Adapt to HsOuterTyVarBndrs

These changes accompany ghc/ghc!4107, which aims to be a fix
for #16762.

3 files changed, 139 insertions, 82 deletions

diff --git a/haddock-api/src/Haddock/Backends/Hoogle.hs b/haddock-api/src/Haddock/Backends/Hoogle.hs
index 8939664d..44841bc5 100644
--- a/haddock-api/src/Haddock/Backends/Hoogle.hs
+++ b/haddock-api/src/Haddock/Backends/Hoogle.hs
@@ -71,27 +71,31 @@ ppModule dflags iface =
 ---------------------------------------------------------------------
 -- Utility functions
 
-dropHsDocTy :: HsType (GhcPass p) -> HsType (GhcPass p)
-dropHsDocTy = f
+dropHsDocTy :: HsSigType (GhcPass p) -> HsSigType (GhcPass p)
+dropHsDocTy = drop_sig_ty
     where
-        g (L src x) = L src (f x)
-        f (HsForAllTy x a e) = HsForAllTy x a (g e)
-        f (HsQualTy x a e) = HsQualTy x a (g e)
-        f (HsBangTy x a b) = HsBangTy x a (g b)
-        f (HsAppTy x a b) = HsAppTy x (g a) (g b)
-        f (HsAppKindTy x a b) = HsAppKindTy x (g a) (g b)
-        f (HsFunTy x w a b) = HsFunTy x w (g a) (g b)
-        f (HsListTy x a) = HsListTy x (g a)
-        f (HsTupleTy x a b) = HsTupleTy x a (map g b)
-        f (HsOpTy x a b c) = HsOpTy x (g a) b (g c)
-        f (HsParTy x a) = HsParTy x (g a)
-        f (HsKindSig x a b) = HsKindSig x (g a) b
-        f (HsDocTy _ a _) = f $ unL a
-        f x = x
-
-outHsType :: (OutputableBndrId p)
-          => DynFlags -> HsType (GhcPass p) -> String
-outHsType dflags = out dflags . reparenType . dropHsDocTy
+        drop_sig_ty (HsSig x a b)  = HsSig x a (drop_lty b)
+        drop_sig_ty x@XHsSigType{} = x
+
+        drop_lty (L src x) = L src (drop_ty x)
+
+        drop_ty (HsForAllTy x a e) = HsForAllTy x a (drop_lty e)
+        drop_ty (HsQualTy x a e) = HsQualTy x a (drop_lty e)
+        drop_ty (HsBangTy x a b) = HsBangTy x a (drop_lty b)
+        drop_ty (HsAppTy x a b) = HsAppTy x (drop_lty a) (drop_lty b)
+        drop_ty (HsAppKindTy x a b) = HsAppKindTy x (drop_lty a) (drop_lty b)
+        drop_ty (HsFunTy x w a b) = HsFunTy x w (drop_lty a) (drop_lty b)
+        drop_ty (HsListTy x a) = HsListTy x (drop_lty a)
+        drop_ty (HsTupleTy x a b) = HsTupleTy x a (map drop_lty b)
+        drop_ty (HsOpTy x a b c) = HsOpTy x (drop_lty a) b (drop_lty c)
+        drop_ty (HsParTy x a) = HsParTy x (drop_lty a)
+        drop_ty (HsKindSig x a b) = HsKindSig x (drop_lty a) b
+        drop_ty (HsDocTy _ a _) = drop_ty $ unL a
+        drop_ty x = x
+
+outHsSigType :: (OutputableBndrId p, NoGhcTcPass p ~ p)
+             => DynFlags -> HsSigType (GhcPass p) -> String
+outHsSigType dflags = out dflags . reparenSigType . dropHsDocTy
 
 
 dropComment :: String -> String
@@ -135,8 +139,8 @@ ppExport dflags ExportDecl { expItemDecl    = L _ decl
         f (TyClD _ d@SynDecl{})   = ppSynonym dflags d
         f (TyClD _ d@ClassDecl{}) = ppClass dflags d subdocs
         f (TyClD _ (FamDecl _ d)) = ppFam dflags d
-        f (ForD _ (ForeignImport _ name typ _)) = [pp_sig dflags [name] (hsSigType typ)]
-        f (ForD _ (ForeignExport _ name typ _)) = [pp_sig dflags [name] (hsSigType typ)]
+        f (ForD _ (ForeignImport _ name typ _)) = [pp_sig dflags [name] typ]
+        f (ForD _ (ForeignExport _ name typ _)) = [pp_sig dflags [name] typ]
         f (SigD _ sig) = ppSig dflags sig
         f _ = []
 
