameNameSpace"
      ppr (RelevantGREs { includeFieldSelectors :: WhichGREs GREInfo -> FieldsOrSelectors
    includeFieldSelectors = FieldsOrSelectors
    sel
                        , lookupVariablesForFields :: WhichGREs GREInfo -> Bool
    lookupVariablesForFields = Bool
    vars
                        , lookupTyConsAsWell :: WhichGREs GREInfo -> Bool
    lookupTyConsAsWell = Bool
    tcs_too })
        = SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    braces (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ [SDoc] -> SDoc
    forall doc. IsLine doc => [doc] -> doc
    hsep
           [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "RelevantGREs"
           , String -> SDoc
    forall doc. IsLine doc => String -> doc
    text (FieldsOrSelectors -> String
    forall a. Show a => a -> String
    show FieldsOrSelectors
    sel)
           , if Bool
    vars then String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "[vars]" else SDoc
    forall doc. IsOutput doc => doc
    empty
           , if Bool
    tcs_too then String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "[tcs]" else SDoc
    forall doc. IsOutput doc => doc
    empty ]

    -- | Look up as many possibly relevant 'GlobalRdrElt's as possible.
    pattern AllRelevantGREs :: WhichGREs GREInfo
    pattern $mAllRelevantGREs :: forall {r}. WhichGREs GREInfo -> ((# #) -> r) -> ((# #) -> r) -> r
    $bAllRelevantGREs :: WhichGREs GREInfo
    AllRelevantGREs =
      RelevantGREs { includeFieldSelectors = WantBoth
                   , lookupVariablesForFields = True
                   , lookupTyConsAsWell = True }

    -- | Look up relevant GREs, taking into account the interaction between the
    -- variable and field 'NameSpace's as determined by the 'FieldsOrSelector'
    -- argument.
    pattern RelevantGREsFOS :: FieldsOrSelectors -> WhichGREs GREInfo
    pattern $mRelevantGREsFOS :: forall {r}.
    WhichGREs GREInfo -> (FieldsOrSelectors -> r) -> ((# #) -> r) -> r
    $bRelevantGREsFOS :: FieldsOrSelectors -> WhichGREs GREInfo
    RelevantGREsFOS fos <- RelevantGREs { includeFieldSelectors = fos }
      where
        RelevantGREsFOS FieldsOrSelectors
    fos =
          RelevantGREs { includeFieldSelectors :: FieldsOrSelectors
    includeFieldSelectors = FieldsOrSelectors
    fos
                       , lookupVariablesForFields :: Bool
    lookupVariablesForFields = FieldsOrSelectors
    fos FieldsOrSelectors -> FieldsOrSelectors -> Bool
    forall a. Eq a => a -> a -> Bool
    == FieldsOrSelectors
    WantBoth
                       , lookupTyConsAsWell :: Bool
    lookupTyConsAsWell = Bool
    False }

    data LookupChild
      = LookupChild
      { LookupChild -> Name
    wantedParent :: Name
         -- ^ the parent we are looking up children of
      , LookupChild -> Bool
    lookupDataConFirst :: Bool
         -- ^ for type constructors, should we look in the data constructor
         -- namespace first?
      , LookupChild -> Bool
    prioritiseParent :: Bool
        -- ^ should we prioritise getting the right 'Parent'?
        --
        --  - @True@: prioritise getting the right 'Parent'
        --  - @False@: prioritise getting the right 'NameSpace'
        --
        -- See Note [childGREPriority].
      }

    instance Outputable LookupChild where
      ppr :: LookupChild -> SDoc
    ppr (LookupChild { wantedParent :: LookupChild -> Name
    wantedParent = Name
    par
                       , lookupDataConFirst :: LookupChild -> Bool
    lookupDataConFirst = Bool
    dc
                       , prioritiseParent :: LookupChild -> Bool
    prioritiseParent = Bool
    prio_parent })
        = SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    braces (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ [SDoc] -> SDoc
    forall doc. IsLine doc => [doc] -> doc
    hsep
            [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "LookupChild"
            , SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    braces (String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "parent:" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    par)
            , if Bool
    dc then String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "[dc_first]" else SDoc
    forall doc. IsOutput doc => doc
    empty
            , if Bool
    prio_parent then String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "[prio_parent]" else SDoc
    forall doc. IsOutput doc => doc
    empty
            ]

    -- | After looking up something with the given 'NameSpace', is the resulting
    -- 'GlobalRdrElt' we have obtained relevant, according to the 'RelevantGREs'
    -- specification of which 'NameSpace's are relevant?
    greIsRelevant :: WhichGREs GREInfo -- ^ specification of which 'GlobalRdrElt's to consider relevant
                  -> NameSpace    -- ^ the 'NameSpace' of the thing we are looking up
                  -> GlobalRdrElt -- ^ the 'GlobalRdrElt' we have looked up, in a
                                  -- potentially different 'NameSpace' than we wanted
                  -> Bool
    greIsRelevant :: WhichGREs GREInfo -> NameSpace -> GlobalRdrElt -> Bool
    greIsRelevant WhichGREs GREInfo
    which_gres NameSpace
    ns GlobalRdrElt
    gre
      | NameSpace
    ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    other_ns
      = Bool
    True
      | Bool
    otherwise
      = case WhichGREs GREInfo
    which_gres of
          WhichGREs GREInfo
    SameNameSpace -> Bool
    False
          RelevantGREs { includeFieldSelectors :: WhichGREs GREInfo -> FieldsOrSelectors
    includeFieldSelectors = FieldsOrSelectors
    fos
                       , lookupVariablesForFields :: WhichGREs GREInfo -> Bool
    lookupVariablesForFields = Bool
    vars_for_flds
                       , lookupTyConsAsWell :: WhichGREs GREInfo -> Bool
    lookupTyConsAsWell = Bool
    tycons_too }
            | NameSpace
    ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    varName
            -> (NameSpace -> Bool
    isFieldNameSpace NameSpace
    other_ns Bool -> Bool -> Bool
    && FieldsOrSelectors -> GlobalRdrElt -> Bool
    allowGRE FieldsOrSelectors
    fos GlobalRdrElt
    gre) Bool -> Bool -> Bool
    || Bool
    tc_too
            | NameSpace -> Bool
    isFieldNameSpace NameSpace
    ns
            -> Bool
    vars_for_flds Bool -> Bool -> Bool
    &&
              (  NameSpace
    other_ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    varName
              Bool -> Bool -> Bool
    || (NameSpace -> Bool
    isFieldNameSpace NameSpace
    other_ns Bool -> Bool -> Bool
    && FieldsOrSelectors -> GlobalRdrElt -> Bool
    allowGRE FieldsOrSelectors
    fos GlobalRdrElt
    gre)
              Bool -> Bool -> Bool
    || Bool
    tc_too )
            | NameSpace -> Bool
    isDataConNameSpace NameSpace
    ns
            -> Bool
    tc_too
            | Bool
    otherwise
            -> Bool
    False
            where
              tc_too :: Bool
    tc_too = Bool
    tycons_too Bool -> Bool -> Bool
    && NameSpace -> Bool
    isTcClsNameSpace NameSpace
    other_ns
      where
        other_ns :: NameSpace
    other_ns = GlobalRdrElt -> NameSpace
    forall info. GlobalRdrEltX info -> NameSpace
    greNameSpace GlobalRdrElt
    gre

    {- Note [childGREPriority]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~
    There are currently two places in the compiler where we look up GlobalRdrElts
    which have a given Parent. These are the two calls to lookupSubBndrOcc_helper:

      A. Looking up children in an export item, e.g.

           module M ( T(MkT, D) ) where { data T = MkT; data D = D }

      B. Looking up binders in a class or instance declaration, e.g.
         the operator +++ in the fixity declaration:

           class C a where { type (+++) :: a -> a ->; infixl 6 +++ }
           (+++) :: Int -> Int -> Int; (+++) = (+)

    In these two situations, there are two competing metrics for finding the "best"
    'GlobalRdrElt' that a particular 'OccName' resolves to:

      - does the resolved 'GlobalRdrElt' have the correct parent?
      - does the resolved 'GlobalRdrElt' have the same 'NameSpace' as the 'OccName'?

    (A) and (B) have competing requirements.

    For the example of (A) above, we know that the child 'D' of 'T' must live
    in the data namespace, so we look up the OccName 'OccName DataName "D"' and
    prioritise the lookup results based on the 'NameSpace'.
    This means we get an error message of the form:

      The type constructor 'T' is not the parent of the data constructor 'D'.

    as opposed to the rather unhelpful and confusing:

      The type constructor 'T' is not the parent of the type constructor 'D'.

    See test case T11970.

    For the example of (B) above, the fixity declaration for +++ lies inside the
    class, so we should prioritise looking up 'GlobalRdrElt's whose parent is 'C'.
    Not doing so led to #23664.
    -}

    -- | Scoring priority function for looking up children 'GlobalRdrElt'.
    --
    -- We score by 'Parent' and 'NameSpace', with higher priorities having lower
    -- numbers. Which lexicographic order we use ('Parent' or 'NameSpace' first)
    -- is determined by the first argument; see Note [childGREPriority].
    childGREPriority :: LookupChild -- ^ what kind of child do we want,
                                    -- e.g. what should its parent be?
                     -> NameSpace   -- ^ what 'NameSpace' are we originally looking in?
                     -> GlobalRdrEltX info
                                    -- ^ the result of looking up; it might be in a different
                                    -- 'NameSpace', which is used to determine the score
                                    -- (in the first component)
                     -> Maybe (Int, Int)
    childGREPriority :: forall info.
    LookupChild -> NameSpace -> GlobalRdrEltX info -> Maybe (Int, Int)
    childGREPriority (LookupChild { wantedParent :: LookupChild -> Name
    wantedParent = Name
    wanted_parent
                                  , lookupDataConFirst :: LookupChild -> Bool
    lookupDataConFirst = Bool
    try_dc_first
                                  , prioritiseParent :: LookupChild -> Bool
    prioritiseParent = Bool
    par_first })
      NameSpace
    ns GlobalRdrEltX info
    gre =
        case NameSpace -> Maybe Int
    child_ns_prio (NameSpace -> Maybe Int) -> NameSpace -> Maybe Int
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEltX info -> NameSpace
    forall info. GlobalRdrEltX info -> NameSpace
    greNameSpace GlobalRdrEltX info
    gre of
          Maybe Int
    Nothing -> Maybe (Int, Int)
    forall a. Maybe a
    Nothing
          Just Int
    ns_prio ->
            let par_prio :: Int
    par_prio = Parent -> Int
    parent_prio (Parent -> Int) -> Parent -> Int
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEltX info -> Parent
    forall info. GlobalRdrEltX info -> Parent
    greParent GlobalRdrEltX info
    gre
            in (Int, Int) -> Maybe (Int, Int)
    forall a. a -> Maybe a
    Just ((Int, Int) -> Maybe (Int, Int)) -> (Int, Int) -> Maybe (Int, Int)
    forall a b. (a -> b) -> a -> b
    $ if Bool
    par_first
                      then (Int
    par_prio, Int
    ns_prio)
                      else (Int
    ns_prio, Int
    par_prio)
              -- See Note [childGREPriority].

      where
          -- Pick out the possible 'NameSpace's in order of priority.
          child_ns_prio :: (NameSpace -> Maybe Int)
          child_ns_prio :: NameSpace -> Maybe Int
    child_ns_prio NameSpace
    other_ns
            | NameSpace
    other_ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    ns
            = Int -> Maybe Int
    forall a. a -> Maybe a
    Just Int
    0
            | NameSpace -> Bool
    isTermVarOrFieldNameSpace NameSpace
    ns
            , NameSpace -> Bool
    isTermVarOrFieldNameSpace NameSpace
    other_ns
            = Int -> Maybe Int
    forall a. a -> Maybe a
    Just Int
    0
            | NameSpace -> Bool
    isValNameSpace NameSpace
    varName
            , NameSpace
    other_ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    tcName
            -- When looking up children, we sometimes want a value name
            -- to resolve to a type constructor.
            -- For example, for an infix declaration "infixr 3 +!" or "infix 2 `Fun`"
            -- inside a class declaration, we want to account for the possibility
            -- that the identifier refers to an associated type (type constructor
            -- NameSpace), when otherwise "+!" would be in the term-level variable
            -- NameSpace, and "Fun" would be in the term-level data constructor
            -- NameSpace.  See tests T10816, T23664, T24037.
            = Int -> Maybe Int
    forall a. a -> Maybe a
    Just Int
    1
            | NameSpace
    ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    tcName
            , NameSpace
    other_ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    dataName
            , Bool
    try_dc_first -- try data namespace before type/class namespace?
            = Int -> Maybe Int
    forall a. a -> Maybe a
    Just (-Int
    1)
            | Bool
    otherwise
            = Maybe Int
    forall a. Maybe a
    Nothing

          parent_prio :: Parent -> Int
          parent_prio :: Parent -> Int
    parent_prio (ParentIs Name
    other_parent)
            | Name
    other_parent Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    == Name
    wanted_parent = Int
    0
            | Bool
    otherwise                     = Int
    1
          parent_prio Parent
    NoParent              = Int
    0

