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

    {-# LANGUAGE CPP #-}
    {-# LANGUAGE DeriveDataTypeable, DeriveFunctor, DeriveFoldable,
                 DeriveTraversable #-}
    {-# LANGUAGE StandaloneDeriving #-}
    {-# LANGUAGE FlexibleContexts #-}
    {-# LANGUAGE UndecidableInstances #-} -- Note [Pass sensitive types]
                                          -- in module PlaceHolder
    {-# LANGUAGE ConstraintKinds #-}
    {-# LANGUAGE FlexibleInstances #-}
    {-# OPTIONS_GHC -fno-warn-orphans #-}

    -- | Abstract syntax of global declarations.
    --
    -- Definitions for: @SynDecl@ and @ConDecl@, @ClassDecl@,
    -- @InstDecl@, @DefaultDecl@ and @ForeignDecl@.
    module HsDecls (
      -- * Toplevel declarations
      HsDecl(..), LHsDecl, HsDataDefn(..),
      -- ** Class or type declarations
      TyClDecl(..), LTyClDecl,
      TyClGroup(..), tyClGroupConcat, mkTyClGroup,
      isClassDecl, isDataDecl, isSynDecl, tcdName,
      isFamilyDecl, isTypeFamilyDecl, isDataFamilyDecl,
      isOpenTypeFamilyInfo, isClosedTypeFamilyInfo,
      tyFamInstDeclName, tyFamInstDeclLName,
      countTyClDecls, pprTyClDeclFlavour,
      tyClDeclLName, tyClDeclTyVars,
      hsDeclHasCusk, famDeclHasCusk,
      FamilyDecl(..), LFamilyDecl,

      -- ** Instance declarations
      InstDecl(..), LInstDecl, NewOrData(..), FamilyInfo(..),
      TyFamInstDecl(..), LTyFamInstDecl, instDeclDataFamInsts,
      DataFamInstDecl(..), LDataFamInstDecl, pprDataFamInstFlavour,
      TyFamEqn(..), TyFamInstEqn, LTyFamInstEqn, TyFamDefltEqn, LTyFamDefltEqn,
      HsTyPats,
      LClsInstDecl, ClsInstDecl(..),

      -- ** Standalone deriving declarations
      DerivDecl(..), LDerivDecl,
      -- ** @RULE@ declarations
      LRuleDecls,RuleDecls(..),RuleDecl(..), LRuleDecl, RuleBndr(..),LRuleBndr,
      collectRuleBndrSigTys,
      flattenRuleDecls,
      -- ** @VECTORISE@ declarations
      VectDecl(..), LVectDecl,
      lvectDeclName, lvectInstDecl,
      -- ** @default@ declarations
      DefaultDecl(..), LDefaultDecl,
      -- ** Template haskell declaration splice
      SpliceExplicitFlag(..),
      SpliceDecl(..), LSpliceDecl,
      -- ** Foreign function interface declarations
      ForeignDecl(..), LForeignDecl, ForeignImport(..), ForeignExport(..),
      noForeignImportCoercionYet, noForeignExportCoercionYet,
      CImportSpec(..),
      -- ** Data-constructor declarations
      ConDecl(..), LConDecl, ResType(..),
      HsConDeclDetails, hsConDeclArgTys,
      -- ** Document comments
      DocDecl(..), LDocDecl, docDeclDoc,
      -- ** Deprecations
      WarnDecl(..),  LWarnDecl,
      WarnDecls(..), LWarnDecls,
      -- ** Annotations
      AnnDecl(..), LAnnDecl,
      AnnProvenance(..), annProvenanceName_maybe,
      -- ** Role annotations
      RoleAnnotDecl(..), LRoleAnnotDecl, roleAnnotDeclName,

      -- * Grouping
      HsGroup(..),  emptyRdrGroup, emptyRnGroup, appendGroups

        ) where

    -- friends:
    import {-# SOURCE #-}   HsExpr( LHsExpr, HsExpr, HsSplice, pprExpr, pprUntypedSplice )
            -- Because Expr imports Decls via HsBracket

    import HsBinds
    import HsPat
    import HsTypes
    import HsDoc
    import TyCon
    import Name
    import BasicTypes
    import Coercion
    import ForeignCall
    import PlaceHolder ( PostTc,PostRn,PlaceHolder(..),DataId )
    import NameSet

    -- others:
    import InstEnv
    import Class
    import Outputable
    import Util
    import SrcLoc
    import FastString

    import Bag
    import Data.Data        hiding (TyCon,Fixity)
    #if __GLASGOW_HASKELL__ < 709
    import Data.Foldable ( Foldable )
    import Data.Traversable ( Traversable )
    #endif
    import Data.Maybe

    {-
    ************************************************************************
    *                                                                      *
    \subsection[HsDecl]{Declarations}
    *                                                                      *
    ************************************************************************
    -}

    type LHsDecl id = Located (HsDecl id)
            -- ^ When in a list this may have
            --
            --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi'
            --

    -- For details on above see note [Api annotations] in ApiAnnotation

    -- | A Haskell Declaration
    data HsDecl id
      = TyClD       (TyClDecl id)     -- ^ A type or class declaration.
      | InstD       (InstDecl  id)    -- ^ An instance declaration.
      | DerivD      (DerivDecl id)
      | ValD        (HsBind id)
      | SigD        (Sig id)
      | DefD        (DefaultDecl id)
      | ForD        (ForeignDecl id)
      | WarningD    (WarnDecls id)
      | AnnD        (AnnDecl id)
      | RuleD       (RuleDecls id)
      | VectD       (VectDecl id)
      | SpliceD     (SpliceDecl id)
      | DocD        (DocDecl)
      | QuasiQuoteD (HsQuasiQuote id)
      | RoleAnnotD  (RoleAnnotDecl id)
      deriving (Typeable)
    deriving instance (DataId id) => Data (HsDecl id)

    -- NB: all top-level fixity decls are contained EITHER
    -- EITHER SigDs
    -- OR     in the ClassDecls in TyClDs
    --
    -- The former covers
    --      a) data constructors
    --      b) class methods (but they can be also done in the
    --              signatures of class decls)
    --      c) imported functions (that have an IfacSig)
    --      d) top level decls
    --
    -- The latter is for class methods only

    -- | A 'HsDecl' is categorised into a 'HsGroup' before being
    -- fed to the renamer.
    data HsGroup id
      = HsGroup {
            hs_valds  :: HsValBinds id,
            hs_splcds :: [LSpliceDecl id],

            hs_tyclds :: [TyClGroup id],
                    -- A list of mutually-recursive groups
                    -- No family-instances here; they are in hs_instds
                    -- Parser generates a singleton list;
                    -- renamer does dependency analysis

            hs_instds  :: [LInstDecl id],
                    -- Both class and family instance declarations in here

            hs_derivds :: [LDerivDecl id],

            hs_fixds  :: [LFixitySig id],
                    -- Snaffled out of both top-level fixity signatures,
                    -- and those in class declarations

            hs_defds  :: [LDefaultDecl id],
            hs_fords  :: [LForeignDecl id],
            hs_warnds :: [LWarnDecls id],
            hs_annds  :: [LAnnDecl id],
            hs_ruleds :: [LRuleDecls id],
            hs_vects  :: [LVectDecl id],

            hs_docs   :: [LDocDecl]
      } deriving (Typeable)
    deriving instance (DataId id) => Data (HsGroup id)

    emptyGroup, emptyRdrGroup, emptyRnGroup :: HsGroup a
    emptyRdrGroup = emptyGroup { hs_valds = emptyValBindsIn }
    emptyRnGroup  = emptyGroup { hs_valds = emptyValBindsOut }

    emptyGroup = HsGroup { hs_tyclds = [], hs_instds = [],
                           hs_derivds = [],
                           hs_fixds = [], hs_defds = [], hs_annds = [],
                           hs_fords = [], hs_warnds = [], hs_ruleds = [], hs_vects = [],
                           hs_valds = error "emptyGroup hs_valds: Can't happen",
                           hs_splcds = [],
                           hs_docs = [] }

    appendGroups :: HsGroup a -> HsGroup a -> HsGroup a
    appendGroups
        HsGroup {
            hs_valds  = val_groups1,
            hs_splcds = spliceds1,
            hs_tyclds = tyclds1,
            hs_instds = instds1,
            hs_derivds = derivds1,
            hs_fixds  = fixds1,
            hs_defds  = defds1,
            hs_annds  = annds1,
            hs_fords  = fords1,
            hs_warnds = warnds1,
            hs_ruleds = rulds1,
            hs_vects = vects1,
      hs_docs   = docs1 }
        HsGroup {
            hs_valds  = val_groups2,
            hs_splcds = spliceds2,
            hs_tyclds = tyclds2,
            hs_instds = instds2,
            hs_derivds = derivds2,
            hs_fixds  = fixds2,
            hs_defds  = defds2,
            hs_annds  = annds2,
            hs_fords  = fords2,
            hs_warnds = warnds2,
            hs_ruleds = rulds2,
            hs_vects  = vects2,
            hs_docs   = docs2 }
      =
        HsGroup {
            hs_valds  = val_groups1 `plusHsValBinds` val_groups2,
            hs_splcds = spliceds1 ++ spliceds2,
            hs_tyclds = tyclds1 ++ tyclds2,
            hs_instds = instds1 ++ instds2,
            hs_derivds = derivds1 ++ derivds2,
            hs_fixds  = fixds1 ++ fixds2,
            hs_annds  = annds1 ++ annds2,
            hs_defds  = defds1 ++ defds2,
            hs_fords  = fords1 ++ fords2,
            hs_warnds = warnds1 ++ warnds2,
            hs_ruleds = rulds1 ++ rulds2,
            hs_vects  = vects1 ++ vects2,
            hs_docs   = docs1  ++ docs2 }

