    {-# LANGUAGE CPP                 #-}
    {-# LANGUAGE FlexibleContexts    #-}
    {-# LANGUAGE RankNTypes          #-}
    {-# LANGUAGE ScopedTypeVariables #-}
    {-# LANGUAGE TypeApplications    #-}
    {-# LANGUAGE TypeFamilies        #-}

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

    -}

    module GHC.Tc.Gen.Bind
       ( tcLocalBinds
       , tcTopBinds
       , tcValBinds
       , tcHsBootSigs
       , tcPolyCheck
       , chooseInferredQuantifiers
       , badBootDeclErr
       )
    where

    import GHC.Prelude

    import {-# SOURCE #-} GHC.Tc.Gen.Match ( tcGRHSsPat, tcMatchesFun )
    import {-# SOURCE #-} GHC.Tc.Gen.Expr  ( tcCheckMonoExpr )
    import {-# SOURCE #-} GHC.Tc.TyCl.PatSyn ( tcPatSynDecl, tcPatSynBuilderBind )

    import GHC.Types.Tickish (CoreTickish, GenTickish (..))
    import GHC.Types.CostCentre (mkUserCC, CCFlavour(DeclCC))
    import GHC.Driver.Session
    import GHC.Data.FastString
    import GHC.Hs
    import GHC.Tc.Gen.Sig
    import GHC.Tc.Utils.Monad
    import GHC.Tc.Types.Origin
    import GHC.Tc.Utils.Env
    import GHC.Tc.Utils.Unify
    import GHC.Tc.Solver
    import GHC.Tc.Types.Evidence
    import GHC.Tc.Gen.HsType
    import GHC.Tc.Gen.Pat
    import GHC.Tc.Utils.TcMType
    import GHC.Core.Multiplicity
    import GHC.Core.FamInstEnv( normaliseType )
    import GHC.Tc.Instance.Family( tcGetFamInstEnvs )
    import GHC.Tc.Utils.TcType
    import GHC.Core.Type (mkStrLitTy, tidyOpenType, mkCastTy)
    import GHC.Builtin.Types ( mkBoxedTupleTy )
    import GHC.Builtin.Types.Prim
    import GHC.Types.SourceText
    import GHC.Types.Id
    import GHC.Types.Var as Var
    import GHC.Types.Var.Set
    import GHC.Types.Var.Env( TidyEnv )
    import GHC.Unit.Module
    import GHC.Types.Name
    import GHC.Types.Name.Set
    import GHC.Types.Name.Env
    import GHC.Types.SrcLoc
    import GHC.Data.Bag
    import GHC.Utils.Error
    import GHC.Data.Graph.Directed
    import GHC.Data.Maybe
    import GHC.Utils.Misc
    import GHC.Types.Basic
    import GHC.Types.CompleteMatch
    import GHC.Utils.Outputable as Outputable
    import GHC.Utils.Panic
    import GHC.Builtin.Names( ipClassName )
    import GHC.Tc.Validity (checkValidType)
    import GHC.Types.Unique.FM
    import GHC.Types.Unique.DSet
    import GHC.Types.Unique.Set
    import qualified GHC.LanguageExtensions as LangExt

    import Control.Monad
    import Data.Foldable (find)

    #include "HsVersions.h"

    {-
    ************************************************************************
    *                                                                      *
    \subsection{Type-checking bindings}
    *                                                                      *
    ************************************************************************

    @tcBindsAndThen@ typechecks a @HsBinds@.  The "and then" part is because
    it needs to know something about the {\em usage} of the things bound,
    so that it can create specialisations of them.  So @tcBindsAndThen@
    takes a function which, given an extended environment, E, typechecks
    the scope of the bindings returning a typechecked thing and (most
    important) an LIE.  It is this LIE which is then used as the basis for
    specialising the things bound.

    @tcBindsAndThen@ also takes a "combiner" which glues together the
    bindings and the "thing" to make a new "thing".

    The real work is done by @tcBindWithSigsAndThen@.

    Recursive and non-recursive binds are handled in essentially the same
    way: because of uniques there are no scoping issues left.  The only
    difference is that non-recursive bindings can bind primitive values.

    Even for non-recursive binding groups we add typings for each binder
    to the LVE for the following reason.  When each individual binding is
    checked the type of its LHS is unified with that of its RHS; and
    type-checking the LHS of course requires that the binder is in scope.

    At the top-level the LIE is sure to contain nothing but constant
    dictionaries, which we resolve at the module level.

    Note [Polymorphic recursion]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    The game plan for polymorphic recursion in the code above is

            * Bind any variable for which we have a type signature
              to an Id with a polymorphic type.  Then when type-checking
              the RHSs we'll make a full polymorphic call.

    This fine, but if you aren't a bit careful you end up with a horrendous
    amount of partial application and (worse) a huge space leak. For example:

            f :: Eq a => [a] -> [a]
            f xs = ...f...

    If we don't take care, after typechecking we get

            f = /\a -> \d::Eq a -> let f' = f a d
                                   in
                                   \ys:[a] -> ...f'...

    Notice the stupid construction of (f a d), which is of course
    identical to the function we're executing.  In this case, the
    polymorphic recursion isn't being used (but that's a very common case).
    This can lead to a massive space leak, from the following top-level defn
    (post-typechecking)

            ff :: [Int] -> [Int]
            ff = f Int dEqInt

    Now (f dEqInt) evaluates to a lambda that has f' as a free variable; but
    f' is another thunk which evaluates to the same thing... and you end
    up with a chain of identical values all hung onto by the CAF ff.

            ff = f Int dEqInt

               = let f' = f Int dEqInt in \ys. ...f'...

               = let f' = let f' = f Int dEqInt in \ys. ...f'...
                          in \ys. ...f'...

    Etc.

    NOTE: a bit of arity analysis would push the (f a d) inside the (\ys...),
    which would make the space leak go away in this case

    Solution: when typechecking the RHSs we always have in hand the
    *monomorphic* Ids for each binding.  So we just need to make sure that
    if (Method f a d) shows up in the constraints emerging from (...f...)
    we just use the monomorphic Id.  We achieve this by adding monomorphic Ids
    to the "givens" when simplifying constraints.  That's what the "lies_avail"
    is doing.

    Then we get

            f = /\a -> \d::Eq a -> letrec
                                     fm = \ys:[a] -> ...fm...
                                   in
                                   fm
    -}

    tcTopBinds :: [(RecFlag, LHsBinds GhcRn)] -> [LSig GhcRn]
               -> TcM (TcGblEnv, TcLclEnv)
    -- The TcGblEnv contains the new tcg_binds and tcg_spects
    -- The TcLclEnv has an extended type envt for the new bindings
    tcTopBinds :: [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn] -> TcM (TcGblEnv, TcLclEnv)
    tcTopBinds [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs
      = do  { -- Pattern synonym bindings populate the global environment
              ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    binds', (TcGblEnv
    tcg_env, TcLclEnv
    tcl_env)) <- TopLevelFlag
    -> [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn]
    -> TcM (TcGblEnv, TcLclEnv)
    -> TcM ([(RecFlag, LHsBinds GhcTc)], (TcGblEnv, TcLclEnv))
    forall thing.
    TopLevelFlag
    -> [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcValBinds TopLevelFlag
    TopLevel [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs (TcM (TcGblEnv, TcLclEnv)
     -> TcM ([(RecFlag, LHsBinds GhcTc)], (TcGblEnv, TcLclEnv)))
    -> TcM (TcGblEnv, TcLclEnv)
    -> TcM ([(RecFlag, LHsBinds GhcTc)], (TcGblEnv, TcLclEnv))
    forall a b. (a -> b) -> a -> b
    $
                do { TcGblEnv
    gbl <- TcRnIf TcGblEnv TcLclEnv TcGblEnv
    forall gbl lcl. TcRnIf gbl lcl gbl
    getGblEnv
                   ; TcLclEnv
    lcl <- TcRnIf TcGblEnv TcLclEnv TcLclEnv
    forall gbl lcl. TcRnIf gbl lcl lcl
    getLclEnv
                   ; (TcGblEnv, TcLclEnv) -> TcM (TcGblEnv, TcLclEnv)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TcGblEnv
    gbl, TcLclEnv
    lcl) }
            ; [LTcSpecPrag]
    specs <- [LSig GhcRn] -> TcM [LTcSpecPrag]
    tcImpPrags [LSig GhcRn]
    sigs   -- SPECIALISE prags for imported Ids

            ; [CompleteMatch]
    complete_matches <- (TcGblEnv, TcLclEnv)
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    forall gbl' lcl' a gbl lcl.
    (gbl', lcl') -> TcRnIf gbl' lcl' a -> TcRnIf gbl lcl a
    setEnvs (TcGblEnv
    tcg_env, TcLclEnv
    tcl_env) (TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
     -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch])
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    forall a b. (a -> b) -> a -> b
    $ [LSig GhcRn] -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    tcCompleteSigs [LSig GhcRn]
    sigs
            ; String -> SDoc -> TcRn ()
    traceTc String
    "complete_matches" ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    [(RecFlag, LHsBinds GhcRn)]
    binds SDoc -> SDoc -> SDoc
    $$ [GenLocated SrcSpanAnnA (Sig GhcRn)] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [GenLocated SrcSpanAnnA (Sig GhcRn)]
    [LSig GhcRn]
    sigs)
            ; String -> SDoc -> TcRn ()
    traceTc String
    "complete_matches" ([CompleteMatch] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [CompleteMatch]
    complete_matches)

            ; let { tcg_env' :: TcGblEnv
    tcg_env' = TcGblEnv
    tcg_env { tcg_imp_specs :: [LTcSpecPrag]
    tcg_imp_specs
                                          = [LTcSpecPrag]
    specs [LTcSpecPrag] -> [LTcSpecPrag] -> [LTcSpecPrag]
    forall a. [a] -> [a] -> [a]
    ++ TcGblEnv -> [LTcSpecPrag]
    tcg_imp_specs TcGblEnv
    tcg_env
                                       , tcg_complete_matches :: [CompleteMatch]
    tcg_complete_matches
                                          = [CompleteMatch]
    complete_matches
                                              [CompleteMatch] -> [CompleteMatch] -> [CompleteMatch]
    forall a. [a] -> [a] -> [a]
    ++ TcGblEnv -> [CompleteMatch]
    tcg_complete_matches TcGblEnv
    tcg_env }
                               TcGblEnv -> [LHsBinds GhcTc] -> TcGblEnv
    `addTypecheckedBinds` ((RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    -> [Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))]
    forall a b. (a -> b) -> [a] -> [b]
    map (RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a b. (a, b) -> b
    snd [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    binds' }

            ; (TcGblEnv, TcLclEnv) -> TcM (TcGblEnv, TcLclEnv)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TcGblEnv
    tcg_env', TcLclEnv
    tcl_env) }
            -- The top level bindings are flattened into a giant
            -- implicitly-mutually-recursive LHsBinds

    tcCompleteSigs  :: [LSig GhcRn] -> TcM [CompleteMatch]
    tcCompleteSigs :: [LSig GhcRn] -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    tcCompleteSigs [LSig GhcRn]
    sigs =
      let
          doOne :: LSig GhcRn -> TcM (Maybe CompleteMatch)
          -- We don't need to "type-check" COMPLETE signatures anymore; if their
          -- combinations are invalid it will be found so at match sites.
          -- There it is also where we consider if the type of the pattern match is
          -- compatible with the result type constructor 'mb_tc'.
          doOne :: LSig GhcRn -> TcM (Maybe CompleteMatch)
    doOne (L SrcSpanAnnA
    loc c :: Sig GhcRn
    c@(CompleteMatchSig XCompleteMatchSig GhcRn
    _ext SourceText
    _src_txt (L SrcSpan
    _ [GenLocated SrcSpanAnnN Name]
    ns) Maybe (LIdP GhcRn)
    mb_tc_nm))
            = (CompleteMatch -> Maybe CompleteMatch)
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> TcM (Maybe CompleteMatch)
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap CompleteMatch -> Maybe CompleteMatch
    forall a. a -> Maybe a
    Just (IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
     -> TcM (Maybe CompleteMatch))
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> TcM (Maybe CompleteMatch)
    forall a b. (a -> b) -> a -> b
    $ SrcSpanAnnA
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
    setSrcSpanA SrcSpanAnnA
    loc (IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
     -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch)
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    forall a b. (a -> b) -> a -> b
    $ SDoc
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    forall a. SDoc -> TcM a -> TcM a
    addErrCtxt (String -> SDoc
    text String
    "In" SDoc -> SDoc -> SDoc
    <+> Sig GhcRn -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Sig GhcRn
    c) (IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
     -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch)
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    forall a b. (a -> b) -> a -> b
    $ do
                UniqDSet ConLike
    cls   <- [ConLike] -> UniqDSet ConLike
    forall a. Uniquable a => [a] -> UniqDSet a
    mkUniqDSet ([ConLike] -> UniqDSet ConLike)
    -> IOEnv (Env TcGblEnv TcLclEnv) [ConLike]
    -> IOEnv (Env TcGblEnv TcLclEnv) (UniqDSet ConLike)
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> (GenLocated SrcSpanAnnN Name
     -> IOEnv (Env TcGblEnv TcLclEnv) ConLike)
    -> [GenLocated SrcSpanAnnN Name]
    -> IOEnv (Env TcGblEnv TcLclEnv) [ConLike]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM ((Name -> IOEnv (Env TcGblEnv TcLclEnv) ConLike)
    -> GenLocated SrcSpanAnnN Name
    -> IOEnv (Env TcGblEnv TcLclEnv) ConLike
    forall a b ann.
    (a -> TcM b) -> GenLocated (SrcSpanAnn' ann) a -> TcM b
    addLocMA Name -> IOEnv (Env TcGblEnv TcLclEnv) ConLike
    tcLookupConLike) [GenLocated SrcSpanAnnN Name]
    ns
                Maybe TyCon
    mb_tc <- forall (t :: * -> *) (f :: * -> *) a b.
    (Traversable t, Applicative f) =>
    (a -> f b) -> t a -> f (t b)
    traverse @Maybe GenLocated SrcSpanAnnN Name -> IOEnv (Env TcGblEnv TcLclEnv) TyCon
    tcLookupLocatedTyCon Maybe (GenLocated SrcSpanAnnN Name)
    Maybe (LIdP GhcRn)
    mb_tc_nm
                CompleteMatch -> IOEnv (Env TcGblEnv TcLclEnv) CompleteMatch
    forall (f :: * -> *) a. Applicative f => a -> f a
    pure CompleteMatch { cmConLikes :: UniqDSet ConLike
    cmConLikes = UniqDSet ConLike
    cls, cmResultTyCon :: Maybe TyCon
    cmResultTyCon = Maybe TyCon
    mb_tc }
          doOne LSig GhcRn
    _ = Maybe CompleteMatch -> TcM (Maybe CompleteMatch)
    forall (m :: * -> *) a. Monad m => a -> m a
    return Maybe CompleteMatch
    forall a. Maybe a
    Nothing

      -- For some reason I haven't investigated further, the signatures come in
      -- backwards wrt. declaration order. So we reverse them here, because it makes
      -- a difference for incomplete match suggestions.
      in (GenLocated SrcSpanAnnA (Sig GhcRn) -> TcM (Maybe CompleteMatch))
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)]
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    forall (m :: * -> *) a b.
    Applicative m =>
    (a -> m (Maybe b)) -> [a] -> m [b]
    mapMaybeM GenLocated SrcSpanAnnA (Sig GhcRn) -> TcM (Maybe CompleteMatch)
    LSig GhcRn -> TcM (Maybe CompleteMatch)
    doOne ([GenLocated SrcSpanAnnA (Sig GhcRn)]
     -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch])
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)]
    -> TcRnIf TcGblEnv TcLclEnv [CompleteMatch]
    forall a b. (a -> b) -> a -> b
    $ [GenLocated SrcSpanAnnA (Sig GhcRn)]
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)]
    forall a. [a] -> [a]
    reverse [GenLocated SrcSpanAnnA (Sig GhcRn)]
    [LSig GhcRn]
    sigs

    tcHsBootSigs :: [(RecFlag, LHsBinds GhcRn)] -> [LSig GhcRn] -> TcM [Id]
    -- A hs-boot file has only one BindGroup, and it only has type
    -- signatures in it.  The renamer checked all this
    tcHsBootSigs :: [(RecFlag, LHsBinds GhcRn)] -> [LSig GhcRn] -> TcM [TcId]
    tcHsBootSigs [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs
      = do  { Bool -> SDoc -> TcRn ()
    checkTc ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    [(RecFlag, LHsBinds GhcRn)]
    binds) SDoc
    badBootDeclErr
            ; (GenLocated SrcSpanAnnA (Sig GhcRn) -> TcM [TcId])
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)] -> TcM [TcId]
    forall (m :: * -> *) a b. Monad m => (a -> m [b]) -> [a] -> m [b]
    concatMapM ((Sig GhcRn -> TcM [TcId])
    -> GenLocated SrcSpanAnnA (Sig GhcRn) -> TcM [TcId]
    forall a b ann.
    (a -> TcM b) -> GenLocated (SrcSpanAnn' ann) a -> TcM b
    addLocMA Sig GhcRn -> TcM [TcId]
    tc_boot_sig) ((GenLocated SrcSpanAnnA (Sig GhcRn) -> Bool)
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)]
    -> [GenLocated SrcSpanAnnA (Sig GhcRn)]
    forall a. (a -> Bool) -> [a] -> [a]
    filter GenLocated SrcSpanAnnA (Sig GhcRn) -> Bool
    forall p. UnXRec p => LSig p -> Bool
    isTypeLSig [GenLocated SrcSpanAnnA (Sig GhcRn)]
    [LSig GhcRn]
    sigs) }
      where
        tc_boot_sig :: Sig GhcRn -> TcM [TcId]
    tc_boot_sig (TypeSig XTypeSig GhcRn
    _ [LIdP GhcRn]
    lnames LHsSigWcType GhcRn
    hs_ty) = (GenLocated SrcSpanAnnN Name -> IOEnv (Env TcGblEnv TcLclEnv) TcId)
    -> [GenLocated SrcSpanAnnN Name] -> TcM [TcId]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM GenLocated SrcSpanAnnN Name -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    f [GenLocated SrcSpanAnnN Name]
    [LIdP GhcRn]
    lnames
          where
            f :: GenLocated SrcSpanAnnN Name -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    f (L SrcSpanAnnN
    _ Name
    name)
              = do { Kind
    sigma_ty <- UserTypeCtxt -> LHsSigWcType GhcRn -> TcM Kind
    tcHsSigWcType (Name -> Bool -> UserTypeCtxt
    FunSigCtxt Name
    name Bool
    False) LHsSigWcType GhcRn
    hs_ty
                   ; TcId -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Name -> Kind -> TcId
    mkVanillaGlobal Name
    name Kind
    sigma_ty) }
            -- Notice that we make GlobalIds, not LocalIds
        tc_boot_sig Sig GhcRn
    s = String -> SDoc -> TcM [TcId]
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "tcHsBootSigs/tc_boot_sig" (Sig GhcRn -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Sig GhcRn
    s)

    badBootDeclErr :: SDoc
    badBootDeclErr :: SDoc
    badBootDeclErr = String -> SDoc
    text String
    "Illegal declarations in an hs-boot file"

    ------------------------
    tcLocalBinds :: HsLocalBinds GhcRn -> TcM thing
                 -> TcM (HsLocalBinds GhcTc, thing)

    tcLocalBinds :: forall thing.
    HsLocalBinds GhcRn -> TcM thing -> TcM (HsLocalBinds GhcTc, thing)
    tcLocalBinds (EmptyLocalBinds XEmptyLocalBinds GhcRn GhcRn
    x) TcM thing
    thing_inside
      = do  { thing
    thing <- TcM thing
    thing_inside
            ; (HsLocalBinds GhcTc, thing) -> TcM (HsLocalBinds GhcTc, thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (XEmptyLocalBinds GhcTc GhcTc -> HsLocalBinds GhcTc
    forall idL idR. XEmptyLocalBinds idL idR -> HsLocalBindsLR idL idR
    EmptyLocalBinds XEmptyLocalBinds GhcRn GhcRn
    XEmptyLocalBinds GhcTc GhcTc
    x, thing
    thing) }

    tcLocalBinds (HsValBinds XHsValBinds GhcRn GhcRn
    x (XValBindsLR (NValBinds [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs))) TcM thing
    thing_inside
      = do  { ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    binds', thing
    thing) <- TopLevelFlag
    -> [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    forall thing.
    TopLevelFlag
    -> [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcValBinds TopLevelFlag
    NotTopLevel [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs TcM thing
    thing_inside
            ; (HsLocalBinds GhcTc, thing) -> TcM (HsLocalBinds GhcTc, thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (XHsValBinds GhcTc GhcTc
    -> HsValBindsLR GhcTc GhcTc -> HsLocalBinds GhcTc
    forall idL idR.
    XHsValBinds idL idR
    -> HsValBindsLR idL idR -> HsLocalBindsLR idL idR
    HsValBinds XHsValBinds GhcRn GhcRn
    XHsValBinds GhcTc GhcTc
    x (XXValBindsLR GhcTc GhcTc -> HsValBindsLR GhcTc GhcTc
    forall idL idR. XXValBindsLR idL idR -> HsValBindsLR idL idR
    XValBindsLR ([(RecFlag, LHsBinds GhcTc)] -> [LSig GhcRn] -> NHsValBindsLR GhcTc
    forall idL.
    [(RecFlag, LHsBinds idL)] -> [LSig GhcRn] -> NHsValBindsLR idL
    NValBinds [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    [(RecFlag, LHsBinds GhcTc)]
    binds' [LSig GhcRn]
    sigs)), thing
    thing) }
    tcLocalBinds (HsValBinds XHsValBinds GhcRn GhcRn
    _ (ValBinds {})) TcM thing
    _ = String -> TcM (HsLocalBinds GhcTc, thing)
    forall a. String -> a
    panic String
    "tcLocalBinds"

    tcLocalBinds (HsIPBinds XHsIPBinds GhcRn GhcRn
    x (IPBinds XIPBinds GhcRn
    _ [LIPBind GhcRn]
    ip_binds)) TcM thing
    thing_inside
      = do  { Class
    ipClass <- Name -> TcM Class
    tcLookupClass Name
    ipClassName
            ; ([TcId]
    given_ips, [LocatedA (IPBind GhcTc)]
    ip_binds') <-
                (LocatedA (IPBind GhcRn)
     -> IOEnv (Env TcGblEnv TcLclEnv) (TcId, LocatedA (IPBind GhcTc)))
    -> [LocatedA (IPBind GhcRn)]
    -> IOEnv
         (Env TcGblEnv TcLclEnv) ([TcId], [LocatedA (IPBind GhcTc)])
    forall (m :: * -> *) a b c.
    Applicative m =>
    (a -> m (b, c)) -> [a] -> m ([b], [c])
    mapAndUnzipM ((IPBind GhcRn -> TcM (TcId, IPBind GhcTc))
    -> LocatedA (IPBind GhcRn)
    -> IOEnv (Env TcGblEnv TcLclEnv) (TcId, LocatedA (IPBind GhcTc))
    forall a b c.
    (a -> TcM (b, c)) -> LocatedA a -> TcM (b, LocatedA c)
    wrapLocSndMA (Class -> IPBind GhcRn -> TcM (TcId, IPBind GhcTc)
    tc_ip_bind Class
    ipClass)) [LocatedA (IPBind GhcRn)]
    [LIPBind GhcRn]
    ip_binds

