-%
+]%
% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[HsTypes]{Abstract syntax: user-defined types}
\begin{code}
module HsTypes (
- HsType(..), MonoUsageAnn(..), HsTyVar(..),
- HsContext, HsClassAssertion, HsPred(..)
-
- , mkHsForAllTy, mkHsUsForAllTy
- , getTyVarName, replaceTyVarName
- , pprParendHsType
- , pprForAll, pprHsContext, pprHsClassAssertion, pprHsPred
- , cmpHsType, cmpHsTypes, cmpHsContext, cmpHsPred
+ HsType(..), LHsType,
+ HsTyVarBndr(..), LHsTyVarBndr,
+ HsExplicitForAll(..),
+ HsContext, LHsContext,
+ HsPred(..), LHsPred,
+
+ LBangType, BangType, HsBang(..),
+ getBangType, getBangStrictness,
+
+ mkExplicitHsForAllTy, mkImplicitHsForAllTy,
+ hsTyVarName, hsTyVarNames, replaceTyVarName,
+ hsLTyVarName, hsLTyVarNames, hsLTyVarLocName, hsLTyVarLocNames,
+ splitHsInstDeclTy,
+
+ -- Type place holder
+ PostTcType, placeHolderType,
+
+ -- Name place holder
+ SyntaxName, placeHolderName,
+
+ -- Printing
+ pprParendHsType, pprHsForAll, pprHsContext, ppr_hs_context, pprHsTyVarBndr
) where
#include "HsVersions.h"
-import Type ( Kind, UsageAnn(..) )
-import PprType ( {- instance Outputable Kind -} )
+import {-# SOURCE #-} HsExpr ( HsSplice, pprSplice )
+
+import Type ( Type )
+import Kind ( {- instance Outputable Kind -}, Kind,
+ pprParendKind, pprKind, isLiftedTypeKind )
+import Name ( Name, mkInternalName )
+import OccName ( mkVarOcc )
+import BasicTypes ( IPName, Boxity, tupleParens )
+import PrelNames ( unboundKey )
+import SrcLoc ( noSrcLoc, Located(..), unLoc, noSrcSpan )
+import CmdLineOpts ( opt_PprStyle_Debug )
import Outputable
-import Util ( thenCmp, cmpList )
\end{code}
-This is the syntax for types as seen in type signatures.
+
+%************************************************************************
+%* *
+\subsection{Annotating the syntax}
+%* *
+%************************************************************************
\begin{code}
-type HsContext name = [HsPred name]
-type HsClassAssertion name = (name, [HsType name])
--- The type is usually a type variable, but it
--- doesn't have to be when reading interface files
-data HsPred name =
- HsPClass name [HsType name]
- | HsPIParam name (HsType name)
+type PostTcType = Type -- Used for slots in the abstract syntax
+ -- where we want to keep slot for a type
+ -- to be added by the type checker...but
+ -- before typechecking it's just bogus
-data HsType name
- = HsForAllTy (Maybe [HsTyVar name]) -- Nothing for implicitly quantified signatures
- (HsContext name)
- (HsType name)
+placeHolderType :: PostTcType -- Used before typechecking
+placeHolderType = panic "Evaluated the place holder for a PostTcType"
- | MonoTyVar name -- Type variable
- | MonoTyApp (HsType name)
- (HsType name)
+type SyntaxName = Name -- These names are filled in by the renamer
+ -- Before then they are a placeHolderName (so that
+ -- we can still print the HsSyn)
+ -- They correspond to "rebindable syntax";
+ -- See RnEnv.lookupSyntaxName
- | MonoFunTy (HsType name) -- function type
- (HsType name)
+placeHolderName :: SyntaxName
+placeHolderName = mkInternalName unboundKey
+ (mkVarOcc FSLIT("syntaxPlaceHolder"))
+ noSrcLoc
+\end{code}
- | MonoListTy (HsType name) -- Element type
+%************************************************************************
+%* *
+\subsection{Bang annotations}
+%* *
+%************************************************************************
- | MonoTupleTy [HsType name] -- Element types (length gives arity)
- Bool -- boxed?
+\begin{code}
+type LBangType name = Located (BangType name)
+type BangType name = HsType name -- Bangs are in the HsType data type
+
+data HsBang = HsNoBang -- Only used as a return value for getBangStrictness,
+ -- never appears on a HsBangTy
+ | HsStrict -- !
+ | HsUnbox -- {-# UNPACK #-} ! (GHC extension, meaning "unbox")
+
+instance Outputable HsBang where
+ ppr (HsNoBang) = empty
+ ppr (HsStrict) = char '!'