    instance OutputableBndr name => Outputable (HsDecl name) where
        ppr (TyClD dcl)             = ppr dcl
        ppr (ValD binds)            = ppr binds
        ppr (DefD def)              = ppr def
        ppr (InstD inst)            = ppr inst
        ppr (DerivD deriv)          = ppr deriv
        ppr (ForD fd)               = ppr fd
        ppr (SigD sd)               = ppr sd
        ppr (RuleD rd)              = ppr rd
        ppr (VectD vect)            = ppr vect
        ppr (WarningD wd)           = ppr wd
        ppr (AnnD ad)               = ppr ad
        ppr (SpliceD dd)            = ppr dd
        ppr (DocD doc)              = ppr doc
        ppr (QuasiQuoteD qq)        = ppr qq
        ppr (RoleAnnotD ra)         = ppr ra

    instance OutputableBndr name => Outputable (HsGroup name) where
        ppr (HsGroup { hs_valds  = val_decls,
                       hs_tyclds = tycl_decls,
                       hs_instds = inst_decls,
                       hs_derivds = deriv_decls,
                       hs_fixds  = fix_decls,
                       hs_warnds = deprec_decls,
                       hs_annds  = ann_decls,
                       hs_fords  = foreign_decls,
                       hs_defds  = default_decls,
                       hs_ruleds = rule_decls,
                       hs_vects  = vect_decls })
            = vcat_mb empty
                [ppr_ds fix_decls, ppr_ds default_decls,
                 ppr_ds deprec_decls, ppr_ds ann_decls,
                 ppr_ds rule_decls,
                 ppr_ds vect_decls,
                 if isEmptyValBinds val_decls
                    then Nothing
                    else Just (ppr val_decls),
                 ppr_ds (tyClGroupConcat tycl_decls),
                 ppr_ds inst_decls,
                 ppr_ds deriv_decls,
                 ppr_ds foreign_decls]
            where
              ppr_ds :: Outputable a => [a] -> Maybe SDoc
              ppr_ds [] = Nothing
              ppr_ds ds = Just (vcat (map ppr ds))

              vcat_mb :: SDoc -> [Maybe SDoc] -> SDoc
              -- Concatenate vertically with white-space between non-blanks
              vcat_mb _    []             = empty
              vcat_mb gap (Nothing : ds) = vcat_mb gap ds
              vcat_mb gap (Just d  : ds) = gap $$ d $$ vcat_mb blankLine ds

    data SpliceExplicitFlag = ExplicitSplice | -- <=> $(f x y)
                              ImplicitSplice   -- <=> f x y,  i.e. a naked top level expression
        deriving (Data, Typeable)

    type LSpliceDecl name = Located (SpliceDecl name)
    data SpliceDecl id
      = SpliceDecl                  -- Top level splice
            (Located (HsSplice id))
            SpliceExplicitFlag
        deriving (Typeable)
    deriving instance (DataId id) => Data (SpliceDecl id)

    instance OutputableBndr name => Outputable (SpliceDecl name) where
       ppr (SpliceDecl (L _ e) _) = pprUntypedSplice e

    {-
    ************************************************************************
    *                                                                      *
    \subsection[SynDecl]{@data@, @newtype@ or @type@ (synonym) type declaration}
    *                                                                      *
    ************************************************************************

                    --------------------------------
                            THE NAMING STORY
                    --------------------------------

    Here is the story about the implicit names that go with type, class,
    and instance decls.  It's a bit tricky, so pay attention!

    "Implicit" (or "system") binders
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      Each data type decl defines
            a worker name for each constructor
            to-T and from-T convertors
      Each class decl defines
            a tycon for the class
            a data constructor for that tycon
            the worker for that constructor
            a selector for each superclass

    All have occurrence names that are derived uniquely from their parent
    declaration.

    None of these get separate definitions in an interface file; they are
    fully defined by the data or class decl.  But they may *occur* in
    interface files, of course.  Any such occurrence must haul in the
    relevant type or class decl.

    Plan of attack:
     - Ensure they "point to" the parent data/class decl
       when loading that decl from an interface file
       (See RnHiFiles.getSysBinders)

     - When typechecking the decl, we build the implicit TyCons and Ids.
       When doing so we look them up in the name cache (RnEnv.lookupSysName),
       to ensure correct module and provenance is set

    These are the two places that we have to conjure up the magic derived
    names.  (The actual magic is in OccName.mkWorkerOcc, etc.)

    Default methods
    ~~~~~~~~~~~~~~~
     - Occurrence name is derived uniquely from the method name
       E.g. $dmmax

     - If there is a default method name at all, it's recorded in
       the ClassOpSig (in HsBinds), in the DefMeth field.
       (DefMeth is defined in Class.lhs)

    Source-code class decls and interface-code class decls are treated subtly
    differently, which has given me a great deal of confusion over the years.
    Here's the deal.  (We distinguish the two cases because source-code decls
    have (Just binds) in the tcdMeths field, whereas interface decls have Nothing.

    In *source-code* class declarations:

     - When parsing, every ClassOpSig gets a DefMeth with a suitable RdrName
       This is done by RdrHsSyn.mkClassOpSigDM

     - The renamer renames it to a Name

     - During typechecking, we generate a binding for each $dm for
       which there's a programmer-supplied default method:
            class Foo a where
              op1 :: <type>
              op2 :: <type>
              op1 = ...
       We generate a binding for $dmop1 but not for $dmop2.
       The Class for Foo has a NoDefMeth for op2 and a DefMeth for op1.
       The Name for $dmop2 is simply discarded.

    In *interface-file* class declarations:
      - When parsing, we see if there's an explicit programmer-supplied default method
        because there's an '=' sign to indicate it:
            class Foo a where
              op1 = :: <type>       -- NB the '='
              op2   :: <type>
        We use this info to generate a DefMeth with a suitable RdrName for op1,
        and a NoDefMeth for op2
      - The interface file has a separate definition for $dmop1, with unfolding etc.
      - The renamer renames it to a Name.
      - The renamer treats $dmop1 as a free variable of the declaration, so that
        the binding for $dmop1 will be sucked in.  (See RnHsSyn.tyClDeclFVs)
        This doesn't happen for source code class decls, because they *bind* the default method.

    Dictionary functions
    ~~~~~~~~~~~~~~~~~~~~
    Each instance declaration gives rise to one dictionary function binding.

    The type checker makes up new source-code instance declarations
    (e.g. from 'deriving' or generic default methods --- see
    TcInstDcls.tcInstDecls1).  So we can't generate the names for
    dictionary functions in advance (we don't know how many we need).

    On the other hand for interface-file instance declarations, the decl
    specifies the name of the dictionary function, and it has a binding elsewhere
    in the interface file:
            instance {Eq Int} = dEqInt
            dEqInt :: {Eq Int} <pragma info>

    So again we treat source code and interface file code slightly differently.

    Source code:
      - Source code instance decls have a Nothing in the (Maybe name) field
        (see data InstDecl below)

      - The typechecker makes up a Local name for the dict fun for any source-code
        instance decl, whether it comes from a source-code instance decl, or whether
        the instance decl is derived from some other construct (e.g. 'deriving').

      - The occurrence name it chooses is derived from the instance decl (just for
        documentation really) --- e.g. dNumInt.  Two dict funs may share a common
        occurrence name, but will have different uniques.  E.g.
            instance Foo [Int]  where ...
            instance Foo [Bool] where ...
        These might both be dFooList

      - The CoreTidy phase externalises the name, and ensures the occurrence name is
        unique (this isn't special to dict funs).  So we'd get dFooList and dFooList1.

      - We can take this relaxed approach (changing the occurrence name later)
        because dict fun Ids are not captured in a TyCon or Class (unlike default
        methods, say).  Instead, they are kept separately in the InstEnv.  This
        makes it easy to adjust them after compiling a module.  (Once we've finished
        compiling that module, they don't change any more.)

    Interface file code:
      - The instance decl gives the dict fun name, so the InstDecl has a (Just name)
        in the (Maybe name) field.