@@ -145,8 +149,8 @@ ppExport _ _ = []
 
 ppSigWithDoc :: DynFlags -> Sig GhcRn -> [(Name, DocForDecl Name)] -> [String]
 ppSigWithDoc dflags sig subdocs = case sig of
-    TypeSig _ names t -> concatMap (mkDocSig "" (hsSigWcType t)) names
-    PatSynSig _ names t -> concatMap (mkDocSig "pattern " (hsSigType t)) names
+    TypeSig _ names t -> concatMap (mkDocSig "" (dropWildCards t)) names
+    PatSynSig _ names t -> concatMap (mkDocSig "pattern " t) names
     _ -> []
   where
     mkDocSig leader typ n = mkSubdoc dflags n subdocs
@@ -155,9 +159,9 @@ ppSigWithDoc dflags sig subdocs = case sig of
 ppSig :: DynFlags -> Sig GhcRn -> [String]
 ppSig dflags x  = ppSigWithDoc dflags x []
 
-pp_sig :: DynFlags -> [Located Name] -> LHsType GhcRn -> String
+pp_sig :: DynFlags -> [Located Name] -> LHsSigType GhcRn -> String
 pp_sig dflags names (L _ typ)  =
-    operator prettyNames ++ " :: " ++ outHsType dflags typ
+    operator prettyNames ++ " :: " ++ outHsSigType dflags typ
     where
       prettyNames = intercalate ", " $ map (out dflags) names
 
@@ -250,7 +254,8 @@ ppCtor dflags dat subdocs con@ConDeclH98 { con_args = con_args' }
         funs = foldr1 (\x y -> reL $ HsFunTy noExtField (HsUnrestrictedArrow NormalSyntax) x y)
         apps = foldl1 (\x y -> reL $ HsAppTy noExtField x y)
 
-        typeSig nm flds = operator nm ++ " :: " ++ outHsType dflags (unL $ funs flds)
+        typeSig nm flds = operator nm ++ " :: " ++
+                          outHsSigType dflags (unL $ mkEmptySigType $ funs flds)
 
         -- We print the constructors as comma-separated list. See GHC
         -- docs for con_names on why it is a list to begin with.
@@ -269,7 +274,7 @@ ppCtor dflags _dat subdocs con@(ConDeclGADT { })
     where
         f = [typeSig name (getGADTConTypeG con)]
 
-        typeSig nm ty = operator nm ++ " :: " ++ outHsType dflags (unL ty)
+        typeSig nm ty = operator nm ++ " :: " ++ outHsSigType dflags (unL ty)
         name = out dflags $ map unL $ getConNames con
 
 ppFixity :: DynFlags -> (Name, Fixity) -> [String]
diff --git a/haddock-api/src/Haddock/Backends/LaTeX.hs b/haddock-api/src/Haddock/Backends/LaTeX.hs
index d0528322..3a774ace 100644
--- a/haddock-api/src/Haddock/Backends/LaTeX.hs
+++ b/haddock-api/src/Haddock/Backends/LaTeX.hs
@@ -210,10 +210,10 @@ processExports (e : es) =
   processExport e $$ processExports es
 
 
-isSimpleSig :: ExportItem DocNameI -> Maybe ([DocName], HsType DocNameI)
+isSimpleSig :: ExportItem DocNameI -> Maybe ([DocName], HsSigType DocNameI)
 isSimpleSig ExportDecl { expItemDecl = L _ (SigD _ (TypeSig _ lnames t))
                        , expItemMbDoc = (Documentation Nothing Nothing, argDocs) }
-  | Map.null argDocs = Just (map unLoc lnames, unLoc (hsSigWcType t))
+  | Map.null argDocs = Just (map unLoc lnames, unLoc (dropWildCards t))
 isSimpleSig _ = Nothing
 
 
@@ -296,7 +296,7 @@ ppDecl decl pats (doc, fnArgsDoc) instances subdocs _fxts = case unLoc decl of
 --    | Just _  <- tcdTyPats d    -> ppTyInst False loc doc d unicode
 -- Family instances happen via FamInst now
   TyClD _ d@ClassDecl{}          -> ppClassDecl instances doc subdocs d unicode
-  SigD _ (TypeSig _ lnames ty)   -> ppFunSig (doc, fnArgsDoc) (map unLoc lnames) (hsSigWcType ty) unicode
+  SigD _ (TypeSig _ lnames ty)   -> ppFunSig (doc, fnArgsDoc) (map unLoc lnames) (dropWildCards ty) unicode
   SigD _ (PatSynSig _ lnames ty) -> ppLPatSig (doc, fnArgsDoc) (map unLoc lnames) ty unicode
   ForD _ d                       -> ppFor (doc, fnArgsDoc) d unicode
   InstD _ _                      -> empty
@@ -308,7 +308,7 @@ ppDecl decl pats (doc, fnArgsDoc) instances subdocs _fxts = case unLoc decl of
 
 ppFor :: DocForDecl DocName -> ForeignDecl DocNameI -> Bool -> LaTeX
 ppFor doc (ForeignImport _ (L _ name) typ _) unicode =
-  ppFunSig doc [name] (hsSigTypeI typ) unicode
+  ppFunSig doc [name] typ unicode
 ppFor _ _ _ = error "ppFor error in Haddock.Backends.LaTeX"
 --  error "foreign declarations are currently not supported by --latex"
 