    -- | Look something up in the Global Reader Environment.
    --
    -- The 'LookupGRE' argument specifies what to look up, and in particular
    -- whether there should there be any lee-way if the 'NameSpace's don't
    -- exactly match.
    lookupGRE :: GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    lookupGRE :: forall info.
    GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    lookupGRE GlobalRdrEnvX info
    env = \case
      LookupOccName OccName
    occ WhichGREs info
    which_gres ->
        case WhichGREs info
    which_gres of
          WhichGREs info
    SameNameSpace ->
            Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall (t :: * -> *) a. Foldable t => t [a] -> [a]
    concat (Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info])
    -> Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> OccName -> Maybe [GlobalRdrEltX info]
    forall a. OccEnv a -> OccName -> Maybe a
    lookupOccEnv GlobalRdrEnvX info
    env OccName
    occ
          rel :: WhichGREs info
    rel@(RelevantGREs{}) ->
            (GlobalRdrEltX info -> Bool)
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a. (a -> Bool) -> [a] -> [a]
    filter (WhichGREs GREInfo -> NameSpace -> GlobalRdrElt -> Bool
    greIsRelevant WhichGREs info
    WhichGREs GREInfo
    rel (OccName -> NameSpace
    occNameSpace OccName
    occ)) ([GlobalRdrEltX info] -> [GlobalRdrEltX info])
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $
              [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall (t :: * -> *) a. Foldable t => t [a] -> [a]
    concat ([[GlobalRdrEltX info]] -> [GlobalRdrEltX info])
    -> [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> OccName -> [[GlobalRdrEltX info]]
    forall a. OccEnv a -> OccName -> [a]
    lookupOccEnv_AllNameSpaces GlobalRdrEnvX info
    env OccName
    occ
      LookupRdrName RdrName
    rdr WhichGREs info
    rel ->
        RdrName -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall info.
    RdrName -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    pickGREs RdrName
    rdr ([GlobalRdrEltX info] -> [GlobalRdrEltX info])
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    forall info.
    GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    lookupGRE GlobalRdrEnvX info
    env (OccName -> WhichGREs info -> LookupGRE info
    forall info. OccName -> WhichGREs info -> LookupGRE info
    LookupOccName (RdrName -> OccName
    rdrNameOcc RdrName
    rdr) WhichGREs info
    rel)
      LookupExactName { lookupExactName :: forall info. LookupGRE info -> Name
    lookupExactName = Name
    nm
                      , lookInAllNameSpaces :: forall info. LookupGRE info -> Bool
    lookInAllNameSpaces = Bool
    all_ns } ->
          [ GlobalRdrEltX info
    gre | GlobalRdrEltX info
    gre <- [GlobalRdrEltX info]
    lkup, GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    == Name
    nm ]
        where
          occ :: OccName
    occ = Name -> OccName
    nameOccName Name
    nm
          lkup :: [GlobalRdrEltX info]
    lkup | Bool
    all_ns    = [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall (t :: * -> *) a. Foldable t => t [a] -> [a]
    concat ([[GlobalRdrEltX info]] -> [GlobalRdrEltX info])
    -> [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> OccName -> [[GlobalRdrEltX info]]
    forall a. OccEnv a -> OccName -> [a]
    lookupOccEnv_AllNameSpaces GlobalRdrEnvX info
    env OccName
    occ
               | Bool
    otherwise = [GlobalRdrEltX info]
    -> Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a. a -> Maybe a -> a
    fromMaybe [] (Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info])
    -> Maybe [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> OccName -> Maybe [GlobalRdrEltX info]
    forall a. OccEnv a -> OccName -> Maybe a
    lookupOccEnv GlobalRdrEnvX info
    env OccName
    occ
      LookupChildren OccName
    occ LookupChild
    which_child ->
        let ns :: NameSpace
    ns = OccName -> NameSpace
    occNameSpace OccName
    occ
            all_gres :: [GlobalRdrEltX info]
    all_gres = [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall (t :: * -> *) a. Foldable t => t [a] -> [a]
    concat ([[GlobalRdrEltX info]] -> [GlobalRdrEltX info])
    -> [[GlobalRdrEltX info]] -> [GlobalRdrEltX info]
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrEnvX info -> OccName -> [[GlobalRdrEltX info]]
    forall a. OccEnv a -> OccName -> [a]
    lookupOccEnv_AllNameSpaces GlobalRdrEnvX info
    env OccName
    occ
        in (GlobalRdrEltX info -> Maybe (Int, Int))
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall gre prio. Ord prio => (gre -> Maybe prio) -> [gre] -> [gre]
    highestPriorityGREs (LookupChild -> NameSpace -> GlobalRdrEltX info -> Maybe (Int, Int)
    forall info.
    LookupChild -> NameSpace -> GlobalRdrEltX info -> Maybe (Int, Int)
    childGREPriority LookupChild
    which_child NameSpace
    ns) [GlobalRdrEltX info]
    all_gres

    -- | Collect the 'GlobalRdrElt's with the highest priority according
    -- to the given function (lower value <=> higher priority).
    --
    -- This allows us to first look in e.g. the data 'NameSpace', and then fall back
    -- to the type/class 'NameSpace'.
    highestPriorityGREs :: forall gre prio
                        .  Ord prio
                        => (gre -> Maybe prio)
                          -- ^ priority function
                          -- lower value <=> higher priority
                        -> [gre] -> [gre]
    highestPriorityGREs :: forall gre prio. Ord prio => (gre -> Maybe prio) -> [gre] -> [gre]
    highestPriorityGREs gre -> Maybe prio
    priority [gre]
    gres =
      [NonEmpty (Arg prio gre)] -> [gre]
    take_highest_prio ([NonEmpty (Arg prio gre)] -> [gre])
    -> [NonEmpty (Arg prio gre)] -> [gre]
    forall a b. (a -> b) -> a -> b
    $ [Arg prio gre] -> [NonEmpty (Arg prio gre)]
    forall (f :: * -> *) a. (Foldable f, Eq a) => f a -> [NonEmpty a]
    NE.group ([Arg prio gre] -> [NonEmpty (Arg prio gre)])
    -> [Arg prio gre] -> [NonEmpty (Arg prio gre)]
    forall a b. (a -> b) -> a -> b
    $ [Arg prio gre] -> [Arg prio gre]
    forall a. Ord a => [a] -> [a]
    sort
        [ prio -> gre -> Arg prio gre
    forall a b. a -> b -> Arg a b
    S.Arg prio
    prio gre
    gre
        | gre
    gre <- [gre]
    gres
        , prio
    prio <- Maybe prio -> [prio]
    forall a. Maybe a -> [a]
    maybeToList (Maybe prio -> [prio]) -> Maybe prio -> [prio]
    forall a b. (a -> b) -> a -> b
    $ gre -> Maybe prio
    priority gre
    gre ]
      where
        take_highest_prio :: [NE.NonEmpty (S.Arg prio gre)] -> [gre]
        take_highest_prio :: [NonEmpty (Arg prio gre)] -> [gre]
    take_highest_prio [] = []
        take_highest_prio (NonEmpty (Arg prio gre)
    fs:[NonEmpty (Arg prio gre)]
    _) = (Arg prio gre -> gre) -> [Arg prio gre] -> [gre]
    forall a b. (a -> b) -> [a] -> [b]
    map (\ (S.Arg prio
    _ gre
    gre) -> gre
    gre) ([Arg prio gre] -> [gre]) -> [Arg prio gre] -> [gre]
    forall a b. (a -> b) -> a -> b
    $ NonEmpty (Arg prio gre) -> [Arg prio gre]
    forall a. NonEmpty a -> [a]
    NE.toList NonEmpty (Arg prio gre)
    fs
    {-# INLINEABLE highestPriorityGREs #-}

    -- | Look for precisely this 'Name' in the environment,
    -- in the __same 'NameSpace'__ as the 'Name'.
    --
    -- This tests whether it is in scope, ignoring anything
    -- else that might be in scope which doesn't have the same 'Unique'.
    lookupGRE_Name :: Outputable info => GlobalRdrEnvX info -> Name -> Maybe (GlobalRdrEltX info)
    lookupGRE_Name :: forall info.
    Outputable info =>
    GlobalRdrEnvX info -> Name -> Maybe (GlobalRdrEltX info)
    lookupGRE_Name GlobalRdrEnvX info
    env Name
    name =
      case GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    forall info.
    GlobalRdrEnvX info -> LookupGRE info -> [GlobalRdrEltX info]
    lookupGRE GlobalRdrEnvX info
    env (LookupExactName { lookupExactName :: Name
    lookupExactName = Name
    name
                                          , lookInAllNameSpaces :: Bool
    lookInAllNameSpaces = Bool
    False }) of
          []    -> Maybe (GlobalRdrEltX info)
    forall a. Maybe a
    Nothing
          [GlobalRdrEltX info
    gre] -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall a. a -> Maybe a
    Just GlobalRdrEltX info
    gre
          [GlobalRdrEltX info]
    gres  -> String -> SDoc -> Maybe (GlobalRdrEltX info)
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "lookupGRE_Name"
                            (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name SDoc -> SDoc -> SDoc
    forall doc. IsDoc doc => doc -> doc -> doc
    $$ OccName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (Name -> OccName
    nameOccName Name
    name) SDoc -> SDoc -> SDoc
    forall doc. IsDoc doc => doc -> doc -> doc
    $$ [GlobalRdrEltX info] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [GlobalRdrEltX info]
    gres)
                   -- See INVARIANT 1 on GlobalRdrEnv

    -- | Look for a particular record field selector in the environment.
    lookupGRE_FieldLabel :: GlobalRdrEnv -> FieldLabel -> Maybe FieldGlobalRdrElt
    lookupGRE_FieldLabel :: GlobalRdrEnv -> FieldLabel -> Maybe GlobalRdrElt
    lookupGRE_FieldLabel GlobalRdrEnv
    env FieldLabel
    fl =
      case GlobalRdrEnv -> Name -> Maybe GlobalRdrElt
    forall info.
    Outputable info =>
    GlobalRdrEnvX info -> Name -> Maybe (GlobalRdrEltX info)
    lookupGRE_Name GlobalRdrEnv
    env (FieldLabel -> Name
    flSelector FieldLabel
    fl) of
        Maybe GlobalRdrElt
    Nothing -> Maybe GlobalRdrElt
    forall a. Maybe a
    Nothing
        Just GlobalRdrElt
    gre ->
          Bool -> SDoc -> Maybe GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. HasCallStack => Bool -> SDoc -> a -> a
    assertPpr (GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE GlobalRdrElt
    gre)
            ([SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [ String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "lookupGre_FieldLabel:" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> FieldLabel -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr FieldLabel
    fl ]) (Maybe GlobalRdrElt -> Maybe GlobalRdrElt)
    -> Maybe GlobalRdrElt -> Maybe GlobalRdrElt
    forall a b. (a -> b) -> a -> b
    $
            GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. a -> Maybe a
    Just GlobalRdrElt
    gre

    getGRE_NameQualifier_maybes :: GlobalRdrEnv -> Name -> [Maybe [ModuleName]]
    -- Returns all the qualifiers by which 'x' is in scope
    -- Nothing means "the unqualified version is in scope"
    -- [] means the thing is not in scope at all
    getGRE_NameQualifier_maybes :: GlobalRdrEnv -> Name -> [Maybe [ModuleName]]
    getGRE_NameQualifier_maybes GlobalRdrEnv
    env Name
    name
      = case GlobalRdrEnv -> Name -> Maybe GlobalRdrElt
    forall info.
    Outputable info =>
    GlobalRdrEnvX info -> Name -> Maybe (GlobalRdrEltX info)
    lookupGRE_Name GlobalRdrEnv
    env Name
    name of
          Just GlobalRdrElt
    gre -> [GlobalRdrElt -> Maybe [ModuleName]
    forall {info}. GlobalRdrEltX info -> Maybe [ModuleName]
    qualifier_maybe GlobalRdrElt
    gre]
          Maybe GlobalRdrElt
    Nothing  -> []
      where
        qualifier_maybe :: GlobalRdrEltX info -> Maybe [ModuleName]
    qualifier_maybe (GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
          | Bool
    lcl       = Maybe [ModuleName]
    forall a. Maybe a
    Nothing
          | Bool
    otherwise = [ModuleName] -> Maybe [ModuleName]
    forall a. a -> Maybe a
    Just ([ModuleName] -> Maybe [ModuleName])
    -> [ModuleName] -> Maybe [ModuleName]
    forall a b. (a -> b) -> a -> b
    $ (ImportSpec -> ModuleName) -> [ImportSpec] -> [ModuleName]
    forall a b. (a -> b) -> [a] -> [b]
    map (ImpDeclSpec -> ModuleName
    is_as (ImpDeclSpec -> ModuleName)
    -> (ImportSpec -> ImpDeclSpec) -> ImportSpec -> ModuleName
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . ImportSpec -> ImpDeclSpec
    is_decl) (Bag ImportSpec -> [ImportSpec]
    forall a. Bag a -> [a]
    bagToList Bag ImportSpec
    iss)