+ ppr (HsUnbox) = ptext SLIT("!!")
+
+getBangType :: LHsType a -> LHsType a
+getBangType (L _ (HsBangTy _ ty)) = ty
+getBangType ty = ty
+
+getBangStrictness :: LHsType a -> HsBang
+getBangStrictness (L _ (HsBangTy s _)) = s
+getBangStrictness _ = HsNoBang
+\end{code}
- -- these next two are only used in interfaces
- | MonoDictTy name -- Class
- [HsType name]
- | MonoUsgTy (MonoUsageAnn name)
- (HsType name)
+%************************************************************************
+%* *
+\subsection{Data types}
+%* *
+%************************************************************************
- | MonoUsgForAllTy name
- (HsType name)
+This is the syntax for types as seen in type signatures.
-data MonoUsageAnn name
- = MonoUsOnce
- | MonoUsMany
- | MonoUsVar name
-
+\begin{code}
+type LHsContext name = Located (HsContext name)
--- Combine adjacent for-alls.
--- The following awkward situation can happen otherwise:
--- f :: forall a. ((Num a) => Int)
--- might generate HsForAll (Just [a]) [] (HsForAll Nothing [Num a] t)
--- Then a isn't discovered as ambiguous, and we abstract the AbsBinds wrt []
--- but the export list abstracts f wrt [a]. Disaster.
---
--- A valid type must have one for-all at the top of the type, or of the fn arg types
+type HsContext name = [LHsPred name]
-mkHsForAllTy (Just []) [] ty = ty -- Explicit for-all with no tyvars
-mkHsForAllTy mtvs1 [] (HsForAllTy mtvs2 ctxt ty) = mkHsForAllTy (mtvs1 `plus` mtvs2) ctxt ty
- where
- mtvs1 `plus` Nothing = mtvs1
- Nothing `plus` mtvs2 = mtvs2
- (Just tvs1) `plus` (Just tvs2) = Just (tvs1 ++ tvs2)
-mkHsForAllTy tvs ctxt ty = HsForAllTy tvs ctxt ty
+type LHsPred name = Located (HsPred name)
-mkHsUsForAllTy uvs ty = foldr (\ uv ty -> MonoUsgForAllTy uv ty)
- ty uvs
+data HsPred name = HsClassP name [LHsType name]
+ | HsIParam (IPName name) (LHsType name)
-data HsTyVar name
- = UserTyVar name
- | IfaceTyVar name Kind
- -- *** NOTA BENE *** A "monotype" in a pragma can have
- -- for-alls in it, (mostly to do with dictionaries). These
- -- must be explicitly Kinded.
+type LHsType name = Located (HsType name)
-getTyVarName (UserTyVar n) = n
-getTyVarName (IfaceTyVar n _) = n
+data HsType name
+ = HsForAllTy HsExplicitForAll -- Renamer leaves this flag unchanged, to record the way
+ -- the user wrote it originally, so that the printer can
+ -- print it as the user wrote it
+ [LHsTyVarBndr name] -- With ImplicitForAll, this is the empty list
+ -- until the renamer fills in the variables
+ (LHsContext name)
+ (LHsType name)
-replaceTyVarName :: HsTyVar name1 -> name2 -> HsTyVar name2
-replaceTyVarName (UserTyVar n) n' = UserTyVar n'
-replaceTyVarName (IfaceTyVar n k) n' = IfaceTyVar n' k
-\end{code}
+ | HsTyVar name -- Type variable or type constructor
+ | HsBangTy HsBang (LHsType name) -- Bang-style type annotations
-%************************************************************************
-%* *
-\subsection{Pretty printing}
-%* *
-%************************************************************************
+ | HsAppTy (LHsType name)
+ (LHsType name)
-\begin{code}
+ | HsFunTy (LHsType name) -- function type
+ (LHsType name)
-instance (Outputable name) => Outputable (HsType name) where
- ppr ty = pprHsType ty
+ | HsListTy (LHsType name) -- Element type
-instance (Outputable name) => Outputable (HsTyVar name) where
- ppr (UserTyVar name) = ppr name
- ppr (IfaceTyVar name kind) = hsep [ppr name, dcolon, ppr kind]
+ | HsPArrTy (LHsType name) -- Elem. type of parallel array: [:t:]
--- Better to see those for-alls
--- pprForAll [] = empty
-pprForAll tvs = ptext SLIT("forall") <+> interppSP tvs <> ptext SLIT(".")