      - RnHsSyn.instDeclFVs treats the dict fun name as free in the decl, so that we
        suck in the dfun binding
    -}

    type LTyClDecl name = Located (TyClDecl name)

    -- | A type or class declaration.
    data TyClDecl name
      = -- | @type/data family T :: *->*@
        --
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
        --             'ApiAnnotation.AnnData',
        --             'ApiAnnotation.AnnFamily','ApiAnnotation.AnnDcolon',
        --             'ApiAnnotation.AnnWhere',
        --             'ApiAnnotation.AnnOpen','ApiAnnotation.AnnDcolon',
        --             'ApiAnnotation.AnnClose'

        -- For details on above see note [Api annotations] in ApiAnnotation
        FamDecl { tcdFam :: FamilyDecl name }

      | -- | @type@ declaration
        --
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
        --             'ApiAnnotation.AnnEqual',

        -- For details on above see note [Api annotations] in ApiAnnotation
        SynDecl { tcdLName  :: Located name            -- ^ Type constructor
                , tcdTyVars :: LHsTyVarBndrs name      -- ^ Type variables; for an associated type
                                                      --   these include outer binders
                , tcdRhs    :: LHsType name            -- ^ RHS of type declaration
                , tcdFVs    :: PostRn name NameSet }

      | -- | @data@ declaration
        --
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnData',
        --              'ApiAnnotation.AnnFamily',
        --              'ApiAnnotation.AnnNewType',
        --              'ApiAnnotation.AnnNewType','ApiAnnotation.AnnDcolon'
        --              'ApiAnnotation.AnnWhere',

        -- For details on above see note [Api annotations] in ApiAnnotation
        DataDecl { tcdLName    :: Located name        -- ^ Type constructor
                 , tcdTyVars   :: LHsTyVarBndrs name  -- ^ Type variables; for an assoicated type
                                                      --   these include outer binders
                                                      -- Eg  class T a where
                                                      --       type F a :: *
                                                      --       type F a = a -> a
                                                      -- Here the type decl for 'f' includes 'a'
                                                      -- in its tcdTyVars
                 , tcdDataDefn :: HsDataDefn name
                 , tcdFVs      :: PostRn name NameSet }

      | ClassDecl { tcdCtxt    :: LHsContext name,          -- ^ Context...
                    tcdLName   :: Located name,             -- ^ Name of the class
                    tcdTyVars  :: LHsTyVarBndrs name,       -- ^ Class type variables
                    tcdFDs     :: [Located (FunDep (Located name))],
                                                            -- ^ Functional deps
                    tcdSigs    :: [LSig name],              -- ^ Methods' signatures
                    tcdMeths   :: LHsBinds name,            -- ^ Default methods
                    tcdATs     :: [LFamilyDecl name],       -- ^ Associated types;
                    tcdATDefs  :: [LTyFamDefltEqn name],    -- ^ Associated type defaults
                    tcdDocs    :: [LDocDecl],               -- ^ Haddock docs
                    tcdFVs     :: PostRn name NameSet
        }
            -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnClass',
            --           'ApiAnnotation.AnnWhere','ApiAnnotation.AnnOpen',
            --           'ApiAnnotation.AnnClose'
            --   - The tcdFDs will have 'ApiAnnotation.AnnVbar',
            --                          'ApiAnnotation.AnnComma'
            --                          'ApiAnnotation.AnnRarrow'

            -- For details on above see note [Api annotations] in ApiAnnotation

      deriving (Typeable)
    deriving instance (DataId id) => Data (TyClDecl id)

     -- This is used in TcTyClsDecls to represent
     -- strongly connected components of decls
     -- No familiy instances in here
     -- The role annotations must be grouped with their decls for the
     -- type-checker to infer roles correctly
    data TyClGroup name
      = TyClGroup { group_tyclds :: [LTyClDecl name]
                  , group_roles  :: [LRoleAnnotDecl name] }
        deriving (Typeable)
    deriving instance (DataId id) => Data (TyClGroup id)

    tyClGroupConcat :: [TyClGroup name] -> [LTyClDecl name]
    tyClGroupConcat = concatMap group_tyclds

    mkTyClGroup :: [LTyClDecl name] -> TyClGroup name
    mkTyClGroup decls = TyClGroup { group_tyclds = decls, group_roles = [] }

    type LFamilyDecl name = Located (FamilyDecl name)
    data FamilyDecl name = FamilyDecl
      { fdInfo    :: FamilyInfo name            -- type or data, closed or open
      , fdLName   :: Located name               -- type constructor
      , fdTyVars  :: LHsTyVarBndrs name         -- type variables
      , fdKindSig :: Maybe (LHsKind name) }     -- result kind
      deriving( Typeable )
    deriving instance (DataId id) => Data (FamilyDecl id)

    data FamilyInfo name
      = DataFamily
      | OpenTypeFamily
         -- this list might be empty, if we're in an hs-boot file and the user
         -- said "type family Foo x where .."
      | ClosedTypeFamily [LTyFamInstEqn name]
      deriving( Typeable )
    deriving instance (DataId name) => Data (FamilyInfo name)

    {-
    ------------------------------
    Simple classifiers
    -}

    -- | @True@ <=> argument is a @data@\/@newtype@
    -- declaration.
    isDataDecl :: TyClDecl name -> Bool
    isDataDecl (DataDecl {}) = True
    isDataDecl _other        = False

    -- | type or type instance declaration
    isSynDecl :: TyClDecl name -> Bool
    isSynDecl (SynDecl {})   = True
    isSynDecl _other        = False

    -- | type class
    isClassDecl :: TyClDecl name -> Bool
    isClassDecl (ClassDecl {}) = True
    isClassDecl _              = False

    -- | type/data family declaration
    isFamilyDecl :: TyClDecl name -> Bool
    isFamilyDecl (FamDecl {})  = True
    isFamilyDecl _other        = False

    -- | type family declaration
    isTypeFamilyDecl :: TyClDecl name -> Bool
    isTypeFamilyDecl (FamDecl (FamilyDecl { fdInfo = info })) = case info of
      OpenTypeFamily      -> True
      ClosedTypeFamily {} -> True
      _                   -> False
    isTypeFamilyDecl _ = False

    -- | open type family info
    isOpenTypeFamilyInfo :: FamilyInfo name -> Bool
    isOpenTypeFamilyInfo OpenTypeFamily = True
    isOpenTypeFamilyInfo _              = False

    -- | closed type family info
    isClosedTypeFamilyInfo :: FamilyInfo name -> Bool
    isClosedTypeFamilyInfo (ClosedTypeFamily {}) = True
    isClosedTypeFamilyInfo _                     = False

    -- | data family declaration
    isDataFamilyDecl :: TyClDecl name -> Bool
    isDataFamilyDecl (FamDecl (FamilyDecl { fdInfo = DataFamily })) = True
    isDataFamilyDecl _other      = False

    -- Dealing with names

    tyFamInstDeclName :: OutputableBndr name
                      => TyFamInstDecl name -> name
    tyFamInstDeclName = unLoc . tyFamInstDeclLName

    tyFamInstDeclLName :: OutputableBndr name
                       => TyFamInstDecl name -> Located name
    tyFamInstDeclLName (TyFamInstDecl { tfid_eqn =
                         (L _ (TyFamEqn { tfe_tycon = ln })) })
      = ln

    tyClDeclLName :: TyClDecl name -> Located name
    tyClDeclLName (FamDecl { tcdFam = FamilyDecl { fdLName = ln } }) = ln
    tyClDeclLName decl = tcdLName decl

    tcdName :: TyClDecl name -> name
    tcdName = unLoc . tyClDeclLName

    tyClDeclTyVars :: OutputableBndr name => TyClDecl name -> LHsTyVarBndrs name
    tyClDeclTyVars (FamDecl { tcdFam = FamilyDecl { fdTyVars = tvs } }) = tvs
    tyClDeclTyVars d = tcdTyVars d

    countTyClDecls :: [TyClDecl name] -> (Int, Int, Int, Int, Int)
            -- class, synonym decls, data, newtype, family decls
    countTyClDecls decls
     = (count isClassDecl    decls,
        count isSynDecl      decls,  -- excluding...
        count isDataTy       decls,  -- ...family...
        count isNewTy        decls,  -- ...instances
        count isFamilyDecl   decls)
     where
       isDataTy DataDecl{ tcdDataDefn = HsDataDefn { dd_ND = DataType } } = True
       isDataTy _                                                       = False

       isNewTy DataDecl{ tcdDataDefn = HsDataDefn { dd_ND = NewType } } = True
       isNewTy _                                                      = False

    -- | Does this declaration have a complete, user-supplied kind signature?
    -- See Note [Complete user-supplied kind signatures]
    hsDeclHasCusk :: TyClDecl name -> Bool
    hsDeclHasCusk (FamDecl { tcdFam = fam_decl }) = famDeclHasCusk fam_decl
    hsDeclHasCusk (SynDecl { tcdTyVars = tyvars, tcdRhs = rhs })
      = hsTvbAllKinded tyvars && rhs_annotated rhs
      where
        rhs_annotated (L _ ty) = case ty of
          HsParTy lty  -> rhs_annotated lty
          HsKindSig {} -> True
          _            -> False
    hsDeclHasCusk (DataDecl { tcdTyVars = tyvars })  = hsTvbAllKinded tyvars
    hsDeclHasCusk (ClassDecl { tcdTyVars = tyvars }) = hsTvbAllKinded tyvars

    -- | Does this family declaration have a complete, user-supplied kind signature?
    famDeclHasCusk :: FamilyDecl name -> Bool
    famDeclHasCusk (FamilyDecl { fdInfo = ClosedTypeFamily _
                               , fdTyVars = tyvars
                               , fdKindSig = m_sig })
      = hsTvbAllKinded tyvars && isJust m_sig
    famDeclHasCusk _ = True  -- all open families have CUSKs!