@@ -343,9 +343,9 @@ ppFamDecl doc instances decl unicode =
 
     -- Individual equations of a closed type family
     ppFamDeclEqn :: TyFamInstEqn DocNameI -> LaTeX
-    ppFamDeclEqn (HsIB { hsib_body = FamEqn { feqn_tycon = L _ n
-                                            , feqn_rhs = rhs
-                                            , feqn_pats = ts } })
+    ppFamDeclEqn (FamEqn { feqn_tycon = L _ n
+                         , feqn_rhs = rhs
+                         , feqn_pats = ts })
       = hsep [ ppAppNameTypeArgs n ts unicode
              , equals
              , ppType unicode (unLoc rhs)
@@ -396,7 +396,7 @@ ppTySyn :: DocForDecl DocName -> TyClDecl DocNameI -> Bool -> LaTeX
 
 ppTySyn doc (SynDecl { tcdLName = L _ name, tcdTyVars = ltyvars
                          , tcdRhs = ltype }) unicode
-  = ppTypeOrFunSig (unLoc ltype) doc (full, hdr, char '=') unicode
+  = ppTypeOrFunSig (mkHsImplicitSigTypeI ltype) doc (full, hdr, char '=') unicode
   where
     hdr  = hsep (keyword "type"
                  : ppDocBinder name
@@ -411,7 +411,7 @@ ppTySyn _ _ _ = error "declaration not supported by ppTySyn"
 -------------------------------------------------------------------------------
 
 
-ppFunSig :: DocForDecl DocName -> [DocName] -> LHsType DocNameI
+ppFunSig :: DocForDecl DocName -> [DocName] -> LHsSigType DocNameI
          -> Bool -> LaTeX
 ppFunSig doc docnames (L _ typ) unicode =
   ppTypeOrFunSig typ doc
@@ -437,12 +437,12 @@ ppLPatSig doc docnames ty unicode
       )
       unicode
   where
-    typ = unLoc (hsSigTypeI ty)
+    typ = unLoc ty
     names = map getName docnames
 
 -- | Pretty-print a type, adding documentation to the whole type and its
 -- arguments as needed.
-ppTypeOrFunSig :: HsType DocNameI
+ppTypeOrFunSig :: HsSigType DocNameI
                -> DocForDecl DocName  -- ^ documentation
                -> ( LaTeX             --   first-line (no-argument docs only)
                   , LaTeX             --   first-line (argument docs only)
@@ -462,13 +462,24 @@ ppTypeOrFunSig typ (doc, argDocs) (pref1, pref2, sep0) unicode
 -- to the arguments. The output is a list of (leader/seperator, argument and
 -- its doc)
 ppSubSigLike :: Bool                  -- ^ unicode
-             -> HsType DocNameI       -- ^ type signature
+             -> HsSigType DocNameI    -- ^ type signature
              -> FnArgsDoc DocName     -- ^ docs to add
              -> [(DocName, DocForDecl DocName)] -- ^ all subdocs (useful when we have `HsRecTy`)
              -> LaTeX                 -- ^ seperator (beginning of first line)
              -> [(LaTeX, LaTeX)]      -- ^ arguments (leader/sep, type)
-ppSubSigLike unicode typ argDocs subdocs leader = do_args 0 leader typ
+ppSubSigLike unicode typ argDocs subdocs leader = do_sig_args 0 leader typ
   where
+    do_sig_args :: Int -> LaTeX -> HsSigType DocNameI -> [(LaTeX, LaTeX)]
+    do_sig_args n leader (HsSig { sig_bndrs = outer_bndrs, sig_body = ltype }) =
+      case outer_bndrs of
+        HsOuterExplicit{hso_bndrs = bndrs} ->
+          [ ( decltt leader
+            , decltt (ppHsForAllTelescope (mkHsForAllInvisTeleI bndrs) unicode)
+                <+> ppLType unicode ltype
+            ) ]
+        HsOuterImplicit{} -> do_largs n leader ltype
+
+    do_largs :: Int -> LaTeX -> LHsType DocNameI -> [(LaTeX, LaTeX)]
     do_largs n leader (L _ t) = do_args n leader t
 
     arg_doc n = rDoc . fmap _doc $ Map.lookup n argDocs
@@ -505,12 +516,16 @@ ppSubSigLike unicode typ argDocs subdocs leader = do_args 0 leader typ
     gadtOpen = text "\\{"
 