+ | HsTupleTy Boxity
+ [LHsType name] -- Element types (length gives arity)
-pprHsContext :: (Outputable name) => HsContext name -> SDoc
-pprHsContext [] = empty
-pprHsContext context = parens (hsep (punctuate comma (map pprHsPred context))) <+> ptext SLIT("=>")
+ | HsOpTy (LHsType name) (Located name) (LHsType name)
-pprHsClassAssertion :: (Outputable name) => HsClassAssertion name -> SDoc
-pprHsClassAssertion (clas, tys)
- = ppr clas <+> hsep (map pprParendHsType tys)
+ | HsParTy (LHsType name)
+ -- Parenthesis preserved for the precedence re-arrangement in RnTypes
+ -- It's important that a * (b + c) doesn't get rearranged to (a*b) + c!
+ --
+ -- However, NB that toHsType doesn't add HsParTys (in an effort to keep
+ -- interface files smaller), so when printing a HsType we may need to
+ -- add parens.
-pprHsPred :: (Outputable name) => HsPred name -> SDoc
-pprHsPred (HsPClass clas tys)
- = ppr clas <+> hsep (map pprParendHsType tys)
-pprHsPred (HsPIParam n ty)
- = hsep [char '?' <> ppr n, text "::", ppr ty]
-\end{code}
+ | HsNumTy Integer -- Generics only
-\begin{code}
-pREC_TOP = (0 :: Int)
-pREC_FUN = (1 :: Int)
-pREC_CON = (2 :: Int)
+ | HsPredTy (HsPred name) -- Only used in the type of an instance
+ -- declaration, eg. Eq [a] -> Eq a
+ -- ^^^^
+ -- HsPredTy
+ -- Note no need for location info on the
+ -- enclosed HsPred; the one on the type will do
-maybeParen :: Bool -> SDoc -> SDoc
-maybeParen True p = parens p
-maybeParen False p = p
-
--- printing works more-or-less as for Types
+ | HsKindSig (LHsType name) -- (ty :: kind)
+ Kind -- A type with a kind signature
-pprHsType, pprParendHsType :: (Outputable name) => HsType name -> SDoc
+ | HsSpliceTy (HsSplice name)
-pprHsType ty = ppr_mono_ty pREC_TOP ty
-pprParendHsType ty = ppr_mono_ty pREC_CON ty
+data HsExplicitForAll = Explicit | Implicit
-ppr_mono_ty ctxt_prec (HsForAllTy maybe_tvs ctxt ty)
- = maybeParen (ctxt_prec >= pREC_FUN) $
- sep [pp_tvs, pprHsContext ctxt, pprHsType ty]
- where
- pp_tvs = case maybe_tvs of
- Just tvs -> pprForAll tvs
- Nothing -> text "{- implicit forall -}"
+-----------------------
+-- Combine adjacent for-alls.
+-- The following awkward situation can happen otherwise:
+-- f :: forall a. ((Num a) => Int)
+-- might generate HsForAll (Just [a]) [] (HsForAll Nothing [Num a] t)
+-- Then a isn't discovered as ambiguous, and we abstract the AbsBinds wrt []
+-- but the export list abstracts f wrt [a]. Disaster.
+--
+-- A valid type must have one for-all at the top of the type, or of the fn arg types
-ppr_mono_ty ctxt_prec (MonoTyVar name)
- = ppr name
+mkImplicitHsForAllTy ctxt ty = mkHsForAllTy Implicit [] ctxt ty
+mkExplicitHsForAllTy tvs ctxt ty = mkHsForAllTy Explicit tvs ctxt ty
-ppr_mono_ty ctxt_prec (MonoFunTy ty1 ty2)
- = let p1 = ppr_mono_ty pREC_FUN ty1
- p2 = ppr_mono_ty pREC_TOP ty2
- in
- maybeParen (ctxt_prec >= pREC_FUN)
- (sep [p1, (<>) (ptext SLIT("-> ")) p2])
+mkHsForAllTy :: HsExplicitForAll -> [LHsTyVarBndr name] -> LHsContext name -> LHsType name -> HsType name
+-- Smart constructor for HsForAllTy
+mkHsForAllTy exp tvs (L _ []) ty = mk_forall_ty exp tvs ty
+mkHsForAllTy exp tvs ctxt ty = HsForAllTy exp tvs ctxt ty
-ppr_mono_ty ctxt_prec (MonoTupleTy tys True)
- = parens (sep (punctuate comma (map ppr tys)))
-ppr_mono_ty ctxt_prec (MonoTupleTy tys False)
- = ptext SLIT("(#") <> sep (punctuate comma (map ppr tys)) <> ptext SLIT("#)")