    -- | Is this 'GlobalRdrElt' defined locally?
    isLocalGRE :: GlobalRdrEltX info -> Bool
    isLocalGRE :: forall info. GlobalRdrEltX info -> Bool
    isLocalGRE (GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl }) = Bool
    lcl

    -- | Is this 'GlobalRdrElt' imported?
    --
    -- Not just the negation of 'isLocalGRE', because it might be an Exact or
    -- Orig name reference. See Note [GlobalRdrElt provenance].
    isImportedGRE :: GlobalRdrEltX info -> Bool
    isImportedGRE :: forall info. GlobalRdrEltX info -> Bool
    isImportedGRE (GRE { gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    imps }) = Bool -> Bool
    not (Bool -> Bool) -> Bool -> Bool
    forall a b. (a -> b) -> a -> b
    $ Bag ImportSpec -> Bool
    forall a. Bag a -> Bool
    isEmptyBag Bag ImportSpec
    imps

    -- | Is this a record field GRE?
    --
    -- Important: does /not/ consult the 'GreInfo' field.
    isRecFldGRE :: GlobalRdrEltX info -> Bool
    isRecFldGRE :: forall info. GlobalRdrEltX info -> Bool
    isRecFldGRE (GRE { gre_name :: forall info. GlobalRdrEltX info -> Name
    gre_name = Name
    nm }) = Name -> Bool
    isFieldName Name
    nm

    isDuplicateRecFldGRE :: GlobalRdrElt -> Bool
    -- ^ Is this a record field defined with DuplicateRecordFields?
    isDuplicateRecFldGRE :: GlobalRdrElt -> Bool
    isDuplicateRecFldGRE =
        Bool -> (FieldLabel -> Bool) -> Maybe FieldLabel -> Bool
    forall b a. b -> (a -> b) -> Maybe a -> b
    maybe Bool
    False ((DuplicateRecordFields
    DuplicateRecordFields DuplicateRecordFields -> DuplicateRecordFields -> Bool
    forall a. Eq a => a -> a -> Bool
    ==) (DuplicateRecordFields -> Bool)
    -> (FieldLabel -> DuplicateRecordFields) -> FieldLabel -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . FieldLabel -> DuplicateRecordFields
    flHasDuplicateRecordFields) (Maybe FieldLabel -> Bool)
    -> (GlobalRdrElt -> Maybe FieldLabel) -> GlobalRdrElt -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrElt -> Maybe FieldLabel
    greFieldLabel_maybe

    isNoFieldSelectorGRE :: GlobalRdrElt -> Bool
    -- ^ Is this a record field defined with NoFieldSelectors?
    -- (See Note [NoFieldSelectors] in GHC.Rename.Env)
    isNoFieldSelectorGRE :: GlobalRdrElt -> Bool
    isNoFieldSelectorGRE =
        Bool -> (FieldLabel -> Bool) -> Maybe FieldLabel -> Bool
    forall b a. b -> (a -> b) -> Maybe a -> b
    maybe Bool
    False ((FieldSelectors
    NoFieldSelectors FieldSelectors -> FieldSelectors -> Bool
    forall a. Eq a => a -> a -> Bool
    ==) (FieldSelectors -> Bool)
    -> (FieldLabel -> FieldSelectors) -> FieldLabel -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . FieldLabel -> FieldSelectors
    flHasFieldSelector) (Maybe FieldLabel -> Bool)
    -> (GlobalRdrElt -> Maybe FieldLabel) -> GlobalRdrElt -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrElt -> Maybe FieldLabel
    greFieldLabel_maybe

    isFieldSelectorGRE :: GlobalRdrElt -> Bool
    -- ^ Is this a record field defined with FieldSelectors?
    -- (See Note [NoFieldSelectors] in GHC.Rename.Env)
    isFieldSelectorGRE :: GlobalRdrElt -> Bool
    isFieldSelectorGRE =
        Bool -> (FieldLabel -> Bool) -> Maybe FieldLabel -> Bool
    forall b a. b -> (a -> b) -> Maybe a -> b
    maybe Bool
    False ((FieldSelectors
    FieldSelectors FieldSelectors -> FieldSelectors -> Bool
    forall a. Eq a => a -> a -> Bool
    ==) (FieldSelectors -> Bool)
    -> (FieldLabel -> FieldSelectors) -> FieldLabel -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . FieldLabel -> FieldSelectors
    flHasFieldSelector) (Maybe FieldLabel -> Bool)
    -> (GlobalRdrElt -> Maybe FieldLabel) -> GlobalRdrElt -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrElt -> Maybe FieldLabel
    greFieldLabel_maybe

    greFieldLabel_maybe :: GlobalRdrElt -> Maybe FieldLabel
    -- ^ Returns the field label of this GRE, if it has one
    greFieldLabel_maybe :: GlobalRdrElt -> Maybe FieldLabel
    greFieldLabel_maybe = (GlobalRdrElt -> FieldLabel)
    -> Maybe GlobalRdrElt -> Maybe FieldLabel
    forall a b. (a -> b) -> Maybe a -> Maybe b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap HasDebugCallStack => GlobalRdrElt -> FieldLabel
    GlobalRdrElt -> FieldLabel
    fieldGRELabel (Maybe GlobalRdrElt -> Maybe FieldLabel)
    -> (GlobalRdrElt -> Maybe GlobalRdrElt)
    -> GlobalRdrElt
    -> Maybe FieldLabel
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GlobalRdrElt -> Maybe GlobalRdrElt
    fieldGRE_maybe

    unQualOK :: GlobalRdrEltX info -> Bool
    -- ^ Test if an unqualified version of this thing would be in scope
    unQualOK :: forall info. GlobalRdrEltX info -> Bool
    unQualOK (GRE {gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
      | Bool
    lcl = Bool
    True
      | Bool
    otherwise = (ImportSpec -> Bool) -> Bag ImportSpec -> Bool
    forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
    any ImportSpec -> Bool
    unQualSpecOK Bag ImportSpec
    iss

    {- Note [GRE filtering]
    ~~~~~~~~~~~~~~~~~~~~~~~
    (pickGREs rdr gres) takes a list of GREs which have the same OccName
    as 'rdr', say "x".  It does two things:

    (a) filters the GREs to a subset that are in scope
        * Qualified,   as 'M.x'  if want_qual    is Qual M _
        * Unqualified, as 'x'    if want_unqual  is Unqual _

    (b) for that subset, filter the provenance field (gre_lcl and gre_imp)
        to ones that brought it into scope qualified or unqualified resp.

    Example:
          module A ( f ) where
          import qualified Foo( f )
          import Baz( f )
          f = undefined

    Let's suppose that Foo.f and Baz.f are the same entity really, but the local
    'f' is different, so there will be two GREs matching "f":
       gre1:  gre_lcl = True,  gre_imp = []
       gre2:  gre_lcl = False, gre_imp = [ imported from Foo, imported from Bar ]

    The use of "f" in the export list is ambiguous because it's in scope
    from the local def and the import Baz(f); but *not* the import qualified Foo.
    pickGREs returns two GRE
       gre1:   gre_lcl = True,  gre_imp = []
       gre2:   gre_lcl = False, gre_imp = [ imported from Bar ]

    Now the "ambiguous occurrence" message can correctly report how the
    ambiguity arises.
    -}

    pickGREs :: RdrName -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    -- ^ Takes a list of GREs which have the right OccName 'x'
    -- Pick those GREs that are in scope
    --    * Qualified,   as 'M.x'  if want_qual    is Qual M _
    --    * Unqualified, as 'x'    if want_unqual  is Unqual _
    --
    -- Return each such GRE, with its ImportSpecs filtered, to reflect
    -- how it is in scope qualified or unqualified respectively.
    -- See Note [GRE filtering]
    pickGREs :: forall info.
    RdrName -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    pickGREs (Unqual {})  [GlobalRdrEltX info]
    gres = (GlobalRdrEltX info -> Maybe (GlobalRdrEltX info))
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall info. GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickUnqualGRE     [GlobalRdrEltX info]
    gres
    pickGREs (Qual ModuleName
    mod OccName
    _) [GlobalRdrEltX info]
    gres = (GlobalRdrEltX info -> Maybe (GlobalRdrEltX info))
    -> [GlobalRdrEltX info] -> [GlobalRdrEltX info]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe (ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall info.
    ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickQualGRE ModuleName
    mod) [GlobalRdrEltX info]
    gres
    pickGREs RdrName
    _            [GlobalRdrEltX info]
    _    = []  -- I don't think this actually happens

    pickUnqualGRE :: GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickUnqualGRE :: forall info. GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickUnqualGRE gre :: GlobalRdrEltX info
    gre@(GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
      | Bool -> Bool
    not Bool
    lcl, Bag ImportSpec -> Bool
    forall a. Bag a -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null Bag ImportSpec
    iss' = Maybe (GlobalRdrEltX info)
    forall a. Maybe a
    Nothing
      | Bool
    otherwise          = GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall a. a -> Maybe a
    Just (GlobalRdrEltX info
    gre { gre_imp = iss' })
      where
        iss' :: Bag ImportSpec
    iss' = (ImportSpec -> Bool) -> Bag ImportSpec -> Bag ImportSpec
    forall a. (a -> Bool) -> Bag a -> Bag a
    filterBag ImportSpec -> Bool
    unQualSpecOK Bag ImportSpec
    iss

    pickQualGRE :: ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickQualGRE :: forall info.
    ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickQualGRE ModuleName
    mod gre :: GlobalRdrEltX info
    gre@(GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
      | Bool -> Bool
    not Bool
    lcl', Bag ImportSpec -> Bool
    forall a. Bag a -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null Bag ImportSpec
    iss' = Maybe (GlobalRdrEltX info)
    forall a. Maybe a
    Nothing
      | Bool
    otherwise           = GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall a. a -> Maybe a
    Just (GlobalRdrEltX info
    gre { gre_lcl = lcl', gre_imp = iss' })
      where
        iss' :: Bag ImportSpec
    iss' = (ImportSpec -> Bool) -> Bag ImportSpec -> Bag ImportSpec
    forall a. (a -> Bool) -> Bag a -> Bag a
    filterBag (ModuleName -> ImportSpec -> Bool
    qualSpecOK ModuleName
    mod) Bag ImportSpec
    iss
        lcl' :: Bool
    lcl' = Bool
    lcl Bool -> Bool -> Bool
    && ModuleName -> Bool
    name_is_from ModuleName
    mod

        name_is_from :: ModuleName -> Bool
        name_is_from :: ModuleName -> Bool
    name_is_from ModuleName
    mod = case GlobalRdrEltX info -> Maybe Module
    forall info. GlobalRdrEltX info -> Maybe Module
    greDefinitionModule GlobalRdrEltX info
    gre of
                             Just Module
    n_mod -> Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName Module
    n_mod ModuleName -> ModuleName -> Bool
    forall a. Eq a => a -> a -> Bool
    == ModuleName
    mod
                             Maybe Module
    Nothing    -> Bool
    False

    pickGREsModExp :: ModuleName -> [GlobalRdrEltX info] -> [(GlobalRdrEltX info,GlobalRdrEltX info)]
    -- ^ Pick GREs that are in scope *both* qualified *and* unqualified
    -- Return each GRE that is, as a pair
    --    (qual_gre, unqual_gre)
    -- These two GREs are the original GRE with imports filtered to express how
    -- it is in scope qualified an unqualified respectively
    --
    -- Used only for the 'module M' item in export list;
    --   see 'GHC.Tc.Gen.Export.exports_from_avail'
    pickGREsModExp :: forall info.
    ModuleName
    -> [GlobalRdrEltX info]
    -> [(GlobalRdrEltX info, GlobalRdrEltX info)]
    pickGREsModExp ModuleName
    mod [GlobalRdrEltX info]
    gres = (GlobalRdrEltX info
     -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info))
    -> [GlobalRdrEltX info]
    -> [(GlobalRdrEltX info, GlobalRdrEltX info)]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe (ModuleName
    -> GlobalRdrEltX info
    -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    forall info.
    ModuleName
    -> GlobalRdrEltX info
    -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    pickBothGRE ModuleName
    mod) [GlobalRdrEltX info]
    gres