 
-ppTypeSig :: [Name] -> HsType DocNameI  -> Bool -> LaTeX
+ppTypeSig :: [Name] -> HsSigType DocNameI  -> Bool -> LaTeX
 ppTypeSig nms ty unicode =
   hsep (punctuate comma $ map ppSymName nms)
     <+> dcolon unicode
-    <+> ppType unicode ty
+    <+> ppSigType unicode ty
 
+ppHsOuterTyVarBndrs :: HsOuterTyVarBndrs flag DocNameI -> Bool -> LaTeX
+ppHsOuterTyVarBndrs (HsOuterImplicit{}) _ = empty
+ppHsOuterTyVarBndrs (HsOuterExplicit{hso_bndrs = bndrs}) unicode =
+    hsep (forallSymbol unicode : ppTyVars bndrs) <> dot
 
 ppHsForAllTelescope :: HsForAllTelescope DocNameI -> Bool -> LaTeX
 ppHsForAllTelescope tele unicode = case tele of
@@ -617,7 +632,7 @@ ppClassDecl instances doc subdocs
 
     methodTable =
       text "\\haddockpremethods{}" <> emph (text "Methods") $$
-      vcat  [ ppFunSig doc names (hsSigWcType typ) unicode
+      vcat  [ ppFunSig doc names (dropWildCards typ) unicode
             | L _ (TypeSig _ lnames typ) <- lsigs
             , let doc = lookupAnySubdoc (head names) subdocs
                   names = map unLoc lnames ]
@@ -793,7 +808,7 @@ ppSideBySideConstr subdocs unicode leader (L _ con) =
         | otherwise -> hsep [ ppOcc
                             , dcolon unicode
                             -- ++AZ++ make this prepend "{..}" when it is a record style GADT
-                            , ppLType unicode (getGADTConType con)
+                            , ppLSigType unicode (getGADTConType con)
                             ]
 
     fieldPart = case con of
@@ -868,18 +883,16 @@ ppSideBySidePat lnames typ (doc, argDocs) unicode =
          | otherwise = hsep [ keyword "pattern"
                             , ppOcc
                             , dcolon unicode
-                            , ppLType unicode (hsSigTypeI typ)
+                            , ppLSigType unicode typ
                             ]
 
     fieldPart
       | not hasArgDocs = empty
       | otherwise = vcat
           [ empty <-> text "\\qquad" <+> l <+> text "\\enspace" <+> r
-          | (l,r) <- ppSubSigLike unicode (unLoc patTy) argDocs [] (dcolon unicode)
+          | (l,r) <- ppSubSigLike unicode (unLoc typ) argDocs [] (dcolon unicode)
           ]
 
-    patTy = hsSigTypeI typ
-
     mDoc = fmap _doc $ combineDocumentation doc
 
 
@@ -1000,12 +1013,18 @@ ppLType       unicode y = ppType unicode (unLoc y)
 ppLParendType unicode y = ppParendType unicode (unLoc y)
 ppLFunLhType  unicode y = ppFunLhType unicode (unLoc y)
 
+ppLSigType :: Bool -> LHsSigType DocNameI -> LaTeX
+ppLSigType unicode y = ppSigType unicode (unLoc y)
+
 ppType, ppParendType, ppFunLhType, ppCtxType :: Bool -> HsType DocNameI -> LaTeX
 ppType       unicode ty = ppr_mono_ty (reparenTypePrec PREC_TOP ty) unicode
 ppParendType unicode ty = ppr_mono_ty (reparenTypePrec PREC_TOP ty) unicode
 ppFunLhType  unicode ty = ppr_mono_ty (reparenTypePrec PREC_FUN ty) unicode
 ppCtxType    unicode ty = ppr_mono_ty (reparenTypePrec PREC_CTX ty) unicode
 
+ppSigType :: Bool -> HsSigType DocNameI -> LaTeX
+ppSigType unicode sig_ty = ppr_sig_ty (reparenSigType sig_ty) unicode
+
 ppLHsTypeArg :: Bool -> LHsTypeArg DocNameI -> LaTeX
 ppLHsTypeArg unicode (HsValArg ty) = ppLParendType unicode ty
 ppLHsTypeArg unicode (HsTypeArg _ ki) = atSign unicode <>
@@ -1038,6 +1057,11 @@ ppKind unicode ki = ppr_mono_ty (reparenTypePrec PREC_TOP ki) unicode
 -- Drop top-level for-all type variables in user style
 -- since they are implicit in Haskell
 