            -- If the binding binds ?x = E, we  must now
            -- discharge any ?x constraints in expr_lie
            -- See Note [Implicit parameter untouchables]
            ; (TcEvBinds
    ev_binds, thing
    result) <- SkolemInfo
    -> [TcId] -> [TcId] -> TcM thing -> TcM (TcEvBinds, thing)
    forall result.
    SkolemInfo
    -> [TcId] -> [TcId] -> TcM result -> TcM (TcEvBinds, result)
    checkConstraints ([HsIPName] -> SkolemInfo
    IPSkol [HsIPName]
    ips)
                                      [] [TcId]
    given_ips TcM thing
    thing_inside

            ; (HsLocalBinds GhcTc, thing) -> TcM (HsLocalBinds GhcTc, thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (XHsIPBinds GhcTc GhcTc -> HsIPBinds GhcTc -> HsLocalBinds GhcTc
    forall idL idR.
    XHsIPBinds idL idR -> HsIPBinds idR -> HsLocalBindsLR idL idR
    HsIPBinds XHsIPBinds GhcRn GhcRn
    XHsIPBinds GhcTc GhcTc
    x (XIPBinds GhcTc -> [LIPBind GhcTc] -> HsIPBinds GhcTc
    forall id. XIPBinds id -> [LIPBind id] -> HsIPBinds id
    IPBinds XIPBinds GhcTc
    TcEvBinds
    ev_binds [LocatedA (IPBind GhcTc)]
    [LIPBind GhcTc]
    ip_binds') , thing
    result) }
      where
        ips :: [HsIPName]
    ips = [HsIPName
    ip | (L SrcSpanAnnA
    _ (IPBind XCIPBind GhcRn
    _ (Left (L SrcSpan
    _ HsIPName
    ip)) LHsExpr GhcRn
    _)) <- [LocatedA (IPBind GhcRn)]
    [LIPBind GhcRn]
    ip_binds]

            -- I wonder if we should do these one at a time
            -- Consider     ?x = 4
            --              ?y = ?x + 1
        tc_ip_bind :: Class -> IPBind GhcRn -> TcM (TcId, IPBind GhcTc)
    tc_ip_bind Class
    ipClass (IPBind XCIPBind GhcRn
    _ (Left (L SrcSpan
    _ HsIPName
    ip)) LHsExpr GhcRn
    expr)
           = do { Kind
    ty <- TcM Kind
    newOpenFlexiTyVarTy
                ; let p :: Kind
    p = FastString -> Kind
    mkStrLitTy (FastString -> Kind) -> FastString -> Kind
    forall a b. (a -> b) -> a -> b
    $ HsIPName -> FastString
    hsIPNameFS HsIPName
    ip
                ; TcId
    ip_id <- Class -> TcThetaType -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newDict Class
    ipClass [ Kind
    p, Kind
    ty ]
                ; GenLocated SrcSpanAnnA (HsExpr GhcTc)
    expr' <- LHsExpr GhcRn -> Kind -> TcM (LHsExpr GhcTc)
    tcCheckMonoExpr LHsExpr GhcRn
    expr Kind
    ty
                ; let d :: GenLocated SrcSpanAnnA (HsExpr GhcTc)
    d = Class -> Kind -> Kind -> HsExpr GhcTc -> HsExpr GhcTc
    toDict Class
    ipClass Kind
    p Kind
    ty (HsExpr GhcTc -> HsExpr GhcTc)
    -> GenLocated SrcSpanAnnA (HsExpr GhcTc)
    -> GenLocated SrcSpanAnnA (HsExpr GhcTc)
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    `fmap` GenLocated SrcSpanAnnA (HsExpr GhcTc)
    expr'
                ; (TcId, IPBind GhcTc) -> TcM (TcId, IPBind GhcTc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TcId
    ip_id, (XCIPBind GhcTc
    -> Either (XRec GhcTc HsIPName) (IdP GhcTc)
    -> LHsExpr GhcTc
    -> IPBind GhcTc
    forall id.
    XCIPBind id
    -> Either (XRec id HsIPName) (IdP id) -> LHsExpr id -> IPBind id
    IPBind XCIPBind GhcTc
    forall a. EpAnn a
    noAnn (TcId -> Either (XRec GhcTc HsIPName) TcId
    forall a b. b -> Either a b
    Right TcId
    ip_id) GenLocated SrcSpanAnnA (HsExpr GhcTc)
    LHsExpr GhcTc
    d)) }
        tc_ip_bind Class
    _ (IPBind XCIPBind GhcRn
    _ (Right {}) LHsExpr GhcRn
    _) = String -> TcM (TcId, IPBind GhcTc)
    forall a. String -> a
    panic String
    "tc_ip_bind"

        -- Coerces a `t` into a dictionary for `IP "x" t`.
        -- co : t -> IP "x" t
        toDict :: Class -> Kind -> Kind -> HsExpr GhcTc -> HsExpr GhcTc
    toDict Class
    ipClass Kind
    x Kind
    ty = HsWrapper -> HsExpr GhcTc -> HsExpr GhcTc
    mkHsWrap (HsWrapper -> HsExpr GhcTc -> HsExpr GhcTc)
    -> HsWrapper -> HsExpr GhcTc -> HsExpr GhcTc
    forall a b. (a -> b) -> a -> b
    $ TcCoercionR -> HsWrapper
    mkWpCastR (TcCoercionR -> HsWrapper) -> TcCoercionR -> HsWrapper
    forall a b. (a -> b) -> a -> b
    $
                              Kind -> TcCoercionR
    wrapIP (Kind -> TcCoercionR) -> Kind -> TcCoercionR
    forall a b. (a -> b) -> a -> b
    $ Class -> TcThetaType -> Kind
    mkClassPred Class
    ipClass [Kind
    x,Kind
    ty]

    {- Note [Implicit parameter untouchables]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    We add the type variables in the types of the implicit parameters
    as untouchables, not so much because we really must not unify them,
    but rather because we otherwise end up with constraints like this
        Num alpha, Implic { wanted = alpha ~ Int }
    The constraint solver solves alpha~Int by unification, but then
    doesn't float that solved constraint out (it's not an unsolved
    wanted).  Result disaster: the (Num alpha) is again solved, this
    time by defaulting.  No no no.

    However [Oct 10] this is all handled automatically by the
    untouchable-range idea.
    -}

    tcValBinds :: TopLevelFlag
               -> [(RecFlag, LHsBinds GhcRn)] -> [LSig GhcRn]
               -> TcM thing
               -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)

    tcValBinds :: forall thing.
    TopLevelFlag
    -> [(RecFlag, LHsBinds GhcRn)]
    -> [LSig GhcRn]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcValBinds TopLevelFlag
    top_lvl [(RecFlag, LHsBinds GhcRn)]
    binds [LSig GhcRn]
    sigs TcM thing
    thing_inside
      = do  {   -- Typecheck the signatures
                -- It's easier to do so now, once for all the SCCs together
                -- because a single signature  f,g :: <type>
                -- might relate to more than one SCC
              ([TcId]
    poly_ids, TcSigFun
    sig_fn) <- [PatSynBind GhcRn GhcRn]
    -> TcM ([TcId], TcSigFun) -> TcM ([TcId], TcSigFun)
    forall a. [PatSynBind GhcRn GhcRn] -> TcM a -> TcM a
    tcAddPatSynPlaceholders [PatSynBind GhcRn GhcRn]
    patsyns (TcM ([TcId], TcSigFun) -> TcM ([TcId], TcSigFun))
    -> TcM ([TcId], TcSigFun) -> TcM ([TcId], TcSigFun)
    forall a b. (a -> b) -> a -> b
    $
                                    [LSig GhcRn] -> TcM ([TcId], TcSigFun)
    tcTySigs [LSig GhcRn]
    sigs

            -- Extend the envt right away with all the Ids
            --   declared with complete type signatures
            -- Do not extend the TcBinderStack; instead
            --   we extend it on a per-rhs basis in tcExtendForRhs
            --   See Note [Relevant bindings and the binder stack]
            --
            -- For the moment, let bindings and top-level bindings introduce
            -- only unrestricted variables.
            ; TopLevelFlag
    -> [TcId]
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall a. TopLevelFlag -> [TcId] -> TcM a -> TcM a
    tcExtendSigIds TopLevelFlag
    top_lvl [TcId]
    poly_ids (TcM
       ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
        thing)
     -> TcM
          ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
           thing))
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall a b. (a -> b) -> a -> b
    $
         do { ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    binds', ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    extra_binds', thing
    thing))
                  <- TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> [(RecFlag, LHsBinds GhcRn)]
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, LHsBinds GhcTc)],
          ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
           thing))
    forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> [(RecFlag, LHsBinds GhcRn)]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcBindGroups TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn [(RecFlag, LHsBinds GhcRn)]
    binds (TcM
       ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
        thing)
     -> TcM
          ([(RecFlag, LHsBinds GhcTc)],
           ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
            thing)))
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, LHsBinds GhcTc)],
          ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
           thing))
    forall a b. (a -> b) -> a -> b
    $
                     do { thing
    thing <- TcM thing
    thing_inside
                           -- See Note [Pattern synonym builders don't yield dependencies]
                           --     in GHC.Rename.Bind
                        ; [Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))]
    patsyn_builders <- (PatSynBind GhcRn GhcRn
     -> IOEnv
          (Env TcGblEnv TcLclEnv)
          (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))))
    -> [PatSynBind GhcRn GhcRn]
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         [Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM (TcPragEnv -> PatSynBind GhcRn GhcRn -> TcM (LHsBinds GhcTc)
    tcPatSynBuilderBind TcPragEnv
    prag_fn) [PatSynBind GhcRn GhcRn]
    patsyns
                        ; let extra_binds :: [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    extra_binds = [ (RecFlag
    NonRecursive, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    builder)
                                            | Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    builder <- [Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))]
    patsyn_builders ]
                        ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    extra_binds, thing
    thing) }
            ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> TcM
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    binds' [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    forall a. [a] -> [a] -> [a]
    ++ [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    extra_binds', thing
    thing) }}
      where
        patsyns :: [PatSynBind GhcRn GhcRn]
    patsyns = [(RecFlag, LHsBinds GhcRn)] -> [PatSynBind GhcRn GhcRn]
    forall id.
    UnXRec id =>
    [(RecFlag, LHsBinds id)] -> [PatSynBind id id]
    getPatSynBinds [(RecFlag, LHsBinds GhcRn)]
    binds
        prag_fn :: TcPragEnv
    prag_fn = [LSig GhcRn] -> LHsBinds GhcRn -> TcPragEnv
    mkPragEnv [LSig GhcRn]
    sigs (((RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall a. Bag a -> Bag a -> Bag a
    unionBags (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> ((RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
        -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> (RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . (RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall a b. (a, b) -> b
    snd) Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall a. Bag a
    emptyBag [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))]
    [(RecFlag, LHsBinds GhcRn)]
    binds)

    ------------------------
    tcBindGroups :: TopLevelFlag -> TcSigFun -> TcPragEnv
                 -> [(RecFlag, LHsBinds GhcRn)] -> TcM thing
                 -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    -- Typecheck a whole lot of value bindings,
    -- one strongly-connected component at a time
    -- Here a "strongly connected component" has the straightforward
    -- meaning of a group of bindings that mention each other,
    -- ignoring type signatures (that part comes later)

    tcBindGroups :: forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> [(RecFlag, LHsBinds GhcRn)]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcBindGroups TopLevelFlag
    _ TcSigFun
    _ TcPragEnv
    _ [] TcM thing
    thing_inside
      = do  { thing
    thing <- TcM thing
    thing_inside
            ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([], thing
    thing) }

    tcBindGroups TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn ((RecFlag, LHsBinds GhcRn)
    group : [(RecFlag, LHsBinds GhcRn)]
    groups) TcM thing
    thing_inside
      = do  { -- See Note [Closed binder groups]
              TcTypeEnv
    type_env <- TcM TcTypeEnv
    getLclTypeEnv
            ; let closed :: IsGroupClosed
    closed = TcTypeEnv -> LHsBinds GhcRn -> IsGroupClosed
    isClosedBndrGroup TcTypeEnv
    type_env ((RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall a b. (a, b) -> b
    snd (RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)))
    (RecFlag, LHsBinds GhcRn)
    group)
            ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    group', ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    groups', thing
    thing))
                    <- TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> (RecFlag, LHsBinds GhcRn)
    -> IsGroupClosed
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, LHsBinds GhcTc)],
          ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
           thing))
    forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> (RecFlag, LHsBinds GhcRn)
    -> IsGroupClosed
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tc_group TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn (RecFlag, LHsBinds GhcRn)
    group IsGroupClosed
    closed (IOEnv
       (Env TcGblEnv TcLclEnv)
       ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
        thing)
     -> TcM
          ([(RecFlag, LHsBinds GhcTc)],
           ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
            thing)))
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    -> TcM
         ([(RecFlag, LHsBinds GhcTc)],
          ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
           thing))
    forall a b. (a -> b) -> a -> b
    $
                       TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> [(RecFlag, LHsBinds GhcRn)]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> [(RecFlag, LHsBinds GhcRn)]
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tcBindGroups TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn [(RecFlag, LHsBinds GhcRn)]
    groups TcM thing
    thing_inside
            ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    group' [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    -> [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    forall a. [a] -> [a] -> [a]
    ++ [(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))]
    groups', thing
    thing) }

    -- Note [Closed binder groups]
    -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~
    --
    --  A mutually recursive group is "closed" if all of the free variables of
    --  the bindings are closed. For example
    --
    -- >  h = \x -> let f = ...g...
    -- >                g = ....f...x...
    -- >             in ...
    --
    -- Here @g@ is not closed because it mentions @x@; and hence neither is @f@
    -- closed.
    --
    -- So we need to compute closed-ness on each strongly connected components,
    -- before we sub-divide it based on what type signatures it has.
    --

    ------------------------
    tc_group :: forall thing.
                TopLevelFlag -> TcSigFun -> TcPragEnv
             -> (RecFlag, LHsBinds GhcRn) -> IsGroupClosed -> TcM thing
             -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)

    -- Typecheck one strongly-connected component of the original program.
    -- We get a list of groups back, because there may
    -- be specialisations etc as well

    tc_group :: forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> (RecFlag, LHsBinds GhcRn)
    -> IsGroupClosed
    -> TcM thing
    -> TcM ([(RecFlag, LHsBinds GhcTc)], thing)
    tc_group TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn (RecFlag
    NonRecursive, LHsBinds GhcRn
    binds) IsGroupClosed
    closed TcM thing
    thing_inside
            -- A single non-recursive binding
            -- We want to keep non-recursive things non-recursive
            -- so that we desugar unlifted bindings correctly
      = do { let bind :: GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind = case Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    forall a. Bag a -> [a]
    bagToList Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    LHsBinds GhcRn
    binds of
                     [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind] -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind
                     []     -> String -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    forall a. String -> a
    panic String
    "tc_group: empty list of binds"
                     [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    _      -> String -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    forall a. String -> a
    panic String
    "tc_group: NonRecursive binds is not a singleton bag"
           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    bind', thing
    thing) <- TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> LHsBind GhcRn
    -> IsGroupClosed
    -> TcM thing
    -> TcM (LHsBinds GhcTc, thing)
    forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> LHsBind GhcRn
    -> IsGroupClosed
    -> TcM thing
    -> TcM (LHsBinds GhcTc, thing)
    tc_single TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    LHsBind GhcRn
    bind IsGroupClosed
    closed
                                         TcM thing
    thing_inside
           ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ( [(RecFlag
    NonRecursive, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    bind')], thing
    thing) }

    tc_group TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn (RecFlag
    Recursive, LHsBinds GhcRn
    binds) IsGroupClosed
    closed TcM thing
    thing_inside
      =     -- To maximise polymorphism, we do a new
            -- strongly-connected-component analysis, this time omitting
            -- any references to variables with type signatures.
            -- (This used to be optional, but isn't now.)
            -- See Note [Polymorphic recursion] in "GHC.Hs.Binds".
        do  { String -> SDoc -> TcRn ()
    traceTc String
    "tc_group rec" (LHsBinds GhcRn -> SDoc
    forall (idL :: Pass) (idR :: Pass).
    (OutputableBndrId idL, OutputableBndrId idR) =>
    LHsBindsLR (GhcPass idL) (GhcPass idR) -> SDoc
    pprLHsBinds LHsBinds GhcRn
    binds)
            ; Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> TcRn ())
    -> TcRn ()
    forall (m :: * -> *) a. Monad m => Maybe a -> (a -> m ()) -> m ()
    whenIsJust Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    mbFirstPatSyn ((GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> TcRn ())
     -> TcRn ())
    -> (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> TcRn ())
    -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $ \GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    lpat_syn ->
                SrcSpan -> LHsBinds GhcRn -> TcRn ()
    forall (p :: Pass) a.
    (OutputableBndrId p, CollectPass (GhcPass p)) =>
    SrcSpan -> LHsBinds (GhcPass p) -> TcM a
    recursivePatSynErr (SrcSpanAnnA -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA (SrcSpanAnnA -> SrcSpan) -> SrcSpanAnnA -> SrcSpan
    forall a b. (a -> b) -> a -> b
    $ GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> SrcSpanAnnA
    forall l e. GenLocated l e -> l
    getLoc GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    lpat_syn) LHsBinds GhcRn
    binds
            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1, thing
    thing) <- [SCC (LHsBind GhcRn)] -> TcM (LHsBinds GhcTc, thing)
    go [SCC (LHsBind GhcRn)]
    sccs
            ; ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
     thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         ([(RecFlag, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))],
          thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([(RecFlag
    Recursive, Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1)], thing
    thing) }
                    -- Rec them all together
      where
        mbFirstPatSyn :: Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    mbFirstPatSyn = (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> Bool)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Maybe a
    find (HsBindLR GhcRn GhcRn -> Bool
    forall {idL} {idR}. HsBindLR idL idR -> Bool
    isPatSyn (HsBindLR GhcRn GhcRn -> Bool)
    -> (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
        -> HsBindLR GhcRn GhcRn)
    -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> HsBindLR GhcRn GhcRn
    forall l e. GenLocated l e -> e
    unLoc) Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    LHsBinds GhcRn
    binds
        isPatSyn :: HsBindLR idL idR -> Bool
    isPatSyn PatSynBind{} = Bool
    True
        isPatSyn HsBindLR idL idR
    _ = Bool
    False

        sccs :: [SCC (LHsBind GhcRn)]
        sccs :: [SCC (LHsBind GhcRn)]
    sccs = [Node BKey (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))]
    -> [SCC (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))]
    forall key payload.
    Uniquable key =>
    [Node key payload] -> [SCC payload]
    stronglyConnCompFromEdgedVerticesUniq (TcSigFun -> LHsBinds GhcRn -> [Node BKey (LHsBind GhcRn)]
    mkEdges TcSigFun
    sig_fn LHsBinds GhcRn
    binds)

        go :: [SCC (LHsBind GhcRn)] -> TcM (LHsBinds GhcTc, thing)
        go :: [SCC (LHsBind GhcRn)] -> TcM (LHsBinds GhcTc, thing)
    go (SCC (LHsBind GhcRn)
    scc:[SCC (LHsBind GhcRn)]
    sccs) = do  { (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1, [TcId]
    ids1) <- SCC (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> TcM (LHsBinds GhcTc, [TcId])
    tc_scc SCC (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    SCC (LHsBind GhcRn)
    scc
                             -- recursive bindings must be unrestricted
                             -- (the ids added to the environment here are the name of the recursive definitions).
                            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds2, thing
    thing) <- TopLevelFlag
    -> TcSigFun
    -> IsGroupClosed
    -> [TcId]
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    forall a.
    TopLevelFlag
    -> TcSigFun -> IsGroupClosed -> [TcId] -> TcM a -> TcM a
    tcExtendLetEnv TopLevelFlag
    top_lvl TcSigFun
    sig_fn IsGroupClosed
    closed [TcId]
    ids1
                                                                ([SCC (LHsBind GhcRn)] -> TcM (LHsBinds GhcTc, thing)
    go [SCC (LHsBind GhcRn)]
    sccs)
                            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1 Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. Bag a -> Bag a -> Bag a
    `unionBags` Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds2, thing
    thing) }
        go []         = do  { thing
    thing <- TcM thing
    thing_inside; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. Bag a
    emptyBag, thing
    thing) }

        tc_scc :: SCC (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> TcM (LHsBinds GhcTc, [TcId])
    tc_scc (AcyclicSCC GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind) = RecFlag
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> TcM (LHsBinds GhcTc, [TcId])
    tc_sub_group RecFlag
    NonRecursive [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind]
        tc_scc (CyclicSCC [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    binds) = RecFlag
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> TcM (LHsBinds GhcTc, [TcId])
    tc_sub_group RecFlag
    Recursive    [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    binds

        tc_sub_group :: RecFlag
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> TcM (LHsBinds GhcTc, [TcId])
    tc_sub_group RecFlag
    rec_tc [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    binds =
          TcSigFun
    -> TcPragEnv
    -> RecFlag
    -> RecFlag
    -> IsGroupClosed
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyBinds TcSigFun
    sig_fn TcPragEnv
    prag_fn RecFlag
    Recursive RecFlag
    rec_tc IsGroupClosed
    closed [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    [LHsBind GhcRn]
    binds

    recursivePatSynErr ::
         (OutputableBndrId p, CollectPass (GhcPass p))
      => SrcSpan -- ^ The location of the first pattern synonym binding
                 --   (for error reporting)
      -> LHsBinds (GhcPass p)
      -> TcM a
    recursivePatSynErr :: forall (p :: Pass) a.
    (OutputableBndrId p, CollectPass (GhcPass p)) =>
    SrcSpan -> LHsBinds (GhcPass p) -> TcM a
    recursivePatSynErr SrcSpan
    loc LHsBinds (GhcPass p)
    binds
      = SrcSpan -> SDoc -> TcRn a
    forall a. SrcSpan -> SDoc -> TcRn a
    failAt SrcSpan
    loc (SDoc -> TcRn a) -> SDoc -> TcRn a
    forall a b. (a -> b) -> a -> b
    $
        SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "Recursive pattern synonym definition with following bindings:")
           BKey
    2 ([SDoc] -> SDoc
    vcat ([SDoc] -> SDoc) -> [SDoc] -> SDoc
    forall a b. (a -> b) -> a -> b
    $ (GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p)) -> SDoc)
    -> [GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p))]
    -> [SDoc]
    forall a b. (a -> b) -> [a] -> [b]
    map GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p)) -> SDoc
    forall {p} {a} {idR}.
    (Outputable (IdP p), CollectPass p) =>
    GenLocated (SrcSpanAnn' a) (HsBindLR p idR) -> SDoc
    pprLBind ([GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p))]
     -> [SDoc])
    -> (LHsBinds (GhcPass p)
        -> [GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p))])
    -> LHsBinds (GhcPass p)
    -> [SDoc]
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . LHsBinds (GhcPass p)
    -> [GenLocated SrcSpanAnnA (HsBindLR (GhcPass p) (GhcPass p))]
    forall a. Bag a -> [a]
    bagToList (LHsBinds (GhcPass p) -> [SDoc]) -> LHsBinds (GhcPass p) -> [SDoc]
    forall a b. (a -> b) -> a -> b
    $ LHsBinds (GhcPass p)
    binds)
      where
        pprLoc :: a -> SDoc
    pprLoc a
    loc  = SDoc -> SDoc
    parens (String -> SDoc
    text String
    "defined at" SDoc -> SDoc -> SDoc
    <+> a -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr a
    loc)
        pprLBind :: GenLocated (SrcSpanAnn' a) (HsBindLR p idR) -> SDoc
    pprLBind (L SrcSpanAnn' a
    loc HsBindLR p idR
    bind) = (IdP p -> SDoc) -> [IdP p] -> SDoc
    forall a. (a -> SDoc) -> [a] -> SDoc
    pprWithCommas IdP p -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (CollectFlag p -> HsBindLR p idR -> [IdP p]
    forall p idR.
    CollectPass p =>
    CollectFlag p -> HsBindLR p idR -> [IdP p]
    collectHsBindBinders CollectFlag p
    forall p. CollectFlag p
    CollNoDictBinders HsBindLR p idR
    bind)
                                    SDoc -> SDoc -> SDoc
    <+> SrcSpan -> SDoc
    forall a. Outputable a => a -> SDoc
    pprLoc (SrcSpanAnn' a -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA SrcSpanAnn' a
    loc)

    tc_single :: forall thing.
                TopLevelFlag -> TcSigFun -> TcPragEnv
              -> LHsBind GhcRn -> IsGroupClosed -> TcM thing
              -> TcM (LHsBinds GhcTc, thing)
    tc_single :: forall thing.
    TopLevelFlag
    -> TcSigFun
    -> TcPragEnv
    -> LHsBind GhcRn
    -> IsGroupClosed
    -> TcM thing
    -> TcM (LHsBinds GhcTc, thing)
    tc_single TopLevelFlag
    _top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn
              (L SrcSpanAnnA
    _ (PatSynBind XPatSynBind GhcRn GhcRn
    _ psb :: PatSynBind GhcRn GhcRn
    psb@PSB{ psb_id :: forall idL idR. PatSynBind idL idR -> LIdP idL
    psb_id = L SrcSpanAnnN
    _ Name
    name }))
              IsGroupClosed
    _ TcM thing
    thing_inside
      = do { (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    aux_binds, TcGblEnv
    tcg_env) <- PatSynBind GhcRn GhcRn
    -> Maybe TcSigInfo -> TcPragEnv -> TcM (LHsBinds GhcTc, TcGblEnv)
    tcPatSynDecl PatSynBind GhcRn GhcRn
    psb (TcSigFun
    sig_fn Name
    name) TcPragEnv
    prag_fn
           ; thing
    thing <- TcGblEnv -> TcM thing -> TcM thing
    forall gbl lcl a. gbl -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a
    setGblEnv TcGblEnv
    tcg_env TcM thing
    thing_inside
           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    aux_binds, thing
    thing)
           }

    tc_single TopLevelFlag
    top_lvl TcSigFun
    sig_fn TcPragEnv
    prag_fn LHsBind GhcRn
    lbind IsGroupClosed
    closed TcM thing
    thing_inside
      = do { (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1, [TcId]
    ids) <- TcSigFun
    -> TcPragEnv
    -> RecFlag
    -> RecFlag
    -> IsGroupClosed
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyBinds TcSigFun
    sig_fn TcPragEnv
    prag_fn
                                          RecFlag
    NonRecursive RecFlag
    NonRecursive
                                          IsGroupClosed
    closed
                                          [LHsBind GhcRn
    lbind]
             -- since we are defining a non-recursive binding, it is not necessary here
             -- to define an unrestricted binding. But we do so until toplevel linear bindings are supported.
           ; thing
    thing <- TopLevelFlag
    -> TcSigFun -> IsGroupClosed -> [TcId] -> TcM thing -> TcM thing
    forall a.
    TopLevelFlag
    -> TcSigFun -> IsGroupClosed -> [TcId] -> TcM a -> TcM a
    tcExtendLetEnv TopLevelFlag
    top_lvl TcSigFun
    sig_fn IsGroupClosed
    closed [TcId]
    ids TcM thing
    thing_inside
           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), thing)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds1, thing
    thing) }