    -- | isBuiltInSyntax filter out names for built-in syntax They
    -- just clutter up the environment (esp tuples), and the
    -- parser will generate Exact RdrNames for them, so the
    -- cluttered envt is no use.  Really, it's only useful for
    -- GHC.Base and GHC.Tuple.
    pickBothGRE :: ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    pickBothGRE :: forall info.
    ModuleName
    -> GlobalRdrEltX info
    -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    pickBothGRE ModuleName
    mod GlobalRdrEltX info
    gre
      | Name -> Bool
    isBuiltInSyntax (GlobalRdrEltX info -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrEltX info
    gre)
      = Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    forall a. Maybe a
    Nothing
      | Just GlobalRdrEltX info
    gre1 <- ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall info.
    ModuleName -> GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickQualGRE ModuleName
    mod GlobalRdrEltX info
    gre
      , Just GlobalRdrEltX info
    gre2 <- GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    forall info. GlobalRdrEltX info -> Maybe (GlobalRdrEltX info)
    pickUnqualGRE   GlobalRdrEltX info
    gre
      = (GlobalRdrEltX info, GlobalRdrEltX info)
    -> Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    forall a. a -> Maybe a
    Just (GlobalRdrEltX info
    gre1, GlobalRdrEltX info
    gre2)
      | Bool
    otherwise
      = Maybe (GlobalRdrEltX info, GlobalRdrEltX info)
    forall a. Maybe a
    Nothing

    -- Building GlobalRdrEnvs

    plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    plusGlobalRdrEnv GlobalRdrEnv
    env1 GlobalRdrEnv
    env2 = ([GlobalRdrElt] -> [GlobalRdrElt] -> [GlobalRdrElt])
    -> GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    forall a. (a -> a -> a) -> OccEnv a -> OccEnv a -> OccEnv a
    plusOccEnv_C ((GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt])
    -> [GlobalRdrElt] -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a b. (a -> b -> b) -> b -> [a] -> b
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE) GlobalRdrEnv
    env1 GlobalRdrEnv
    env2

    mkGlobalRdrEnv :: [GlobalRdrElt] -> GlobalRdrEnv
    mkGlobalRdrEnv :: [GlobalRdrElt] -> GlobalRdrEnv
    mkGlobalRdrEnv [GlobalRdrElt]
    gres
      = (GlobalRdrElt -> GlobalRdrEnv -> GlobalRdrEnv)
    -> GlobalRdrEnv -> [GlobalRdrElt] -> GlobalRdrEnv
    forall a b. (a -> b -> b) -> b -> [a] -> b
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr GlobalRdrElt -> GlobalRdrEnv -> GlobalRdrEnv
    add GlobalRdrEnv
    forall info. GlobalRdrEnvX info
    emptyGlobalRdrEnv [GlobalRdrElt]
    gres
      where
        add :: GlobalRdrElt -> GlobalRdrEnv -> GlobalRdrEnv
    add GlobalRdrElt
    gre GlobalRdrEnv
    env = (GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt])
    -> (GlobalRdrElt -> [GlobalRdrElt])
    -> GlobalRdrEnv
    -> OccName
    -> GlobalRdrElt
    -> GlobalRdrEnv
    forall a b.
    (a -> b -> b) -> (a -> b) -> OccEnv b -> OccName -> a -> OccEnv b
    extendOccEnv_Acc GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE GlobalRdrElt -> [GlobalRdrElt]
    forall a. a -> [a]
    Utils.singleton GlobalRdrEnv
    env
                                       (GlobalRdrElt -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName GlobalRdrElt
    gre)
                                       GlobalRdrElt
    gre

    insertGRE :: GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE :: GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE GlobalRdrElt
    new_g [] = [GlobalRdrElt
    new_g]
    insertGRE GlobalRdrElt
    new_g (GlobalRdrElt
    old_g : [GlobalRdrElt]
    old_gs)
            | GlobalRdrElt -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrElt
    new_g Name -> Name -> Bool
    forall a. Eq a => a -> a -> Bool
    == GlobalRdrElt -> Name
    forall info. GlobalRdrEltX info -> Name
    greName GlobalRdrElt
    old_g
            = GlobalRdrElt
    new_g GlobalRdrElt -> GlobalRdrElt -> GlobalRdrElt
    `plusGRE` GlobalRdrElt
    old_g GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a. a -> [a] -> [a]
    : [GlobalRdrElt]
    old_gs
            | Bool
    otherwise
            = GlobalRdrElt
    old_g GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a. a -> [a] -> [a]
    : GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE GlobalRdrElt
    new_g [GlobalRdrElt]
    old_gs

    plusGRE :: GlobalRdrElt -> GlobalRdrElt -> GlobalRdrElt
    -- Used when the gre_name fields match
    plusGRE :: GlobalRdrElt -> GlobalRdrElt -> GlobalRdrElt
    plusGRE GlobalRdrElt
    g1 GlobalRdrElt
    g2
      = GRE { gre_name :: Name
    gre_name = GlobalRdrElt -> Name
    forall info. GlobalRdrEltX info -> Name
    gre_name GlobalRdrElt
    g1
            , gre_lcl :: Bool
    gre_lcl  = GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    gre_lcl GlobalRdrElt
    g1 Bool -> Bool -> Bool
    || GlobalRdrElt -> Bool
    forall info. GlobalRdrEltX info -> Bool
    gre_lcl GlobalRdrElt
    g2
            , gre_imp :: Bag ImportSpec
    gre_imp  = GlobalRdrElt -> Bag ImportSpec
    forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp GlobalRdrElt
    g1 Bag ImportSpec -> Bag ImportSpec -> Bag ImportSpec
    forall a. Bag a -> Bag a -> Bag a
    `unionBags` GlobalRdrElt -> Bag ImportSpec
    forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp GlobalRdrElt
    g2
            , gre_par :: Parent
    gre_par  = GlobalRdrElt -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par GlobalRdrElt
    g1 Parent -> Parent -> Parent
    `plusParent` GlobalRdrElt -> Parent
    forall info. GlobalRdrEltX info -> Parent
    gre_par GlobalRdrElt
    g2
            , gre_info :: GREInfo
    gre_info = GlobalRdrElt -> GREInfo
    forall info. GlobalRdrEltX info -> info
    gre_info GlobalRdrElt
    g1 GREInfo -> GREInfo -> GREInfo
    `plusGREInfo` GlobalRdrElt -> GREInfo
    forall info. GlobalRdrEltX info -> info
    gre_info GlobalRdrElt
    g2 }

    transformGREs :: (GlobalRdrElt -> GlobalRdrElt)
                  -> [OccName]
                  -> GlobalRdrEnv -> GlobalRdrEnv
    -- ^ Apply a transformation function to the GREs for these OccNames
    transformGREs :: (GlobalRdrElt -> GlobalRdrElt)
    -> [OccName] -> GlobalRdrEnv -> GlobalRdrEnv
    transformGREs GlobalRdrElt -> GlobalRdrElt
    trans_gre [OccName]
    occs GlobalRdrEnv
    rdr_env
      = (OccName -> GlobalRdrEnv -> GlobalRdrEnv)
    -> GlobalRdrEnv -> [OccName] -> GlobalRdrEnv
    forall a b. (a -> b -> b) -> b -> [a] -> b
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr OccName -> GlobalRdrEnv -> GlobalRdrEnv
    trans GlobalRdrEnv
    rdr_env [OccName]
    occs
      where
        trans :: OccName -> GlobalRdrEnv -> GlobalRdrEnv
    trans OccName
    occ GlobalRdrEnv
    env
          = case GlobalRdrEnv -> OccName -> Maybe [GlobalRdrElt]
    forall a. OccEnv a -> OccName -> Maybe a
    lookupOccEnv GlobalRdrEnv
    env OccName
    occ of
               Just [GlobalRdrElt]
    gres -> GlobalRdrEnv -> OccName -> [GlobalRdrElt] -> GlobalRdrEnv
    forall a. OccEnv a -> OccName -> a -> OccEnv a
    extendOccEnv GlobalRdrEnv
    env OccName
    occ ((GlobalRdrElt -> GlobalRdrElt) -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a b. (a -> b) -> [a] -> [b]
    map GlobalRdrElt -> GlobalRdrElt
    trans_gre [GlobalRdrElt]
    gres)
               Maybe [GlobalRdrElt]
    Nothing   -> GlobalRdrEnv
    env

    extendGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrElt -> GlobalRdrEnv
    extendGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrElt -> GlobalRdrEnv
    extendGlobalRdrEnv GlobalRdrEnv
    env GlobalRdrElt
    gre
      = (GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt])
    -> (GlobalRdrElt -> [GlobalRdrElt])
    -> GlobalRdrEnv
    -> OccName
    -> GlobalRdrElt
    -> GlobalRdrEnv
    forall a b.
    (a -> b -> b) -> (a -> b) -> OccEnv b -> OccName -> a -> OccEnv b
    extendOccEnv_Acc GlobalRdrElt -> [GlobalRdrElt] -> [GlobalRdrElt]
    insertGRE GlobalRdrElt -> [GlobalRdrElt]
    forall a. a -> [a]
    Utils.singleton GlobalRdrEnv
    env
                         (GlobalRdrElt -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName GlobalRdrElt
    gre) GlobalRdrElt
    gre

    {- Note [GlobalRdrEnv shadowing]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Before adding new names to the GlobalRdrEnv we nuke some existing entries;
    this is "shadowing".  The actual work is done by GHC.Types.Name.Reader.shadowNames.
    Suppose

       env' = shadowNames env { f } `extendGlobalRdrEnv` { M.f }

    Then:
       * Looking up (Unqual f) in env' should succeed, returning M.f,
         even if env contains existing unqualified bindings for f.
         They are shadowed

       * Looking up (Qual M.f) in env' should succeed, returning M.f

       * Looking up (Qual X.f) in env', where X /= M, should be the same as
         looking up (Qual X.f) in env.

         That is, shadowNames does /not/ delete earlier qualified bindings

    There are two reasons for shadowing:

    * The GHCi REPL

      - Ids bought into scope on the command line (eg let x = True) have
        External Names, like Ghci4.x.  We want a new binding for 'x' (say)
        to override the existing binding for 'x'.  Example:

               ghci> :load M    -- Brings `x` and `M.x` into scope
               ghci> x
               ghci> "Hello"
               ghci> M.x
               ghci> "hello"
               ghci> let x = True  -- Shadows `x`
               ghci> x             -- The locally bound `x`
                                   -- NOT an ambiguous reference
               ghci> True
               ghci> M.x           -- M.x is still in scope!
               ghci> "Hello"

        So when we add `x = True` we must not delete the `M.x` from the
        `GlobalRdrEnv`; rather we just want to make it "qualified only";
        hence the `set_qual` in `shadowNames`.  See also Note
        [Interactively-bound Ids in GHCi] in GHC.Runtime.Context

      - Data types also have External Names, like Ghci4.T; but we still want
        'T' to mean the newly-declared 'T', not an old one.

    * Nested Template Haskell declaration brackets
      See Note [Top-level Names in Template Haskell decl quotes] in GHC.Rename.Names

      Consider a TH decl quote:
          module M where
            f x = h [d| f = ...f...M.f... |]
      We must shadow the outer unqualified binding of 'f', else we'll get
      a complaint when extending the GlobalRdrEnv, saying that there are
      two bindings for 'f'.  There are several tricky points:

        - This shadowing applies even if the binding for 'f' is in a
          where-clause, and hence is in the *local* RdrEnv not the *global*
          RdrEnv.  This is done in lcl_env_TH in extendGlobalRdrEnvRn.