    {-
    Note [Complete user-supplied kind signatures]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    We kind-check declarations differently if they have a complete, user-supplied
    kind signature (CUSK). This is because we can safely generalise a CUSKed
    declaration before checking all of the others, supporting polymorphic recursion.
    See https://ghc.haskell.org/trac/ghc/wiki/GhcKinds/KindInference#Proposednewstrategy
    and #9200 for lots of discussion of how we got here.

    A declaration has a CUSK if we can know its complete kind without doing any inference,
    at all. Here are the rules:

     - A class or datatype is said to have a CUSK if and only if all of its type
    variables are annotated. Its result kind is, by construction, Constraint or *
    respectively.

     - A type synonym has a CUSK if and only if all of its type variables and its
    RHS are annotated with kinds.

     - A closed type family is said to have a CUSK if and only if all of its type
    variables and its return type are annotated.

     - An open type family always has a CUSK -- unannotated type variables (and return type) default to *.
    -}

    instance OutputableBndr name
                  => Outputable (TyClDecl name) where

        ppr (FamDecl { tcdFam = decl }) = ppr decl
        ppr (SynDecl { tcdLName = ltycon, tcdTyVars = tyvars, tcdRhs = rhs })
          = hang (ptext (sLit "type") <+>
                  pp_vanilla_decl_head ltycon tyvars [] <+> equals)
              4 (ppr rhs)

        ppr (DataDecl { tcdLName = ltycon, tcdTyVars = tyvars, tcdDataDefn = defn })
          = pp_data_defn (pp_vanilla_decl_head ltycon tyvars) defn

        ppr (ClassDecl {tcdCtxt = context, tcdLName = lclas, tcdTyVars = tyvars,
                        tcdFDs  = fds,
                        tcdSigs = sigs, tcdMeths = methods,
                        tcdATs = ats, tcdATDefs = at_defs})
          | null sigs && isEmptyBag methods && null ats && null at_defs -- No "where" part
          = top_matter

          | otherwise       -- Laid out
          = vcat [ top_matter <+> ptext (sLit "where")
                 , nest 2 $ pprDeclList (map ppr ats ++
                                         map ppr_fam_deflt_eqn at_defs ++
                                         pprLHsBindsForUser methods sigs) ]
          where
            top_matter = ptext (sLit "class")
                         <+> pp_vanilla_decl_head lclas tyvars (unLoc context)
                         <+> pprFundeps (map unLoc fds)

    instance OutputableBndr name => Outputable (TyClGroup name) where
      ppr (TyClGroup { group_tyclds = tyclds, group_roles = roles })
        = ppr tyclds $$
          ppr roles

    instance (OutputableBndr name) => Outputable (FamilyDecl name) where
      ppr (FamilyDecl { fdInfo = info, fdLName = ltycon,
                        fdTyVars = tyvars, fdKindSig = mb_kind})
          = vcat [ pprFlavour info <+> pp_vanilla_decl_head ltycon tyvars [] <+> pp_kind <+> pp_where
                 , nest 2 $ pp_eqns ]
            where
              pp_kind = case mb_kind of
                          Nothing   -> empty
                          Just kind -> dcolon <+> ppr kind
              (pp_where, pp_eqns) = case info of
                ClosedTypeFamily eqns -> ( ptext (sLit "where")
                                         , if null eqns
                                           then ptext (sLit "..")
                                           else vcat $ map ppr_fam_inst_eqn eqns )
                _                     -> (empty, empty)

    pprFlavour :: FamilyInfo name -> SDoc
    pprFlavour DataFamily            = ptext (sLit "data family")
    pprFlavour OpenTypeFamily        = ptext (sLit "type family")
    pprFlavour (ClosedTypeFamily {}) = ptext (sLit "type family")

    instance Outputable (FamilyInfo name) where
      ppr = pprFlavour

    pp_vanilla_decl_head :: OutputableBndr name
       => Located name
       -> LHsTyVarBndrs name
       -> HsContext name
       -> SDoc
    pp_vanilla_decl_head thing tyvars context
     = hsep [pprHsContext context, pprPrefixOcc (unLoc thing), ppr tyvars]

    pp_fam_inst_lhs :: OutputableBndr name
       => Located name
       -> HsTyPats name
       -> HsContext name
       -> SDoc
    pp_fam_inst_lhs thing (HsWB { hswb_cts = typats }) context -- explicit type patterns
       = hsep [ pprHsContext context, pprPrefixOcc (unLoc thing)
              , hsep (map (pprParendHsType.unLoc) typats)]

    pprTyClDeclFlavour :: TyClDecl a -> SDoc
    pprTyClDeclFlavour (ClassDecl {})   = ptext (sLit "class")
    pprTyClDeclFlavour (SynDecl {})     = ptext (sLit "type")
    pprTyClDeclFlavour (FamDecl { tcdFam = FamilyDecl { fdInfo = info }})
      = pprFlavour info
    pprTyClDeclFlavour (DataDecl { tcdDataDefn = HsDataDefn { dd_ND = nd } })
      = ppr nd

    {-
    ************************************************************************
    *                                                                      *
    \subsection[ConDecl]{A data-constructor declaration}
    *                                                                      *
    ************************************************************************
    -}

    data HsDataDefn name   -- The payload of a data type defn
                           -- Used *both* for vanilla data declarations,
                           --       *and* for data family instances
      = -- | Declares a data type or newtype, giving its constructors
        -- @
        --  data/newtype T a = <constrs>
        --  data/newtype instance T [a] = <constrs>
        -- @
        HsDataDefn { dd_ND     :: NewOrData,
                     dd_ctxt   :: LHsContext name,           -- ^ Context
                     dd_cType  :: Maybe (Located CType),
                     dd_kindSig:: Maybe (LHsKind name),
                         -- ^ Optional kind signature.
                         --
                         -- @(Just k)@ for a GADT-style @data@,
                         -- or @data instance@ decl, with explicit kind sig
                         --
                         -- Always @Nothing@ for H98-syntax decls

                     dd_cons   :: [LConDecl name],
                         -- ^ Data constructors
                         --
                         -- For @data T a = T1 | T2 a@
                         --   the 'LConDecl's all have 'ResTyH98'.
                         -- For @data T a where { T1 :: T a }@
                         --   the 'LConDecls' all have 'ResTyGADT'.

                     dd_derivs :: Maybe (Located [LHsType name])
                         -- ^ Derivings; @Nothing@ => not specified,
                         --              @Just []@ => derive exactly what is asked
                         --
                         -- These "types" must be of form
                         -- @
                         --      forall ab. C ty1 ty2
                         -- @
                         -- Typically the foralls and ty args are empty, but they
                         -- are non-empty for the newtype-deriving case
                         --
                         --  - 'ApiAnnotation.AnnKeywordId' :
                         --       'ApiAnnotation.AnnDeriving',
                         --       'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose'

                 -- For details on above see note [Api annotations] in ApiAnnotation
       }
        deriving( Typeable )
    deriving instance (DataId id) => Data (HsDataDefn id)

    data NewOrData
      = NewType                     -- ^ @newtype Blah ...@
      | DataType                    -- ^ @data Blah ...@
      deriving( Eq, Data, Typeable )                -- Needed because Demand derives Eq

    type LConDecl name = Located (ConDecl name)
          -- ^ May have 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi' when
          --   in a GADT constructor list

      -- For details on above see note [Api annotations] in ApiAnnotation

    -- |
    --
    -- @
    -- data T b = forall a. Eq a => MkT a b
    --   MkT :: forall b a. Eq a => MkT a b
    --
    -- data T b where
    --      MkT1 :: Int -> T Int
    --
    -- data T = Int `MkT` Int
    --        | MkT2
    --
    -- data T a where
    --      Int `MkT` Int :: T Int
    -- @
    --
    -- - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnOpen',
    --            'ApiAnnotation.AnnDotdot','ApiAnnotation.AnnCLose',
    --            'ApiAnnotation.AnnEqual','ApiAnnotation.AnnVbar',
    --            'ApiAnnotation.AnnDarrow','ApiAnnotation.AnnDarrow',
    --            'ApiAnnotation.AnnForall','ApiAnnotation.AnnDot'

    -- For details on above see note [Api annotations] in ApiAnnotation
    data ConDecl name
      = ConDecl
        { con_names     :: [Located name]
            -- ^ Constructor names.  This is used for the DataCon itself, and for
            -- the user-callable wrapper Id.
            -- It is a list to deal with GADT constructors of the form
            --   T1, T2, T3 :: <payload>
        , con_explicit  :: HsExplicitFlag
            -- ^ Is there an user-written forall? (cf. 'HsTypes.HsForAllTy')

        , con_qvars     :: LHsTyVarBndrs name
            -- ^ Type variables.  Depending on 'con_res' this describes the
            -- following entities
            --
            --  - ResTyH98:  the constructor's *existential* type variables
            --  - ResTyGADT: *all* the constructor's quantified type variables
            --
            -- If con_explicit is Implicit, then con_qvars is irrelevant
            -- until after renaming.