    ------------------------
    type BKey = Int -- Just number off the bindings

    mkEdges :: TcSigFun -> LHsBinds GhcRn -> [Node BKey (LHsBind GhcRn)]
    -- See Note [Polymorphic recursion] in "GHC.Hs.Binds".
    mkEdges :: TcSigFun -> LHsBinds GhcRn -> [Node BKey (LHsBind GhcRn)]
    mkEdges TcSigFun
    sig_fn LHsBinds GhcRn
    binds
      = [ GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> BKey
    -> [BKey]
    -> Node BKey (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    forall key payload. payload -> key -> [key] -> Node key payload
    DigraphNode GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind BKey
    key [BKey
    key | Name
    n <- UniqSet Name -> [Name]
    forall elt. UniqSet elt -> [elt]
    nonDetEltsUniqSet (HsBindLR GhcRn GhcRn -> XFunBind GhcRn GhcRn
    forall {idL} {idR}.
    (XFunBind idL idR ~ UniqSet Name,
     XPatBind idL idR ~ XFunBind idL idR) =>
    HsBindLR idL idR -> XFunBind idL idR
    bind_fvs (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> HsBindLR GhcRn GhcRn
    forall l e. GenLocated l e -> e
    unLoc GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind)),
                             Just BKey
    key <- [NameEnv BKey -> Name -> Maybe BKey
    forall a. NameEnv a -> Name -> Maybe a
    lookupNameEnv NameEnv BKey
    key_map Name
    n], Name -> Bool
    no_sig Name
    n ]
        | (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind, BKey
    key) <- [(GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), BKey)]
    keyd_binds
        ]
        -- It's OK to use nonDetEltsUFM here as stronglyConnCompFromEdgedVertices
        -- is still deterministic even if the edges are in nondeterministic order
        -- as explained in Note [Deterministic SCC] in GHC.Data.Graph.Directed.
      where
        bind_fvs :: HsBindLR idL idR -> XFunBind idL idR
    bind_fvs (FunBind { fun_ext :: forall idL idR. HsBindLR idL idR -> XFunBind idL idR
    fun_ext = XFunBind idL idR
    fvs }) = XFunBind idL idR
    fvs
        bind_fvs (PatBind { pat_ext :: forall idL idR. HsBindLR idL idR -> XPatBind idL idR
    pat_ext = XPatBind idL idR
    fvs }) = XFunBind idL idR
    XPatBind idL idR
    fvs
        bind_fvs HsBindLR idL idR
    _                           = UniqSet Name
    XFunBind idL idR
    emptyNameSet

        no_sig :: Name -> Bool
        no_sig :: Name -> Bool
    no_sig Name
    n = Bool -> Bool
    not (TcSigFun -> Name -> Bool
    hasCompleteSig TcSigFun
    sig_fn Name
    n)

        keyd_binds :: [(GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), BKey)]
    keyd_binds = Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    forall a. Bag a -> [a]
    bagToList Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    LHsBinds GhcRn
    binds [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> [BKey]
    -> [(GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), BKey)]
    forall a b. [a] -> [b] -> [(a, b)]
    `zip` [BKey
    0::BKey ..]

        key_map :: NameEnv BKey     -- Which binding it comes from
        key_map :: NameEnv BKey
    key_map = [(Name, BKey)] -> NameEnv BKey
    forall a. [(Name, a)] -> NameEnv a
    mkNameEnv [(Name
    bndr, BKey
    key) | (L SrcSpanAnnA
    _ HsBindLR GhcRn GhcRn
    bind, BKey
    key) <- [(GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), BKey)]
    keyd_binds
                                         , Name
    bndr <- CollectFlag GhcRn -> HsBindLR GhcRn GhcRn -> [IdP GhcRn]
    forall p idR.
    CollectPass p =>
    CollectFlag p -> HsBindLR p idR -> [IdP p]
    collectHsBindBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders HsBindLR GhcRn GhcRn
    bind ]

    ------------------------
    tcPolyBinds :: TcSigFun -> TcPragEnv
                -> RecFlag         -- Whether the group is really recursive
                -> RecFlag         -- Whether it's recursive after breaking
                                   -- dependencies based on type signatures
                -> IsGroupClosed   -- Whether the group is closed
                -> [LHsBind GhcRn]  -- None are PatSynBind
                -> TcM (LHsBinds GhcTc, [TcId])

    -- Typechecks a single bunch of values bindings all together,
    -- and generalises them.  The bunch may be only part of a recursive
    -- group, because we use type signatures to maximise polymorphism
    --
    -- Returns a list because the input may be a single non-recursive binding,
    -- in which case the dependency order of the resulting bindings is
    -- important.
    --
    -- Knows nothing about the scope of the bindings
    -- None of the bindings are pattern synonyms

    tcPolyBinds :: TcSigFun
    -> TcPragEnv
    -> RecFlag
    -> RecFlag
    -> IsGroupClosed
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyBinds TcSigFun
    sig_fn TcPragEnv
    prag_fn RecFlag
    rec_group RecFlag
    rec_tc IsGroupClosed
    closed [LHsBind GhcRn]
    bind_list
      = SrcSpan
    -> TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId])
    forall a. SrcSpan -> TcRn a -> TcRn a
    setSrcSpan SrcSpan
    loc                              (TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId]))
    -> TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId])
    forall a b. (a -> b) -> a -> b
    $
        TcM (LHsBinds GhcTc, [TcId])
    -> TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId])
    forall r. TcRn r -> TcRn r -> TcRn r
    recoverM ([Name] -> TcSigFun -> TcM (LHsBinds GhcTc, [TcId])
    recoveryCode [Name]
    [IdP GhcRn]
    binder_names TcSigFun
    sig_fn) (TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId]))
    -> TcM (LHsBinds GhcTc, [TcId]) -> TcM (LHsBinds GhcTc, [TcId])
    forall a b. (a -> b) -> a -> b
    $ do
            -- Set up main recover; take advantage of any type sigs

        { String -> SDoc -> TcRn ()
    traceTc String
    "------------------------------------------------" SDoc
    Outputable.empty
        ; String -> SDoc -> TcRn ()
    traceTc String
    "Bindings for {" ([Name] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [Name]
    [IdP GhcRn]
    binder_names)
        ; DynFlags
    dflags   <- IOEnv (Env TcGblEnv TcLclEnv) DynFlags
    forall (m :: * -> *). HasDynFlags m => m DynFlags
    getDynFlags
        ; let plan :: GeneralisationPlan
    plan = DynFlags
    -> [LHsBind GhcRn]
    -> IsGroupClosed
    -> TcSigFun
    -> GeneralisationPlan
    decideGeneralisationPlan DynFlags
    dflags [LHsBind GhcRn]
    bind_list IsGroupClosed
    closed TcSigFun
    sig_fn
        ; String -> SDoc -> TcRn ()
    traceTc String
    "Generalisation plan" (GeneralisationPlan -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GeneralisationPlan
    plan)
        ; result :: (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    result@(Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    _, [TcId]
    poly_ids) <- case GeneralisationPlan
    plan of
             GeneralisationPlan
    NoGen              -> RecFlag
    -> TcPragEnv
    -> TcSigFun
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyNoGen RecFlag
    rec_tc TcPragEnv
    prag_fn TcSigFun
    sig_fn [LHsBind GhcRn]
    bind_list
             InferGen Bool
    mn        -> RecFlag
    -> TcPragEnv
    -> TcSigFun
    -> Bool
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyInfer RecFlag
    rec_tc TcPragEnv
    prag_fn TcSigFun
    sig_fn Bool
    mn [LHsBind GhcRn]
    bind_list
             CheckGen LHsBind GhcRn
    lbind TcIdSigInfo
    sig -> TcPragEnv
    -> TcIdSigInfo -> LHsBind GhcRn -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyCheck TcPragEnv
    prag_fn TcIdSigInfo
    sig LHsBind GhcRn
    lbind

        ; String -> SDoc -> TcRn ()
    traceTc String
    "} End of bindings for" ([SDoc] -> SDoc
    vcat [ [Name] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [Name]
    [IdP GhcRn]
    binder_names, RecFlag -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr RecFlag
    rec_group
                                                , [SDoc] -> SDoc
    vcat [TcId -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcId
    id SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (TcId -> Kind
    idType TcId
    id) | TcId
    id <- [TcId]
    poly_ids]
                                              ])

        ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    result }
      where
        binder_names :: [IdP GhcRn]
    binder_names = CollectFlag GhcRn -> [LHsBind GhcRn] -> [IdP GhcRn]
    forall p idR.
    CollectPass p =>
    CollectFlag p -> [LHsBindLR p idR] -> [IdP p]
    collectHsBindListBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders [LHsBind GhcRn]
    bind_list
        loc :: SrcSpan
    loc = (SrcSpan -> SrcSpan -> SrcSpan) -> [SrcSpan] -> SrcSpan
    forall (t :: * -> *) a. Foldable t => (a -> a -> a) -> t a -> a
    foldr1 SrcSpan -> SrcSpan -> SrcSpan
    combineSrcSpans ((GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> SrcSpan)
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)] -> [SrcSpan]
    forall a b. (a -> b) -> [a] -> [b]
    map (SrcSpanAnnA -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA (SrcSpanAnnA -> SrcSpan)
    -> (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> SrcSpanAnnA)
    -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> SrcSpan
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> SrcSpanAnnA
    forall l e. GenLocated l e -> l
    getLoc) [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    [LHsBind GhcRn]
    bind_list)
             -- The mbinds have been dependency analysed and
             -- may no longer be adjacent; so find the narrowest
             -- span that includes them all

    --------------
    -- If typechecking the binds fails, then return with each
    -- signature-less binder given type (forall a.a), to minimise
    -- subsequent error messages
    recoveryCode :: [Name] -> TcSigFun -> TcM (LHsBinds GhcTc, [Id])
    recoveryCode :: [Name] -> TcSigFun -> TcM (LHsBinds GhcTc, [TcId])
    recoveryCode [Name]
    binder_names TcSigFun
    sig_fn
      = do  { String -> SDoc -> TcRn ()
    traceTc String
    "tcBindsWithSigs: error recovery" ([Name] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [Name]
    binder_names)
            ; let poly_ids :: [TcId]
    poly_ids = (Name -> TcId) -> [Name] -> [TcId]
    forall a b. (a -> b) -> [a] -> [b]
    map Name -> TcId
    mk_dummy [Name]
    binder_names
            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. Bag a
    emptyBag, [TcId]
    poly_ids) }
      where
        mk_dummy :: Name -> TcId
    mk_dummy Name
    name
          | Just TcSigInfo
    sig <- TcSigFun
    sig_fn Name
    name
          , Just TcId
    poly_id <- TcSigInfo -> Maybe TcId
    completeSigPolyId_maybe TcSigInfo
    sig
          = TcId
    poly_id
          | Bool
    otherwise
          = HasDebugCallStack => Name -> Kind -> Kind -> TcId
    Name -> Kind -> Kind -> TcId
    mkLocalId Name
    name Kind
    Many Kind
    forall_a_a

    forall_a_a :: TcType
    -- At one point I had (forall r (a :: TYPE r). a), but of course
    -- that type is ill-formed: its mentions 'r' which escapes r's scope.
    -- Another alternative would be (forall (a :: TYPE kappa). a), where
    -- kappa is a unification variable. But I don't think we need that
    -- complication here. I'm going to just use (forall (a::*). a).
    -- See #15276
    forall_a_a :: Kind
    forall_a_a = [TcId] -> Kind -> Kind
    mkSpecForAllTys [TcId
    alphaTyVar] Kind
    alphaTy

    {- *********************************************************************
    *                                                                      *
                             tcPolyNoGen
    *                                                                      *
    ********************************************************************* -}

    tcPolyNoGen     -- No generalisation whatsoever
      :: RecFlag       -- Whether it's recursive after breaking
                       -- dependencies based on type signatures
      -> TcPragEnv -> TcSigFun
      -> [LHsBind GhcRn]
      -> TcM (LHsBinds GhcTc, [TcId])

    tcPolyNoGen :: RecFlag
    -> TcPragEnv
    -> TcSigFun
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyNoGen RecFlag
    rec_tc TcPragEnv
    prag_fn TcSigFun
    tc_sig_fn [LHsBind GhcRn]
    bind_list
      = do { (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds', [MonoBindInfo]
    mono_infos) <- RecFlag
    -> TcSigFun
    -> LetBndrSpec
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    tcMonoBinds RecFlag
    rec_tc TcSigFun
    tc_sig_fn
                                                 (TcPragEnv -> LetBndrSpec
    LetGblBndr TcPragEnv
    prag_fn)
                                                 [LHsBind GhcRn]
    bind_list
           ; [TcId]
    mono_ids' <- (MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) TcId)
    -> [MonoBindInfo] -> TcM [TcId]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    tc_mono_info [MonoBindInfo]
    mono_infos
           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds', [TcId]
    mono_ids') }
      where
        tc_mono_info :: MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    tc_mono_info (MBI { mbi_poly_name :: MonoBindInfo -> Name
    mbi_poly_name = Name
    name, mbi_mono_id :: MonoBindInfo -> TcId
    mbi_mono_id = TcId
    mono_id })
          = do { [LTcSpecPrag]
    _specs <- TcId -> [LSig GhcRn] -> TcM [LTcSpecPrag]
    tcSpecPrags TcId
    mono_id (TcPragEnv -> Name -> [LSig GhcRn]
    lookupPragEnv TcPragEnv
    prag_fn Name
    name)
               ; TcId -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall (m :: * -> *) a. Monad m => a -> m a
    return TcId
    mono_id }
               -- NB: tcPrags generates error messages for
               --     specialisation pragmas for non-overloaded sigs
               -- Indeed that is why we call it here!
               -- So we can safely ignore _specs

    {- *********************************************************************
    *                                                                      *
                             tcPolyCheck
    *                                                                      *
    ********************************************************************* -}

    tcPolyCheck :: TcPragEnv
                -> TcIdSigInfo     -- Must be a complete signature
                -> LHsBind GhcRn   -- Must be a FunBind
                -> TcM (LHsBinds GhcTc, [TcId])
    -- There is just one binding,
    --   it is a FunBind
    --   it has a complete type signature,
    tcPolyCheck :: TcPragEnv
    -> TcIdSigInfo -> LHsBind GhcRn -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyCheck TcPragEnv
    prag_fn
                (CompleteSig { sig_bndr :: TcIdSigInfo -> TcId
    sig_bndr  = TcId
    poly_id
                             , sig_ctxt :: TcIdSigInfo -> UserTypeCtxt
    sig_ctxt  = UserTypeCtxt
    ctxt
                             , sig_loc :: TcIdSigInfo -> SrcSpan
    sig_loc   = SrcSpan
    sig_loc })
                (L SrcSpanAnnA
    bind_loc (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = L SrcSpanAnnN
    nm_loc Name
    name
                                     , fun_matches :: forall idL idR. HsBindLR idL idR -> MatchGroup idR (LHsExpr idR)
    fun_matches = MatchGroup GhcRn (LHsExpr GhcRn)
    matches }))
      = do { String -> SDoc -> TcRn ()
    traceTc String
    "tcPolyCheck" (TcId -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcId
    poly_id SDoc -> SDoc -> SDoc
    $$ SrcSpan -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr SrcSpan
    sig_loc)

           ; Name
    mono_name <- OccName -> SrcSpan -> TcM Name
    newNameAt (Name -> OccName
    nameOccName Name
    name) (SrcSpanAnnN -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA SrcSpanAnnN
    nm_loc)
           ; (HsWrapper
    wrap_gen, (HsWrapper
    wrap_res, MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    matches'))
                 <- SrcSpan
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    forall a. SrcSpan -> TcRn a -> TcRn a
    setSrcSpan SrcSpan
    sig_loc (TcRn
       (HsWrapper,
        (HsWrapper,
         MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
     -> TcRn
          (HsWrapper,
           (HsWrapper,
            MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))))
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    forall a b. (a -> b) -> a -> b
    $ -- Sets the binding location for the skolems
                    UserTypeCtxt
    -> Kind
    -> (Kind
        -> TcM
             (HsWrapper,
              MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    forall result.
    UserTypeCtxt
    -> Kind -> (Kind -> TcM result) -> TcM (HsWrapper, result)
    tcSkolemiseScoped UserTypeCtxt
    ctxt (TcId -> Kind
    idType TcId
    poly_id) ((Kind
      -> TcM
           (HsWrapper,
            MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
     -> TcRn
          (HsWrapper,
           (HsWrapper,
            MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))))
    -> (Kind
        -> TcM
             (HsWrapper,
              MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcRn
         (HsWrapper,
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    forall a b. (a -> b) -> a -> b
    $ \Kind
    rho_ty ->
                    -- Unwraps multiple layers; e.g
                    --    f :: forall a. Eq a => forall b. Ord b => blah
                    -- NB: tcSkolemise makes fresh type variables
                    -- See Note [Instantiate sig with fresh variables]

                    let mono_id :: TcId
    mono_id = HasDebugCallStack => Name -> Kind -> Kind -> TcId
    Name -> Kind -> Kind -> TcId
    mkLocalId Name
    mono_name (TcId -> Kind
    varMult TcId
    poly_id) Kind
    rho_ty in
                    [TcBinder]
    -> TcM
         (HsWrapper,
          MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))
    -> TcM
         (HsWrapper,
          MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))
    forall a. [TcBinder] -> TcM a -> TcM a
    tcExtendBinderStack [TcId -> TopLevelFlag -> TcBinder
    TcIdBndr TcId
    mono_id TopLevelFlag
    NotTopLevel] (TcM
       (HsWrapper,
        MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))
     -> TcM
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcM
         (HsWrapper,
          MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))
    -> TcM
         (HsWrapper,
          MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)))
    forall a b. (a -> b) -> a -> b
    $
                    -- Why mono_id in the BinderStack?
                    --    See Note [Relevant bindings and the binder stack]

                    SrcSpanAnnA
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
    setSrcSpanA SrcSpanAnnA
    bind_loc (TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
     -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc)))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    forall a b. (a -> b) -> a -> b
    $
                    GenLocated SrcSpanAnnN Name
    -> MatchGroup GhcRn (LHsExpr GhcRn)
    -> ExpSigmaType
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    tcMatchesFun (SrcSpanAnnN -> Name -> GenLocated SrcSpanAnnN Name
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnN
    nm_loc Name
    mono_name) MatchGroup GhcRn (LHsExpr GhcRn)
    matches
                                 (Kind -> ExpSigmaType
    mkCheckExpType Kind
    rho_ty)

           -- We make a funny AbsBinds, abstracting over nothing,
           -- just so we have somewhere to put the SpecPrags.
           -- Otherwise we could just use the FunBind
           -- Hence poly_id2 is just a clone of poly_id;
           -- We re-use mono-name, but we could equally well use a fresh one

           ; let prag_sigs :: [LSig GhcRn]
    prag_sigs = TcPragEnv -> Name -> [LSig GhcRn]
    lookupPragEnv TcPragEnv
    prag_fn Name
    name
                 poly_id2 :: TcId
    poly_id2  = HasDebugCallStack => Name -> Kind -> Kind -> TcId
    Name -> Kind -> Kind -> TcId
    mkLocalId Name
    mono_name (TcId -> Kind
    idMult TcId
    poly_id) (TcId -> Kind
    idType TcId
    poly_id)
           ; [LTcSpecPrag]
    spec_prags <- TcId -> [LSig GhcRn] -> TcM [LTcSpecPrag]
    tcSpecPrags    TcId
    poly_id [LSig GhcRn]
    prag_sigs
           ; TcId
    poly_id    <- TcId -> [LSig GhcRn] -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    addInlinePrags TcId
    poly_id [LSig GhcRn]
    prag_sigs

           ; Module
    mod <- IOEnv (Env TcGblEnv TcLclEnv) Module
    forall (m :: * -> *). HasModule m => m Module
    getModule
           ; [CoreTickish]
    tick <- SrcSpan -> TcId -> Module -> [LSig GhcRn] -> TcM [CoreTickish]
    funBindTicks (SrcSpanAnnN -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA SrcSpanAnnN
    nm_loc) TcId
    poly_id Module
    mod [LSig GhcRn]
    prag_sigs