        - The External Name M.f from the enclosing module must certainly
          still be available.  So we don't nuke it entirely; we just make
          it seem like qualified import.

        - We only shadow *External* names (which come from the main module),
          or from earlier GHCi commands. Do not shadow *Internal* names
          because in the bracket
              [d| class C a where f :: a
                  f = 4 |]
          rnSrcDecls will first call extendGlobalRdrEnvRn with C[f] from the
          class decl, and *separately* extend the envt with the value binding.
          At that stage, the class op 'f' will have an Internal name.

    Wrinkle [Shadowing namespaces]

      In the following GHCi session:

        > data A = MkA { foo :: Int }
        > foo = False
        > bar = foo

      We expect the variable 'foo' to shadow the record field 'foo', even though
      they are in separate namespaces, so that the occurrence of 'foo' in the body
      of 'bar' is not ambiguous.

    -}

    shadowNames :: Bool -- ^ discard names that are only available qualified?
                -> GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    -- Remove certain old GREs that share the same OccName as this new Name.
    -- See Note [GlobalRdrEnv shadowing] for details
    shadowNames :: Bool -> GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    shadowNames Bool
    drop_only_qualified GlobalRdrEnv
    env GlobalRdrEnv
    new_gres = (UniqFM NameSpace [GlobalRdrElt]
     -> UniqFM NameSpace [GlobalRdrElt]
     -> UniqFM NameSpace [GlobalRdrElt])
    -> GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
    forall a b.
    (UniqFM NameSpace a -> UniqFM NameSpace b -> UniqFM NameSpace a)
    -> OccEnv a -> OccEnv b -> OccEnv a
    minusOccEnv_C_Ns UniqFM NameSpace [GlobalRdrElt]
    -> UniqFM NameSpace [GlobalRdrElt]
    -> UniqFM NameSpace [GlobalRdrElt]
    do_shadowing GlobalRdrEnv
    env GlobalRdrEnv
    new_gres
      where

        do_shadowing :: UniqFM NameSpace [GlobalRdrElt]
                     -> UniqFM NameSpace [GlobalRdrElt]
                     -> UniqFM NameSpace [GlobalRdrElt]
        do_shadowing :: UniqFM NameSpace [GlobalRdrElt]
    -> UniqFM NameSpace [GlobalRdrElt]
    -> UniqFM NameSpace [GlobalRdrElt]
    do_shadowing UniqFM NameSpace [GlobalRdrElt]
    olds UniqFM NameSpace [GlobalRdrElt]
    news =
          -- Start off by accumulating all 'NameSpace's shadowed
          -- by the entire collection of new GREs.
          let shadowed_gres :: ShadowedGREs
              shadowed_gres :: ShadowedGREs
    shadowed_gres =
                ([GlobalRdrElt] -> ShadowedGREs -> ShadowedGREs)
    -> ShadowedGREs -> UniqFM NameSpace [GlobalRdrElt] -> ShadowedGREs
    forall {k} elt a (key :: k).
    (elt -> a -> a) -> a -> UniqFM key elt -> a
    nonDetFoldUFM (\ [GlobalRdrElt]
    gres ShadowedGREs
    shads -> (GlobalRdrElt -> ShadowedGREs) -> [GlobalRdrElt] -> ShadowedGREs
    forall m a. Monoid m => (a -> m) -> [a] -> m
    forall (t :: * -> *) m a.
    (Foldable t, Monoid m) =>
    (a -> m) -> t a -> m
    foldMap GlobalRdrElt -> ShadowedGREs
    greShadowedNameSpaces [GlobalRdrElt]
    gres ShadowedGREs -> ShadowedGREs -> ShadowedGREs
    forall a. Semigroup a => a -> a -> a
    S.<> ShadowedGREs
    shads)
                  ShadowedGREs
    forall a. Monoid a => a
    mempty UniqFM NameSpace [GlobalRdrElt]
    news

          -- Then shadow the old 'GlobalRdrElt's, now that we know which 'NameSpace's
          -- should be shadowed.
              shadow_list :: Unique -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
              shadow_list :: Unique -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    shadow_list Unique
    old_ns [GlobalRdrElt]
    old_gres =
                case Unique -> ShadowedGREs -> IsShadowed
    namespace_is_shadowed Unique
    old_ns ShadowedGREs
    shadowed_gres of
                  IsShadowed
    IsNotShadowed -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    forall a. a -> Maybe a
    Just [GlobalRdrElt]
    old_gres
                  IsShadowed
    IsShadowed    -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    forall a. [a] -> Maybe [a]
    guard_nonEmpty ([GlobalRdrElt] -> Maybe [GlobalRdrElt])
    -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    forall a b. (a -> b) -> a -> b
    $ (GlobalRdrElt -> Maybe GlobalRdrElt)
    -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe GlobalRdrElt -> Maybe GlobalRdrElt
    shadow [GlobalRdrElt]
    old_gres
                  IsShadowed
    IsShadowedIfFieldSelector ->
                    [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    forall a. [a] -> Maybe [a]
    guard_nonEmpty ([GlobalRdrElt] -> Maybe [GlobalRdrElt])
    -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    forall a b. (a -> b) -> a -> b
    $
                    (GlobalRdrElt -> Maybe GlobalRdrElt)
    -> [GlobalRdrElt] -> [GlobalRdrElt]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe (\ GlobalRdrElt
    old_gre -> if GlobalRdrElt -> Bool
    isFieldSelectorGRE GlobalRdrElt
    old_gre then GlobalRdrElt -> Maybe GlobalRdrElt
    shadow GlobalRdrElt
    old_gre else GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. a -> Maybe a
    Just GlobalRdrElt
    old_gre)
                      [GlobalRdrElt]
    old_gres

          -- Now do all of the shadowing in a single go. This avoids traversing
          -- the old GlobalRdrEnv multiple times over.
          in (Unique -> [GlobalRdrElt] -> Maybe [GlobalRdrElt])
    -> UniqFM NameSpace [GlobalRdrElt]
    -> UniqFM NameSpace [GlobalRdrElt]
    forall {k} elt1 elt2 (key :: k).
    (Unique -> elt1 -> Maybe elt2)
    -> UniqFM key elt1 -> UniqFM key elt2
    mapMaybeWithKeyUFM Unique -> [GlobalRdrElt] -> Maybe [GlobalRdrElt]
    shadow_list UniqFM NameSpace [GlobalRdrElt]
    olds

        guard_nonEmpty :: [a] -> Maybe [a]
        guard_nonEmpty :: forall a. [a] -> Maybe [a]
    guard_nonEmpty [a]
    xs | [a] -> Bool
    forall a. [a] -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null [a]
    xs   = Maybe [a]
    forall a. Maybe a
    Nothing
                          | Bool
    otherwise = [a] -> Maybe [a]
    forall a. a -> Maybe a
    Just [a]
    xs

        -- Shadow a single GRE, by either qualifying it or removing it entirely.
        shadow :: GlobalRdrElt-> Maybe GlobalRdrElt
        shadow :: GlobalRdrElt -> Maybe GlobalRdrElt
    shadow old_gre :: GlobalRdrElt
    old_gre@(GRE { gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss }) =
          case GlobalRdrElt -> Maybe Module
    forall info. GlobalRdrEltX info -> Maybe Module
    greDefinitionModule GlobalRdrElt
    old_gre of
            Maybe Module
    Nothing -> GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. a -> Maybe a
    Just GlobalRdrElt
    old_gre   -- Old name is Internal; do not shadow
            Just Module
    old_mod
               |  Bag ImportSpec -> Bool
    forall a. Bag a -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null Bag ImportSpec
    iss'            -- Nothing remains
               Bool -> Bool -> Bool
    || Bool
    drop_only_qualified
               -> Maybe GlobalRdrElt
    forall a. Maybe a
    Nothing

               | Bool
    otherwise
               -> GlobalRdrElt -> Maybe GlobalRdrElt
    forall a. a -> Maybe a
    Just (GlobalRdrElt
    old_gre { gre_lcl = False, gre_imp = iss' })

               where
                 iss' :: Bag ImportSpec
    iss' = Bag ImportSpec
    lcl_imp Bag ImportSpec -> Bag ImportSpec -> Bag ImportSpec
    forall a. Bag a -> Bag a -> Bag a
    `unionBags` (ImportSpec -> ImportSpec) -> Bag ImportSpec -> Bag ImportSpec
    forall a b. (a -> b) -> Bag a -> Bag b
    mapBag ImportSpec -> ImportSpec
    set_qual Bag ImportSpec
    iss
                 lcl_imp :: Bag ImportSpec
    lcl_imp | Bool
    lcl       = ImportSpec -> Bag ImportSpec
    forall a. a -> Bag a
    unitBag (ImportSpec -> Bag ImportSpec) -> ImportSpec -> Bag ImportSpec
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrElt -> Module -> ImportSpec
    forall {info}. GlobalRdrEltX info -> Module -> ImportSpec
    mk_fake_imp_spec GlobalRdrElt
    old_gre Module
    old_mod
                         | Bool
    otherwise = Bag ImportSpec
    forall a. Bag a
    emptyBag

        mk_fake_imp_spec :: GlobalRdrEltX info -> Module -> ImportSpec
    mk_fake_imp_spec GlobalRdrEltX info
    old_gre Module
    old_mod    -- Urgh!
          = ImpDeclSpec -> ImpItemSpec -> ImportSpec
    ImpSpec ImpDeclSpec
    id_spec ImpItemSpec
    ImpAll
          where
            old_mod_name :: ModuleName
    old_mod_name = Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName Module
    old_mod
            id_spec :: ImpDeclSpec
    id_spec      = ImpDeclSpec { is_mod :: Module
    is_mod = Module
    old_mod
                                       , is_as :: ModuleName
    is_as = ModuleName
    old_mod_name
                                       , is_qual :: Bool
    is_qual = Bool
    True
                                       , is_dloc :: SrcSpan
    is_dloc = GlobalRdrEltX info -> SrcSpan
    forall info. GlobalRdrEltX info -> SrcSpan
    greDefinitionSrcSpan GlobalRdrEltX info
    old_gre }

        set_qual :: ImportSpec -> ImportSpec
        set_qual :: ImportSpec -> ImportSpec
    set_qual ImportSpec
    is = ImportSpec
    is { is_decl = (is_decl is) { is_qual = True } }

    -- | @greClashesWith new_gre old_gre@ computes whether @new_gre@ clashes
    -- with @old_gre@ (assuming they both have the same underlying 'occNameFS').
    greClashesWith :: GlobalRdrElt -> (GlobalRdrElt -> Bool)
    greClashesWith :: GlobalRdrElt -> GlobalRdrElt -> Bool
    greClashesWith GlobalRdrElt
    new_gre GlobalRdrElt
    old_gre =
      GlobalRdrElt
    old_gre GlobalRdrElt -> ShadowedGREs -> Bool
    `greIsShadowed` GlobalRdrElt -> ShadowedGREs
    greShadowedNameSpaces GlobalRdrElt
    new_gre

    -- | Is the given 'GlobalRdrElt' shadowed, as specified by the 'ShadowedNameSpace's?
    greIsShadowed :: GlobalRdrElt -> ShadowedGREs -> Bool
    greIsShadowed :: GlobalRdrElt -> ShadowedGREs -> Bool
    greIsShadowed GlobalRdrElt
    old_gre ShadowedGREs
    shadowed =
      case NameSpace -> Unique
    forall a. Uniquable a => a -> Unique
    getUnique NameSpace
    old_ns Unique -> ShadowedGREs -> IsShadowed
    `namespace_is_shadowed` ShadowedGREs
    shadowed of
        IsShadowed
    IsShadowed                -> Bool
    True
        IsShadowed
    IsNotShadowed             -> Bool
    False
        IsShadowed
    IsShadowedIfFieldSelector -> GlobalRdrElt -> Bool
    isFieldSelectorGRE GlobalRdrElt
    old_gre
      where
        old_ns :: NameSpace
    old_ns = OccName -> NameSpace
    occNameSpace (OccName -> NameSpace) -> OccName -> NameSpace
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrElt -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName GlobalRdrElt
    old_gre