+ppr_sig_ty :: HsSigType DocNameI -> Bool -> LaTeX
+ppr_sig_ty (HsSig { sig_bndrs = outer_bndrs, sig_body = ltype }) unicode
+  = sep [ ppHsOuterTyVarBndrs outer_bndrs unicode
+        , ppr_mono_lty ltype unicode ]
+
 ppr_mono_lty :: LHsType DocNameI -> Bool -> LaTeX
 ppr_mono_lty ty unicode = ppr_mono_ty (unLoc ty) unicode
 
diff --git a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
index d80f8e95..8b9739f1 100644
--- a/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
+++ b/haddock-api/src/Haddock/Backends/Xhtml/Decl.hs
@@ -62,9 +62,9 @@ ppDecl summ links (L loc decl) pats (mbDoc, fnArgsDoc) instances fixities subdoc
   TyClD _ d@(SynDecl {})         -> ppTySyn summ links fixities loc (mbDoc, fnArgsDoc) d splice unicode pkg qual
   TyClD _ d@(ClassDecl {})       -> ppClassDecl summ links instances fixities loc mbDoc subdocs d splice unicode pkg qual
   SigD _ (TypeSig _ lnames lty)  -> ppLFunSig summ links loc (mbDoc, fnArgsDoc) lnames
-                                         (hsSigWcType lty) fixities splice unicode pkg qual
+                                         (dropWildCards lty) fixities splice unicode pkg qual
   SigD _ (PatSynSig _ lnames lty) -> ppLPatSig summ links loc (mbDoc, fnArgsDoc) lnames
-                                         (hsSigTypeI lty) fixities splice unicode pkg qual
+                                         lty fixities splice unicode pkg qual
   ForD _ d                       -> ppFor summ links loc (mbDoc, fnArgsDoc) d fixities splice unicode pkg qual
   InstD _ _                      -> noHtml
   DerivD _ _                     -> noHtml
@@ -72,25 +72,25 @@ ppDecl summ links (L loc decl) pats (mbDoc, fnArgsDoc) instances fixities subdoc
 
 
 ppLFunSig :: Bool -> LinksInfo -> SrcSpan -> DocForDecl DocName ->
-             [Located DocName] -> LHsType DocNameI -> [(DocName, Fixity)] ->
+             [Located DocName] -> LHsSigType DocNameI -> [(DocName, Fixity)] ->
              Splice -> Unicode -> Maybe Package -> Qualification -> Html
 ppLFunSig summary links loc doc lnames lty fixities splice unicode pkg qual =
   ppFunSig summary links loc doc (map unLoc lnames) lty fixities
            splice unicode pkg qual
 
 ppFunSig :: Bool -> LinksInfo -> SrcSpan -> DocForDecl DocName ->
-            [DocName] -> LHsType DocNameI -> [(DocName, Fixity)] ->
+            [DocName] -> LHsSigType DocNameI -> [(DocName, Fixity)] ->
             Splice -> Unicode -> Maybe Package -> Qualification -> Html
 ppFunSig summary links loc doc docnames typ fixities splice unicode pkg qual =
   ppSigLike summary links loc mempty doc docnames fixities (unLoc typ, pp_typ)
             splice unicode pkg qual HideEmptyContexts
   where
-    pp_typ = ppLType unicode qual HideEmptyContexts typ
+    pp_typ = ppLSigType unicode qual HideEmptyContexts typ
 
 -- | Pretty print a pattern synonym
 ppLPatSig :: Bool -> LinksInfo -> SrcSpan -> DocForDecl DocName
           -> [Located DocName]     -- ^ names of patterns in declaration
-          -> LHsType DocNameI      -- ^ type of patterns in declaration
+          -> LHsSigType DocNameI   -- ^ type of patterns in declaration
           -> [(DocName, Fixity)]
           -> Splice -> Unicode -> Maybe Package -> Qualification -> Html
 ppLPatSig summary links loc doc lnames typ fixities splice unicode pkg qual =
@@ -101,7 +101,7 @@ ppLPatSig summary links loc doc lnames typ fixities splice unicode pkg qual =
 
 
 ppSigLike :: Bool -> LinksInfo -> SrcSpan -> Html -> DocForDecl DocName ->
-             [DocName] -> [(DocName, Fixity)] -> (HsType DocNameI, Html) ->
+             [DocName] -> [(DocName, Fixity)] -> (HsSigType DocNameI, Html) ->
              Splice -> Unicode -> Maybe Package -> Qualification -> HideEmptyContexts -> Html
 ppSigLike summary links loc leader doc docnames fixities (typ, pp_typ)
           splice unicode pkg qual emptyCtxts =
@@ -118,7 +118,7 @@ ppSigLike summary links loc leader doc docnames fixities (typ, pp_typ)
       | otherwise = html <+> ppFixities fixities qual
 