        , con_cxt       :: LHsContext name
            -- ^ The context.  This /does not/ include the \"stupid theta\" which
            -- lives only in the 'TyData' decl.

        , con_details   :: HsConDeclDetails name
            -- ^ The main payload

        , con_res       :: ResType (LHsType name)
            -- ^ Result type of the constructor

        , con_doc       :: Maybe LHsDocString
            -- ^ A possible Haddock comment.

        , con_old_rec :: Bool
            -- ^ TEMPORARY field; True <=> user has employed now-deprecated syntax for
            --                             GADT-style record decl   C { blah } :: T a b
            -- Remove this when we no longer parse this stuff, and hence do not
            -- need to report decprecated use
        } deriving (Typeable)
    deriving instance (DataId name) => Data (ConDecl name)

    type HsConDeclDetails name
       = HsConDetails (LBangType name) (Located [LConDeclField name])

    hsConDeclArgTys :: HsConDeclDetails name -> [LBangType name]
    hsConDeclArgTys (PrefixCon tys)    = tys
    hsConDeclArgTys (InfixCon ty1 ty2) = [ty1,ty2]
    hsConDeclArgTys (RecCon flds)      = map (cd_fld_type . unLoc) (unLoc flds)

    data ResType ty
       = ResTyH98             -- Constructor was declared using Haskell 98 syntax
       | ResTyGADT SrcSpan ty -- Constructor was declared using GADT-style syntax,
                              --      and here is its result type, and the SrcSpan
                              --      of the original sigtype, for API Annotations
       deriving (Data, Typeable)

    instance Outputable ty => Outputable (ResType ty) where
             -- Debugging only
       ppr ResTyH98         = ptext (sLit "ResTyH98")
       ppr (ResTyGADT _ ty) = ptext (sLit "ResTyGADT") <+> ppr ty

    pp_data_defn :: OutputableBndr name
                      => (HsContext name -> SDoc)   -- Printing the header
                      -> HsDataDefn name
                      -> SDoc
    pp_data_defn pp_hdr (HsDataDefn { dd_ND = new_or_data, dd_ctxt = L _ context
                                    , dd_kindSig = mb_sig
                                    , dd_cons = condecls, dd_derivs = derivings })
      | null condecls
      = ppr new_or_data <+> pp_hdr context <+> pp_sig

      | otherwise
      = hang (ppr new_or_data <+> pp_hdr context <+> pp_sig)
           2 (pp_condecls condecls $$ pp_derivings)
      where
        pp_sig = case mb_sig of
                   Nothing   -> empty
                   Just kind -> dcolon <+> ppr kind
        pp_derivings = case derivings of
                         Nothing       -> empty
                         Just (L _ ds) -> hsep [ptext (sLit "deriving"),
                                                parens (interpp'SP ds)]

    instance OutputableBndr name => Outputable (HsDataDefn name) where
       ppr d = pp_data_defn (\_ -> ptext (sLit "Naked HsDataDefn")) d

    instance Outputable NewOrData where
      ppr NewType  = ptext (sLit "newtype")
      ppr DataType = ptext (sLit "data")

    pp_condecls :: OutputableBndr name => [LConDecl name] -> SDoc
    pp_condecls cs@(L _ ConDecl{ con_res = ResTyGADT _ _ } : _) -- In GADT syntax
      = hang (ptext (sLit "where")) 2 (vcat (map ppr cs))
    pp_condecls cs                    -- In H98 syntax
      = equals <+> sep (punctuate (ptext (sLit " |")) (map ppr cs))

    instance (OutputableBndr name) => Outputable (ConDecl name) where
        ppr = pprConDecl

    pprConDecl :: OutputableBndr name => ConDecl name -> SDoc
    pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                        , con_cxt = cxt, con_details = details
                        , con_res = ResTyH98, con_doc = doc })
      = sep [ppr_mbDoc doc, pprHsForAll expl tvs cxt, ppr_details details]
      where
        ppr_details (InfixCon t1 t2) = hsep [ppr t1, pprInfixOcc cons, ppr t2]
        ppr_details (PrefixCon tys)  = hsep (pprPrefixOcc cons
                                       : map (pprParendHsType . unLoc) tys)
        ppr_details (RecCon fields)  = ppr_con_names cons
                                     <+> pprConDeclFields (unLoc fields)

    pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                        , con_cxt = cxt, con_details = PrefixCon arg_tys
                        , con_res = ResTyGADT _ res_ty })
      = ppr_con_names cons <+> dcolon <+>
        sep [pprHsForAll expl tvs cxt, ppr (foldr mk_fun_ty res_ty arg_tys)]
      where
        mk_fun_ty a b = noLoc (HsFunTy a b)

    pprConDecl (ConDecl { con_names = cons, con_explicit = expl, con_qvars = tvs
                        , con_cxt = cxt, con_details = RecCon fields
                        , con_res = ResTyGADT _ res_ty })
      = sep [ppr_con_names cons <+> dcolon <+> pprHsForAll expl tvs cxt,
             pprConDeclFields (unLoc fields) <+> arrow <+> ppr res_ty]

    pprConDecl decl@(ConDecl { con_details = InfixCon ty1 ty2, con_res = ResTyGADT {} })
      = pprConDecl (decl { con_details = PrefixCon [ty1,ty2] })
            -- In GADT syntax we don't allow infix constructors
            -- so if we ever trip over one (albeit I can't see how that
            -- can happen) print it like a prefix one

    ppr_con_names :: (OutputableBndr name) => [Located name] -> SDoc
    ppr_con_names [x] = ppr x
    ppr_con_names xs  = interpp'SP xs

    instance (Outputable name) => OutputableBndr [Located name] where
      pprBndr _bs xs = cat $ punctuate comma (map ppr xs)

      pprPrefixOcc [x] = ppr x
      pprPrefixOcc xs  = cat $ punctuate comma (map ppr xs)

      pprInfixOcc [x] = ppr x
      pprInfixOcc xs  = cat $ punctuate comma (map ppr xs)

    {-
    ************************************************************************
    *                                                                      *
                    Instance declarations
    *                                                                      *
    ************************************************************************

    Note [Type family instance declarations in HsSyn]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    The data type TyFamEqn represents one equation of a type family instance.
    It is parameterised over its tfe_pats field:

     * An ordinary type family instance declaration looks like this in source Haskell
          type instance T [a] Int = a -> a
       (or something similar for a closed family)
       It is represented by a TyFamInstEqn, with *type* in the tfe_pats field.

     * On the other hand, the *default instance* of an associated type looksl like
       this in source Haskell
          class C a where
            type T a b
            type T a b = a -> b   -- The default instance
       It is represented by a TyFamDefltEqn, with *type variables8 in the tfe_pats field.
    -}

    ----------------- Type synonym family instances -------------
    type LTyFamInstEqn  name = Located (TyFamInstEqn  name)
      -- ^ May have 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnSemi'
      --   when in a list

    -- For details on above see note [Api annotations] in ApiAnnotation

    type LTyFamDefltEqn name = Located (TyFamDefltEqn name)

    type HsTyPats name = HsWithBndrs name [LHsType name]
                -- ^ Type patterns (with kind and type bndrs)
                -- See Note [Family instance declaration binders]

    type TyFamInstEqn  name = TyFamEqn name (HsTyPats name)
    type TyFamDefltEqn name = TyFamEqn name (LHsTyVarBndrs name)
      -- See Note [Type family instance declarations in HsSyn]

    -- | One equation in a type family instance declaration
    -- See Note [Type family instance declarations in HsSyn]
    data TyFamEqn name pats
      = TyFamEqn
           { tfe_tycon :: Located name
           , tfe_pats  :: pats
           , tfe_rhs   :: LHsType name }
        -- ^
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnEqual'

        -- For details on above see note [Api annotations] in ApiAnnotation
      deriving( Typeable )
    deriving instance (DataId name, Data pats) => Data (TyFamEqn name pats)

    type LTyFamInstDecl name = Located (TyFamInstDecl name)
    data TyFamInstDecl name
      = TyFamInstDecl
           { tfid_eqn  :: LTyFamInstEqn name
           , tfid_fvs  :: PostRn name NameSet }
        -- ^
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
        --           'ApiAnnotation.AnnInstance',

        -- For details on above see note [Api annotations] in ApiAnnotation
      deriving( Typeable )
    deriving instance (DataId name) => Data (TyFamInstDecl name)

    ----------------- Data family instances -------------

    type LDataFamInstDecl name = Located (DataFamInstDecl name)
    data DataFamInstDecl name
      = DataFamInstDecl
           { dfid_tycon :: Located name
           , dfid_pats  :: HsTyPats name      -- LHS
           , dfid_defn  :: HsDataDefn  name   -- RHS
           , dfid_fvs   :: PostRn name NameSet } -- Free vars for
                                                 -- dependency analysis
        -- ^
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnData',
        --           'ApiAnnotation.AnnNewType','ApiAnnotation.AnnInstance',
        --           'ApiAnnotation.AnnDcolon'
        --           'ApiAnnotation.AnnWhere','ApiAnnotation.AnnOpen',
        --           'ApiAnnotation.AnnClose'