    -- | Whether a 'GlobalRdrElt' is definitely shadowed, definitely not shadowed,
    -- or conditionally shadowed based on more information beyond the 'NameSpace'.
    data IsShadowed
      -- | The GRE is not shadowed.
      = IsNotShadowed
      -- | The GRE is shadowed.
      | IsShadowed
      -- | The GRE is shadowed iff it is a record field GRE
      -- which defines a field selector (i.e. FieldSelectors is enabled in its
      -- defining module).
      | IsShadowedIfFieldSelector

    -- | Internal function: is a 'GlobalRdrElt' with the 'NameSpace' with given
    -- 'Unique' shadowed by the specified 'ShadowedGREs'?
    namespace_is_shadowed :: Unique -> ShadowedGREs -> IsShadowed
    namespace_is_shadowed :: Unique -> ShadowedGREs -> IsShadowed
    namespace_is_shadowed Unique
    old_ns (ShadowedGREs UniqSet NameSpace
    shadowed_nonflds ShadowedFieldGREs
    shadowed_flds)
      | Unique -> Bool
    isFldNSUnique Unique
    old_ns
      = case ShadowedFieldGREs
    shadowed_flds of
          ShadowedFieldGREs
    ShadowAllFieldGREs -> IsShadowed
    IsShadowed
          ShadowFieldSelectorsAnd UniqSet NameSpace
    shadowed
            | Unique
    old_ns Unique -> UniqSet NameSpace -> Bool
    forall a. Unique -> UniqSet a -> Bool
    `elemUniqSet_Directly` UniqSet NameSpace
    shadowed
            -> IsShadowed
    IsShadowed
            | Bool
    otherwise
            -> IsShadowed
    IsShadowedIfFieldSelector
          ShadowFieldNameSpaces UniqSet NameSpace
    shadowed
            | Unique
    old_ns Unique -> UniqSet NameSpace -> Bool
    forall a. Unique -> UniqSet a -> Bool
    `elemUniqSet_Directly` UniqSet NameSpace
    shadowed
            -> IsShadowed
    IsShadowed
            | Bool
    otherwise
            -> IsShadowed
    IsNotShadowed
      | Unique
    old_ns Unique -> UniqSet NameSpace -> Bool
    forall a. Unique -> UniqSet a -> Bool
    `elemUniqSet_Directly` UniqSet NameSpace
    shadowed_nonflds
      = IsShadowed
    IsShadowed
      | Bool
    otherwise
      = IsShadowed
    IsNotShadowed

    -- | What are all the 'GlobalRdrElt's that are shadowed by this new 'GlobalRdrElt'?
    greShadowedNameSpaces :: GlobalRdrElt -> ShadowedGREs
    greShadowedNameSpaces :: GlobalRdrElt -> ShadowedGREs
    greShadowedNameSpaces GlobalRdrElt
    gre = UniqSet NameSpace -> ShadowedFieldGREs -> ShadowedGREs
    ShadowedGREs UniqSet NameSpace
    shadowed_nonflds ShadowedFieldGREs
    shadowed_flds
      where
        ns :: NameSpace
    ns = OccName -> NameSpace
    occNameSpace (OccName -> NameSpace) -> OccName -> NameSpace
    forall a b. (a -> b) -> a -> b
    $ GlobalRdrElt -> OccName
    forall info. GlobalRdrEltX info -> OccName
    greOccName GlobalRdrElt
    gre
        !shadowed_nonflds :: UniqSet NameSpace
    shadowed_nonflds
          | NameSpace -> Bool
    isFieldNameSpace NameSpace
    ns
          -- A new record field shadows variables if it defines a field selector.
          = if GlobalRdrElt -> Bool
    isFieldSelectorGRE GlobalRdrElt
    gre
            then NameSpace -> UniqSet NameSpace
    forall a. Uniquable a => a -> UniqSet a
    unitUniqSet NameSpace
    varName
            else UniqSet NameSpace
    forall a. UniqSet a
    emptyUniqSet
          | Bool
    otherwise
          = NameSpace -> UniqSet NameSpace
    forall a. Uniquable a => a -> UniqSet a
    unitUniqSet NameSpace
    ns
        !shadowed_flds :: ShadowedFieldGREs
    shadowed_flds
          | NameSpace
    ns NameSpace -> NameSpace -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace
    varName
          -- A new variable shadows record fields with field selectors.
          = UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldSelectorsAnd UniqSet NameSpace
    forall a. UniqSet a
    emptyUniqSet
          | NameSpace -> Bool
    isFieldNameSpace NameSpace
    ns
          -- A new record field shadows record fields unless it is a duplicate record field.
          = if GlobalRdrElt -> Bool
    isDuplicateRecFldGRE GlobalRdrElt
    gre
            then UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldNameSpaces (NameSpace -> UniqSet NameSpace
    forall a. Uniquable a => a -> UniqSet a
    unitUniqSet NameSpace
    ns)
            -- NB: we must still shadow fields with the same constructor name.
            else ShadowedFieldGREs
    ShadowAllFieldGREs
          | Bool
    otherwise
          = UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldNameSpaces UniqSet NameSpace
    forall a. UniqSet a
    emptyUniqSet

    -- | A description of which 'GlobalRdrElt's are shadowed.
    data ShadowedGREs
      = ShadowedGREs
        { ShadowedGREs -> UniqSet NameSpace
    shadowedNonFieldNameSpaces :: !(UniqSet NameSpace)
          -- ^ These specific non-field 'NameSpace's are shadowed.
        , ShadowedGREs -> ShadowedFieldGREs
    shadowedFieldGREs :: !ShadowedFieldGREs
          -- ^ These field 'GlobalRdrElt's are shadowed.
        }

    -- | A description of which record field 'GlobalRdrElt's are shadowed.
    data ShadowedFieldGREs
      -- | All field 'GlobalRdrElt's are shadowed.
      = ShadowAllFieldGREs
      -- | Record field GREs defining field selectors, as well as those
      -- with the explicitly specified field 'NameSpace's, are shadowed.
      | ShadowFieldSelectorsAnd { ShadowedFieldGREs -> UniqSet NameSpace
    shadowedFieldNameSpaces :: !(UniqSet NameSpace) }
      -- | These specific field 'NameSpace's are shadowed.
      | ShadowFieldNameSpaces { shadowedFieldNameSpaces :: !(UniqSet NameSpace) }

    instance Monoid ShadowedFieldGREs where
      mempty :: ShadowedFieldGREs
    mempty = ShadowFieldNameSpaces { shadowedFieldNameSpaces :: UniqSet NameSpace
    shadowedFieldNameSpaces = UniqSet NameSpace
    forall a. UniqSet a
    emptyUniqSet }

    instance Semigroup ShadowedFieldGREs where
      ShadowedFieldGREs
    ShadowAllFieldGREs <> :: ShadowedFieldGREs -> ShadowedFieldGREs -> ShadowedFieldGREs
    <> ShadowedFieldGREs
    _ = ShadowedFieldGREs
    ShadowAllFieldGREs
      ShadowedFieldGREs
    _ <> ShadowedFieldGREs
    ShadowAllFieldGREs = ShadowedFieldGREs
    ShadowAllFieldGREs
      ShadowFieldSelectorsAnd UniqSet NameSpace
    ns1 <> ShadowFieldSelectorsAnd UniqSet NameSpace
    ns2 =
        UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldSelectorsAnd (UniqSet NameSpace
    ns1 UniqSet NameSpace -> UniqSet NameSpace -> UniqSet NameSpace
    forall a. Semigroup a => a -> a -> a
    S.<> UniqSet NameSpace
    ns2)
      ShadowFieldSelectorsAnd UniqSet NameSpace
    ns1 <> ShadowFieldNameSpaces UniqSet NameSpace
    ns2 =
        UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldSelectorsAnd (UniqSet NameSpace
    ns1 UniqSet NameSpace -> UniqSet NameSpace -> UniqSet NameSpace
    forall a. Semigroup a => a -> a -> a
    S.<> UniqSet NameSpace
    ns2)
      ShadowFieldNameSpaces UniqSet NameSpace
    ns1 <> ShadowFieldSelectorsAnd UniqSet NameSpace
    ns2 =
        UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldSelectorsAnd (UniqSet NameSpace
    ns1 UniqSet NameSpace -> UniqSet NameSpace -> UniqSet NameSpace
    forall a. Semigroup a => a -> a -> a
    S.<> UniqSet NameSpace
    ns2)
      ShadowFieldNameSpaces UniqSet NameSpace
    ns1 <> ShadowFieldNameSpaces UniqSet NameSpace
    ns2 =
        UniqSet NameSpace -> ShadowedFieldGREs
    ShadowFieldNameSpaces (UniqSet NameSpace
    ns1 UniqSet NameSpace -> UniqSet NameSpace -> UniqSet NameSpace
    forall a. Semigroup a => a -> a -> a
    S.<> UniqSet NameSpace
    ns2)

    instance Monoid ShadowedGREs where
      mempty :: ShadowedGREs
    mempty =
        ShadowedGREs
          { shadowedNonFieldNameSpaces :: UniqSet NameSpace
    shadowedNonFieldNameSpaces = UniqSet NameSpace
    forall a. UniqSet a
    emptyUniqSet
          , shadowedFieldGREs :: ShadowedFieldGREs
    shadowedFieldGREs = ShadowedFieldGREs
    forall a. Monoid a => a
    mempty }

    instance Semigroup ShadowedGREs where
      ShadowedGREs UniqSet NameSpace
    nonflds1 ShadowedFieldGREs
    flds1 <> :: ShadowedGREs -> ShadowedGREs -> ShadowedGREs
    <> ShadowedGREs UniqSet NameSpace
    nonflds2 ShadowedFieldGREs
    flds2 =
        UniqSet NameSpace -> ShadowedFieldGREs -> ShadowedGREs
    ShadowedGREs (UniqSet NameSpace
    nonflds1 UniqSet NameSpace -> UniqSet NameSpace -> UniqSet NameSpace
    forall a. Semigroup a => a -> a -> a
    S.<> UniqSet NameSpace
    nonflds2) (ShadowedFieldGREs
    flds1 ShadowedFieldGREs -> ShadowedFieldGREs -> ShadowedFieldGREs
    forall a. Semigroup a => a -> a -> a
    S.<> ShadowedFieldGREs
    flds2)

    {-
    ************************************************************************
    *                                                                      *
                            ImportSpec
    *                                                                      *
    ************************************************************************
    -}

    -- | Import Specification
    --
    -- The 'ImportSpec' of something says how it came to be imported
    -- It's quite elaborate so that we can give accurate unused-name warnings.
    data ImportSpec = ImpSpec { ImportSpec -> ImpDeclSpec
    is_decl :: !ImpDeclSpec,
                                ImportSpec -> ImpItemSpec
    is_item :: !ImpItemSpec }
                    deriving( ImportSpec -> ImportSpec -> Bool
    (ImportSpec -> ImportSpec -> Bool)
    -> (ImportSpec -> ImportSpec -> Bool) -> Eq ImportSpec
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: ImportSpec -> ImportSpec -> Bool
    == :: ImportSpec -> ImportSpec -> Bool
    $c/= :: ImportSpec -> ImportSpec -> Bool
    /= :: ImportSpec -> ImportSpec -> Bool
    Eq, Typeable ImportSpec
    Typeable ImportSpec =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> ImportSpec -> c ImportSpec)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c ImportSpec)
    -> (ImportSpec -> Constr)
    -> (ImportSpec -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c ImportSpec))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e))
        -> Maybe (c ImportSpec))
    -> ((forall b. Data b => b -> b) -> ImportSpec -> ImportSpec)
    -> (forall r r'.
        (r -> r' -> r)
        -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r)
    -> (forall r r'.
        (r' -> r -> r)
        -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r)
    -> (forall u. (forall d. Data d => d -> u) -> ImportSpec -> [u])
    -> (forall u.
        Int -> (forall d. Data d => d -> u) -> ImportSpec -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec)
    -> Data ImportSpec
    ImportSpec -> Constr
    ImportSpec -> DataType
    (forall b. Data b => b -> b) -> ImportSpec -> ImportSpec
    forall a.
    Typeable a =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> a -> c a)
    -> (forall (c :: * -> *).
        (forall b r. Data b => c (b -> r) -> c r)
        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
    -> (a -> DataType)
    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall r r'.
        (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> ImportSpec -> u
    forall u. (forall d. Data d => d -> u) -> ImportSpec -> [u]
    forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c ImportSpec
    forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> ImportSpec -> c ImportSpec
    forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c ImportSpec)
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ImportSpec)
    $cgfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> ImportSpec -> c ImportSpec
    gfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> ImportSpec -> c ImportSpec
    $cgunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c ImportSpec
    gunfold :: forall (c :: * -> *).
    (forall b r. Data b => c (b -> r) -> c r)
    -> (forall r. r -> c r) -> Constr -> c ImportSpec
    $ctoConstr :: ImportSpec -> Constr
    toConstr :: ImportSpec -> Constr
    $cdataTypeOf :: ImportSpec -> DataType
    dataTypeOf :: ImportSpec -> DataType
    $cdataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c ImportSpec)
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c ImportSpec)
    $cdataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ImportSpec)
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ImportSpec)
    $cgmapT :: (forall b. Data b => b -> b) -> ImportSpec -> ImportSpec
    gmapT :: (forall b. Data b => b -> b) -> ImportSpec -> ImportSpec
    $cgmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    gmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    $cgmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    gmapQr :: forall r r'.
    (r' -> r -> r)
    -> r -> (forall d. Data d => d -> r') -> ImportSpec -> r
    $cgmapQ :: forall u. (forall d. Data d => d -> u) -> ImportSpec -> [u]
    gmapQ :: forall u. (forall d. Data d => d -> u) -> ImportSpec -> [u]
    $cgmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> ImportSpec -> u
    gmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> ImportSpec -> u
    $cgmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    gmapM :: forall (m :: * -> *).
    Monad m =>
    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    $cgmapMp :: forall (m :: * -> *).
    MonadPlus m =>
    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    gmapMp :: forall (m :: * -> *).
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    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    $cgmapMo :: forall (m :: * -> *).
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    (forall d. Data d => d -> m d) -> ImportSpec -> m ImportSpec
    gmapMo :: forall (m :: * -> *).
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    Data )