+-- mk_forall_ty makes a pure for-all type (no context)
+mk_forall_ty Explicit [] ty = unLoc ty -- Explicit for-all with no tyvars
+mk_forall_ty exp tvs (L _ (HsParTy ty)) = mk_forall_ty exp tvs ty
+mk_forall_ty exp1 tvs1 (L _ (HsForAllTy exp2 tvs2 ctxt ty)) = mkHsForAllTy (exp1 `plus` exp2) (tvs1 ++ tvs2) ctxt ty
+mk_forall_ty exp tvs ty = HsForAllTy exp tvs (L noSrcSpan []) ty
-ppr_mono_ty ctxt_prec (MonoListTy ty)
- = brackets (ppr_mono_ty pREC_TOP ty)
+Implicit `plus` Implicit = Implicit
+exp1 `plus` exp2 = Explicit
-ppr_mono_ty ctxt_prec (MonoTyApp fun_ty arg_ty)
- = maybeParen (ctxt_prec >= pREC_CON)
- (hsep [ppr_mono_ty pREC_FUN fun_ty, ppr_mono_ty pREC_CON arg_ty])
+type LHsTyVarBndr name = Located (HsTyVarBndr name)
-ppr_mono_ty ctxt_prec (MonoDictTy clas tys)
- = ppr clas <+> hsep (map (ppr_mono_ty pREC_CON) tys)
+data HsTyVarBndr name
+ = UserTyVar name
+ | KindedTyVar name Kind
+ -- *** NOTA BENE *** A "monotype" in a pragma can have
+ -- for-alls in it, (mostly to do with dictionaries). These
+ -- must be explicitly Kinded.
-ppr_mono_ty ctxt_prec ty@(MonoUsgForAllTy _ _)
- = maybeParen (ctxt_prec >= pREC_FUN) $
- sep [ ptext SLIT("__fuall") <+> brackets pp_uvars <+> ptext SLIT("=>"),
- ppr_mono_ty pREC_TOP sigma
- ]
- where
- (uvars,sigma) = split [] ty
- pp_uvars = interppSP uvars
+hsTyVarName :: HsTyVarBndr name -> name
+hsTyVarName (UserTyVar n) = n
+hsTyVarName (KindedTyVar n _) = n
+
+hsLTyVarName :: LHsTyVarBndr name -> name
+hsLTyVarName = hsTyVarName . unLoc
- split uvs (MonoUsgForAllTy uv ty') = split (uv:uvs) ty'
- split uvs ty' = (reverse uvs,ty')
+hsTyVarNames :: [HsTyVarBndr name] -> [name]
+hsTyVarNames tvs = map hsTyVarName tvs
-ppr_mono_ty ctxt_prec (MonoUsgTy u ty)
- = maybeParen (ctxt_prec >= pREC_CON) $
- ptext SLIT("__u") <+> pp_ua <+> ppr_mono_ty pREC_CON ty
+hsLTyVarNames :: [LHsTyVarBndr name] -> [name]
+hsLTyVarNames = map hsLTyVarName
+
+hsLTyVarLocName :: LHsTyVarBndr name -> Located name
+hsLTyVarLocName = fmap hsTyVarName
+
+hsLTyVarLocNames :: [LHsTyVarBndr name] -> [Located name]
+hsLTyVarLocNames = map hsLTyVarLocName
+
+replaceTyVarName :: HsTyVarBndr name1 -> name2 -> HsTyVarBndr name2
+replaceTyVarName (UserTyVar n) n' = UserTyVar n'
+replaceTyVarName (KindedTyVar n k) n' = KindedTyVar n' k
+\end{code}
+
+
+\begin{code}
+splitHsInstDeclTy
+ :: OutputableBndr name
+ => HsType name
+ -> ([LHsTyVarBndr name], HsContext name, name, [LHsType name])
+ -- Split up an instance decl type, returning the pieces
+
+splitHsInstDeclTy inst_ty
+ = case inst_ty of
+ HsParTy (L _ ty) -> splitHsInstDeclTy ty
+ HsForAllTy _ tvs cxt (L _ ty) -> split_tau tvs (unLoc cxt) ty
+ other -> split_tau [] [] other
+ -- The type vars should have been computed by now, even if they were implicit
where
- pp_ua = case u of
- MonoUsOnce -> ptext SLIT("-")
- MonoUsMany -> ptext SLIT("!")
- MonoUsVar uv -> ppr uv
+ split_tau tvs cxt (HsPredTy (HsClassP cls tys)) = (tvs, cxt, cls, tys)
+ split_tau tvs cxt (HsParTy (L _ ty)) = split_tau tvs cxt ty
\end{code}
%************************************************************************
%* *
-\subsection{Comparison}
+\subsection{Pretty printing}
%* *
%************************************************************************
-We do define a specialised equality for these \tr{*Type} types; used
-in checking interfaces. Most any other use is likely to be {\em
-wrong}, so be careful!