 
-ppTypeOrFunSig :: Bool -> LinksInfo -> SrcSpan -> [DocName] -> HsType DocNameI
+ppTypeOrFunSig :: Bool -> LinksInfo -> SrcSpan -> [DocName] -> HsSigType DocNameI
                -> DocForDecl DocName -> (Html, Html, Html)
                -> Splice -> Unicode -> Maybe Package -> Qualification
                -> HideEmptyContexts -> Html
@@ -139,15 +139,24 @@ ppTypeOrFunSig summary links loc docnames typ (doc, argDocs) (pref1, pref2, sep)
 -- If one passes in a list of the available subdocs, any top-level `HsRecTy`
 -- found will be expanded out into their fields.
 ppSubSigLike :: Unicode -> Qualification
-             -> HsType DocNameI                  -- ^ type signature
+             -> HsSigType DocNameI               -- ^ type signature
              -> FnArgsDoc DocName                -- ^ docs to add
              -> [(DocName, DocForDecl DocName)]  -- ^ all subdocs (useful when
                                                  -- we expand an `HsRecTy`)
              -> Html -> HideEmptyContexts -> [SubDecl]
-ppSubSigLike unicode qual typ argDocs subdocs sep emptyCtxts = do_args 0 sep typ
+ppSubSigLike unicode qual typ argDocs subdocs sep emptyCtxts = do_sig_args 0 sep typ
   where
+    do_sig_args :: Int -> Html -> HsSigType DocNameI -> [SubDecl]
+    do_sig_args n leader (HsSig { sig_bndrs = outer_bndrs, sig_body = ltype }) =
+      case outer_bndrs of
+        HsOuterExplicit{hso_bndrs = bndrs} -> do_largs n (leader' bndrs) ltype
+        HsOuterImplicit{}                  -> do_largs n leader          ltype
+      where
+        leader' bndrs = leader <+> ppForAll (mkHsForAllInvisTeleI bndrs) unicode qual
+
     argDoc n = Map.lookup n argDocs
 
+    do_largs :: Int -> Html -> LHsType DocNameI -> [SubDecl]
     do_largs n leader (L _ t) = do_args n leader t
 
     do_args :: Int -> Html -> HsType DocNameI -> [SubDecl]
@@ -239,7 +248,7 @@ ppFor :: Bool -> LinksInfo -> SrcSpan -> DocForDecl DocName
       -> Splice -> Unicode -> Maybe Package -> Qualification -> Html
 ppFor summary links loc doc (ForeignImport _ (L _ name) typ _) fixities
       splice unicode pkg qual
-  = ppFunSig summary links loc doc [name] (hsSigTypeI typ) fixities splice unicode pkg qual
+  = ppFunSig summary links loc doc [name] typ fixities splice unicode pkg qual
 ppFor _ _ _ _ _ _ _ _ _ _ = error "ppFor"
 
 
@@ -250,13 +259,14 @@ ppTySyn :: Bool -> LinksInfo -> [(DocName, Fixity)] -> SrcSpan
 ppTySyn summary links fixities loc doc (SynDecl { tcdLName = L _ name, tcdTyVars = ltyvars
                                                 , tcdRhs = ltype })
         splice unicode pkg qual
-  = ppTypeOrFunSig summary links loc [name] (unLoc ltype) doc
+  = ppTypeOrFunSig summary links loc [name] sig_type doc
                    (full <+> fixs, hdr <+> fixs, spaceHtml +++ equals)
                    splice unicode pkg qual ShowEmptyToplevelContexts
   where
+    sig_type = mkHsImplicitSigTypeI ltype
     hdr  = hsep ([keyword "type", ppBinder summary occ]
                  ++ ppTyVars unicode qual (hsQTvExplicit ltyvars))
-    full = hdr <+> equals <+> ppPatSigType unicode qual ltype
+    full = hdr <+> equals <+> ppPatSigType unicode qual (noLoc sig_type)
     occ  = nameOccName . getName $ name
     fixs
       | summary   = noHtml
@@ -276,13 +286,13 @@ ppTyName = ppName Prefix
 
 
 ppSimpleSig :: LinksInfo -> Splice -> Unicode -> Qualification -> HideEmptyContexts -> SrcSpan
-            -> [DocName] -> HsType DocNameI
+            -> [DocName] -> HsSigType DocNameI
             -> Html
 ppSimpleSig links splice unicode qual emptyCtxts loc names typ =
     topDeclElem' names $ ppTypeSig True occNames ppTyp unicode
   where
     topDeclElem' = topDeclElem links loc splice
-    ppTyp = ppType unicode qual emptyCtxts typ
+    ppTyp = ppSigType unicode qual emptyCtxts typ
     occNames = map getOccName names
 
 
@@ -322,9 +332,9 @@ ppFamDecl summary associated links instances fixities loc doc decl splice unicod
 
     -- Individual equation of a closed type family
     ppFamDeclEqn :: TyFamInstEqn DocNameI -> SubDecl
-    ppFamDeclEqn (HsIB { hsib_body = FamEqn { feqn_tycon = L _ n
-                                            , feqn_rhs = rhs
-                                            , feqn_pats = ts } })
+    ppFamDeclEqn (FamEqn { feqn_tycon = L _ n
+                         , feqn_rhs = rhs
+                         , feqn_pats = ts })
       = ( ppAppNameTypeArgs n ts unicode qual
           <+> equals <+> ppType unicode qual HideEmptyContexts (unLoc rhs)
         , Nothing
@@ -518,7 +528,7 @@ ppShortClassDecl summary links (ClassDecl { tcdCtxt = lctxt, tcdLName = lname, t
 