           ; let bind' :: HsBindLR GhcTc GhcTc
    bind' = FunBind { fun_id :: LIdP GhcTc
    fun_id      = SrcSpanAnnN -> TcId -> GenLocated SrcSpanAnnN TcId
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnN
    nm_loc TcId
    poly_id2
                                 , fun_matches :: MatchGroup GhcTc (LHsExpr GhcTc)
    fun_matches = MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    MatchGroup GhcTc (LHsExpr GhcTc)
    matches'
                                 , fun_ext :: XFunBind GhcTc GhcTc
    fun_ext     = HsWrapper
    wrap_gen HsWrapper -> HsWrapper -> HsWrapper
    <.> HsWrapper
    wrap_res
                                 , fun_tick :: [CoreTickish]
    fun_tick    = [CoreTickish]
    tick }

                 export :: ABExport GhcTc
    export = ABE { abe_ext :: XABE GhcTc
    abe_ext   = NoExtField
    XABE GhcTc
    noExtField
                              , abe_wrap :: HsWrapper
    abe_wrap  = HsWrapper
    idHsWrapper
                              , abe_poly :: IdP GhcTc
    abe_poly  = TcId
    IdP GhcTc
    poly_id
                              , abe_mono :: IdP GhcTc
    abe_mono  = TcId
    IdP GhcTc
    poly_id2
                              , abe_prags :: TcSpecPrags
    abe_prags = [LTcSpecPrag] -> TcSpecPrags
    SpecPrags [LTcSpecPrag]
    spec_prags }

                 abs_bind :: GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    abs_bind = SrcSpanAnnA
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnA
    bind_loc (HsBindLR GhcTc GhcTc
     -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
                            AbsBinds { abs_ext :: XAbsBinds GhcTc GhcTc
    abs_ext      = NoExtField
    XAbsBinds GhcTc GhcTc
    noExtField
                                     , abs_tvs :: [TcId]
    abs_tvs      = []
                                     , abs_ev_vars :: [TcId]
    abs_ev_vars  = []
                                     , abs_ev_binds :: [TcEvBinds]
    abs_ev_binds = []
                                     , abs_exports :: [ABExport GhcTc]
    abs_exports  = [ABExport GhcTc
    export]
                                     , abs_binds :: LHsBinds GhcTc
    abs_binds    = GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. a -> Bag a
    unitBag (SrcSpanAnnA
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnA
    bind_loc HsBindLR GhcTc GhcTc
    bind')
                                     , abs_sig :: Bool
    abs_sig      = Bool
    True }

           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. a -> Bag a
    unitBag GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    abs_bind, [TcId
    poly_id]) }

    tcPolyCheck TcPragEnv
    _prag_fn TcIdSigInfo
    sig LHsBind GhcRn
    bind
      = String
    -> SDoc
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "tcPolyCheck" (TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    sig SDoc -> SDoc -> SDoc
    $$ GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn) -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    LHsBind GhcRn
    bind)

    funBindTicks :: SrcSpan -> TcId -> Module -> [LSig GhcRn]
                 -> TcM [CoreTickish]
    funBindTicks :: SrcSpan -> TcId -> Module -> [LSig GhcRn] -> TcM [CoreTickish]
    funBindTicks SrcSpan
    loc TcId
    fun_id Module
    mod [LSig GhcRn]
    sigs
      | (Maybe (GenLocated SrcSpan StringLiteral)
    mb_cc_str : [Maybe (GenLocated SrcSpan StringLiteral)]
    _) <- [ Maybe (GenLocated SrcSpan StringLiteral)
    Maybe (XRec GhcRn StringLiteral)
    cc_name | L SrcSpanAnnA
    _ (SCCFunSig XSCCFunSig GhcRn
    _ SourceText
    _ LIdP GhcRn
    _ Maybe (XRec GhcRn StringLiteral)
    cc_name) <- [GenLocated SrcSpanAnnA (Sig GhcRn)]
    [LSig GhcRn]
    sigs ]
          -- this can only be a singleton list, as duplicate pragmas are rejected
          -- by the renamer
      , let cc_str :: FastString
    cc_str
              | Just GenLocated SrcSpan StringLiteral
    cc_str <- Maybe (GenLocated SrcSpan StringLiteral)
    mb_cc_str
              = StringLiteral -> FastString
    sl_fs (StringLiteral -> FastString) -> StringLiteral -> FastString
    forall a b. (a -> b) -> a -> b
    $ GenLocated SrcSpan StringLiteral -> StringLiteral
    forall l e. GenLocated l e -> e
    unLoc GenLocated SrcSpan StringLiteral
    cc_str
              | Bool
    otherwise
              = Name -> FastString
    forall a. NamedThing a => a -> FastString
    getOccFS (TcId -> Name
    Var.varName TcId
    fun_id)
            cc_name :: FastString
    cc_name = ModuleName -> FastString
    moduleNameFS (Module -> ModuleName
    forall unit. GenModule unit -> ModuleName
    moduleName Module
    mod) FastString -> FastString -> FastString
    `appendFS` Char -> FastString -> FastString
    consFS Char
    '.' FastString
    cc_str
      = do
          CCFlavour
    flavour <- CostCentreIndex -> CCFlavour
    DeclCC (CostCentreIndex -> CCFlavour)
    -> IOEnv (Env TcGblEnv TcLclEnv) CostCentreIndex
    -> IOEnv (Env TcGblEnv TcLclEnv) CCFlavour
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    <$> FastString -> IOEnv (Env TcGblEnv TcLclEnv) CostCentreIndex
    getCCIndexTcM FastString
    cc_name
          let cc :: CostCentre
    cc = FastString -> Module -> SrcSpan -> CCFlavour -> CostCentre
    mkUserCC FastString
    cc_name Module
    mod SrcSpan
    loc CCFlavour
    flavour
          [CoreTickish] -> TcM [CoreTickish]
    forall (m :: * -> *) a. Monad m => a -> m a
    return [CostCentre -> Bool -> Bool -> CoreTickish
    forall (pass :: TickishPass).
    CostCentre -> Bool -> Bool -> GenTickish pass
    ProfNote CostCentre
    cc Bool
    True Bool
    True]
      | Bool
    otherwise
      = [CoreTickish] -> TcM [CoreTickish]
    forall (m :: * -> *) a. Monad m => a -> m a
    return []

    {- Note [Instantiate sig with fresh variables]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    It's vital to instantiate a type signature with fresh variables.
    For example:
          type T = forall a. [a] -> [a]
          f :: T;
          f = g where { g :: T; g = <rhs> }

     We must not use the same 'a' from the defn of T at both places!!
    (Instantiation is only necessary because of type synonyms.  Otherwise,
    it's all cool; each signature has distinct type variables from the renamer.)
    -}

    {- *********************************************************************
    *                                                                      *
                             tcPolyInfer
    *                                                                      *
    ********************************************************************* -}

    tcPolyInfer
      :: RecFlag       -- Whether it's recursive after breaking
                       -- dependencies based on type signatures
      -> TcPragEnv -> TcSigFun
      -> Bool         -- True <=> apply the monomorphism restriction
      -> [LHsBind GhcRn]
      -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyInfer :: RecFlag
    -> TcPragEnv
    -> TcSigFun
    -> Bool
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [TcId])
    tcPolyInfer RecFlag
    rec_tc TcPragEnv
    prag_fn TcSigFun
    tc_sig_fn Bool
    mono [LHsBind GhcRn]
    bind_list
      = do { (TcLevel
    tclvl, WantedConstraints
    wanted, (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    binds', [MonoBindInfo]
    mono_infos))
                 <- TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM
         (TcLevel, WantedConstraints, (LHsBinds GhcTc, [MonoBindInfo]))
    forall a. TcM a -> TcM (TcLevel, WantedConstraints, a)
    pushLevelAndCaptureConstraints  (TcM (LHsBinds GhcTc, [MonoBindInfo])
     -> TcM
          (TcLevel, WantedConstraints, (LHsBinds GhcTc, [MonoBindInfo])))
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM
         (TcLevel, WantedConstraints, (LHsBinds GhcTc, [MonoBindInfo]))
    forall a b. (a -> b) -> a -> b
    $
                    RecFlag
    -> TcSigFun
    -> LetBndrSpec
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    tcMonoBinds RecFlag
    rec_tc TcSigFun
    tc_sig_fn LetBndrSpec
    LetLclBndr [LHsBind GhcRn]
    bind_list

           ; let name_taus :: [(Name, Kind)]
    name_taus  = [ (MonoBindInfo -> Name
    mbi_poly_name MonoBindInfo
    info, TcId -> Kind
    idType (MonoBindInfo -> TcId
    mbi_mono_id MonoBindInfo
    info))
                              | MonoBindInfo
    info <- [MonoBindInfo]
    mono_infos ]
                 sigs :: [TcIdSigInst]
    sigs       = [ TcIdSigInst
    sig | MBI { mbi_sig :: MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig = Just TcIdSigInst
    sig } <- [MonoBindInfo]
    mono_infos ]
                 infer_mode :: InferMode
    infer_mode = if Bool
    mono then InferMode
    ApplyMR else InferMode
    NoRestrictions

           ; (TcIdSigInst -> TcRn ()) -> [TcIdSigInst] -> TcRn ()
    forall (t :: * -> *) (m :: * -> *) a b.
    (Foldable t, Monad m) =>
    (a -> m b) -> t a -> m ()
    mapM_ (Bool -> TcIdSigInst -> TcRn ()
    checkOverloadedSig Bool
    mono) [TcIdSigInst]
    sigs

           ; String -> SDoc -> TcRn ()
    traceTc String
    "simplifyInfer call" (TcLevel -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcLevel
    tclvl SDoc -> SDoc -> SDoc
    $$ [(Name, Kind)] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [(Name, Kind)]
    name_taus SDoc -> SDoc -> SDoc
    $$ WantedConstraints -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr WantedConstraints
    wanted)
           ; ([TcId]
    qtvs, [TcId]
    givens, TcEvBinds
    ev_binds, Bool
    insoluble)
                     <- TcLevel
    -> InferMode
    -> [TcIdSigInst]
    -> [(Name, Kind)]
    -> WantedConstraints
    -> TcM ([TcId], [TcId], TcEvBinds, Bool)
    simplifyInfer TcLevel
    tclvl InferMode
    infer_mode [TcIdSigInst]
    sigs [(Name, Kind)]
    name_taus WantedConstraints
    wanted

           ; let inferred_theta :: TcThetaType
    inferred_theta = (TcId -> Kind) -> [TcId] -> TcThetaType
    forall a b. (a -> b) -> [a] -> [b]
    map TcId -> Kind
    evVarPred [TcId]
    givens
           ; [ABExport GhcTc]
    exports <- TcM [ABExport GhcTc] -> TcM [ABExport GhcTc]
    forall r. TcM r -> TcM r
    checkNoErrs (TcM [ABExport GhcTc] -> TcM [ABExport GhcTc])
    -> TcM [ABExport GhcTc] -> TcM [ABExport GhcTc]
    forall a b. (a -> b) -> a -> b
    $
                        (MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) (ABExport GhcTc))
    -> [MonoBindInfo] -> TcM [ABExport GhcTc]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM (TcPragEnv
    -> Bool
    -> [TcId]
    -> TcThetaType
    -> MonoBindInfo
    -> IOEnv (Env TcGblEnv TcLclEnv) (ABExport GhcTc)
    mkExport TcPragEnv
    prag_fn Bool
    insoluble [TcId]
    qtvs TcThetaType
    inferred_theta) [MonoBindInfo]
    mono_infos

           ; SrcSpan
    loc <- TcRn SrcSpan
    getSrcSpanM
           ; let poly_ids :: [TcId]
    poly_ids = (ABExport GhcTc -> TcId) -> [ABExport GhcTc] -> [TcId]
    forall a b. (a -> b) -> [a] -> [b]
    map ABExport GhcTc -> TcId
    forall p. ABExport p -> IdP p
    abe_poly [ABExport GhcTc]
    exports
                 abs_bind :: GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    abs_bind = SrcSpanAnnA
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall l e. l -> e -> GenLocated l e
    L (SrcSpan -> SrcSpanAnnA
    forall ann. SrcSpan -> SrcAnn ann
    noAnnSrcSpan SrcSpan
    loc) (HsBindLR GhcTc GhcTc
     -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
                            AbsBinds { abs_ext :: XAbsBinds GhcTc GhcTc
    abs_ext = NoExtField
    XAbsBinds GhcTc GhcTc
    noExtField
                                     , abs_tvs :: [TcId]
    abs_tvs = [TcId]
    qtvs
                                     , abs_ev_vars :: [TcId]
    abs_ev_vars = [TcId]
    givens, abs_ev_binds :: [TcEvBinds]
    abs_ev_binds = [TcEvBinds
    ev_binds]
                                     , abs_exports :: [ABExport GhcTc]
    abs_exports = [ABExport GhcTc]
    exports, abs_binds :: LHsBinds GhcTc
    abs_binds = Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    LHsBinds GhcTc
    binds'
                                     , abs_sig :: Bool
    abs_sig = Bool
    False }

           ; String -> SDoc -> TcRn ()
    traceTc String
    "Binding:" ([(TcId, Kind)] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr ([TcId]
    poly_ids [TcId] -> TcThetaType -> [(TcId, Kind)]
    forall a b. [a] -> [b] -> [(a, b)]
    `zip` (TcId -> Kind) -> [TcId] -> TcThetaType
    forall a b. (a -> b) -> [a] -> [b]
    map TcId -> Kind
    idType [TcId]
    poly_ids))
           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)), [TcId])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. a -> Bag a
    unitBag GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    abs_bind, [TcId]
    poly_ids) }
             -- poly_ids are guaranteed zonked by mkExport

    --------------
    mkExport :: TcPragEnv
             -> Bool                        -- True <=> there was an insoluble type error
                                            --          when typechecking the bindings
             -> [TyVar] -> TcThetaType      -- Both already zonked
             -> MonoBindInfo
             -> TcM (ABExport GhcTc)
    -- Only called for generalisation plan InferGen, not by CheckGen or NoGen
    --
    -- mkExport generates exports with
    --      zonked type variables,
    --      zonked poly_ids
    -- The former is just because no further unifications will change
    -- the quantified type variables, so we can fix their final form
    -- right now.
    -- The latter is needed because the poly_ids are used to extend the
    -- type environment; see the invariant on GHC.Tc.Utils.Env.tcExtendIdEnv

    -- Pre-condition: the qtvs and theta are already zonked

    mkExport :: TcPragEnv
    -> Bool
    -> [TcId]
    -> TcThetaType
    -> MonoBindInfo
    -> IOEnv (Env TcGblEnv TcLclEnv) (ABExport GhcTc)
    mkExport TcPragEnv
    prag_fn Bool
    insoluble [TcId]
    qtvs TcThetaType
    theta
             mono_info :: MonoBindInfo
    mono_info@(MBI { mbi_poly_name :: MonoBindInfo -> Name
    mbi_poly_name = Name
    poly_name
                            , mbi_sig :: MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig       = Maybe TcIdSigInst
    mb_sig
                            , mbi_mono_id :: MonoBindInfo -> TcId
    mbi_mono_id   = TcId
    mono_id })
      = do  { Kind
    mono_ty <- Kind -> TcM Kind
    zonkTcType (TcId -> Kind
    idType TcId
    mono_id)
            ; TcId
    poly_id <- Bool
    -> [TcId]
    -> TcThetaType
    -> Name
    -> Maybe TcIdSigInst
    -> Kind
    -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    mkInferredPolyId Bool
    insoluble [TcId]
    qtvs TcThetaType
    theta Name
    poly_name Maybe TcIdSigInst
    mb_sig Kind
    mono_ty

            -- NB: poly_id has a zonked type
            ; TcId
    poly_id <- TcId -> [LSig GhcRn] -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    addInlinePrags TcId
    poly_id [LSig GhcRn]
    prag_sigs
            ; [LTcSpecPrag]
    spec_prags <- TcId -> [LSig GhcRn] -> TcM [LTcSpecPrag]
    tcSpecPrags TcId
    poly_id [LSig GhcRn]
    prag_sigs
                    -- tcPrags requires a zonked poly_id

            -- See Note [Impedance matching]
            -- NB: we have already done checkValidType, including an ambiguity check,
            --     on the type; either when we checked the sig or in mkInferredPolyId
            ; let poly_ty :: Kind
    poly_ty     = TcId -> Kind
    idType TcId
    poly_id
                  sel_poly_ty :: Kind
    sel_poly_ty = [TcId] -> TcThetaType -> Kind -> Kind
    mkInfSigmaTy [TcId]
    qtvs TcThetaType
    theta Kind
    mono_ty
                    -- This type is just going into tcSubType,
                    -- so Inferred vs. Specified doesn't matter

            ; HsWrapper
    wrap <- if Kind
    sel_poly_ty Kind -> Kind -> Bool
    `eqType` Kind
    poly_ty  -- NB: eqType ignores visibility
                      then HsWrapper -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    forall (m :: * -> *) a. Monad m => a -> m a
    return HsWrapper
    idHsWrapper  -- Fast path; also avoids complaint when we infer
                                               -- an ambiguous type and have AllowAmbiguousType
                                               -- e..g infer  x :: forall a. F a -> Int
                      else (TidyEnv -> TcM (TidyEnv, SDoc))
    -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    forall a. (TidyEnv -> TcM (TidyEnv, SDoc)) -> TcM a -> TcM a
    addErrCtxtM (MonoBindInfo -> Kind -> Kind -> TidyEnv -> TcM (TidyEnv, SDoc)
    mk_impedance_match_msg MonoBindInfo
    mono_info Kind
    sel_poly_ty Kind
    poly_ty) (IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
     -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper)
    -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    forall a b. (a -> b) -> a -> b
    $
                           UserTypeCtxt
    -> Kind -> Kind -> IOEnv (Env TcGblEnv TcLclEnv) HsWrapper
    tcSubTypeSigma UserTypeCtxt
    sig_ctxt Kind
    sel_poly_ty Kind
    poly_ty

            ; Bool
    warn_missing_sigs <- WarningFlag -> TcRnIf TcGblEnv TcLclEnv Bool
    forall gbl lcl. WarningFlag -> TcRnIf gbl lcl Bool
    woptM WarningFlag
    Opt_WarnMissingLocalSignatures
            ; Bool -> TcRn () -> TcRn ()
    forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
    when Bool
    warn_missing_sigs (TcRn () -> TcRn ()) -> TcRn () -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
                  WarningFlag -> TcId -> Maybe TcIdSigInst -> TcRn ()
    localSigWarn WarningFlag
    Opt_WarnMissingLocalSignatures TcId
    poly_id Maybe TcIdSigInst
    mb_sig

            ; ABExport GhcTc -> IOEnv (Env TcGblEnv TcLclEnv) (ABExport GhcTc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (ABE { abe_ext :: XABE GhcTc
    abe_ext = NoExtField
    XABE GhcTc
    noExtField
                          , abe_wrap :: HsWrapper
    abe_wrap = HsWrapper
    wrap
                            -- abe_wrap :: idType poly_id ~ (forall qtvs. theta => mono_ty)
                          , abe_poly :: IdP GhcTc
    abe_poly  = TcId
    IdP GhcTc
    poly_id
                          , abe_mono :: IdP GhcTc
    abe_mono  = TcId
    IdP GhcTc
    mono_id
                          , abe_prags :: TcSpecPrags
    abe_prags = [LTcSpecPrag] -> TcSpecPrags
    SpecPrags [LTcSpecPrag]
    spec_prags }) }
      where
        prag_sigs :: [LSig GhcRn]
    prag_sigs = TcPragEnv -> Name -> [LSig GhcRn]
    lookupPragEnv TcPragEnv
    prag_fn Name
    poly_name
        sig_ctxt :: UserTypeCtxt
    sig_ctxt  = Name -> UserTypeCtxt
    InfSigCtxt Name
    poly_name

    mkInferredPolyId :: Bool  -- True <=> there was an insoluble error when
                              --          checking the binding group for this Id
                     -> [TyVar] -> TcThetaType
                     -> Name -> Maybe TcIdSigInst -> TcType
                     -> TcM TcId
    mkInferredPolyId :: Bool
    -> [TcId]
    -> TcThetaType
    -> Name
    -> Maybe TcIdSigInst
    -> Kind
    -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    mkInferredPolyId Bool
    insoluble [TcId]
    qtvs TcThetaType
    inferred_theta Name
    poly_name Maybe TcIdSigInst
    mb_sig_inst Kind
    mono_ty
      | Just (TISI { sig_inst_sig :: TcIdSigInst -> TcIdSigInfo
    sig_inst_sig = TcIdSigInfo
    sig })  <- Maybe TcIdSigInst
    mb_sig_inst
      , CompleteSig { sig_bndr :: TcIdSigInfo -> TcId
    sig_bndr = TcId
    poly_id } <- TcIdSigInfo
    sig
      = TcId -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall (m :: * -> *) a. Monad m => a -> m a
    return TcId
    poly_id

      | Bool
    otherwise  -- Either no type sig or partial type sig
      = IOEnv (Env TcGblEnv TcLclEnv) TcId
    -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall r. TcM r -> TcM r
    checkNoErrs (IOEnv (Env TcGblEnv TcLclEnv) TcId
     -> IOEnv (Env TcGblEnv TcLclEnv) TcId)
    -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall a b. (a -> b) -> a -> b
    $  -- The checkNoErrs ensures that if the type is ambiguous
                       -- we don't carry on to the impedance matching, and generate
                       -- a duplicate ambiguity error.  There is a similar
                       -- checkNoErrs for complete type signatures too.
        do { FamInstEnvs
    fam_envs <- TcM FamInstEnvs
    tcGetFamInstEnvs
           ; let (TcCoercionR
    _co, Kind
    mono_ty') = FamInstEnvs -> Role -> Kind -> (TcCoercionR, Kind)
    normaliseType FamInstEnvs
    fam_envs Role
    Nominal Kind
    mono_ty
                   -- Unification may not have normalised the type,
                   -- so do it here to make it as uncomplicated as possible.
                   -- Example: f :: [F Int] -> Bool
                   -- should be rewritten to f :: [Char] -> Bool, if possible
                   --
                   -- We can discard the coercion _co, because we'll reconstruct
                   -- it in the call to tcSubType below

           ; ([InvisTVBinder]
    binders, TcThetaType
    theta') <- TcThetaType
    -> TcTyVarSet
    -> [TcId]
    -> Maybe TcIdSigInst
    -> TcM ([InvisTVBinder], TcThetaType)
    chooseInferredQuantifiers TcThetaType
    inferred_theta
                                    (Kind -> TcTyVarSet
    tyCoVarsOfType Kind
    mono_ty') [TcId]
    qtvs Maybe TcIdSigInst
    mb_sig_inst

           ; let inferred_poly_ty :: Kind
    inferred_poly_ty = [InvisTVBinder] -> Kind -> Kind
    mkInvisForAllTys [InvisTVBinder]
    binders (TcThetaType -> Kind -> Kind
    mkPhiTy TcThetaType
    theta' Kind
    mono_ty')

           ; String -> SDoc -> TcRn ()
    traceTc String
    "mkInferredPolyId" ([SDoc] -> SDoc
    vcat [Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    poly_name, [TcId] -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr [TcId]
    qtvs, TcThetaType -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcThetaType
    theta'
                                              , Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    inferred_poly_ty])
           ; Bool -> TcRn () -> TcRn ()
    forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
    unless Bool
    insoluble (TcRn () -> TcRn ()) -> TcRn () -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
             (TidyEnv -> TcM (TidyEnv, SDoc)) -> TcRn () -> TcRn ()
    forall a. (TidyEnv -> TcM (TidyEnv, SDoc)) -> TcM a -> TcM a
    addErrCtxtM (Name -> Kind -> TidyEnv -> TcM (TidyEnv, SDoc)
    mk_inf_msg Name
    poly_name Kind
    inferred_poly_ty) (TcRn () -> TcRn ()) -> TcRn () -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
             UserTypeCtxt -> Kind -> TcRn ()
    checkValidType (Name -> UserTypeCtxt
    InfSigCtxt Name
    poly_name) Kind
    inferred_poly_ty
             -- See Note [Validity of inferred types]
             -- If we found an insoluble error in the function definition, don't
             -- do this check; otherwise (#14000) we may report an ambiguity
             -- error for a rather bogus type.