        -- For details on above see note [Api annotations] in ApiAnnotation
      deriving( Typeable )
    deriving instance (DataId name) => Data (DataFamInstDecl name)

    ----------------- Class instances -------------

    type LClsInstDecl name = Located (ClsInstDecl name)
    data ClsInstDecl name
      = ClsInstDecl
          { cid_poly_ty :: LHsType name    -- Context => Class Instance-type
                                           -- Using a polytype means that the renamer conveniently
                                           -- figures out the quantified type variables for us.
          , cid_binds         :: LHsBinds name           -- Class methods
          , cid_sigs          :: [LSig name]             -- User-supplied pragmatic info
          , cid_tyfam_insts   :: [LTyFamInstDecl name]   -- Type family instances
          , cid_datafam_insts :: [LDataFamInstDecl name] -- Data family instances
          , cid_overlap_mode  :: Maybe (Located OverlapMode)
             -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
             --                                    'ApiAnnotation.AnnClose',

            -- For details on above see note [Api annotations] in ApiAnnotation
          }
        -- ^
        --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnInstance',
        --           'ApiAnnotation.AnnWhere',
        --           'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose',

        -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId id) => Data (ClsInstDecl id)

    ----------------- Instances of all kinds -------------

    type LInstDecl name = Located (InstDecl name)
    data InstDecl name  -- Both class and family instances
      = ClsInstD
          { cid_inst  :: ClsInstDecl name }
      | DataFamInstD              -- data family instance
          { dfid_inst :: DataFamInstDecl name }
      | TyFamInstD              -- type family instance
          { tfid_inst :: TyFamInstDecl name }
      deriving (Typeable)
    deriving instance (DataId id) => Data (InstDecl id)

    {-
    Note [Family instance declaration binders]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    A {Ty|Data}FamInstDecl is a data/type family instance declaration
    the pats field is LHS patterns, and the tvs of the HsBSig
    tvs are fv(pat_tys), *including* ones that are already in scope

       Eg   class C s t where
              type F t p :: *
            instance C w (a,b) where
              type F (a,b) x = x->a
       The tcdTyVars of the F decl are {a,b,x}, even though the F decl
       is nested inside the 'instance' decl.

       However after the renamer, the uniques will match up:
            instance C w7 (a8,b9) where
              type F (a8,b9) x10 = x10->a8
       so that we can compare the type patter in the 'instance' decl and
       in the associated 'type' decl
    -}

    instance (OutputableBndr name) => Outputable (TyFamInstDecl name) where
      ppr = pprTyFamInstDecl TopLevel

    pprTyFamInstDecl :: OutputableBndr name => TopLevelFlag -> TyFamInstDecl name -> SDoc
    pprTyFamInstDecl top_lvl (TyFamInstDecl { tfid_eqn = eqn })
       = ptext (sLit "type") <+> ppr_instance_keyword top_lvl <+> ppr_fam_inst_eqn eqn

    ppr_instance_keyword :: TopLevelFlag -> SDoc
    ppr_instance_keyword TopLevel    = ptext (sLit "instance")
    ppr_instance_keyword NotTopLevel = empty

    ppr_fam_inst_eqn :: OutputableBndr name => LTyFamInstEqn name -> SDoc
    ppr_fam_inst_eqn (L _ (TyFamEqn { tfe_tycon = tycon
                                    , tfe_pats  = pats
                                    , tfe_rhs   = rhs }))
        = pp_fam_inst_lhs tycon pats [] <+> equals <+> ppr rhs

    ppr_fam_deflt_eqn :: OutputableBndr name => LTyFamDefltEqn name -> SDoc
    ppr_fam_deflt_eqn (L _ (TyFamEqn { tfe_tycon = tycon
                                     , tfe_pats  = tvs
                                     , tfe_rhs   = rhs }))
        = pp_vanilla_decl_head tycon tvs [] <+> equals <+> ppr rhs

    instance (OutputableBndr name) => Outputable (DataFamInstDecl name) where
      ppr = pprDataFamInstDecl TopLevel

    pprDataFamInstDecl :: OutputableBndr name => TopLevelFlag -> DataFamInstDecl name -> SDoc
    pprDataFamInstDecl top_lvl (DataFamInstDecl { dfid_tycon = tycon
                                                , dfid_pats  = pats
                                                , dfid_defn  = defn })
      = pp_data_defn pp_hdr defn
      where
        pp_hdr ctxt = ppr_instance_keyword top_lvl <+> pp_fam_inst_lhs tycon pats ctxt

    pprDataFamInstFlavour :: DataFamInstDecl name -> SDoc
    pprDataFamInstFlavour (DataFamInstDecl { dfid_defn = (HsDataDefn { dd_ND = nd }) })
      = ppr nd

    instance (OutputableBndr name) => Outputable (ClsInstDecl name) where
        ppr (ClsInstDecl { cid_poly_ty = inst_ty, cid_binds = binds
                         , cid_sigs = sigs, cid_tyfam_insts = ats
                         , cid_overlap_mode = mbOverlap
                         , cid_datafam_insts = adts })
          | null sigs, null ats, null adts, isEmptyBag binds  -- No "where" part
          = top_matter

          | otherwise       -- Laid out
          = vcat [ top_matter <+> ptext (sLit "where")
                 , nest 2 $ pprDeclList $
                   map (pprTyFamInstDecl NotTopLevel . unLoc)   ats ++
                   map (pprDataFamInstDecl NotTopLevel . unLoc) adts ++
                   pprLHsBindsForUser binds sigs ]
          where
            top_matter = ptext (sLit "instance") <+> ppOverlapPragma mbOverlap
                                                 <+> ppr inst_ty

    ppOverlapPragma :: Maybe (Located OverlapMode) -> SDoc
    ppOverlapPragma mb =
      case mb of
        Nothing           -> empty
        Just (L _ (NoOverlap _))    -> ptext (sLit "{-# NO_OVERLAP #-}")
        Just (L _ (Overlappable _)) -> ptext (sLit "{-# OVERLAPPABLE #-}")
        Just (L _ (Overlapping _))  -> ptext (sLit "{-# OVERLAPPING #-}")
        Just (L _ (Overlaps _))     -> ptext (sLit "{-# OVERLAPS #-}")
        Just (L _ (Incoherent _))   -> ptext (sLit "{-# INCOHERENT #-}")

    instance (OutputableBndr name) => Outputable (InstDecl name) where
        ppr (ClsInstD     { cid_inst  = decl }) = ppr decl
        ppr (TyFamInstD   { tfid_inst = decl }) = ppr decl
        ppr (DataFamInstD { dfid_inst = decl }) = ppr decl

    -- Extract the declarations of associated data types from an instance

    instDeclDataFamInsts :: [LInstDecl name] -> [DataFamInstDecl name]
    instDeclDataFamInsts inst_decls
      = concatMap do_one inst_decls
      where
        do_one (L _ (ClsInstD { cid_inst = ClsInstDecl { cid_datafam_insts = fam_insts } }))
          = map unLoc fam_insts
        do_one (L _ (DataFamInstD { dfid_inst = fam_inst }))      = [fam_inst]
        do_one (L _ (TyFamInstD {}))                              = []

    {-
    ************************************************************************
    *                                                                      *
    \subsection[DerivDecl]{A stand-alone instance deriving declaration}
    *                                                                      *
    ************************************************************************
    -}

    type LDerivDecl name = Located (DerivDecl name)

    data DerivDecl name = DerivDecl
            { deriv_type :: LHsType name
            , deriv_overlap_mode :: Maybe (Located OverlapMode)
             -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
             --                                    'ApiAnnotation.AnnClose',
             --                                    'ApiAnnotation.AnnDeriving',
             --                                    'ApiAnnotation.AnnInstance'

      -- For details on above see note [Api annotations] in ApiAnnotation
            }
      deriving (Typeable)
    deriving instance (DataId name) => Data (DerivDecl name)

    instance (OutputableBndr name) => Outputable (DerivDecl name) where
        ppr (DerivDecl ty o)
            = hsep [ptext (sLit "deriving instance"), ppOverlapPragma o, ppr ty]

    {-
    ************************************************************************
    *                                                                      *
    \subsection[DefaultDecl]{A @default@ declaration}
    *                                                                      *
    ************************************************************************

    There can only be one default declaration per module, but it is hard
    for the parser to check that; we pass them all through in the abstract
    syntax, and that restriction must be checked in the front end.
    -}

    type LDefaultDecl name = Located (DefaultDecl name)

    data DefaultDecl name
      = DefaultDecl [LHsType name]
            -- ^ - 'ApiAnnotation.AnnKeywordId's : 'ApiAnnotation.AnnDefault',
            --          'ApiAnnotation.AnnOpen','ApiAnnotation.AnnClose'