                 -- ToDo: add associated type defaults
 
-            [ ppFunSig summary links loc doc names (hsSigTypeI typ)
+            [ ppFunSig summary links loc doc names typ
                        [] splice unicode pkg qual
               | L _ (ClassOpSig _ False lnames typ) <- sigs
               , let doc = lookupAnySubdoc (head names) subdocs
@@ -568,7 +578,7 @@ ppClassDecl summary links instances fixities loc d subdocs
                             doc = lookupAnySubdoc (unL $ fdLName $ unL at) subdocs
                             subfixs = [ f | f@(n',_) <- fixities, n == n' ] ]
 
-    methodBit = subMethods [ ppFunSig summary links loc doc [name] (hsSigTypeI typ)
+    methodBit = subMethods [ ppFunSig summary links loc doc [name] typ
                                       subfixs splice unicode pkg qual
                            | L _ (ClassOpSig _ _ lnames typ) <- lsigs
                            , name <- map unLoc lnames
@@ -692,7 +702,7 @@ ppInstanceSigs :: LinksInfo -> Splice -> Unicode -> Qualification
 ppInstanceSigs links splice unicode qual sigs = do
     TypeSig _ lnames typ <- sigs
     let names = map unLoc lnames
-        L _ rtyp = hsSigWcType typ
+        L _ rtyp = dropWildCards typ
     -- Instance methods signatures are synified and thus don't have a useful
     -- SrcSpan value. Use the methods name location instead.
     return $ ppSimpleSig links splice unicode qual HideEmptyContexts (getLoc $ head $ lnames) names rtyp
@@ -755,7 +765,7 @@ ppShortDataDecl summary dataInst dataDecl pats unicode qual
     pats1 = [ hsep [ keyword "pattern"
                    , hsep $ punctuate comma $ map (ppBinder summary . getOccName) lnames
                    , dcolon unicode
-                   , ppPatSigType unicode qual (hsSigTypeI typ)
+                   , ppPatSigType unicode qual typ
                    ]
             | (SigD _ (PatSynSig _ lnames typ),_) <- pats
             ]
@@ -863,7 +873,7 @@ ppShortConstrParts summary dataInst con unicode qual
 
       -- GADT constructor, e.g. 'Foo :: Int -> Foo'
       ConDeclGADT {} ->
-          ( hsep [ ppOcc, dcolon unicode, ppLType unicode qual HideEmptyContexts (getGADTConType con) ]
+          ( hsep [ ppOcc, dcolon unicode, ppLSigType unicode qual HideEmptyContexts (getGADTConType con) ]
           , noHtml
           , noHtml
           )
@@ -933,7 +943,7 @@ ppSideBySideConstr subdocs fixities unicode pkg qual (L _ con)
           | otherwise -> hsep [ ppOcc
                               , dcolon unicode
                               -- ++AZ++ make this prepend "{..}" when it is a record style GADT
-                              , ppLType unicode qual HideEmptyContexts (getGADTConType con)
+                              , ppLSigType unicode qual HideEmptyContexts (getGADTConType con)
                               , fixity
                               ]
 
@@ -1037,18 +1047,17 @@ ppSideBySidePat fixities unicode qual lnames typ (doc, argDocs) =
          | otherwise = hsep [ keyword "pattern"
                             , ppOcc
                             , dcolon unicode
-                            , ppPatSigType unicode qual (hsSigTypeI typ)
+                            , ppPatSigType unicode qual typ
                             , fixity
                             ]
 
     fieldPart
       | not hasArgDocs = []
-      | otherwise = [ subFields Nothing qual (ppSubSigLike unicode qual (unLoc patTy)
+      | otherwise = [ subFields Nothing qual (ppSubSigLike unicode qual (unLoc typ)
                                                         argDocs [] (dcolon unicode)
                                                         emptyCtxt) ]
 
-    patTy = hsSigTypeI typ
-    emptyCtxt = patSigContext patTy
+    emptyCtxt = patSigContext typ
 
 
 -- | Print the LHS of a data\/newtype declaration.
@@ -1102,6 +1111,9 @@ ppLType       unicode qual emptyCtxts y = ppType unicode qual emptyCtxts (unLoc
 ppLParendType unicode qual emptyCtxts y = ppParendType unicode qual emptyCtxts (unLoc y)
 ppLFunLhType  unicode qual emptyCtxts y = ppFunLhType unicode qual emptyCtxts (unLoc y)
 