           ; TcId -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    forall (m :: * -> *) a. Monad m => a -> m a
    return (HasDebugCallStack => Name -> Kind -> Kind -> TcId
    Name -> Kind -> Kind -> TcId
    mkLocalId Name
    poly_name Kind
    Many Kind
    inferred_poly_ty) }

    chooseInferredQuantifiers :: TcThetaType   -- inferred
                              -> TcTyVarSet    -- tvs free in tau type
                              -> [TcTyVar]     -- inferred quantified tvs
                              -> Maybe TcIdSigInst
                              -> TcM ([InvisTVBinder], TcThetaType)
    chooseInferredQuantifiers :: TcThetaType
    -> TcTyVarSet
    -> [TcId]
    -> Maybe TcIdSigInst
    -> TcM ([InvisTVBinder], TcThetaType)
    chooseInferredQuantifiers TcThetaType
    inferred_theta TcTyVarSet
    tau_tvs [TcId]
    qtvs Maybe TcIdSigInst
    Nothing
      = -- No type signature (partial or complete) for this binder,
        do { let free_tvs :: TcTyVarSet
    free_tvs = TcTyVarSet -> TcTyVarSet
    closeOverKinds (TcThetaType -> TcTyVarSet -> TcTyVarSet
    growThetaTyVars TcThetaType
    inferred_theta TcTyVarSet
    tau_tvs)
                            -- Include kind variables!  #7916
                 my_theta :: TcThetaType
    my_theta = TcTyVarSet -> TcThetaType -> TcThetaType
    pickCapturedPreds TcTyVarSet
    free_tvs TcThetaType
    inferred_theta
                 binders :: [InvisTVBinder]
    binders  = [ Specificity -> TcId -> InvisTVBinder
    forall vis. vis -> TcId -> VarBndr TcId vis
    mkTyVarBinder Specificity
    InferredSpec TcId
    tv
                            | TcId
    tv <- [TcId]
    qtvs
                            , TcId
    tv TcId -> TcTyVarSet -> Bool
    `elemVarSet` TcTyVarSet
    free_tvs ]
           ; ([InvisTVBinder], TcThetaType)
    -> TcM ([InvisTVBinder], TcThetaType)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([InvisTVBinder]
    binders, TcThetaType
    my_theta) }

    chooseInferredQuantifiers TcThetaType
    inferred_theta TcTyVarSet
    tau_tvs [TcId]
    qtvs
                              (Just (TISI { sig_inst_sig :: TcIdSigInst -> TcIdSigInfo
    sig_inst_sig   = TcIdSigInfo
    sig  -- Always PartialSig
                                          , sig_inst_wcx :: TcIdSigInst -> Maybe Kind
    sig_inst_wcx   = Maybe Kind
    wcx
                                          , sig_inst_theta :: TcIdSigInst -> TcThetaType
    sig_inst_theta = TcThetaType
    annotated_theta
                                          , sig_inst_skols :: TcIdSigInst -> [(Name, InvisTVBinder)]
    sig_inst_skols = [(Name, InvisTVBinder)]
    annotated_tvs }))
      = -- Choose quantifiers for a partial type signature
        do { let ([Name]
    psig_qtv_nms, [InvisTVBinder]
    psig_qtv_bndrs) = [(Name, InvisTVBinder)] -> ([Name], [InvisTVBinder])
    forall a b. [(a, b)] -> ([a], [b])
    unzip [(Name, InvisTVBinder)]
    annotated_tvs
           ; [InvisTVBinder]
    psig_qtv_bndrs <- (InvisTVBinder -> IOEnv (Env TcGblEnv TcLclEnv) InvisTVBinder)
    -> [InvisTVBinder] -> IOEnv (Env TcGblEnv TcLclEnv) [InvisTVBinder]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM InvisTVBinder -> IOEnv (Env TcGblEnv TcLclEnv) InvisTVBinder
    forall spec. VarBndr TcId spec -> TcM (VarBndr TcId spec)
    zonkInvisTVBinder [InvisTVBinder]
    psig_qtv_bndrs
           ; let psig_qtvs :: [TcId]
    psig_qtvs    = (InvisTVBinder -> TcId) -> [InvisTVBinder] -> [TcId]
    forall a b. (a -> b) -> [a] -> [b]
    map InvisTVBinder -> TcId
    forall tv argf. VarBndr tv argf -> tv
    binderVar [InvisTVBinder]
    psig_qtv_bndrs
                 psig_qtv_set :: TcTyVarSet
    psig_qtv_set = [TcId] -> TcTyVarSet
    mkVarSet [TcId]
    psig_qtvs
                 psig_qtv_prs :: [(Name, TcId)]
    psig_qtv_prs = [Name]
    psig_qtv_nms [Name] -> [TcId] -> [(Name, TcId)]
    forall a b. [a] -> [b] -> [(a, b)]
    `zip` [TcId]
    psig_qtvs

                -- Check whether the quantified variables of the
                -- partial signature have been unified together
                -- See Note [Quantified variables in partial type signatures]
           ; ((Name, Name) -> TcRn ()) -> [(Name, Name)] -> TcRn ()
    forall (t :: * -> *) (m :: * -> *) a b.
    (Foldable t, Monad m) =>
    (a -> m b) -> t a -> m ()
    mapM_ (Name, Name) -> TcRn ()
    report_dup_tyvar_tv_err  ([(Name, TcId)] -> [(Name, Name)]
    findDupTyVarTvs [(Name, TcId)]
    psig_qtv_prs)

                -- Check whether a quantified variable of the partial type
                -- signature is not actually quantified.  How can that happen?
                -- See Note [Quantification and partial signatures] Wrinkle 4
                --     in GHC.Tc.Solver
           ; (Name -> TcRn ()) -> [Name] -> TcRn ()
    forall (t :: * -> *) (m :: * -> *) a b.
    (Foldable t, Monad m) =>
    (a -> m b) -> t a -> m ()
    mapM_ Name -> TcRn ()
    report_mono_sig_tv_err [ Name
    n | (Name
    n,TcId
    tv) <- [(Name, TcId)]
    psig_qtv_prs
                                              , Bool -> Bool
    not (TcId
    tv TcId -> [TcId] -> Bool
    forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
    `elem` [TcId]
    qtvs) ]

           ; TcThetaType
    annotated_theta      <- TcThetaType -> TcM TcThetaType
    zonkTcTypes TcThetaType
    annotated_theta
           ; (TcTyVarSet
    free_tvs, TcThetaType
    my_theta) <- TcTyVarSet
    -> TcThetaType -> Maybe Kind -> TcM (TcTyVarSet, TcThetaType)
    choose_psig_context TcTyVarSet
    psig_qtv_set TcThetaType
    annotated_theta Maybe Kind
    wcx

           ; let keep_me :: TcTyVarSet
    keep_me    = TcTyVarSet
    free_tvs TcTyVarSet -> TcTyVarSet -> TcTyVarSet
    `unionVarSet` TcTyVarSet
    psig_qtv_set
                 final_qtvs :: [InvisTVBinder]
    final_qtvs = [ Specificity -> TcId -> InvisTVBinder
    forall vis. vis -> TcId -> VarBndr TcId vis
    mkTyVarBinder Specificity
    vis TcId
    tv
                              | TcId
    tv <- [TcId]
    qtvs -- Pulling from qtvs maintains original order
                              , TcId
    tv TcId -> TcTyVarSet -> Bool
    `elemVarSet` TcTyVarSet
    keep_me
                              , let vis :: Specificity
    vis = case TcId -> [InvisTVBinder] -> Maybe Specificity
    forall var flag. Eq var => var -> [VarBndr var flag] -> Maybe flag
    lookupVarBndr TcId
    tv [InvisTVBinder]
    psig_qtv_bndrs of
                                      Just Specificity
    spec -> Specificity
    spec
                                      Maybe Specificity
    Nothing   -> Specificity
    InferredSpec ]

           ; ([InvisTVBinder], TcThetaType)
    -> TcM ([InvisTVBinder], TcThetaType)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([InvisTVBinder]
    final_qtvs, TcThetaType
    my_theta) }
      where
        report_dup_tyvar_tv_err :: (Name, Name) -> TcRn ()
    report_dup_tyvar_tv_err (Name
    n1,Name
    n2)
          | PartialSig { psig_name :: TcIdSigInfo -> Name
    psig_name = Name
    fn_name, psig_hs_ty :: TcIdSigInfo -> LHsSigWcType GhcRn
    psig_hs_ty = LHsSigWcType GhcRn
    hs_ty } <- TcIdSigInfo
    sig
          = SDoc -> TcRn ()
    addErrTc (SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "Couldn't match" SDoc -> SDoc -> SDoc
    <+> SDoc -> SDoc
    quotes (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    n1)
                            SDoc -> SDoc -> SDoc
    <+> String -> SDoc
    text String
    "with" SDoc -> SDoc -> SDoc
    <+> SDoc -> SDoc
    quotes (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    n2))
                         BKey
    2 (SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "both bound by the partial type signature:")
                               BKey
    2 (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    fn_name SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> HsWildCardBndrs GhcRn (GenLocated SrcSpanAnnA (HsSigType GhcRn))
    -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr HsWildCardBndrs GhcRn (GenLocated SrcSpanAnnA (HsSigType GhcRn))
    LHsSigWcType GhcRn
    hs_ty)))

          | Bool
    otherwise -- Can't happen; by now we know it's a partial sig
          = String -> SDoc -> TcRn ()
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "report_tyvar_tv_err" (TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    sig)

        report_mono_sig_tv_err :: Name -> TcRn ()
    report_mono_sig_tv_err Name
    n
          | PartialSig { psig_name :: TcIdSigInfo -> Name
    psig_name = Name
    fn_name, psig_hs_ty :: TcIdSigInfo -> LHsSigWcType GhcRn
    psig_hs_ty = LHsSigWcType GhcRn
    hs_ty } <- TcIdSigInfo
    sig
          = SDoc -> TcRn ()
    addErrTc (SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "Can't quantify over" SDoc -> SDoc -> SDoc
    <+> SDoc -> SDoc
    quotes (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    n))
                         BKey
    2 (SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "bound by the partial type signature:")
                               BKey
    2 (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    fn_name SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> HsWildCardBndrs GhcRn (GenLocated SrcSpanAnnA (HsSigType GhcRn))
    -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr HsWildCardBndrs GhcRn (GenLocated SrcSpanAnnA (HsSigType GhcRn))
    LHsSigWcType GhcRn
    hs_ty)))
          | Bool
    otherwise -- Can't happen; by now we know it's a partial sig
          = String -> SDoc -> TcRn ()
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "report_mono_sig_tv_err" (TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    sig)

        choose_psig_context :: VarSet -> TcThetaType -> Maybe TcType
                            -> TcM (VarSet, TcThetaType)
        choose_psig_context :: TcTyVarSet
    -> TcThetaType -> Maybe Kind -> TcM (TcTyVarSet, TcThetaType)
    choose_psig_context TcTyVarSet
    _ TcThetaType
    annotated_theta Maybe Kind
    Nothing
          = do { let free_tvs :: TcTyVarSet
    free_tvs = TcTyVarSet -> TcTyVarSet
    closeOverKinds (TcThetaType -> TcTyVarSet
    tyCoVarsOfTypes TcThetaType
    annotated_theta
                                                TcTyVarSet -> TcTyVarSet -> TcTyVarSet
    `unionVarSet` TcTyVarSet
    tau_tvs)
               ; (TcTyVarSet, TcThetaType) -> TcM (TcTyVarSet, TcThetaType)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TcTyVarSet
    free_tvs, TcThetaType
    annotated_theta) }

        choose_psig_context TcTyVarSet
    psig_qtvs TcThetaType
    annotated_theta (Just Kind
    wc_var_ty)
          = do { let free_tvs :: TcTyVarSet
    free_tvs = TcTyVarSet -> TcTyVarSet
    closeOverKinds (TcThetaType -> TcTyVarSet -> TcTyVarSet
    growThetaTyVars TcThetaType
    inferred_theta TcTyVarSet
    seed_tvs)
                                -- growThetaVars just like the no-type-sig case
                                -- Omitting this caused #12844
                     seed_tvs :: TcTyVarSet
    seed_tvs = TcThetaType -> TcTyVarSet
    tyCoVarsOfTypes TcThetaType
    annotated_theta  -- These are put there
                                TcTyVarSet -> TcTyVarSet -> TcTyVarSet
    `unionVarSet` TcTyVarSet
    tau_tvs            --       by the user

               ; let keep_me :: TcTyVarSet
    keep_me  = TcTyVarSet
    psig_qtvs TcTyVarSet -> TcTyVarSet -> TcTyVarSet
    `unionVarSet` TcTyVarSet
    free_tvs
                     my_theta :: TcThetaType
    my_theta = TcTyVarSet -> TcThetaType -> TcThetaType
    pickCapturedPreds TcTyVarSet
    keep_me TcThetaType
    inferred_theta

               -- Fill in the extra-constraints wildcard hole with inferred_theta,
               -- so that the Hole constraint we have already emitted
               -- (in tcHsPartialSigType) can report what filled it in.
               -- NB: my_theta already includes all the annotated constraints
               ; TcThetaType
    diff_theta <- TcThetaType -> TcThetaType -> TcM TcThetaType
    findInferredDiff TcThetaType
    annotated_theta TcThetaType
    my_theta

               ; case Kind -> Maybe (TcId, TcCoercionR)
    tcGetCastedTyVar_maybe Kind
    wc_var_ty of
                   -- We know that wc_co must have type kind(wc_var) ~ Constraint, as it
                   -- comes from the checkExpectedKind in GHC.Tc.Gen.HsType.tcAnonWildCardOcc.
                   -- So, to make the kinds work out, we reverse the cast here.
                   Just (TcId
    wc_var, TcCoercionR
    wc_co) -> TcId -> Kind -> TcRn ()
    writeMetaTyVar TcId
    wc_var (TcThetaType -> Kind
    mk_ctuple TcThetaType
    diff_theta
                                                                  Kind -> TcCoercionR -> Kind
    `mkCastTy` TcCoercionR -> TcCoercionR
    mkTcSymCo TcCoercionR
    wc_co)
                   Maybe (TcId, TcCoercionR)
    Nothing              -> String -> SDoc -> TcRn ()
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "chooseInferredQuantifiers 1" (Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    wc_var_ty)

               ; String -> SDoc -> TcRn ()
    traceTc String
    "completeTheta" (SDoc -> TcRn ()) -> SDoc -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
                    [SDoc] -> SDoc
    vcat [ TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    sig
                         , String -> SDoc
    text String
    "annotated_theta:" SDoc -> SDoc -> SDoc
    <+> TcThetaType -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcThetaType
    annotated_theta
                         , String -> SDoc
    text String
    "inferred_theta:" SDoc -> SDoc -> SDoc
    <+> TcThetaType -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcThetaType
    inferred_theta
                         , String -> SDoc
    text String
    "my_theta:" SDoc -> SDoc -> SDoc
    <+> TcThetaType -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcThetaType
    my_theta
                         , String -> SDoc
    text String
    "diff_theta:" SDoc -> SDoc -> SDoc
    <+> TcThetaType -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcThetaType
    diff_theta ]
               ; (TcTyVarSet, TcThetaType) -> TcM (TcTyVarSet, TcThetaType)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TcTyVarSet
    free_tvs, TcThetaType
    annotated_theta TcThetaType -> TcThetaType -> TcThetaType
    forall a. [a] -> [a] -> [a]
    ++ TcThetaType
    diff_theta) }
                 -- Return (annotated_theta ++ diff_theta)
                 -- See Note [Extra-constraints wildcards]

        mk_ctuple :: TcThetaType -> Kind
    mk_ctuple TcThetaType
    preds = TcThetaType -> Kind
    mkBoxedTupleTy TcThetaType
    preds
           -- Hack alert!  See GHC.Tc.Gen.HsType:
           -- Note [Extra-constraint holes in partial type signatures]

    mk_impedance_match_msg :: MonoBindInfo
                           -> TcType -> TcType
                           -> TidyEnv -> TcM (TidyEnv, SDoc)
    -- This is a rare but rather awkward error messages
    mk_impedance_match_msg :: MonoBindInfo -> Kind -> Kind -> TidyEnv -> TcM (TidyEnv, SDoc)
    mk_impedance_match_msg (MBI { mbi_poly_name :: MonoBindInfo -> Name
    mbi_poly_name = Name
    name, mbi_sig :: MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig = Maybe TcIdSigInst
    mb_sig })
                           Kind
    inf_ty Kind
    sig_ty TidyEnv
    tidy_env
     = do { (TidyEnv
    tidy_env1, Kind
    inf_ty) <- TidyEnv -> Kind -> TcM (TidyEnv, Kind)
    zonkTidyTcType TidyEnv
    tidy_env  Kind
    inf_ty
          ; (TidyEnv
    tidy_env2, Kind
    sig_ty) <- TidyEnv -> Kind -> TcM (TidyEnv, Kind)
    zonkTidyTcType TidyEnv
    tidy_env1 Kind
    sig_ty
          ; let msg :: SDoc
    msg = [SDoc] -> SDoc
    vcat [ String -> SDoc
    text String
    "When checking that the inferred type"
                           , BKey -> SDoc -> SDoc
    nest BKey
    2 (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    inf_ty
                           , String -> SDoc
    text String
    "is as general as its" SDoc -> SDoc -> SDoc
    <+> SDoc
    what SDoc -> SDoc -> SDoc
    <+> String -> SDoc
    text String
    "signature"
                           , BKey -> SDoc -> SDoc
    nest BKey
    2 (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    sig_ty ]
          ; (TidyEnv, SDoc) -> TcM (TidyEnv, SDoc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TidyEnv
    tidy_env2, SDoc
    msg) }
      where
        what :: SDoc
    what = case Maybe TcIdSigInst
    mb_sig of
                 Maybe TcIdSigInst
    Nothing                     -> String -> SDoc
    text String
    "inferred"
                 Just TcIdSigInst
    sig | TcIdSigInst -> Bool
    isPartialSig TcIdSigInst
    sig -> String -> SDoc
    text String
    "(partial)"
                          | Bool
    otherwise        -> SDoc
    empty

    mk_inf_msg :: Name -> TcType -> TidyEnv -> TcM (TidyEnv, SDoc)
    mk_inf_msg :: Name -> Kind -> TidyEnv -> TcM (TidyEnv, SDoc)
    mk_inf_msg Name
    poly_name Kind
    poly_ty TidyEnv
    tidy_env
     = do { (TidyEnv
    tidy_env1, Kind
    poly_ty) <- TidyEnv -> Kind -> TcM (TidyEnv, Kind)
    zonkTidyTcType TidyEnv
    tidy_env Kind
    poly_ty
          ; let msg :: SDoc
    msg = [SDoc] -> SDoc
    vcat [ String -> SDoc
    text String
    "When checking the inferred type"
                           , BKey -> SDoc -> SDoc
    nest BKey
    2 (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    poly_name SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    poly_ty ]
          ; (TidyEnv, SDoc) -> TcM (TidyEnv, SDoc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return (TidyEnv
    tidy_env1, SDoc
    msg) }

    -- | Warn the user about polymorphic local binders that lack type signatures.
    localSigWarn :: WarningFlag -> Id -> Maybe TcIdSigInst -> TcM ()
    localSigWarn :: WarningFlag -> TcId -> Maybe TcIdSigInst -> TcRn ()
    localSigWarn WarningFlag
    flag TcId
    id Maybe TcIdSigInst
    mb_sig
      | Just TcIdSigInst
    _ <- Maybe TcIdSigInst
    mb_sig               = () -> TcRn ()
    forall (m :: * -> *) a. Monad m => a -> m a
    return ()
      | Bool -> Bool
    not (Kind -> Bool
    isSigmaTy (TcId -> Kind
    idType TcId
    id))    = () -> TcRn ()
    forall (m :: * -> *) a. Monad m => a -> m a
    return ()
      | Bool
    otherwise                      = WarningFlag -> SDoc -> TcId -> TcRn ()
    warnMissingSignatures WarningFlag
    flag SDoc
    msg TcId
    id
      where
        msg :: SDoc
    msg = String -> SDoc
    text String
    "Polymorphic local binding with no type signature:"

    warnMissingSignatures :: WarningFlag -> SDoc -> Id -> TcM ()
    warnMissingSignatures :: WarningFlag -> SDoc -> TcId -> TcRn ()
    warnMissingSignatures WarningFlag
    flag SDoc
    msg TcId
    id
      = do  { TidyEnv
    env0 <- TcM TidyEnv
    tcInitTidyEnv
            ; let (TidyEnv
    env1, Kind
    tidy_ty) = TidyEnv -> Kind -> (TidyEnv, Kind)
    tidyOpenType TidyEnv
    env0 (TcId -> Kind
    idType TcId
    id)
            ; WarnReason -> (TidyEnv, SDoc) -> TcRn ()
    addWarnTcM (WarningFlag -> WarnReason
    Reason WarningFlag
    flag) (TidyEnv
    env1, Kind -> SDoc
    mk_msg Kind
    tidy_ty) }
      where
        mk_msg :: Kind -> SDoc
    mk_msg Kind
    ty = [SDoc] -> SDoc
    sep [ SDoc
    msg, BKey -> SDoc -> SDoc
    nest BKey
    2 (SDoc -> SDoc) -> SDoc -> SDoc
    forall a b. (a -> b) -> a -> b
    $ Name -> SDoc
    forall a. NamedThing a => a -> SDoc
    pprPrefixName (TcId -> Name
    idName TcId
    id) SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    ty ]

    checkOverloadedSig :: Bool -> TcIdSigInst -> TcM ()
    -- Example:
    --   f :: Eq a => a -> a
    --   K f = e
    -- The MR applies, but the signature is overloaded, and it's
    -- best to complain about this directly
    -- c.f #11339
    checkOverloadedSig :: Bool -> TcIdSigInst -> TcRn ()
    checkOverloadedSig Bool
    monomorphism_restriction_applies TcIdSigInst
    sig
      | Bool -> Bool
    not (TcThetaType -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null (TcIdSigInst -> TcThetaType
    sig_inst_theta TcIdSigInst
    sig))
      , Bool
    monomorphism_restriction_applies
      , let orig_sig :: TcIdSigInfo
    orig_sig = TcIdSigInst -> TcIdSigInfo
    sig_inst_sig TcIdSigInst
    sig
      = SrcSpan -> TcRn () -> TcRn ()
    forall a. SrcSpan -> TcRn a -> TcRn a
    setSrcSpan (TcIdSigInfo -> SrcSpan
    sig_loc TcIdSigInfo
    orig_sig) (TcRn () -> TcRn ()) -> TcRn () -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
        SDoc -> TcRn ()
    forall a. SDoc -> TcRn a
    failWith (SDoc -> TcRn ()) -> SDoc -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $
        SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "Overloaded signature conflicts with monomorphism restriction")
           BKey
    2 (TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    orig_sig)
      | Bool
    otherwise
      = () -> TcRn ()
    forall (m :: * -> *) a. Monad m => a -> m a
    return ()

    {- Note [Partial type signatures and generalisation]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    If /any/ of the signatures in the group is a partial type signature
       f :: _ -> Int
    then we *always* use the InferGen plan, and hence tcPolyInfer.
    We do this even for a local binding with -XMonoLocalBinds, when
    we normally use NoGen.