    instance NFData ImportSpec where
      rnf :: ImportSpec -> ()
    rnf = ImportSpec -> ()
    forall a. a -> ()
    rwhnf -- All fields are strict, so we don't need to do anything

    -- | Import Declaration Specification
    --
    -- Describes a particular import declaration and is
    -- shared among all the 'Provenance's for that decl
    data ImpDeclSpec
      = ImpDeclSpec {
            ImpDeclSpec -> Module
    is_mod      :: !Module,     -- ^ Module imported, e.g. @import Muggle@
                                       -- Note the @Muggle@ may well not be
                                       -- the defining module for this thing!

                                       -- TODO: either should be Module, or there
                                       -- should be a Maybe UnitId here too.
            ImpDeclSpec -> ModuleName
    is_as       :: !ModuleName, -- ^ Import alias, e.g. from @as M@ (or @Muggle@ if there is no @as@ clause)
            ImpDeclSpec -> Bool
    is_qual     :: !Bool,       -- ^ Was this import qualified?
            ImpDeclSpec -> SrcSpan
    is_dloc     :: !SrcSpan     -- ^ The location of the entire import declaration
        } deriving (ImpDeclSpec -> ImpDeclSpec -> Bool
    (ImpDeclSpec -> ImpDeclSpec -> Bool)
    -> (ImpDeclSpec -> ImpDeclSpec -> Bool) -> Eq ImpDeclSpec
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: ImpDeclSpec -> ImpDeclSpec -> Bool
    == :: ImpDeclSpec -> ImpDeclSpec -> Bool
    $c/= :: ImpDeclSpec -> ImpDeclSpec -> Bool
    /= :: ImpDeclSpec -> ImpDeclSpec -> Bool
    Eq, Typeable ImpDeclSpec
    Typeable ImpDeclSpec =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> ImpDeclSpec -> c ImpDeclSpec)
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        Typeable t =>
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    -> (forall (t :: * -> * -> *) (c :: * -> *).
        Typeable t =>
        (forall d e. (Data d, Data e) => c (t d e))
        -> Maybe (c ImpDeclSpec))
    -> ((forall b. Data b => b -> b) -> ImpDeclSpec -> ImpDeclSpec)
    -> (forall r r'.
        (r -> r' -> r)
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        (r' -> r -> r)
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    -> (forall u. (forall d. Data d => d -> u) -> ImpDeclSpec -> [u])
    -> (forall u.
        Int -> (forall d. Data d => d -> u) -> ImpDeclSpec -> u)
    -> (forall (m :: * -> *).
        Monad m =>
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    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> ImpDeclSpec -> m ImpDeclSpec)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> ImpDeclSpec -> m ImpDeclSpec)
    -> Data ImpDeclSpec
    ImpDeclSpec -> Constr
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    (forall b. Data b => b -> b) -> ImpDeclSpec -> ImpDeclSpec
    forall a.
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    (forall (c :: * -> *).
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        -> (forall r. r -> c r) -> Constr -> c a)
    -> (a -> Constr)
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    -> (forall (t :: * -> * -> *) (c :: * -> *).
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        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
    -> (forall r r'.
        (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> a -> r)
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    -> (forall u. (forall d. Data d => d -> u) -> a -> [u])
    -> (forall u. Int -> (forall d. Data d => d -> u) -> a -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
        MonadPlus m =>
        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> ImpDeclSpec -> u
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    -> (forall g. g -> c g) -> ImpDeclSpec -> c ImpDeclSpec
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    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c ImpDeclSpec)
    forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
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    -> Maybe (c ImpDeclSpec)
    $cgfoldl :: forall (c :: * -> *).
    (forall d b. Data d => c (d -> b) -> d -> c b)
    -> (forall g. g -> c g) -> ImpDeclSpec -> c ImpDeclSpec
    gfoldl :: forall (c :: * -> *).
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    -> (forall r. r -> c r) -> Constr -> c ImpDeclSpec
    $ctoConstr :: ImpDeclSpec -> Constr
    toConstr :: ImpDeclSpec -> Constr
    $cdataTypeOf :: ImpDeclSpec -> DataType
    dataTypeOf :: ImpDeclSpec -> DataType
    $cdataCast1 :: forall (t :: * -> *) (c :: * -> *).
    Typeable t =>
    (forall d. Data d => c (t d)) -> Maybe (c ImpDeclSpec)
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
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    (forall d. Data d => c (t d)) -> Maybe (c ImpDeclSpec)
    $cdataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
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    -> Maybe (c ImpDeclSpec)
    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
    Typeable t =>
    (forall d e. (Data d, Data e) => c (t d e))
    -> Maybe (c ImpDeclSpec)
    $cgmapT :: (forall b. Data b => b -> b) -> ImpDeclSpec -> ImpDeclSpec
    gmapT :: (forall b. Data b => b -> b) -> ImpDeclSpec -> ImpDeclSpec
    $cgmapQl :: forall r r'.
    (r -> r' -> r)
    -> r -> (forall d. Data d => d -> r') -> ImpDeclSpec -> r
    gmapQl :: forall r r'.
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    $cgmapQr :: forall r r'.
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    $cgmapQ :: forall u. (forall d. Data d => d -> u) -> ImpDeclSpec -> [u]
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    $cgmapQi :: forall u. Int -> (forall d. Data d => d -> u) -> ImpDeclSpec -> u
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    $cgmapM :: forall (m :: * -> *).
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    gmapM :: forall (m :: * -> *).
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    $cgmapMp :: forall (m :: * -> *).
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    Data)

    -- | Import Item Specification
    --
    -- Describes import info a particular Name
    data ImpItemSpec
      = ImpAll              -- ^ The import had no import list,
                            -- or had a hiding list

      | ImpSome {
            ImpItemSpec -> Bool
    is_explicit :: !Bool,
            ImpItemSpec -> SrcSpan
    is_iloc     :: !SrcSpan  -- Location of the import item
        }   -- ^ The import had an import list.
            -- The 'is_explicit' field is @True@ iff the thing was named
            -- /explicitly/ in the import specs rather
            -- than being imported as part of a "..." group. Consider:
            --
            -- > import C( T(..) )
            --
            -- Here the constructors of @T@ are not named explicitly;
            -- only @T@ is named explicitly.
      deriving (ImpItemSpec -> ImpItemSpec -> Bool
    (ImpItemSpec -> ImpItemSpec -> Bool)
    -> (ImpItemSpec -> ImpItemSpec -> Bool) -> Eq ImpItemSpec
    forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
    $c== :: ImpItemSpec -> ImpItemSpec -> Bool
    == :: ImpItemSpec -> ImpItemSpec -> Bool
    $c/= :: ImpItemSpec -> ImpItemSpec -> Bool
    /= :: ImpItemSpec -> ImpItemSpec -> Bool
    Eq, Typeable ImpItemSpec
    Typeable ImpItemSpec =>
    (forall (c :: * -> *).
     (forall d b. Data d => c (d -> b) -> d -> c b)
     -> (forall g. g -> c g) -> ImpItemSpec -> c ImpItemSpec)
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        -> (forall r. r -> c r) -> Constr -> c ImpItemSpec)
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    -> (forall (t :: * -> *) (c :: * -> *).
        Typeable t =>
        (forall d. Data d => c (t d)) -> Maybe (c ImpItemSpec))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
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        (forall d e. (Data d, Data e) => c (t d e))
        -> Maybe (c ImpItemSpec))
    -> ((forall b. Data b => b -> b) -> ImpItemSpec -> ImpItemSpec)
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        (r -> r' -> r)
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        Int -> (forall d. Data d => d -> u) -> ImpItemSpec -> u)
    -> (forall (m :: * -> *).
        Monad m =>
        (forall d. Data d => d -> m d) -> ImpItemSpec -> m ImpItemSpec)
    -> (forall (m :: * -> *).
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        (forall d. Data d => d -> m d) -> ImpItemSpec -> m ImpItemSpec)
    -> (forall (m :: * -> *).
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        (forall d. Data d => d -> m d) -> ImpItemSpec -> m ImpItemSpec)
    -> Data ImpItemSpec
    ImpItemSpec -> Constr
    ImpItemSpec -> DataType
    (forall b. Data b => b -> b) -> ImpItemSpec -> ImpItemSpec
    forall a.
    Typeable a =>
    (forall (c :: * -> *).
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     -> (forall g. g -> c g) -> a -> c a)
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    -> (a -> Constr)
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        (forall d. Data d => c (t d)) -> Maybe (c a))
    -> (forall (t :: * -> * -> *) (c :: * -> *).
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        (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c a))
    -> ((forall b. Data b => b -> b) -> a -> a)
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        (forall d. Data d => d -> m d) -> a -> m a)
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        (forall d. Data d => d -> m d) -> a -> m a)
    -> (forall (m :: * -> *).
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        (forall d. Data d => d -> m d) -> a -> m a)
    -> Data a
    forall u. Int -> (forall d. Data d => d -> u) -> ImpItemSpec -> u
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    $cgunfold :: forall (c :: * -> *).
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    -> (forall r. r -> c r) -> Constr -> c ImpItemSpec
    $ctoConstr :: ImpItemSpec -> Constr
    toConstr :: ImpItemSpec -> Constr
    $cdataTypeOf :: ImpItemSpec -> DataType
    dataTypeOf :: ImpItemSpec -> DataType
    $cdataCast1 :: forall (t :: * -> *) (c :: * -> *).
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    (forall d. Data d => c (t d)) -> Maybe (c ImpItemSpec)
    dataCast1 :: forall (t :: * -> *) (c :: * -> *).
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    (forall d. Data d => c (t d)) -> Maybe (c ImpItemSpec)
    $cdataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
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    dataCast2 :: forall (t :: * -> * -> *) (c :: * -> *).
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    (forall d e. (Data d, Data e) => c (t d e))
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    $cgmapT :: (forall b. Data b => b -> b) -> ImpItemSpec -> ImpItemSpec
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    gmapMo :: forall (m :: * -> *).
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    (forall d. Data d => d -> m d) -> ImpItemSpec -> m ImpItemSpec
    Data)