            -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId name) => Data (DefaultDecl name)

    instance (OutputableBndr name)
                  => Outputable (DefaultDecl name) where

        ppr (DefaultDecl tys)
          = ptext (sLit "default") <+> parens (interpp'SP tys)

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Foreign function interface declaration}
    *                                                                      *
    ************************************************************************
    -}

    -- foreign declarations are distinguished as to whether they define or use a
    -- Haskell name
    --
    --  * the Boolean value indicates whether the pre-standard deprecated syntax
    --   has been used
    --
    type LForeignDecl name = Located (ForeignDecl name)

    data ForeignDecl name
      = ForeignImport (Located name) -- defines this name
                      (LHsType name) -- sig_ty
                      (PostTc name Coercion) -- rep_ty ~ sig_ty
                      ForeignImport
      | ForeignExport (Located name) -- uses this name
                      (LHsType name) -- sig_ty
                      (PostTc name Coercion)  -- sig_ty ~ rep_ty
                      ForeignExport
            -- ^
            --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnForeign',
            --           'ApiAnnotation.AnnImport','ApiAnnotation.AnnExport',
            --           'ApiAnnotation.AnnDcolon'

            -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId name) => Data (ForeignDecl name)
    {-
        In both ForeignImport and ForeignExport:
            sig_ty is the type given in the Haskell code
            rep_ty is the representation for this type, i.e. with newtypes
                   coerced away and type functions evaluated.
        Thus if the declaration is valid, then rep_ty will only use types
        such as Int and IO that we know how to make foreign calls with.
    -}

    noForeignImportCoercionYet :: PlaceHolder
    noForeignImportCoercionYet = PlaceHolder

    noForeignExportCoercionYet :: PlaceHolder
    noForeignExportCoercionYet = PlaceHolder

    -- Specification Of an imported external entity in dependence on the calling
    -- convention
    --
    data ForeignImport = -- import of a C entity
                         --
                         --  * the two strings specifying a header file or library
                         --   may be empty, which indicates the absence of a
                         --   header or object specification (both are not used
                         --   in the case of `CWrapper' and when `CFunction'
                         --   has a dynamic target)
                         --
                         --  * the calling convention is irrelevant for code
                         --   generation in the case of `CLabel', but is needed
                         --   for pretty printing
                         --
                         --  * `Safety' is irrelevant for `CLabel' and `CWrapper'
                         --
                         CImport  (Located CCallConv) -- ccall or stdcall
                                  (Located Safety)  -- interruptible, safe or unsafe
                                  (Maybe Header)       -- name of C header
                                  CImportSpec          -- details of the C entity
                                  (Located SourceText) -- original source text for
                                                       -- the C entity
      deriving (Data, Typeable)

    -- details of an external C entity
    --
    data CImportSpec = CLabel    CLabelString     -- import address of a C label
                     | CFunction CCallTarget      -- static or dynamic function
                     | CWrapper                   -- wrapper to expose closures
                                                  -- (former f.e.d.)
      deriving (Data, Typeable)

    -- specification of an externally exported entity in dependence on the calling
    -- convention
    --
    data ForeignExport = CExport  (Located CExportSpec) -- contains the calling
                                                        -- convention
                                  (Located SourceText)  -- original source text for
                                                        -- the C entity
      deriving (Data, Typeable)

    -- pretty printing of foreign declarations
    --

    instance OutputableBndr name => Outputable (ForeignDecl name) where
      ppr (ForeignImport n ty _ fimport) =
        hang (ptext (sLit "foreign import") <+> ppr fimport <+> ppr n)
           2 (dcolon <+> ppr ty)
      ppr (ForeignExport n ty _ fexport) =
        hang (ptext (sLit "foreign export") <+> ppr fexport <+> ppr n)
           2 (dcolon <+> ppr ty)

    instance Outputable ForeignImport where
      ppr (CImport  cconv safety mHeader spec _) =
        ppr cconv <+> ppr safety <+>
        char '"' <> pprCEntity spec <> char '"'
        where
          pp_hdr = case mHeader of
                   Nothing -> empty
                   Just (Header header) -> ftext header

          pprCEntity (CLabel lbl) =
            ptext (sLit "static") <+> pp_hdr <+> char '&' <> ppr lbl
          pprCEntity (CFunction (StaticTarget lbl _ isFun)) =
                ptext (sLit "static")
            <+> pp_hdr
            <+> (if isFun then empty else ptext (sLit "value"))
            <+> ppr lbl
          pprCEntity (CFunction (DynamicTarget)) =
            ptext (sLit "dynamic")
          pprCEntity (CWrapper) = ptext (sLit "wrapper")

    instance Outputable ForeignExport where
      ppr (CExport  (L _ (CExportStatic lbl cconv)) _) =
        ppr cconv <+> char '"' <> ppr lbl <> char '"'

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Transformation rules}
    *                                                                      *
    ************************************************************************
    -}

    type LRuleDecls name = Located (RuleDecls name)

      -- Note [Pragma source text] in BasicTypes
    data RuleDecls name = HsRules { rds_src   :: SourceText
                                  , rds_rules :: [LRuleDecl name] }
      deriving (Typeable)
    deriving instance (DataId name) => Data (RuleDecls name)

    type LRuleDecl name = Located (RuleDecl name)

    data RuleDecl name
      = HsRule                      -- Source rule
            (Located RuleName)      -- Rule name
            Activation
            [LRuleBndr name]        -- Forall'd vars; after typechecking this
                                    --   includes tyvars
            (Located (HsExpr name)) -- LHS
            (PostRn name NameSet)   -- Free-vars from the LHS
            (Located (HsExpr name)) -- RHS
            (PostRn name NameSet)   -- Free-vars from the RHS
            -- ^
            --  - 'ApiAnnotation.AnnKeywordId' :
            --           'ApiAnnotation.AnnOpen','ApiAnnotation.AnnTilde',
            --           'ApiAnnotation.AnnVal',
            --           'ApiAnnotation.AnnClose',
            --           'ApiAnnotation.AnnForall','ApiAnnotation.AnnDot',
            --           'ApiAnnotation.AnnEqual',

            -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId name) => Data (RuleDecl name)

    flattenRuleDecls :: [LRuleDecls name] -> [LRuleDecl name]
    flattenRuleDecls decls = concatMap (rds_rules . unLoc) decls

    type LRuleBndr name = Located (RuleBndr name)
    data RuleBndr name
      = RuleBndr (Located name)
      | RuleBndrSig (Located name) (HsWithBndrs name (LHsType name))
            -- ^
            --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
            --     'ApiAnnotation.AnnDcolon','ApiAnnotation.AnnClose'

            -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId name) => Data (RuleBndr name)

    collectRuleBndrSigTys :: [RuleBndr name] -> [HsWithBndrs name (LHsType name)]
    collectRuleBndrSigTys bndrs = [ty | RuleBndrSig _ ty <- bndrs]

    instance OutputableBndr name => Outputable (RuleDecls name) where
      ppr (HsRules _ rules) = ppr rules

    instance OutputableBndr name => Outputable (RuleDecl name) where
      ppr (HsRule name act ns lhs _fv_lhs rhs _fv_rhs)
            = sep [text "{-# RULES" <+> doubleQuotes (ftext $ unLoc name)
                                    <+> ppr act,
                   nest 4 (pp_forall <+> pprExpr (unLoc lhs)),
                   nest 4 (equals <+> pprExpr (unLoc rhs) <+> text "#-}") ]
            where
              pp_forall | null ns   = empty
                        | otherwise = forAllLit <+> fsep (map ppr ns) <> dot

    instance OutputableBndr name => Outputable (RuleBndr name) where
       ppr (RuleBndr name) = ppr name
       ppr (RuleBndrSig name ty) = ppr name <> dcolon <> ppr ty

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Vectorisation declarations}
    *                                                                      *
    ************************************************************************

    A vectorisation pragma, one of

      {-# VECTORISE f = closure1 g (scalar_map g) #-}
      {-# VECTORISE SCALAR f #-}
      {-# NOVECTORISE f #-}

      {-# VECTORISE type T = ty #-}
      {-# VECTORISE SCALAR type T #-}
    -}

    type LVectDecl name = Located (VectDecl name)

    data VectDecl name
      = HsVect
          SourceText   -- Note [Pragma source text] in BasicTypes
          (Located name)
          (LHsExpr name)
            -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
            --           'ApiAnnotation.AnnEqual','ApiAnnotation.AnnClose'

            -- For details on above see note [Api annotations] in ApiAnnotation
      | HsNoVect
          SourceText   -- Note [Pragma source text] in BasicTypes
          (Located name)
            -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
            --                                    'ApiAnnotation.AnnClose'

            -- For details on above see note [Api annotations] in ApiAnnotation
      | HsVectTypeIn                -- pre type-checking
          SourceText                -- Note [Pragma source text] in BasicTypes
          Bool                      -- 'TRUE' => SCALAR declaration
          (Located name)
          (Maybe (Located name))    -- 'Nothing' => no right-hand side
            -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
            --           'ApiAnnotation.AnnType','ApiAnnotation.AnnClose',
            --           'ApiAnnotation.AnnEqual'