    Reasons:
      * The TcSigInfo for 'f' has a unification variable for the '_',
        whose TcLevel is one level deeper than the current level.
        (See pushTcLevelM in tcTySig.)  But NoGen doesn't increase
        the TcLevel like InferGen, so we lose the level invariant.

      * The signature might be   f :: forall a. _ -> a
        so it really is polymorphic.  It's not clear what it would
        mean to use NoGen on this, and indeed the ASSERT in tcLhs,
        in the (Just sig) case, checks that if there is a signature
        then we are using LetLclBndr, and hence a nested AbsBinds with
        increased TcLevel

    It might be possible to fix these difficulties somehow, but there
    doesn't seem much point.  Indeed, adding a partial type signature is a
    way to get per-binding inferred generalisation.

    We apply the MR if /all/ of the partial signatures lack a context.
    In particular (#11016):
       f2 :: (?loc :: Int) => _
       f2 = ?loc
    It's stupid to apply the MR here.  This test includes an extra-constraints
    wildcard; that is, we don't apply the MR if you write
       f3 :: _ => blah

    Note [Quantified variables in partial type signatures]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Consider
      f :: forall a. a -> a -> _
      f x y = g x y
      g :: forall b. b -> b -> _
      g x y = [x, y]

    Here, 'f' and 'g' are mutually recursive, and we end up unifying 'a' and 'b'
    together, which is fine.  So we bind 'a' and 'b' to TyVarTvs, which can then
    unify with each other.

    But now consider:
      f :: forall a b. a -> b -> _
      f x y = [x, y]

    We want to get an error from this, because 'a' and 'b' get unified.
    So we make a test, one per partial signature, to check that the
    explicitly-quantified type variables have not been unified together.
    #14449 showed this up.

    Note [Extra-constraints wildcards]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Consider this from #18646
        class Foo x where
          foo :: x

        bar :: (Foo (), _) => f ()
        bar = pure foo

    We get [W] Foo (), [W] Applicative f.   When we do pickCapturedPreds in
    choose_psig_context, we'll discard Foo ()!  Usually would not quantify over
    such (closed) predicates.  So my_theta will be (Applicative f). But we really
    do want to quantify over (Foo ()) -- it was speicfied by the programmer.
    Solution: always return annotated_theta (user-specified) plus the extra piece
    diff_theta.

    Note [Validity of inferred types]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    We need to check inferred type for validity, in case it uses language
    extensions that are not turned on.  The principle is that if the user
    simply adds the inferred type to the program source, it'll compile fine.
    See #8883.

    Examples that might fail:
     - the type might be ambiguous

     - an inferred theta that requires type equalities e.g. (F a ~ G b)
                                    or multi-parameter type classes
     - an inferred type that includes unboxed tuples

    Note [Impedance matching]
    ~~~~~~~~~~~~~~~~~~~~~~~~~
    Consider
       f 0 x = x
       f n x = g [] (not x)

       g [] y = f 10 y
       g _  y = f 9  y

    After typechecking we'll get
      f_mono_ty :: a -> Bool -> Bool
      g_mono_ty :: [b] -> Bool -> Bool
    with constraints
      (Eq a, Num a)

    Note that f is polymorphic in 'a' and g in 'b'; and these are not linked.
    The types we really want for f and g are
       f :: forall a. (Eq a, Num a) => a -> Bool -> Bool
       g :: forall b. [b] -> Bool -> Bool

    We can get these by "impedance matching":
       tuple :: forall a b. (Eq a, Num a) => (a -> Bool -> Bool, [b] -> Bool -> Bool)
       tuple a b d1 d1 = let ...bind f_mono, g_mono in (f_mono, g_mono)

       f a d1 d2 = case tuple a Any d1 d2 of (f, g) -> f
       g b = case tuple Integer b dEqInteger dNumInteger of (f,g) -> g

    Suppose the shared quantified tyvars are qtvs and constraints theta.
    Then we want to check that
         forall qtvs. theta => f_mono_ty   is more polymorphic than   f's polytype
    and the proof is the impedance matcher.

    Notice that the impedance matcher may do defaulting.  See #7173.

    It also cleverly does an ambiguity check; for example, rejecting
       f :: F a -> F a
    where F is a non-injective type function.
    -}

    {-
    Note [SPECIALISE pragmas]
    ~~~~~~~~~~~~~~~~~~~~~~~~~
    There is no point in a SPECIALISE pragma for a non-overloaded function:
       reverse :: [a] -> [a]
       {-# SPECIALISE reverse :: [Int] -> [Int] #-}

    But SPECIALISE INLINE *can* make sense for GADTS:
       data Arr e where
         ArrInt :: !Int -> ByteArray# -> Arr Int
         ArrPair :: !Int -> Arr e1 -> Arr e2 -> Arr (e1, e2)

       (!:) :: Arr e -> Int -> e
       {-# SPECIALISE INLINE (!:) :: Arr Int -> Int -> Int #-}
       {-# SPECIALISE INLINE (!:) :: Arr (a, b) -> Int -> (a, b) #-}
       (ArrInt _ ba)     !: (I# i) = I# (indexIntArray# ba i)
       (ArrPair _ a1 a2) !: i      = (a1 !: i, a2 !: i)

    When (!:) is specialised it becomes non-recursive, and can usefully
    be inlined.  Scary!  So we only warn for SPECIALISE *without* INLINE
    for a non-overloaded function.

    ************************************************************************
    *                                                                      *
                             tcMonoBinds
    *                                                                      *
    ************************************************************************

    @tcMonoBinds@ deals with a perhaps-recursive group of HsBinds.
    The signatures have been dealt with already.
    -}

    data MonoBindInfo = MBI { MonoBindInfo -> Name
    mbi_poly_name :: Name
                            , MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig       :: Maybe TcIdSigInst
                            , MonoBindInfo -> TcId
    mbi_mono_id   :: TcId }

    tcMonoBinds :: RecFlag  -- Whether the binding is recursive for typechecking purposes
                            -- i.e. the binders are mentioned in their RHSs, and
                            --      we are not rescued by a type signature
                -> TcSigFun -> LetBndrSpec
                -> [LHsBind GhcRn]
                -> TcM (LHsBinds GhcTc, [MonoBindInfo])

    -- SPECIAL CASE 1: see Note [Inference for non-recursive function bindings]
    tcMonoBinds :: RecFlag
    -> TcSigFun
    -> LetBndrSpec
    -> [LHsBind GhcRn]
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    tcMonoBinds RecFlag
    is_rec TcSigFun
    sig_fn LetBndrSpec
    no_gen
               [ L SrcSpanAnnA
    b_loc (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = L SrcSpanAnnN
    nm_loc Name
    name
                                  , fun_matches :: forall idL idR. HsBindLR idL idR -> MatchGroup idR (LHsExpr idR)
    fun_matches = MatchGroup GhcRn (LHsExpr GhcRn)
    matches })]
                                 -- Single function binding,
      | RecFlag
    NonRecursive <- RecFlag
    is_rec   -- ...binder isn't mentioned in RHS
      , Maybe TcSigInfo
    Nothing <- TcSigFun
    sig_fn Name
    name   -- ...with no type signature
      = SrcSpanAnnA
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
    setSrcSpanA SrcSpanAnnA
    b_loc    (TcM (LHsBinds GhcTc, [MonoBindInfo])
     -> TcM (LHsBinds GhcTc, [MonoBindInfo]))
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    forall a b. (a -> b) -> a -> b
    $
        do  { ((HsWrapper
    co_fn, MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    matches'), Kind
    rhs_ty)
                <- (ExpSigmaType
     -> TcM
          (HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcM
         ((HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))),
          Kind)
    forall a. (ExpSigmaType -> TcM a) -> TcM (a, Kind)
    tcInfer ((ExpSigmaType
      -> TcM
           (HsWrapper,
            MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
     -> TcM
          ((HsWrapper,
            MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))),
           Kind))
    -> (ExpSigmaType
        -> TcM
             (HsWrapper,
              MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcM
         ((HsWrapper,
           MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))),
          Kind)
    forall a b. (a -> b) -> a -> b
    $ \ ExpSigmaType
    exp_ty ->
                   [TcBinder]
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    forall a. [TcBinder] -> TcM a -> TcM a
    tcExtendBinderStack [Name -> ExpSigmaType -> TopLevelFlag -> TcBinder
    TcIdBndr_ExpType Name
    name ExpSigmaType
    exp_ty TopLevelFlag
    NotTopLevel] (TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
     -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc)))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    forall a b. (a -> b) -> a -> b
    $
                      -- We extend the error context even for a non-recursive
                      -- function so that in type error messages we show the
                      -- type of the thing whose rhs we are type checking
                   GenLocated SrcSpanAnnN Name
    -> MatchGroup GhcRn (LHsExpr GhcRn)
    -> ExpSigmaType
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    tcMatchesFun (SrcSpanAnnN -> Name -> GenLocated SrcSpanAnnN Name
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnN
    nm_loc Name
    name) MatchGroup GhcRn (LHsExpr GhcRn)
    matches ExpSigmaType
    exp_ty

            ; TcId
    mono_id <- LetBndrSpec
    -> Name -> Kind -> Kind -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newLetBndr LetBndrSpec
    no_gen Name
    name Kind
    Many Kind
    rhs_ty
            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
     [MonoBindInfo])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
          [MonoBindInfo])
    forall (m :: * -> *) a. Monad m => a -> m a
    return (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. a -> Bag a
    unitBag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a b. (a -> b) -> a -> b
    $ SrcSpanAnnA
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnA
    b_loc (HsBindLR GhcTc GhcTc
     -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
                         FunBind { fun_id :: LIdP GhcTc
    fun_id = SrcSpanAnnN -> TcId -> GenLocated SrcSpanAnnN TcId
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnN
    nm_loc TcId
    mono_id,
                                   fun_matches :: MatchGroup GhcTc (LHsExpr GhcTc)
    fun_matches = MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    MatchGroup GhcTc (LHsExpr GhcTc)
    matches',
                                   fun_ext :: XFunBind GhcTc GhcTc
    fun_ext = XFunBind GhcTc GhcTc
    HsWrapper
    co_fn, fun_tick :: [CoreTickish]
    fun_tick = [] },
                      [MBI { mbi_poly_name :: Name
    mbi_poly_name = Name
    name
                           , mbi_sig :: Maybe TcIdSigInst
    mbi_sig       = Maybe TcIdSigInst
    forall a. Maybe a
    Nothing
                           , mbi_mono_id :: TcId
    mbi_mono_id   = TcId
    mono_id }]) }

    -- SPECIAL CASE 2: see Note [Inference for non-recursive pattern bindings]
    tcMonoBinds RecFlag
    is_rec TcSigFun
    sig_fn LetBndrSpec
    no_gen
               [L SrcSpanAnnA
    b_loc (PatBind { pat_lhs :: forall idL idR. HsBindLR idL idR -> LPat idL
    pat_lhs = LPat GhcRn
    pat, pat_rhs :: forall idL idR. HsBindLR idL idR -> GRHSs idR (LHsExpr idR)
    pat_rhs = GRHSs GhcRn (LHsExpr GhcRn)
    grhss })]
      | RecFlag
    NonRecursive <- RecFlag
    is_rec   -- ...binder isn't mentioned in RHS
      , (Name -> Bool) -> [Name] -> Bool
    forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
    all (Maybe TcSigInfo -> Bool
    forall a. Maybe a -> Bool
    isNothing (Maybe TcSigInfo -> Bool) -> TcSigFun -> Name -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . TcSigFun
    sig_fn) [Name]
    [IdP GhcRn]
    bndrs
      = SDoc
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    forall a. SDoc -> TcM a -> TcM a
    addErrCtxt (LPat GhcRn -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    forall (p :: Pass).
    OutputableBndrId p =>
    LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    patMonoBindsCtxt LPat GhcRn
    pat GRHSs GhcRn (LHsExpr GhcRn)
    grhss) (TcM (LHsBinds GhcTc, [MonoBindInfo])
     -> TcM (LHsBinds GhcTc, [MonoBindInfo]))
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    -> TcM (LHsBinds GhcTc, [MonoBindInfo])
    forall a b. (a -> b) -> a -> b
    $
        do { (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    grhss', Kind
    pat_ty) <- (ExpSigmaType
     -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)), Kind)
    forall a. (ExpSigmaType -> TcM a) -> TcM (a, Kind)
    tcInfer ((ExpSigmaType
      -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
     -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)), Kind))
    -> (ExpSigmaType
        -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))))
    -> TcM (GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc)), Kind)
    forall a b. (a -> b) -> a -> b
    $ \ ExpSigmaType
    exp_ty ->
                                 GRHSs GhcRn (LHsExpr GhcRn)
    -> ExpSigmaType -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    tcGRHSsPat GRHSs GhcRn (LHsExpr GhcRn)
    grhss ExpSigmaType
    exp_ty

           ; let exp_pat_ty :: Scaled ExpSigmaType
                 exp_pat_ty :: Scaled ExpSigmaType
    exp_pat_ty = ExpSigmaType -> Scaled ExpSigmaType
    forall a. a -> Scaled a
    unrestricted (Kind -> ExpSigmaType
    mkCheckExpType Kind
    pat_ty)
           ; (GenLocated SrcSpanAnnA (Pat GhcTc)
    pat', [MonoBindInfo]
    mbis) <- (Name -> Maybe TcId)
    -> LetBndrSpec
    -> LPat GhcRn
    -> Scaled ExpSigmaType
    -> TcM [MonoBindInfo]
    -> TcM (LPat GhcTc, [MonoBindInfo])
    forall a.
    (Name -> Maybe TcId)
    -> LetBndrSpec
    -> LPat GhcRn
    -> Scaled ExpSigmaType
    -> TcM a
    -> TcM (LPat GhcTc, a)
    tcLetPat (Maybe TcId -> Name -> Maybe TcId
    forall a b. a -> b -> a
    const Maybe TcId
    forall a. Maybe a
    Nothing) LetBndrSpec
    no_gen LPat GhcRn
    pat Scaled ExpSigmaType
    exp_pat_ty (TcM [MonoBindInfo] -> TcM (LPat GhcTc, [MonoBindInfo]))
    -> TcM [MonoBindInfo] -> TcM (LPat GhcTc, [MonoBindInfo])
    forall a b. (a -> b) -> a -> b
    $
                             (Name -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo)
    -> [Name] -> TcM [MonoBindInfo]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM Name -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    lookupMBI [Name]
    [IdP GhcRn]
    bndrs

           ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
     [MonoBindInfo])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
          [MonoBindInfo])
    forall (m :: * -> *) a. Monad m => a -> m a
    return ( GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. a -> Bag a
    unitBag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
     -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a b. (a -> b) -> a -> b
    $ SrcSpanAnnA
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall l e. l -> e -> GenLocated l e
    L SrcSpanAnnA
    b_loc (HsBindLR GhcTc GhcTc
     -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    -> HsBindLR GhcTc GhcTc
    -> GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
                         PatBind { pat_lhs :: LPat GhcTc
    pat_lhs = GenLocated SrcSpanAnnA (Pat GhcTc)
    LPat GhcTc
    pat', pat_rhs :: GRHSs GhcTc (LHsExpr GhcTc)
    pat_rhs = GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    GRHSs GhcTc (LHsExpr GhcTc)
    grhss'
                                 , pat_ext :: XPatBind GhcTc GhcTc
    pat_ext = Kind
    XPatBind GhcTc GhcTc
    pat_ty, pat_ticks :: ([CoreTickish], [[CoreTickish]])
    pat_ticks = ([],[]) }

                    , [MonoBindInfo]
    mbis ) }
      where
        bndrs :: [IdP GhcRn]
    bndrs = CollectFlag GhcRn -> LPat GhcRn -> [IdP GhcRn]
    forall p. CollectPass p => CollectFlag p -> LPat p -> [IdP p]
    collectPatBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders LPat GhcRn
    pat

    -- GENERAL CASE
    tcMonoBinds RecFlag
    _ TcSigFun
    sig_fn LetBndrSpec
    no_gen [LHsBind GhcRn]
    binds
      = do  { [GenLocated SrcSpanAnnA TcMonoBind]
    tc_binds <- (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
     -> IOEnv
          (Env TcGblEnv TcLclEnv) (GenLocated SrcSpanAnnA TcMonoBind))
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> IOEnv
         (Env TcGblEnv TcLclEnv) [GenLocated SrcSpanAnnA TcMonoBind]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM ((HsBindLR GhcRn GhcRn -> TcM TcMonoBind)
    -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> IOEnv
         (Env TcGblEnv TcLclEnv) (GenLocated SrcSpanAnnA TcMonoBind)
    forall a b ann.
    (a -> TcM b)
    -> GenLocated (SrcSpanAnn' ann) a
    -> TcRn (GenLocated (SrcSpanAnn' ann) b)
    wrapLocMA (TcSigFun -> LetBndrSpec -> HsBindLR GhcRn GhcRn -> TcM TcMonoBind
    tcLhs TcSigFun
    sig_fn LetBndrSpec
    no_gen)) [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    [LHsBind GhcRn]
    binds

            -- Bring the monomorphic Ids, into scope for the RHSs
            ; let mono_infos :: [MonoBindInfo]
    mono_infos = [GenLocated SrcSpanAnnA TcMonoBind] -> [MonoBindInfo]
    getMonoBindInfo [GenLocated SrcSpanAnnA TcMonoBind]
    tc_binds
                  rhs_id_env :: [(Name, TcId)]
    rhs_id_env = [ (Name
    name, TcId
    mono_id)
                               | MBI { mbi_poly_name :: MonoBindInfo -> Name
    mbi_poly_name = Name
    name
                                     , mbi_sig :: MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig       = Maybe TcIdSigInst
    mb_sig
                                     , mbi_mono_id :: MonoBindInfo -> TcId
    mbi_mono_id   = TcId
    mono_id } <- [MonoBindInfo]
    mono_infos
                               , case Maybe TcIdSigInst
    mb_sig of
                                   Just TcIdSigInst
    sig -> TcIdSigInst -> Bool
    isPartialSig TcIdSigInst
    sig
                                   Maybe TcIdSigInst
    Nothing  -> Bool
    True ]
                    -- A monomorphic binding for each term variable that lacks
                    -- a complete type sig.  (Ones with a sig are already in scope.)

            ; String -> SDoc -> TcRn ()
    traceTc String
    "tcMonoBinds" (SDoc -> TcRn ()) -> SDoc -> TcRn ()
    forall a b. (a -> b) -> a -> b
    $ [SDoc] -> SDoc
    vcat [ Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    n SDoc -> SDoc -> SDoc
    <+> TcId -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcId
    id SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (TcId -> Kind
    idType TcId
    id)
                                           | (Name
    n,TcId
    id) <- [(Name, TcId)]
    rhs_id_env]
            ; [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    binds' <- [(Name, TcId)]
    -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    forall a. [(Name, TcId)] -> TcM a -> TcM a
    tcExtendRecIds [(Name, TcId)]
    rhs_id_env (TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
     -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)])
    -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    forall a b. (a -> b) -> a -> b
    $
                        (GenLocated SrcSpanAnnA TcMonoBind
     -> IOEnv
          (Env TcGblEnv TcLclEnv)
          (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)))
    -> [GenLocated SrcSpanAnnA TcMonoBind]
    -> TcM [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM ((TcMonoBind -> TcM (HsBindLR GhcTc GhcTc))
    -> GenLocated SrcSpanAnnA TcMonoBind
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a b ann.
    (a -> TcM b)
    -> GenLocated (SrcSpanAnn' ann) a
    -> TcRn (GenLocated (SrcSpanAnn' ann) b)
    wrapLocMA TcMonoBind -> TcM (HsBindLR GhcTc GhcTc)
    tcRhs) [GenLocated SrcSpanAnnA TcMonoBind]
    tc_binds

            ; (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
     [MonoBindInfo])
    -> IOEnv
         (Env TcGblEnv TcLclEnv)
         (Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)),
          [MonoBindInfo])
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc))
    forall a. [a] -> Bag a
    listToBag [GenLocated SrcSpanAnnA (HsBindLR GhcTc GhcTc)]
    binds', [MonoBindInfo]
    mono_infos) }

    {- Note [Special case for non-recursive function bindings]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In the special case of
    * A non-recursive FunBind
    * With no type signature
    we infer the type of the right hand side first (it may have a
    higher-rank type) and *then* make the monomorphic Id for the LHS e.g.
       f = \(x::forall a. a->a) -> <body>

    We want to infer a higher-rank type for f

    Note [Special case for non-recursive pattern bindings]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In the special case of
    * A pattern binding
    * With no type signature for any of the binders
    we can /infer/ the type of the RHS, and /check/ the pattern
    against that type.  For example (#18323)

      ids :: [forall a. a -> a]
      combine :: (forall a . [a] -> a) -> [forall a. a -> a]
              -> ((forall a . [a] -> a), [forall a. a -> a])

      (x,y) = combine head ids

    with -XImpredicativeTypes we can infer a good type for
    (combine head ids), and use that to tell us the polymorphic
    types of x and y.

    We don't need to check -XImpredicativeTypes beucase without it
    these types like [forall a. a->a] are illegal anyway, so this
    special case code only really has an effect if -XImpredicativeTypes
    is on.  Small exception:
      (x) = e
    is currently treated as a pattern binding so, even absent
    -XImpredicativeTypes, we will get a small improvement in behaviour.
    But I don't think it's worth an extension flag.

    Why do we require no type signatures on /any/ of the binders?
    Consider
       x :: forall a. a->a
       y :: forall a. a->a
       (x,y) = (id,id)

    Here we should /check/ the RHS with expected type
      (forall a. a->a, forall a. a->a).

    If we have no signatures, we can the approach of this Note
    to /infer/ the type of the RHS.