    bestImport :: NE.NonEmpty ImportSpec -> ImportSpec
    -- See Note [Choosing the best import declaration]
    bestImport :: NonEmpty ImportSpec -> ImportSpec
    bestImport NonEmpty ImportSpec
    iss = NonEmpty ImportSpec -> ImportSpec
    forall a. NonEmpty a -> a
    NE.head (NonEmpty ImportSpec -> ImportSpec)
    -> NonEmpty ImportSpec -> ImportSpec
    forall a b. (a -> b) -> a -> b
    $ (ImportSpec -> ImportSpec -> Ordering)
    -> NonEmpty ImportSpec -> NonEmpty ImportSpec
    forall a. (a -> a -> Ordering) -> NonEmpty a -> NonEmpty a
    NE.sortBy ImportSpec -> ImportSpec -> Ordering
    best NonEmpty ImportSpec
    iss
      where
        best :: ImportSpec -> ImportSpec -> Ordering
        -- Less means better
        -- Unqualified always wins over qualified; then
        -- import-all wins over import-some; then
        -- earlier declaration wins over later
        best :: ImportSpec -> ImportSpec -> Ordering
    best (ImpSpec { is_item :: ImportSpec -> ImpItemSpec
    is_item = ImpItemSpec
    item1, is_decl :: ImportSpec -> ImpDeclSpec
    is_decl = ImpDeclSpec
    d1 })
             (ImpSpec { is_item :: ImportSpec -> ImpItemSpec
    is_item = ImpItemSpec
    item2, is_decl :: ImportSpec -> ImpDeclSpec
    is_decl = ImpDeclSpec
    d2 })
          = (ImpDeclSpec -> Bool
    is_qual ImpDeclSpec
    d1 Bool -> Bool -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` ImpDeclSpec -> Bool
    is_qual ImpDeclSpec
    d2) Ordering -> Ordering -> Ordering
    forall a. Semigroup a => a -> a -> a
    S.<> ImpItemSpec -> ImpItemSpec -> Ordering
    best_item ImpItemSpec
    item1 ImpItemSpec
    item2 Ordering -> Ordering -> Ordering
    forall a. Semigroup a => a -> a -> a
    S.<>
            SrcSpan -> SrcSpan -> Ordering
    SrcLoc.leftmost_smallest (ImpDeclSpec -> SrcSpan
    is_dloc ImpDeclSpec
    d1) (ImpDeclSpec -> SrcSpan
    is_dloc ImpDeclSpec
    d2)

        best_item :: ImpItemSpec -> ImpItemSpec -> Ordering
        best_item :: ImpItemSpec -> ImpItemSpec -> Ordering
    best_item ImpItemSpec
    ImpAll ImpItemSpec
    ImpAll = Ordering
    EQ
        best_item ImpItemSpec
    ImpAll (ImpSome {}) = Ordering
    LT
        best_item (ImpSome {}) ImpItemSpec
    ImpAll = Ordering
    GT
        best_item (ImpSome { is_explicit :: ImpItemSpec -> Bool
    is_explicit = Bool
    e1 })
                  (ImpSome { is_explicit :: ImpItemSpec -> Bool
    is_explicit = Bool
    e2 }) = Bool
    e1 Bool -> Bool -> Ordering
    forall a. Ord a => a -> a -> Ordering
    `compare` Bool
    e2
         -- False < True, so if e1 is explicit and e2 is not, we get GT

    {- Note [Choosing the best import declaration]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    When reporting unused import declarations we use the following rules.
       (see [wiki:commentary/compiler/unused-imports])

    Say that an import-item is either
      * an entire import-all decl (eg import Foo), or
      * a particular item in an import list (eg import Foo( ..., x, ...)).
    The general idea is that for each /occurrence/ of an imported name, we will
    attribute that use to one import-item. Once we have processed all the
    occurrences, any import items with no uses attributed to them are unused,
    and are warned about. More precisely:

    1. For every RdrName in the program text, find its GlobalRdrElt.

    2. Then, from the [ImportSpec] (gre_imp) of that GRE, choose one
       the "chosen import-item", and mark it "used". This is done
       by 'bestImport'

    3. After processing all the RdrNames, bleat about any
       import-items that are unused.
       This is done in GHC.Rename.Names.warnUnusedImportDecls.

    The function 'bestImport' returns the dominant import among the
    ImportSpecs it is given, implementing Step 2.  We say import-item A
    dominates import-item B if we choose A over B. In general, we try to
    choose the import that is most likely to render other imports
    unnecessary.  Here is the dominance relationship we choose:

        a) import Foo dominates import qualified Foo.

        b) import Foo dominates import Foo(x).

        c) Otherwise choose the textually first one.

    Rationale for (a).  Consider
       import qualified M  -- Import #1
       import M( x )       -- Import #2
       foo = M.x + x

    The unqualified 'x' can only come from import #2.  The qualified 'M.x'
    could come from either, but bestImport picks import #2, because it is
    more likely to be useful in other imports, as indeed it is in this
    case (see #5211 for a concrete example).

    But the rules are not perfect; consider
       import qualified M  -- Import #1
       import M( x )       -- Import #2
       foo = M.x + M.y

    The M.x will use import #2, but M.y can only use import #1.
    -}

    unQualSpecOK :: ImportSpec -> Bool
    -- ^ Is in scope unqualified?
    unQualSpecOK :: ImportSpec -> Bool
    unQualSpecOK ImportSpec
    is = Bool -> Bool
    not (ImpDeclSpec -> Bool
    is_qual (ImportSpec -> ImpDeclSpec
    is_decl ImportSpec
    is))

    qualSpecOK :: ModuleName -> ImportSpec -> Bool
    -- ^ Is in scope qualified with the given module?
    qualSpecOK :: ModuleName -> ImportSpec -> Bool
    qualSpecOK ModuleName
    mod ImportSpec
    is = ModuleName
    mod ModuleName -> ModuleName -> Bool
    forall a. Eq a => a -> a -> Bool
    == ImpDeclSpec -> ModuleName
    is_as (ImportSpec -> ImpDeclSpec
    is_decl ImportSpec
    is)

    importSpecLoc :: ImportSpec -> SrcSpan
    importSpecLoc :: ImportSpec -> SrcSpan
    importSpecLoc (ImpSpec ImpDeclSpec
    decl ImpItemSpec
    ImpAll) = ImpDeclSpec -> SrcSpan
    is_dloc ImpDeclSpec
    decl
    importSpecLoc (ImpSpec ImpDeclSpec
    _    ImpItemSpec
    item)   = ImpItemSpec -> SrcSpan
    is_iloc ImpItemSpec
    item

    importSpecModule :: ImportSpec -> ModuleName
    importSpecModule :: ImportSpec -> ModuleName
    importSpecModule = Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName (Module -> ModuleName)
    -> (ImportSpec -> Module) -> ImportSpec -> ModuleName
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . ImpDeclSpec -> Module
    is_mod (ImpDeclSpec -> Module)
    -> (ImportSpec -> ImpDeclSpec) -> ImportSpec -> Module
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . ImportSpec -> ImpDeclSpec
    is_decl

    isExplicitItem :: ImpItemSpec -> Bool
    isExplicitItem :: ImpItemSpec -> Bool
    isExplicitItem ImpItemSpec
    ImpAll                        = Bool
    False
    isExplicitItem (ImpSome {is_explicit :: ImpItemSpec -> Bool
    is_explicit = Bool
    exp}) = Bool
    exp

    pprNameProvenance :: GlobalRdrEltX info -> SDoc
    -- ^ Print out one place where the name was define/imported
    -- (With -dppr-debug, print them all)
    pprNameProvenance :: forall info. GlobalRdrEltX info -> SDoc
    pprNameProvenance (GRE { gre_name :: forall info. GlobalRdrEltX info -> Name
    gre_name = Name
    name, gre_lcl :: forall info. GlobalRdrEltX info -> Bool
    gre_lcl = Bool
    lcl, gre_imp :: forall info. GlobalRdrEltX info -> Bag ImportSpec
    gre_imp = Bag ImportSpec
    iss })
      = SDoc -> SDoc -> SDoc
    forall doc. IsOutput doc => doc -> doc -> doc
    ifPprDebug ([SDoc] -> SDoc
    forall doc. IsDoc doc => [doc] -> doc
    vcat [SDoc]
    pp_provs)
                   ([SDoc] -> SDoc
    forall a. HasCallStack => [a] -> a
    head [SDoc]
    pp_provs)
      where
        pp_provs :: [SDoc]
    pp_provs = [SDoc]
    pp_lcl [SDoc] -> [SDoc] -> [SDoc]
    forall a. [a] -> [a] -> [a]
    ++ (ImportSpec -> SDoc) -> [ImportSpec] -> [SDoc]
    forall a b. (a -> b) -> [a] -> [b]
    map ImportSpec -> SDoc
    pp_is (Bag ImportSpec -> [ImportSpec]
    forall a. Bag a -> [a]
    bagToList Bag ImportSpec
    iss)
        pp_lcl :: [SDoc]
    pp_lcl = if Bool
    lcl then [String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "defined at" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SrcLoc -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (Name -> SrcLoc
    nameSrcLoc Name
    name)]
                        else []
        pp_is :: ImportSpec -> SDoc
    pp_is ImportSpec
    is = [SDoc] -> SDoc
    forall doc. IsLine doc => [doc] -> doc
    sep [ImportSpec -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr ImportSpec
    is, ImportSpec -> Name -> SDoc
    ppr_defn_site ImportSpec
    is Name
    name]

    -- If we know the exact definition point (which we may do with GHCi)
    -- then show that too.  But not if it's just "imported from X".
    ppr_defn_site :: ImportSpec -> Name -> SDoc
    ppr_defn_site :: ImportSpec -> Name -> SDoc
    ppr_defn_site ImportSpec
    imp_spec Name
    name
      | Bool
    same_module Bool -> Bool -> Bool
    && Bool -> Bool
    not (SrcSpan -> Bool
    isGoodSrcSpan SrcSpan
    loc)
      = SDoc
    forall doc. IsOutput doc => doc
    empty              -- Nothing interesting to say
      | Bool
    otherwise
      = SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc
    parens (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
    "and originally defined" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc
    pp_mod)
                    Int
    2 (SrcSpan -> SDoc
    pprLoc SrcSpan
    loc)
      where
        loc :: SrcSpan
    loc = Name -> SrcSpan
    nameSrcSpan Name
    name
        defining_mod :: Module
    defining_mod = Bool -> SDoc -> Module -> Module
    forall a. HasCallStack => Bool -> SDoc -> a -> a
    assertPpr (Name -> Bool
    isExternalName Name
    name) (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name) (Module -> Module) -> Module -> Module
    forall a b. (a -> b) -> a -> b
    $ HasDebugCallStack => Name -> Module
    Name -> Module
    nameModule Name
    name
        same_module :: Bool
    same_module = ImportSpec -> ModuleName
    importSpecModule ImportSpec
    imp_spec ModuleName -> ModuleName -> Bool
    forall a. Eq a => a -> a -> Bool
    == Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName Module
    defining_mod
        pp_mod :: SDoc
    pp_mod | Bool
    same_module = SDoc
    forall doc. IsOutput doc => doc
    empty
               | Bool
    otherwise   = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "in" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc -> SDoc
    quotes (Module -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Module
    defining_mod)

    instance Outputable ImportSpec where
       ppr :: ImportSpec -> SDoc
    ppr ImportSpec
    imp_spec
         = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "imported" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc
    qual
            SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "from" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SDoc -> SDoc
    quotes (ModuleName -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (ImportSpec -> ModuleName
    importSpecModule ImportSpec
    imp_spec))
            SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> SrcSpan -> SDoc
    pprLoc (ImportSpec -> SrcSpan
    importSpecLoc ImportSpec
    imp_spec)
         where
           qual :: SDoc
    qual | ImpDeclSpec -> Bool
    is_qual (ImportSpec -> ImpDeclSpec
    is_decl ImportSpec
    imp_spec) = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "qualified"
                | Bool
    otherwise                  = SDoc
    forall doc. IsOutput doc => doc
    empty

    pprLoc :: SrcSpan -> SDoc
    pprLoc :: SrcSpan -> SDoc
    pprLoc (RealSrcSpan RealSrcSpan
    s Maybe BufSpan
    _)  = String -> SDoc
    forall doc. IsLine doc => String -> doc
    text String
    "at" SDoc -> SDoc -> SDoc
    forall doc. IsLine doc => doc -> doc -> doc
    <+> RealSrcSpan -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RealSrcSpan
    s
    pprLoc (UnhelpfulSpan {}) = SDoc
    forall doc. IsOutput doc => doc
    empty

    -- | Indicate if the given name is the "@" operator
    opIsAt :: RdrName -> Bool
    opIsAt :: RdrName -> Bool
    opIsAt RdrName
    e = RdrName
    e RdrName -> RdrName -> Bool
    forall a. Eq a => a -> a -> Bool
    == NameSpace -> FastString -> RdrName
    mkUnqual NameSpace
    varName (String -> FastString
    fsLit String
    "@")