            -- For details on above see note [Api annotations] in ApiAnnotation
      | HsVectTypeOut               -- post type-checking
          Bool                      -- 'TRUE' => SCALAR declaration
          TyCon
          (Maybe TyCon)             -- 'Nothing' => no right-hand side
      | HsVectClassIn               -- pre type-checking
          SourceText                -- Note [Pragma source text] in BasicTypes
          (Located name)
            -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
            --           'ApiAnnotation.AnnClass','ApiAnnotation.AnnClose',

           -- For details on above see note [Api annotations] in ApiAnnotation
      | HsVectClassOut              -- post type-checking
          Class
      | HsVectInstIn                -- pre type-checking (always SCALAR)  !!!FIXME: should be superfluous now
          (LHsType name)
      | HsVectInstOut               -- post type-checking (always SCALAR) !!!FIXME: should be superfluous now
          ClsInst
      deriving (Typeable)
    deriving instance (DataId name) => Data (VectDecl name)

    lvectDeclName :: NamedThing name => LVectDecl name -> Name
    lvectDeclName (L _ (HsVect _       (L _ name) _))    = getName name
    lvectDeclName (L _ (HsNoVect _     (L _ name)))      = getName name
    lvectDeclName (L _ (HsVectTypeIn _  _ (L _ name) _)) = getName name
    lvectDeclName (L _ (HsVectTypeOut  _ tycon _))       = getName tycon
    lvectDeclName (L _ (HsVectClassIn _ (L _ name)))     = getName name
    lvectDeclName (L _ (HsVectClassOut cls))             = getName cls
    lvectDeclName (L _ (HsVectInstIn _))
      = panic "HsDecls.lvectDeclName: HsVectInstIn"
    lvectDeclName (L _ (HsVectInstOut  _))
      = panic "HsDecls.lvectDeclName: HsVectInstOut"

    lvectInstDecl :: LVectDecl name -> Bool
    lvectInstDecl (L _ (HsVectInstIn _))  = True
    lvectInstDecl (L _ (HsVectInstOut _)) = True
    lvectInstDecl _                       = False

    instance OutputableBndr name => Outputable (VectDecl name) where
      ppr (HsVect _ v rhs)
        = sep [text "{-# VECTORISE" <+> ppr v,
               nest 4 $
                 pprExpr (unLoc rhs) <+> text "#-}" ]
      ppr (HsNoVect _ v)
        = sep [text "{-# NOVECTORISE" <+> ppr v <+> text "#-}" ]
      ppr (HsVectTypeIn _ False t Nothing)
        = sep [text "{-# VECTORISE type" <+> ppr t <+> text "#-}" ]
      ppr (HsVectTypeIn _ False t (Just t'))
        = sep [text "{-# VECTORISE type" <+> ppr t, text "=", ppr t', text "#-}" ]
      ppr (HsVectTypeIn _ True t Nothing)
        = sep [text "{-# VECTORISE SCALAR type" <+> ppr t <+> text "#-}" ]
      ppr (HsVectTypeIn _ True t (Just t'))
        = sep [text "{-# VECTORISE SCALAR type" <+> ppr t, text "=", ppr t', text "#-}" ]
      ppr (HsVectTypeOut False t Nothing)
        = sep [text "{-# VECTORISE type" <+> ppr t <+> text "#-}" ]
      ppr (HsVectTypeOut False t (Just t'))
        = sep [text "{-# VECTORISE type" <+> ppr t, text "=", ppr t', text "#-}" ]
      ppr (HsVectTypeOut True t Nothing)
        = sep [text "{-# VECTORISE SCALAR type" <+> ppr t <+> text "#-}" ]
      ppr (HsVectTypeOut True t (Just t'))
        = sep [text "{-# VECTORISE SCALAR type" <+> ppr t, text "=", ppr t', text "#-}" ]
      ppr (HsVectClassIn _ c)
        = sep [text "{-# VECTORISE class" <+> ppr c <+> text "#-}" ]
      ppr (HsVectClassOut c)
        = sep [text "{-# VECTORISE class" <+> ppr c <+> text "#-}" ]
      ppr (HsVectInstIn ty)
        = sep [text "{-# VECTORISE SCALAR instance" <+> ppr ty <+> text "#-}" ]
      ppr (HsVectInstOut i)
        = sep [text "{-# VECTORISE SCALAR instance" <+> ppr i <+> text "#-}" ]

    {-
    ************************************************************************
    *                                                                      *
    \subsection[DocDecl]{Document comments}
    *                                                                      *
    ************************************************************************
    -}

    type LDocDecl = Located (DocDecl)

    data DocDecl
      = DocCommentNext HsDocString
      | DocCommentPrev HsDocString
      | DocCommentNamed String HsDocString
      | DocGroup Int HsDocString
      deriving (Data, Typeable)

    -- Okay, I need to reconstruct the document comments, but for now:
    instance Outputable DocDecl where
      ppr _ = text "<document comment>"

    docDeclDoc :: DocDecl -> HsDocString
    docDeclDoc (DocCommentNext d) = d
    docDeclDoc (DocCommentPrev d) = d
    docDeclDoc (DocCommentNamed _ d) = d
    docDeclDoc (DocGroup _ d) = d

    {-
    ************************************************************************
    *                                                                      *
    \subsection[DeprecDecl]{Deprecations}
    *                                                                      *
    ************************************************************************

    We use exported entities for things to deprecate.
    -}

    type LWarnDecls name = Located (WarnDecls name)

     -- Note [Pragma source text] in BasicTypes
    data WarnDecls name = Warnings { wd_src :: SourceText
                                   , wd_warnings :: [LWarnDecl name]
                                   }
      deriving (Data, Typeable)

    type LWarnDecl name = Located (WarnDecl name)

    data WarnDecl name = Warning [Located name] WarningTxt
      deriving (Data, Typeable)

    instance OutputableBndr name => Outputable (WarnDecls name) where
        ppr (Warnings _ decls) = ppr decls

    instance OutputableBndr name => Outputable (WarnDecl name) where
        ppr (Warning thing txt)
          = hsep [text "{-# DEPRECATED", ppr thing, doubleQuotes (ppr txt), text "#-}"]

    {-
    ************************************************************************
    *                                                                      *
    \subsection[AnnDecl]{Annotations}
    *                                                                      *
    ************************************************************************
    -}

    type LAnnDecl name = Located (AnnDecl name)

    data AnnDecl name = HsAnnotation
                          SourceText -- Note [Pragma source text] in BasicTypes
                          (AnnProvenance name) (Located (HsExpr name))
          -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnOpen',
          --           'ApiAnnotation.AnnType'
          --           'ApiAnnotation.AnnModule'
          --           'ApiAnnotation.AnnClose'

          -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Typeable)
    deriving instance (DataId name) => Data (AnnDecl name)

    instance (OutputableBndr name) => Outputable (AnnDecl name) where
        ppr (HsAnnotation _ provenance expr)
          = hsep [text "{-#", pprAnnProvenance provenance, pprExpr (unLoc expr), text "#-}"]

    data AnnProvenance name = ValueAnnProvenance (Located name)
                            | TypeAnnProvenance (Located name)
                            | ModuleAnnProvenance
      deriving (Data, Typeable, Functor)
    deriving instance Foldable    AnnProvenance
    deriving instance Traversable AnnProvenance

    annProvenanceName_maybe :: AnnProvenance name -> Maybe name
    annProvenanceName_maybe (ValueAnnProvenance (L _ name)) = Just name
    annProvenanceName_maybe (TypeAnnProvenance (L _ name))  = Just name
    annProvenanceName_maybe ModuleAnnProvenance       = Nothing

    pprAnnProvenance :: OutputableBndr name => AnnProvenance name -> SDoc
    pprAnnProvenance ModuleAnnProvenance       = ptext (sLit "ANN module")
    pprAnnProvenance (ValueAnnProvenance (L _ name))
      = ptext (sLit "ANN") <+> ppr name
    pprAnnProvenance (TypeAnnProvenance (L _ name))
      = ptext (sLit "ANN type") <+> ppr name

    {-
    ************************************************************************
    *                                                                      *
    \subsection[RoleAnnot]{Role annotations}
    *                                                                      *
    ************************************************************************
    -}

    type LRoleAnnotDecl name = Located (RoleAnnotDecl name)

    -- See #8185 for more info about why role annotations are
    -- top-level declarations
    data RoleAnnotDecl name
      = RoleAnnotDecl (Located name)         -- type constructor
                      [Located (Maybe Role)] -- optional annotations
          -- ^ - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
          --           'ApiAnnotation.AnnRole'

          -- For details on above see note [Api annotations] in ApiAnnotation
      deriving (Data, Typeable)

    instance OutputableBndr name => Outputable (RoleAnnotDecl name) where
      ppr (RoleAnnotDecl ltycon roles)
        = ptext (sLit "type role") <+> ppr ltycon <+>
          hsep (map (pp_role . unLoc) roles)
        where
          pp_role Nothing  = underscore
          pp_role (Just r) = ppr r

    roleAnnotDeclName :: RoleAnnotDecl name -> name
    roleAnnotDeclName (RoleAnnotDecl (L _ name) _) = name