    But what if we have some signatures, but not all? Say this:
      p :: forall a. a->a
      (p,q) = (id,  (\(x::forall b. b->b). x True))

    Here we want to push p's signature inwards, i.e. /checking/, to
    correctly elaborate 'id'. But we want to /infer/ q's higher rank
    type.  There seems to be no way to do this.  So currently we only
    switch to inference when we have no signature for any of the binders.
    -}

    ------------------------
    -- tcLhs typechecks the LHS of the bindings, to construct the environment in which
    -- we typecheck the RHSs.  Basically what we are doing is this: for each binder:
    --      if there's a signature for it, use the instantiated signature type
    --      otherwise invent a type variable
    -- You see that quite directly in the FunBind case.
    --
    -- But there's a complication for pattern bindings:
    --      data T = MkT (forall a. a->a)
    --      MkT f = e
    -- Here we can guess a type variable for the entire LHS (which will be refined to T)
    -- but we want to get (f::forall a. a->a) as the RHS environment.
    -- The simplest way to do this is to typecheck the pattern, and then look up the
    -- bound mono-ids.  Then we want to retain the typechecked pattern to avoid re-doing
    -- it; hence the TcMonoBind data type in which the LHS is done but the RHS isn't

    data TcMonoBind         -- Half completed; LHS done, RHS not done
      = TcFunBind  MonoBindInfo  SrcSpan (MatchGroup GhcRn (LHsExpr GhcRn))
      | TcPatBind [MonoBindInfo] (LPat GhcTc) (GRHSs GhcRn (LHsExpr GhcRn))
                  TcSigmaType

    tcLhs :: TcSigFun -> LetBndrSpec -> HsBind GhcRn -> TcM TcMonoBind
    -- Only called with plan InferGen (LetBndrSpec = LetLclBndr)
    --                    or NoGen    (LetBndrSpec = LetGblBndr)
    -- CheckGen is used only for functions with a complete type signature,
    --          and tcPolyCheck doesn't use tcMonoBinds at all

    tcLhs :: TcSigFun -> LetBndrSpec -> HsBindLR GhcRn GhcRn -> TcM TcMonoBind
    tcLhs TcSigFun
    sig_fn LetBndrSpec
    no_gen (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = L SrcSpanAnnN
    nm_loc Name
    name
                                 , fun_matches :: forall idL idR. HsBindLR idL idR -> MatchGroup idR (LHsExpr idR)
    fun_matches = MatchGroup GhcRn (LHsExpr GhcRn)
    matches })
      | Just (TcIdSig TcIdSigInfo
    sig) <- TcSigFun
    sig_fn Name
    name
      = -- There is a type signature.
        -- It must be partial; if complete we'd be in tcPolyCheck!
        --    e.g.   f :: _ -> _
        --           f x = ...g...
        --           Just g = ...f...
        -- Hence always typechecked with InferGen
        do { MonoBindInfo
    mono_info <- LetBndrSpec
    -> (Name, TcIdSigInfo)
    -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    tcLhsSigId LetBndrSpec
    no_gen (Name
    name, TcIdSigInfo
    sig)
           ; TcMonoBind -> TcM TcMonoBind
    forall (m :: * -> *) a. Monad m => a -> m a
    return (MonoBindInfo
    -> SrcSpan -> MatchGroup GhcRn (LHsExpr GhcRn) -> TcMonoBind
    TcFunBind MonoBindInfo
    mono_info (SrcSpanAnnN -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA SrcSpanAnnN
    nm_loc) MatchGroup GhcRn (LHsExpr GhcRn)
    matches) }

      | Bool
    otherwise  -- No type signature
      = do { Kind
    mono_ty <- TcM Kind
    newOpenFlexiTyVarTy
           ; TcId
    mono_id <- LetBndrSpec
    -> Name -> Kind -> Kind -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newLetBndr LetBndrSpec
    no_gen Name
    name Kind
    Many Kind
    mono_ty
              -- This ^ generates a binder with Many multiplicity because all
              -- let/where-binders are unrestricted. When we introduce linear let
              -- binders, we will need to retrieve the multiplicity information.
           ; let mono_info :: MonoBindInfo
    mono_info = MBI { mbi_poly_name :: Name
    mbi_poly_name = Name
    name
                                 , mbi_sig :: Maybe TcIdSigInst
    mbi_sig       = Maybe TcIdSigInst
    forall a. Maybe a
    Nothing
                                 , mbi_mono_id :: TcId
    mbi_mono_id   = TcId
    mono_id }
           ; TcMonoBind -> TcM TcMonoBind
    forall (m :: * -> *) a. Monad m => a -> m a
    return (MonoBindInfo
    -> SrcSpan -> MatchGroup GhcRn (LHsExpr GhcRn) -> TcMonoBind
    TcFunBind MonoBindInfo
    mono_info (SrcSpanAnnN -> SrcSpan
    forall a. SrcSpanAnn' a -> SrcSpan
    locA SrcSpanAnnN
    nm_loc) MatchGroup GhcRn (LHsExpr GhcRn)
    matches) }

    tcLhs TcSigFun
    sig_fn LetBndrSpec
    no_gen (PatBind { pat_lhs :: forall idL idR. HsBindLR idL idR -> LPat idL
    pat_lhs = LPat GhcRn
    pat, pat_rhs :: forall idL idR. HsBindLR idL idR -> GRHSs idR (LHsExpr idR)
    pat_rhs = GRHSs GhcRn (LHsExpr GhcRn)
    grhss })
      = -- See Note [Typechecking pattern bindings]
        do  { [MonoBindInfo]
    sig_mbis <- ((Name, TcIdSigInfo) -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo)
    -> [(Name, TcIdSigInfo)] -> TcM [MonoBindInfo]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM (LetBndrSpec
    -> (Name, TcIdSigInfo)
    -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    tcLhsSigId LetBndrSpec
    no_gen) [(Name, TcIdSigInfo)]
    sig_names

            ; let inst_sig_fun :: Name -> Maybe TcId
    inst_sig_fun = NameEnv TcId -> Name -> Maybe TcId
    forall a. NameEnv a -> Name -> Maybe a
    lookupNameEnv (NameEnv TcId -> Name -> Maybe TcId)
    -> NameEnv TcId -> Name -> Maybe TcId
    forall a b. (a -> b) -> a -> b
    $ [(Name, TcId)] -> NameEnv TcId
    forall a. [(Name, a)] -> NameEnv a
    mkNameEnv ([(Name, TcId)] -> NameEnv TcId) -> [(Name, TcId)] -> NameEnv TcId
    forall a b. (a -> b) -> a -> b
    $
                                 [ (MonoBindInfo -> Name
    mbi_poly_name MonoBindInfo
    mbi, MonoBindInfo -> TcId
    mbi_mono_id MonoBindInfo
    mbi)
                                 | MonoBindInfo
    mbi <- [MonoBindInfo]
    sig_mbis ]

                -- See Note [Existentials in pattern bindings]
            ; ((GenLocated SrcSpanAnnA (Pat GhcTc)
    pat', [MonoBindInfo]
    nosig_mbis), Kind
    pat_ty)
                <- SDoc
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    forall a. SDoc -> TcM a -> TcM a
    addErrCtxt (LPat GhcRn -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    forall (p :: Pass).
    OutputableBndrId p =>
    LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    patMonoBindsCtxt LPat GhcRn
    pat GRHSs GhcRn (LHsExpr GhcRn)
    grhss) (TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
     -> TcM
          ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind))
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    forall a b. (a -> b) -> a -> b
    $
                   (ExpSigmaType
     -> IOEnv
          (Env TcGblEnv TcLclEnv)
          (GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]))
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    forall a. (ExpSigmaType -> TcM a) -> TcM (a, Kind)
    tcInfer ((ExpSigmaType
      -> IOEnv
           (Env TcGblEnv TcLclEnv)
           (GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]))
     -> TcM
          ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind))
    -> (ExpSigmaType
        -> IOEnv
             (Env TcGblEnv TcLclEnv)
             (GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]))
    -> TcM ((GenLocated SrcSpanAnnA (Pat GhcTc), [MonoBindInfo]), Kind)
    forall a b. (a -> b) -> a -> b
    $ \ ExpSigmaType
    exp_ty ->
                   (Name -> Maybe TcId)
    -> LetBndrSpec
    -> LPat GhcRn
    -> Scaled ExpSigmaType
    -> TcM [MonoBindInfo]
    -> TcM (LPat GhcTc, [MonoBindInfo])
    forall a.
    (Name -> Maybe TcId)
    -> LetBndrSpec
    -> LPat GhcRn
    -> Scaled ExpSigmaType
    -> TcM a
    -> TcM (LPat GhcTc, a)
    tcLetPat Name -> Maybe TcId
    inst_sig_fun LetBndrSpec
    no_gen LPat GhcRn
    pat (ExpSigmaType -> Scaled ExpSigmaType
    forall a. a -> Scaled a
    unrestricted ExpSigmaType
    exp_ty) (TcM [MonoBindInfo] -> TcM (LPat GhcTc, [MonoBindInfo]))
    -> TcM [MonoBindInfo] -> TcM (LPat GhcTc, [MonoBindInfo])
    forall a b. (a -> b) -> a -> b
    $
                     -- The above inferred type get an unrestricted multiplicity. It may be
                     -- worth it to try and find a finer-grained multiplicity here
                     -- if examples warrant it.
                   (Name -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo)
    -> [Name] -> TcM [MonoBindInfo]
    forall (t :: * -> *) (m :: * -> *) a b.
    (Traversable t, Monad m) =>
    (a -> m b) -> t a -> m (t b)
    mapM Name -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    lookupMBI [Name]
    nosig_names

            ; let mbis :: [MonoBindInfo]
    mbis = [MonoBindInfo]
    sig_mbis [MonoBindInfo] -> [MonoBindInfo] -> [MonoBindInfo]
    forall a. [a] -> [a] -> [a]
    ++ [MonoBindInfo]
    nosig_mbis

            ; String -> SDoc -> TcRn ()
    traceTc String
    "tcLhs" ([SDoc] -> SDoc
    vcat [ TcId -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcId
    id SDoc -> SDoc -> SDoc
    <+> SDoc
    dcolon SDoc -> SDoc -> SDoc
    <+> Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (TcId -> Kind
    idType TcId
    id)
                                    | MonoBindInfo
    mbi <- [MonoBindInfo]
    mbis, let id :: TcId
    id = MonoBindInfo -> TcId
    mbi_mono_id MonoBindInfo
    mbi ]
                               SDoc -> SDoc -> SDoc
    $$ LetBndrSpec -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr LetBndrSpec
    no_gen)

            ; TcMonoBind -> TcM TcMonoBind
    forall (m :: * -> *) a. Monad m => a -> m a
    return ([MonoBindInfo]
    -> LPat GhcTc -> GRHSs GhcRn (LHsExpr GhcRn) -> Kind -> TcMonoBind
    TcPatBind [MonoBindInfo]
    mbis GenLocated SrcSpanAnnA (Pat GhcTc)
    LPat GhcTc
    pat' GRHSs GhcRn (LHsExpr GhcRn)
    grhss Kind
    pat_ty) }
      where
        bndr_names :: [IdP GhcRn]
    bndr_names = CollectFlag GhcRn -> LPat GhcRn -> [IdP GhcRn]
    forall p. CollectPass p => CollectFlag p -> LPat p -> [IdP p]
    collectPatBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders LPat GhcRn
    pat
        ([Name]
    nosig_names, [(Name, TcIdSigInfo)]
    sig_names) = (Name -> Either Name (Name, TcIdSigInfo))
    -> [Name] -> ([Name], [(Name, TcIdSigInfo)])
    forall a b c. (a -> Either b c) -> [a] -> ([b], [c])
    partitionWith Name -> Either Name (Name, TcIdSigInfo)
    find_sig [Name]
    [IdP GhcRn]
    bndr_names

        find_sig :: Name -> Either Name (Name, TcIdSigInfo)
        find_sig :: Name -> Either Name (Name, TcIdSigInfo)
    find_sig Name
    name = case TcSigFun
    sig_fn Name
    name of
                          Just (TcIdSig TcIdSigInfo
    sig) -> (Name, TcIdSigInfo) -> Either Name (Name, TcIdSigInfo)
    forall a b. b -> Either a b
    Right (Name
    name, TcIdSigInfo
    sig)
                          Maybe TcSigInfo
    _                  -> Name -> Either Name (Name, TcIdSigInfo)
    forall a b. a -> Either a b
    Left Name
    name

    tcLhs TcSigFun
    _ LetBndrSpec
    _ HsBindLR GhcRn GhcRn
    other_bind = String -> SDoc -> TcM TcMonoBind
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "tcLhs" (HsBindLR GhcRn GhcRn -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr HsBindLR GhcRn GhcRn
    other_bind)
            -- AbsBind, VarBind impossible

    lookupMBI :: Name -> TcM MonoBindInfo
    -- After typechecking the pattern, look up the binder
    -- names that lack a signature, which the pattern has brought
    -- into scope.
    lookupMBI :: Name -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    lookupMBI Name
    name
      = do { TcId
    mono_id <- Name -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    tcLookupId Name
    name
           ; MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    forall (m :: * -> *) a. Monad m => a -> m a
    return (MBI { mbi_poly_name :: Name
    mbi_poly_name = Name
    name
                         , mbi_sig :: Maybe TcIdSigInst
    mbi_sig       = Maybe TcIdSigInst
    forall a. Maybe a
    Nothing
                         , mbi_mono_id :: TcId
    mbi_mono_id   = TcId
    mono_id }) }

    -------------------
    tcLhsSigId :: LetBndrSpec -> (Name, TcIdSigInfo) -> TcM MonoBindInfo
    tcLhsSigId :: LetBndrSpec
    -> (Name, TcIdSigInfo)
    -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    tcLhsSigId LetBndrSpec
    no_gen (Name
    name, TcIdSigInfo
    sig)
      = do { TcIdSigInst
    inst_sig <- TcIdSigInfo -> TcM TcIdSigInst
    tcInstSig TcIdSigInfo
    sig
           ; TcId
    mono_id <- LetBndrSpec
    -> Name -> TcIdSigInst -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newSigLetBndr LetBndrSpec
    no_gen Name
    name TcIdSigInst
    inst_sig
           ; MonoBindInfo -> IOEnv (Env TcGblEnv TcLclEnv) MonoBindInfo
    forall (m :: * -> *) a. Monad m => a -> m a
    return (MBI { mbi_poly_name :: Name
    mbi_poly_name = Name
    name
                         , mbi_sig :: Maybe TcIdSigInst
    mbi_sig       = TcIdSigInst -> Maybe TcIdSigInst
    forall a. a -> Maybe a
    Just TcIdSigInst
    inst_sig
                         , mbi_mono_id :: TcId
    mbi_mono_id   = TcId
    mono_id }) }

    ------------
    newSigLetBndr :: LetBndrSpec -> Name -> TcIdSigInst -> TcM TcId
    newSigLetBndr :: LetBndrSpec
    -> Name -> TcIdSigInst -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newSigLetBndr (LetGblBndr TcPragEnv
    prags) Name
    name (TISI { sig_inst_sig :: TcIdSigInst -> TcIdSigInfo
    sig_inst_sig = TcIdSigInfo
    id_sig })
      | CompleteSig { sig_bndr :: TcIdSigInfo -> TcId
    sig_bndr = TcId
    poly_id } <- TcIdSigInfo
    id_sig
      = TcId -> [LSig GhcRn] -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    addInlinePrags TcId
    poly_id (TcPragEnv -> Name -> [LSig GhcRn]
    lookupPragEnv TcPragEnv
    prags Name
    name)
    newSigLetBndr LetBndrSpec
    no_gen Name
    name (TISI { sig_inst_tau :: TcIdSigInst -> Kind
    sig_inst_tau = Kind
    tau })
      = LetBndrSpec
    -> Name -> Kind -> Kind -> IOEnv (Env TcGblEnv TcLclEnv) TcId
    newLetBndr LetBndrSpec
    no_gen Name
    name Kind
    Many Kind
    tau
        -- Binders with a signature are currently always of multiplicity
        -- Many. Because they come either from toplevel, let, or where
        -- declarations. Which are all unrestricted currently.

    -------------------
    tcRhs :: TcMonoBind -> TcM (HsBind GhcTc)
    tcRhs :: TcMonoBind -> TcM (HsBindLR GhcTc GhcTc)
    tcRhs (TcFunBind info :: MonoBindInfo
    info@(MBI { mbi_sig :: MonoBindInfo -> Maybe TcIdSigInst
    mbi_sig = Maybe TcIdSigInst
    mb_sig, mbi_mono_id :: MonoBindInfo -> TcId
    mbi_mono_id = TcId
    mono_id })
                     SrcSpan
    loc MatchGroup GhcRn (LHsExpr GhcRn)
    matches)
      = [MonoBindInfo]
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a. [MonoBindInfo] -> TcM a -> TcM a
    tcExtendIdBinderStackForRhs [MonoBindInfo
    info]  (TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc))
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
        Maybe TcIdSigInst
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a. Maybe TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvForRhs Maybe TcIdSigInst
    mb_sig       (TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc))
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
        do  { String -> SDoc -> TcRn ()
    traceTc String
    "tcRhs: fun bind" (TcId -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcId
    mono_id SDoc -> SDoc -> SDoc
    $$ Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr (TcId -> Kind
    idType TcId
    mono_id))
            ; (HsWrapper
    co_fn, MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    matches') <- GenLocated SrcSpanAnnN Name
    -> MatchGroup GhcRn (LHsExpr GhcRn)
    -> ExpSigmaType
    -> TcRn (HsWrapper, MatchGroup GhcTc (LHsExpr GhcTc))
    tcMatchesFun (SrcSpanAnnN -> Name -> GenLocated SrcSpanAnnN Name
    forall l e. l -> e -> GenLocated l e
    L (SrcSpan -> SrcSpanAnnN
    forall ann. SrcSpan -> SrcAnn ann
    noAnnSrcSpan SrcSpan
    loc) (TcId -> Name
    idName TcId
    mono_id))
                                     MatchGroup GhcRn (LHsExpr GhcRn)
    matches (Kind -> ExpSigmaType
    mkCheckExpType (Kind -> ExpSigmaType) -> Kind -> ExpSigmaType
    forall a b. (a -> b) -> a -> b
    $ TcId -> Kind
    idType TcId
    mono_id)
            ; HsBindLR GhcTc GhcTc -> TcM (HsBindLR GhcTc GhcTc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ( FunBind { fun_id :: LIdP GhcTc
    fun_id = SrcSpanAnnN -> TcId -> GenLocated SrcSpanAnnN TcId
    forall l e. l -> e -> GenLocated l e
    L (SrcSpan -> SrcSpanAnnN
    forall ann. SrcSpan -> SrcAnn ann
    noAnnSrcSpan SrcSpan
    loc) TcId
    mono_id
                               , fun_matches :: MatchGroup GhcTc (LHsExpr GhcTc)
    fun_matches = MatchGroup GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    MatchGroup GhcTc (LHsExpr GhcTc)
    matches'
                               , fun_ext :: XFunBind GhcTc GhcTc
    fun_ext = XFunBind GhcTc GhcTc
    HsWrapper
    co_fn
                               , fun_tick :: [CoreTickish]
    fun_tick = [] } ) }

    tcRhs (TcPatBind [MonoBindInfo]
    infos LPat GhcTc
    pat' GRHSs GhcRn (LHsExpr GhcRn)
    grhss Kind
    pat_ty)
      = -- When we are doing pattern bindings we *don't* bring any scoped
        -- type variables into scope unlike function bindings
        -- Wny not?  They are not completely rigid.
        -- That's why we have the special case for a single FunBind in tcMonoBinds
        [MonoBindInfo]
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a. [MonoBindInfo] -> TcM a -> TcM a
    tcExtendIdBinderStackForRhs [MonoBindInfo]
    infos        (TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc))
    -> TcM (HsBindLR GhcTc GhcTc) -> TcM (HsBindLR GhcTc GhcTc)
    forall a b. (a -> b) -> a -> b
    $
        do  { String -> SDoc -> TcRn ()
    traceTc String
    "tcRhs: pat bind" (GenLocated SrcSpanAnnA (Pat GhcTc) -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr GenLocated SrcSpanAnnA (Pat GhcTc)
    LPat GhcTc
    pat' SDoc -> SDoc -> SDoc
    $$ Kind -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Kind
    pat_ty)
            ; GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    grhss' <- SDoc
    -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    forall a. SDoc -> TcM a -> TcM a
    addErrCtxt (LPat GhcTc -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    forall (p :: Pass).
    OutputableBndrId p =>
    LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    patMonoBindsCtxt LPat GhcTc
    pat' GRHSs GhcRn (LHsExpr GhcRn)
    grhss) (TcM (GRHSs GhcTc (LHsExpr GhcTc))
     -> TcM (GRHSs GhcTc (LHsExpr GhcTc)))
    -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    forall a b. (a -> b) -> a -> b
    $
                        GRHSs GhcRn (LHsExpr GhcRn)
    -> ExpSigmaType -> TcM (GRHSs GhcTc (LHsExpr GhcTc))
    tcGRHSsPat GRHSs GhcRn (LHsExpr GhcRn)
    grhss (Kind -> ExpSigmaType
    mkCheckExpType Kind
    pat_ty)
            ; HsBindLR GhcTc GhcTc -> TcM (HsBindLR GhcTc GhcTc)
    forall (m :: * -> *) a. Monad m => a -> m a
    return ( PatBind { pat_lhs :: LPat GhcTc
    pat_lhs = LPat GhcTc
    pat', pat_rhs :: GRHSs GhcTc (LHsExpr GhcTc)
    pat_rhs = GRHSs GhcTc (GenLocated SrcSpanAnnA (HsExpr GhcTc))
    GRHSs GhcTc (LHsExpr GhcTc)
    grhss'
                               , pat_ext :: XPatBind GhcTc GhcTc
    pat_ext = Kind
    XPatBind GhcTc GhcTc
    pat_ty
                               , pat_ticks :: ([CoreTickish], [[CoreTickish]])
    pat_ticks = ([],[]) } )}

    tcExtendTyVarEnvForRhs :: Maybe TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvForRhs :: forall a. Maybe TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvForRhs Maybe TcIdSigInst
    Nothing TcM a
    thing_inside
      = TcM a
    thing_inside
    tcExtendTyVarEnvForRhs (Just TcIdSigInst
    sig) TcM a
    thing_inside
      = TcIdSigInst -> TcM a -> TcM a
    forall a. TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvFromSig TcIdSigInst
    sig TcM a
    thing_inside

    tcExtendTyVarEnvFromSig :: TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvFromSig :: forall a. TcIdSigInst -> TcM a -> TcM a
    tcExtendTyVarEnvFromSig TcIdSigInst
    sig_inst TcM a
    thing_inside
      | TISI { sig_inst_skols :: TcIdSigInst -> [(Name, InvisTVBinder)]
    sig_inst_skols = [(Name, InvisTVBinder)]
    skol_prs, sig_inst_wcs :: TcIdSigInst -> [(Name, TcId)]
    sig_inst_wcs = [(Name, TcId)]
    wcs } <- TcIdSigInst
    sig_inst
      = [(Name, TcId)] -> TcM a -> TcM a
    forall a. [(Name, TcId)] -> TcM a -> TcM a
    tcExtendNameTyVarEnv [(Name, TcId)]
    wcs (TcM a -> TcM a) -> TcM a -> TcM a
    forall a b. (a -> b) -> a -> b
    $
        [(Name, TcId)] -> TcM a -> TcM a
    forall a. [(Name, TcId)] -> TcM a -> TcM a
    tcExtendNameTyVarEnv ((InvisTVBinder -> TcId)
    -> [(Name, InvisTVBinder)] -> [(Name, TcId)]
    forall b c a. (b -> c) -> [(a, b)] -> [(a, c)]
    mapSnd InvisTVBinder -> TcId
    forall tv argf. VarBndr tv argf -> tv
    binderVar [(Name, InvisTVBinder)]
    skol_prs) (TcM a -> TcM a) -> TcM a -> TcM a
    forall a b. (a -> b) -> a -> b
    $
        TcM a
    thing_inside

    tcExtendIdBinderStackForRhs :: [MonoBindInfo] -> TcM a -> TcM a
    -- See Note [Relevant bindings and the binder stack]
    tcExtendIdBinderStackForRhs :: forall a. [MonoBindInfo] -> TcM a -> TcM a
    tcExtendIdBinderStackForRhs [MonoBindInfo]
    infos TcM a
    thing_inside
      = [TcBinder] -> TcM a -> TcM a
    forall a. [TcBinder] -> TcM a -> TcM a
    tcExtendBinderStack [ TcId -> TopLevelFlag -> TcBinder
    TcIdBndr TcId
    mono_id TopLevelFlag
    NotTopLevel
                            | MBI { mbi_mono_id :: MonoBindInfo -> TcId
    mbi_mono_id = TcId
    mono_id } <- [MonoBindInfo]
    infos ]
                            TcM a
    thing_inside
        -- NotTopLevel: it's a monomorphic binding

    ---------------------
    getMonoBindInfo :: [LocatedA TcMonoBind] -> [MonoBindInfo]
    getMonoBindInfo :: [GenLocated SrcSpanAnnA TcMonoBind] -> [MonoBindInfo]
    getMonoBindInfo [GenLocated SrcSpanAnnA TcMonoBind]
    tc_binds
      = (GenLocated SrcSpanAnnA TcMonoBind
     -> [MonoBindInfo] -> [MonoBindInfo])
    -> [MonoBindInfo]
    -> [GenLocated SrcSpanAnnA TcMonoBind]
    -> [MonoBindInfo]
    forall (t :: * -> *) a b.
    Foldable t =>
    (a -> b -> b) -> b -> t a -> b
    foldr (TcMonoBind -> [MonoBindInfo] -> [MonoBindInfo]
    get_info (TcMonoBind -> [MonoBindInfo] -> [MonoBindInfo])
    -> (GenLocated SrcSpanAnnA TcMonoBind -> TcMonoBind)
    -> GenLocated SrcSpanAnnA TcMonoBind
    -> [MonoBindInfo]
    -> [MonoBindInfo]
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GenLocated SrcSpanAnnA TcMonoBind -> TcMonoBind
    forall l e. GenLocated l e -> e
    unLoc) [] [GenLocated SrcSpanAnnA TcMonoBind]
    tc_binds
      where
        get_info :: TcMonoBind -> [MonoBindInfo] -> [MonoBindInfo]
    get_info (TcFunBind MonoBindInfo
    info SrcSpan
    _ MatchGroup GhcRn (LHsExpr GhcRn)
    _)    [MonoBindInfo]
    rest = MonoBindInfo
    info MonoBindInfo -> [MonoBindInfo] -> [MonoBindInfo]
    forall a. a -> [a] -> [a]
    : [MonoBindInfo]
    rest
        get_info (TcPatBind [MonoBindInfo]
    infos LPat GhcTc
    _ GRHSs GhcRn (LHsExpr GhcRn)
    _ Kind
    _) [MonoBindInfo]
    rest = [MonoBindInfo]
    infos [MonoBindInfo] -> [MonoBindInfo] -> [MonoBindInfo]
    forall a. [a] -> [a] -> [a]
    ++ [MonoBindInfo]
    rest

    {- Note [Relevant bindings and the binder stack]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    When typecking a binding we extend the TcBinderStack for the RHS of
    the binding, with the /monomorphic/ Id.  That way, if we have, say
        f = \x -> blah
    and something goes wrong in 'blah', we get a "relevant binding"
    looking like  f :: alpha -> beta
    This applies if 'f' has a type signature too:
       f :: forall a. [a] -> [a]
       f x = True
    We can't unify True with [a], and a relevant binding is f :: [a] -> [a]
    If we had the *polymorphic* version of f in the TcBinderStack, it
    would not be reported as relevant, because its type is closed.
    (See TcErrors.relevantBindings.)