+ppLSigType ::  Unicode -> Qualification -> HideEmptyContexts -> LHsSigType DocNameI -> Html
+ppLSigType unicode qual emptyCtxts y = ppSigType unicode qual emptyCtxts (unLoc y)
+
 ppCtxType :: Unicode -> Qualification -> HsType DocNameI -> Html
 ppCtxType unicode qual ty = ppr_mono_ty (reparenTypePrec PREC_CTX ty) unicode qual HideEmptyContexts
 
@@ -1110,6 +1122,9 @@ ppType       unicode qual emptyCtxts ty = ppr_mono_ty (reparenTypePrec PREC_TOP
 ppParendType unicode qual emptyCtxts ty = ppr_mono_ty (reparenTypePrec PREC_CON ty) unicode qual emptyCtxts
 ppFunLhType  unicode qual emptyCtxts ty = ppr_mono_ty (reparenTypePrec PREC_FUN ty) unicode qual emptyCtxts
 
+ppSigType ::  Unicode -> Qualification -> HideEmptyContexts -> HsSigType DocNameI -> Html
+ppSigType unicode qual emptyCtxts sig_ty = ppr_sig_ty (reparenSigType sig_ty) unicode qual emptyCtxts
+
 ppLHsTypeArg :: Unicode -> Qualification -> HideEmptyContexts -> LHsTypeArg DocNameI -> Html
 ppLHsTypeArg unicode qual emptyCtxts (HsValArg ty) = ppLParendType unicode qual emptyCtxts ty
 ppLHsTypeArg unicode qual emptyCtxts (HsTypeArg _ ki) = atSign unicode <>
@@ -1144,10 +1159,12 @@ ppLKind unicode qual y = ppKind unicode qual (unLoc y)
 ppKind :: Unicode -> Qualification -> HsKind DocNameI -> Html
 ppKind unicode qual ki = ppr_mono_ty (reparenTypePrec PREC_TOP ki) unicode qual HideEmptyContexts
 
-patSigContext :: LHsType DocNameI -> HideEmptyContexts
-patSigContext typ | hasNonEmptyContext typ && isFirstContextEmpty typ =  ShowEmptyToplevelContexts
-                  | otherwise = HideEmptyContexts
+patSigContext :: LHsSigType DocNameI -> HideEmptyContexts
+patSigContext sig_typ | hasNonEmptyContext typ && isFirstContextEmpty typ =  ShowEmptyToplevelContexts
+                      | otherwise = HideEmptyContexts
   where
+    typ = sig_body (unLoc sig_typ)
+
     hasNonEmptyContext t =
       case unLoc t of
         HsForAllTy _ _ s -> hasNonEmptyContext s
@@ -1164,9 +1181,16 @@ patSigContext typ | hasNonEmptyContext typ && isFirstContextEmpty typ =  ShowEmp
 
 -- | Pretty-print a pattern signature (all this does over 'ppLType' is slot in
 -- the right 'HideEmptyContext' value)
-ppPatSigType :: Unicode -> Qualification -> LHsType DocNameI -> Html
+ppPatSigType :: Unicode -> Qualification -> LHsSigType DocNameI -> Html
 ppPatSigType unicode qual typ =
-  let emptyCtxts = patSigContext typ in ppLType unicode qual emptyCtxts typ
+  let emptyCtxts = patSigContext typ in ppLSigType unicode qual emptyCtxts typ
+
+ppHsOuterTyVarBndrs :: RenderableBndrFlag flag
+                    => Unicode -> Qualification -> HsOuterTyVarBndrs flag DocNameI -> Html
+ppHsOuterTyVarBndrs unicode qual outer_bndrs = case outer_bndrs of
+  HsOuterImplicit{} -> noHtml
+  HsOuterExplicit{hso_bndrs = bndrs} ->
+    hsep (forallSymbol unicode : ppTyVars unicode qual bndrs) +++ dot
 
 ppForAllPart :: Unicode -> Qualification -> HsForAllTelescope DocNameI -> Html
 ppForAllPart unicode qual tele = case tele of
@@ -1176,6 +1200,10 @@ ppForAllPart unicode qual tele = case tele of
   HsForAllInvis { hsf_invis_bndrs = bndrs } ->
     hsep (forallSymbol unicode : ppTyVars unicode qual bndrs) +++ dot
 
+ppr_sig_ty :: HsSigType DocNameI -> Unicode -> Qualification -> HideEmptyContexts -> Html
+ppr_sig_ty (HsSig { sig_bndrs = outer_bndrs, sig_body = ltype }) unicode qual emptyCtxts
+  = ppHsOuterTyVarBndrs unicode qual outer_bndrs <+> ppr_mono_lty ltype unicode qual emptyCtxts
+
 ppr_mono_lty :: LHsType DocNameI -> Unicode -> Qualification -> HideEmptyContexts -> Html
 ppr_mono_lty ty = ppr_mono_ty (unLoc ty)