    Note [Typechecking pattern bindings]
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Look at:
       - typecheck/should_compile/ExPat
       - #12427, typecheck/should_compile/T12427{a,b}

      data T where
        MkT :: Integral a => a -> Int -> T

    and suppose t :: T.  Which of these pattern bindings are ok?

      E1. let { MkT p _ = t } in <body>

      E2. let { MkT _ q = t } in <body>

      E3. let { MkT (toInteger -> r) _ = t } in <body>

    * (E1) is clearly wrong because the existential 'a' escapes.
      What type could 'p' possibly have?

    * (E2) is fine, despite the existential pattern, because
      q::Int, and nothing escapes.

    * Even (E3) is fine.  The existential pattern binds a dictionary
      for (Integral a) which the view pattern can use to convert the
      a-valued field to an Integer, so r :: Integer.

    An easy way to see all three is to imagine the desugaring.
    For (E2) it would look like
        let q = case t of MkT _ q' -> q'
        in <body>

    We typecheck pattern bindings as follows.  First tcLhs does this:

      1. Take each type signature q :: ty, partial or complete, and
         instantiate it (with tcLhsSigId) to get a MonoBindInfo.  This
         gives us a fresh "mono_id" qm :: instantiate(ty), where qm has
         a fresh name.

         Any fresh unification variables in instantiate(ty) born here, not
         deep under implications as would happen if we allocated them when
         we encountered q during tcPat.

      2. Build a little environment mapping "q" -> "qm" for those Ids
         with signatures (inst_sig_fun)

      3. Invoke tcLetPat to typecheck the pattern.

         - We pass in the current TcLevel.  This is captured by
           GHC.Tc.Gen.Pat.tcLetPat, and put into the pc_lvl field of PatCtxt, in
           PatEnv.

         - When tcPat finds an existential constructor, it binds fresh
           type variables and dictionaries as usual, increments the TcLevel,
           and emits an implication constraint.

         - When we come to a binder (GHC.Tc.Gen.Pat.tcPatBndr), it looks it up
           in the little environment (the pc_sig_fn field of PatCtxt).

             Success => There was a type signature, so just use it,
                        checking compatibility with the expected type.

             Failure => No type signature.
                 Infer case: (happens only outside any constructor pattern)
                             use a unification variable
                             at the outer level pc_lvl

                 Check case: use promoteTcType to promote the type
                             to the outer level pc_lvl.  This is the
                             place where we emit a constraint that'll blow
                             up if existential capture takes place

           Result: the type of the binder is always at pc_lvl. This is
           crucial.

      4. Throughout, when we are making up an Id for the pattern-bound variables
         (newLetBndr), we have two cases:

         - If we are generalising (generalisation plan is InferGen or
           CheckGen), then the let_bndr_spec will be LetLclBndr.  In that case
           we want to bind a cloned, local version of the variable, with the
           type given by the pattern context, *not* by the signature (even if
           there is one; see #7268). The mkExport part of the
           generalisation step will do the checking and impedance matching
           against the signature.

         - If for some reason we are not generalising (plan = NoGen), the
           LetBndrSpec will be LetGblBndr.  In that case we must bind the
           global version of the Id, and do so with precisely the type given
           in the signature.  (Then we unify with the type from the pattern
           context type.)

    And that's it!  The implication constraints check for the skolem
    escape.  It's quite simple and neat, and more expressive than before
    e.g. GHC 8.0 rejects (E2) and (E3).

    Example for (E1), starting at level 1.  We generate
         p :: beta:1, with constraints (forall:3 a. Integral a => a ~ beta)
    The (a~beta) can't float (because of the 'a'), nor be solved (because
    beta is untouchable.)

    Example for (E2), we generate
         q :: beta:1, with constraint (forall:3 a. Integral a => Int ~ beta)
    The beta is untouchable, but floats out of the constraint and can
    be solved absolutely fine.

    ************************************************************************
    *                                                                      *
                    Generalisation
    *                                                                      *
    ********************************************************************* -}

    data GeneralisationPlan
      = NoGen               -- No generalisation, no AbsBinds

      | InferGen            -- Implicit generalisation; there is an AbsBinds
           Bool             --   True <=> apply the MR; generalise only unconstrained type vars

      | CheckGen (LHsBind GhcRn) TcIdSigInfo
                            -- One FunBind with a signature
                            -- Explicit generalisation

    -- A consequence of the no-AbsBinds choice (NoGen) is that there is
    -- no "polymorphic Id" and "monmomorphic Id"; there is just the one

    instance Outputable GeneralisationPlan where
      ppr :: GeneralisationPlan -> SDoc
    ppr GeneralisationPlan
    NoGen          = String -> SDoc
    text String
    "NoGen"
      ppr (InferGen Bool
    b)   = String -> SDoc
    text String
    "InferGen" SDoc -> SDoc -> SDoc
    <+> Bool -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Bool
    b
      ppr (CheckGen LHsBind GhcRn
    _ TcIdSigInfo
    s) = String -> SDoc
    text String
    "CheckGen" SDoc -> SDoc -> SDoc
    <+> TcIdSigInfo -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr TcIdSigInfo
    s

    decideGeneralisationPlan
       :: DynFlags -> [LHsBind GhcRn] -> IsGroupClosed -> TcSigFun
       -> GeneralisationPlan
    decideGeneralisationPlan :: DynFlags
    -> [LHsBind GhcRn]
    -> IsGroupClosed
    -> TcSigFun
    -> GeneralisationPlan
    decideGeneralisationPlan DynFlags
    dflags [LHsBind GhcRn]
    lbinds IsGroupClosed
    closed TcSigFun
    sig_fn
      | Bool
    has_partial_sigs                         = Bool -> GeneralisationPlan
    InferGen ([Bool] -> Bool
    forall (t :: * -> *). Foldable t => t Bool -> Bool
    and [Bool]
    partial_sig_mrs)
      | Just (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    bind, TcIdSigInfo
    sig) <- Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), TcIdSigInfo)
    one_funbind_with_sig = LHsBind GhcRn -> TcIdSigInfo -> GeneralisationPlan
    CheckGen GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    LHsBind GhcRn
    bind TcIdSigInfo
    sig
      | IsGroupClosed -> Bool
    do_not_generalise IsGroupClosed
    closed                 = GeneralisationPlan
    NoGen
      | Bool
    otherwise                                = Bool -> GeneralisationPlan
    InferGen Bool
    mono_restriction
      where
        binds :: [HsBindLR GhcRn GhcRn]
    binds = (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
     -> HsBindLR GhcRn GhcRn)
    -> [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    -> [HsBindLR GhcRn GhcRn]
    forall a b. (a -> b) -> [a] -> [b]
    map GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> HsBindLR GhcRn GhcRn
    forall l e. GenLocated l e -> e
    unLoc [GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)]
    [LHsBind GhcRn]
    lbinds

        partial_sig_mrs :: [Bool]
        -- One for each partial signature (so empty => no partial sigs)
        -- The Bool is True if the signature has no constraint context
        --      so we should apply the MR
        -- See Note [Partial type signatures and generalisation]
        partial_sig_mrs :: [Bool]
    partial_sig_mrs
          = [ [GenLocated SrcSpanAnnA (HsType GhcRn)] -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null ([GenLocated SrcSpanAnnA (HsType GhcRn)] -> Bool)
    -> [GenLocated SrcSpanAnnA (HsType GhcRn)] -> Bool
    forall a b. (a -> b) -> a -> b
    $ Maybe (LHsContext GhcRn) -> HsContext GhcRn
    forall (p :: Pass).
    Maybe (LHsContext (GhcPass p)) -> HsContext (GhcPass p)
    fromMaybeContext Maybe (LHsContext GhcRn)
    mtheta
            | TcIdSig (PartialSig { psig_hs_ty :: TcIdSigInfo -> LHsSigWcType GhcRn
    psig_hs_ty = LHsSigWcType GhcRn
    hs_ty })
                <- TcSigFun -> [Name] -> [TcSigInfo]
    forall a b. (a -> Maybe b) -> [a] -> [b]
    mapMaybe TcSigFun
    sig_fn (CollectFlag GhcRn -> [LHsBind GhcRn] -> [IdP GhcRn]
    forall p idR.
    CollectPass p =>
    CollectFlag p -> [LHsBindLR p idR] -> [IdP p]
    collectHsBindListBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders [LHsBind GhcRn]
    lbinds)
            , let (Maybe (LHsContext GhcRn)
    mtheta, LHsType GhcRn
    _) = LHsType GhcRn -> (Maybe (LHsContext GhcRn), LHsType GhcRn)
    forall (pass :: Pass).
    LHsType (GhcPass pass)
    -> (Maybe (LHsContext (GhcPass pass)), LHsType (GhcPass pass))
    splitLHsQualTy (LHsSigWcType GhcRn -> LHsType GhcRn
    forall p. UnXRec p => LHsSigWcType p -> LHsType p
    hsSigWcType LHsSigWcType GhcRn
    hs_ty) ]

        has_partial_sigs :: Bool
    has_partial_sigs   = Bool -> Bool
    not ([Bool] -> Bool
    forall (t :: * -> *) a. Foldable t => t a -> Bool
    null [Bool]
    partial_sig_mrs)

        mono_restriction :: Bool
    mono_restriction  = Extension -> DynFlags -> Bool
    xopt Extension
    LangExt.MonomorphismRestriction DynFlags
    dflags
                         Bool -> Bool -> Bool
    && (HsBindLR GhcRn GhcRn -> Bool) -> [HsBindLR GhcRn GhcRn] -> Bool
    forall (t :: * -> *) a. Foldable t => (a -> Bool) -> t a -> Bool
    any HsBindLR GhcRn GhcRn -> Bool
    restricted [HsBindLR GhcRn GhcRn]
    binds

        do_not_generalise :: IsGroupClosed -> Bool
    do_not_generalise (IsGroupClosed NameEnv (UniqSet Name)
    _ Bool
    True) = Bool
    False
            -- The 'True' means that all of the group's
            -- free vars have ClosedTypeId=True; so we can ignore
            -- -XMonoLocalBinds, and generalise anyway
        do_not_generalise IsGroupClosed
    _ = Extension -> DynFlags -> Bool
    xopt Extension
    LangExt.MonoLocalBinds DynFlags
    dflags

        -- With OutsideIn, all nested bindings are monomorphic
        -- except a single function binding with a signature
        one_funbind_with_sig :: Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), TcIdSigInfo)
    one_funbind_with_sig
          | [lbind :: LHsBind GhcRn
    lbind@(L SrcSpanAnnA
    _ (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = LIdP GhcRn
    v }))] <- [LHsBind GhcRn]
    lbinds
          , Just (TcIdSig TcIdSigInfo
    sig) <- TcSigFun
    sig_fn (GenLocated SrcSpanAnnN Name -> Name
    forall l e. GenLocated l e -> e
    unLoc GenLocated SrcSpanAnnN Name
    LIdP GhcRn
    v)
          = (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), TcIdSigInfo)
    -> Maybe
         (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), TcIdSigInfo)
    forall a. a -> Maybe a
    Just (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    LHsBind GhcRn
    lbind, TcIdSigInfo
    sig)
          | Bool
    otherwise
          = Maybe (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn), TcIdSigInfo)
    forall a. Maybe a
    Nothing

        -- The Haskell 98 monomorphism restriction
        restricted :: HsBindLR GhcRn GhcRn -> Bool
    restricted (PatBind {})                              = Bool
    True
        restricted (VarBind { var_id :: forall idL idR. HsBindLR idL idR -> IdP idL
    var_id = IdP GhcRn
    v })                  = Name -> Bool
    no_sig Name
    IdP GhcRn
    v
        restricted (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = LIdP GhcRn
    v, fun_matches :: forall idL idR. HsBindLR idL idR -> MatchGroup idR (LHsExpr idR)
    fun_matches = MatchGroup GhcRn (LHsExpr GhcRn)
    m }) = MatchGroup GhcRn (GenLocated SrcSpanAnnA (HsExpr GhcRn)) -> Bool
    forall {id :: Pass} {body}. MatchGroup (GhcPass id) body -> Bool
    restricted_match MatchGroup GhcRn (GenLocated SrcSpanAnnA (HsExpr GhcRn))
    MatchGroup GhcRn (LHsExpr GhcRn)
    m
                                                               Bool -> Bool -> Bool
    && Name -> Bool
    no_sig (GenLocated SrcSpanAnnN Name -> Name
    forall l e. GenLocated l e -> e
    unLoc GenLocated SrcSpanAnnN Name
    LIdP GhcRn
    v)
        restricted HsBindLR GhcRn GhcRn
    b = String -> SDoc -> Bool
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "isRestrictedGroup/unrestricted" (HsBindLR GhcRn GhcRn -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr HsBindLR GhcRn GhcRn
    b)

        restricted_match :: MatchGroup (GhcPass id) body -> Bool
    restricted_match MatchGroup (GhcPass id) body
    mg = MatchGroup (GhcPass id) body -> BKey
    forall (id :: Pass) body. MatchGroup (GhcPass id) body -> BKey
    matchGroupArity MatchGroup (GhcPass id) body
    mg BKey -> BKey -> Bool
    forall a. Eq a => a -> a -> Bool
    == BKey
    0
            -- No args => like a pattern binding
            -- Some args => a function binding

        no_sig :: Name -> Bool
    no_sig Name
    n = Bool -> Bool
    not (TcSigFun -> Name -> Bool
    hasCompleteSig TcSigFun
    sig_fn Name
    n)

    isClosedBndrGroup :: TcTypeEnv -> Bag (LHsBind GhcRn) -> IsGroupClosed
    isClosedBndrGroup :: TcTypeEnv -> LHsBinds GhcRn -> IsGroupClosed
    isClosedBndrGroup TcTypeEnv
    type_env LHsBinds GhcRn
    binds
      = NameEnv (UniqSet Name) -> Bool -> IsGroupClosed
    IsGroupClosed NameEnv (UniqSet Name)
    fv_env Bool
    type_closed
      where
        type_closed :: Bool
    type_closed = (UniqSet Name -> Bool) -> NameEnv (UniqSet Name) -> Bool
    forall elt key. (elt -> Bool) -> UniqFM key elt -> Bool
    allUFM ((Name -> Bool) -> UniqSet Name -> Bool
    nameSetAll Name -> Bool
    is_closed_type_id) NameEnv (UniqSet Name)
    fv_env

        fv_env :: NameEnv NameSet
        fv_env :: NameEnv (UniqSet Name)
    fv_env = [(Name, UniqSet Name)] -> NameEnv (UniqSet Name)
    forall a. [(Name, a)] -> NameEnv a
    mkNameEnv ([(Name, UniqSet Name)] -> NameEnv (UniqSet Name))
    -> [(Name, UniqSet Name)] -> NameEnv (UniqSet Name)
    forall a b. (a -> b) -> a -> b
    $ (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
     -> [(Name, UniqSet Name)])
    -> Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    -> [(Name, UniqSet Name)]
    forall (t :: * -> *) a b. Foldable t => (a -> [b]) -> t a -> [b]
    concatMap (HsBindLR GhcRn GhcRn -> [(Name, UniqSet Name)]
    bindFvs (HsBindLR GhcRn GhcRn -> [(Name, UniqSet Name)])
    -> (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
        -> HsBindLR GhcRn GhcRn)
    -> GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> [(Name, UniqSet Name)]
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn)
    -> HsBindLR GhcRn GhcRn
    forall l e. GenLocated l e -> e
    unLoc) Bag (GenLocated SrcSpanAnnA (HsBindLR GhcRn GhcRn))
    LHsBinds GhcRn
    binds

        bindFvs :: HsBindLR GhcRn GhcRn -> [(Name, NameSet)]
        bindFvs :: HsBindLR GhcRn GhcRn -> [(Name, UniqSet Name)]
    bindFvs (FunBind { fun_id :: forall idL idR. HsBindLR idL idR -> LIdP idL
    fun_id = L SrcSpanAnnN
    _ Name
    f
                         , fun_ext :: forall idL idR. HsBindLR idL idR -> XFunBind idL idR
    fun_ext = XFunBind GhcRn GhcRn
    fvs })
           = let open_fvs :: UniqSet Name
    open_fvs = UniqSet Name -> UniqSet Name
    get_open_fvs UniqSet Name
    XFunBind GhcRn GhcRn
    fvs
             in [(Name
    f, UniqSet Name
    open_fvs)]
        bindFvs (PatBind { pat_lhs :: forall idL idR. HsBindLR idL idR -> LPat idL
    pat_lhs = LPat GhcRn
    pat, pat_ext :: forall idL idR. HsBindLR idL idR -> XPatBind idL idR
    pat_ext = XPatBind GhcRn GhcRn
    fvs })
           = let open_fvs :: UniqSet Name
    open_fvs = UniqSet Name -> UniqSet Name
    get_open_fvs UniqSet Name
    XPatBind GhcRn GhcRn
    fvs
             in [(Name
    b, UniqSet Name
    open_fvs) | Name
    b <- CollectFlag GhcRn -> LPat GhcRn -> [IdP GhcRn]
    forall p. CollectPass p => CollectFlag p -> LPat p -> [IdP p]
    collectPatBinders CollectFlag GhcRn
    forall p. CollectFlag p
    CollNoDictBinders LPat GhcRn
    pat]
        bindFvs HsBindLR GhcRn GhcRn
    _
           = []

        get_open_fvs :: UniqSet Name -> UniqSet Name
    get_open_fvs UniqSet Name
    fvs = (Name -> Bool) -> UniqSet Name -> UniqSet Name
    filterNameSet (Bool -> Bool
    not (Bool -> Bool) -> (Name -> Bool) -> Name -> Bool
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . Name -> Bool
    is_closed) UniqSet Name
    fvs

        is_closed :: Name -> ClosedTypeId
        is_closed :: Name -> Bool
    is_closed Name
    name
          | Just TcTyThing
    thing <- TcTypeEnv -> Name -> Maybe TcTyThing
    forall a. NameEnv a -> Name -> Maybe a
    lookupNameEnv TcTypeEnv
    type_env Name
    name
          = case TcTyThing
    thing of
              AGlobal {}                     -> Bool
    True
              ATcId { tct_info :: TcTyThing -> IdBindingInfo
    tct_info = IdBindingInfo
    ClosedLet } -> Bool
    True
              TcTyThing
    _                              -> Bool
    False

          | Bool
    otherwise
          = Bool
    True  -- The free-var set for a top level binding mentions

        is_closed_type_id :: Name -> Bool
        -- We're already removed Global and ClosedLet Ids
        is_closed_type_id :: Name -> Bool
    is_closed_type_id Name
    name
          | Just TcTyThing
    thing <- TcTypeEnv -> Name -> Maybe TcTyThing
    forall a. NameEnv a -> Name -> Maybe a
    lookupNameEnv TcTypeEnv
    type_env Name
    name
          = case TcTyThing
    thing of
              ATcId { tct_info :: TcTyThing -> IdBindingInfo
    tct_info = NonClosedLet UniqSet Name
    _ Bool
    cl } -> Bool
    cl
              ATcId { tct_info :: TcTyThing -> IdBindingInfo
    tct_info = IdBindingInfo
    NotLetBound }       -> Bool
    False
              ATyVar {}                              -> Bool
    False
                   -- In-scope type variables are not closed!
              TcTyThing
    _ -> String -> SDoc -> Bool
    forall a. HasCallStack => String -> SDoc -> a
    pprPanic String
    "is_closed_id" (Name -> SDoc
    forall a. Outputable a => a -> SDoc
    ppr Name
    name)

          | Bool
    otherwise
          = Bool
    True   -- The free-var set for a top level binding mentions
                   -- imported things too, so that we can report unused imports
                   -- These won't be in the local type env.
                   -- Ditto class method etc from the current module

    {- *********************************************************************
    *                                                                      *
                   Error contexts and messages
    *                                                                      *
    ********************************************************************* -}

    -- This one is called on LHS, when pat and grhss are both Name
    -- and on RHS, when pat is TcId and grhss is still Name
    patMonoBindsCtxt :: (OutputableBndrId p)
                     => LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    patMonoBindsCtxt :: forall (p :: Pass).
    OutputableBndrId p =>
    LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    patMonoBindsCtxt LPat (GhcPass p)
    pat GRHSs GhcRn (LHsExpr GhcRn)
    grhss
      = SDoc -> BKey -> SDoc -> SDoc
    hang (String -> SDoc
    text String
    "In a pattern binding:") BKey
    2 (LPat (GhcPass p) -> GRHSs GhcRn (LHsExpr GhcRn) -> SDoc
    forall (bndr :: Pass) (p :: Pass).
    (OutputableBndrId bndr, OutputableBndrId p) =>
    LPat (GhcPass bndr)
    -> GRHSs (GhcPass p) (LHsExpr (GhcPass p)) -> SDoc
    pprPatBind LPat (GhcPass p)
    pat GRHSs GhcRn (LHsExpr GhcRn)
    grhss)