+NB: these types get printed into interface files, so
+ don't change the printing format lightly
\begin{code}
-cmpHsTyVar :: (a -> a -> Ordering) -> HsTyVar a -> HsTyVar a -> Ordering
-cmpHsType :: (a -> a -> Ordering) -> HsType a -> HsType a -> Ordering
-cmpHsTypes :: (a -> a -> Ordering) -> [HsType a] -> [HsType a] -> Ordering
-cmpHsContext :: (a -> a -> Ordering) -> HsContext a -> HsContext a -> Ordering
-cmpHsPred :: (a -> a -> Ordering) -> HsPred a -> HsPred a -> Ordering
-
-cmpHsTyVar cmp (UserTyVar v1) (UserTyVar v2) = v1 `cmp` v2
-cmpHsTyVar cmp (IfaceTyVar v1 _) (IfaceTyVar v2 _) = v1 `cmp` v2
-cmpHsTyVar cmp (UserTyVar _) other = LT
-cmpHsTyVar cmp other1 other2 = GT
+instance (OutputableBndr name) => Outputable (HsType name) where
+ ppr ty = pprHsType ty
-cmpHsTypes cmp [] [] = EQ
-cmpHsTypes cmp [] tys2 = LT
-cmpHsTypes cmp tys1 [] = GT
-cmpHsTypes cmp (ty1:tys1) (ty2:tys2) = cmpHsType cmp ty1 ty2 `thenCmp` cmpHsTypes cmp tys1 tys2
+instance (Outputable name) => Outputable (HsTyVarBndr name) where
+ ppr (UserTyVar name) = ppr name
+ ppr (KindedTyVar name kind) = pprHsTyVarBndr name kind
-cmpHsType cmp (HsForAllTy tvs1 c1 t1) (HsForAllTy tvs2 c2 t2)
- = cmpMaybe (cmpList (cmpHsTyVar cmp)) tvs1 tvs2 `thenCmp`
- cmpHsContext cmp c1 c2 `thenCmp`
- cmpHsType cmp t1 t2
+instance OutputableBndr name => Outputable (HsPred name) where
+ ppr (HsClassP clas tys) = ppr clas <+> hsep (map (pprParendHsType.unLoc) tys)
+ ppr (HsIParam n ty) = hsep [ppr n, dcolon, ppr ty]
-cmpHsType cmp (MonoTyVar n1) (MonoTyVar n2)
- = cmp n1 n2
+pprHsTyVarBndr :: Outputable name => name -> Kind -> SDoc
+pprHsTyVarBndr name kind | isLiftedTypeKind kind = ppr name
+ | otherwise = hsep [ppr name, dcolon, pprParendKind kind]
-cmpHsType cmp (MonoTupleTy tys1 b1) (MonoTupleTy tys2 b2)
- = (b1 `compare` b2) `thenCmp` cmpHsTypes cmp tys1 tys2
+pprHsForAll exp tvs cxt
+ | show_forall = forall_part <+> pprHsContext (unLoc cxt)
+ | otherwise = pprHsContext (unLoc cxt)
+ where
+ show_forall = opt_PprStyle_Debug
+ || (not (null tvs) && is_explicit)
+ is_explicit = case exp of {Explicit -> True; Implicit -> False}
+ forall_part = ptext SLIT("forall") <+> interppSP tvs <> dot
-cmpHsType cmp (MonoListTy ty1) (MonoListTy ty2)
- = cmpHsType cmp ty1 ty2
+pprHsContext :: (OutputableBndr name) => HsContext name -> SDoc
+pprHsContext [] = empty
+pprHsContext cxt = ppr_hs_context cxt <+> ptext SLIT("=>")
-cmpHsType cmp (MonoTyApp fun_ty1 arg_ty1) (MonoTyApp fun_ty2 arg_ty2)
- = cmpHsType cmp fun_ty1 fun_ty2 `thenCmp` cmpHsType cmp arg_ty1 arg_ty2
+ppr_hs_context [] = empty
+ppr_hs_context cxt = parens (interpp'SP cxt)
+\end{code}
-cmpHsType cmp (MonoFunTy a1 b1) (MonoFunTy a2 b2)
- = cmpHsType cmp a1 a2 `thenCmp` cmpHsType cmp b1 b2
+\begin{code}
+pREC_TOP = (0 :: Int) -- type in ParseIface.y
+pREC_FUN = (1 :: Int) -- btype in ParseIface.y
+ -- Used for LH arg of (->)
+pREC_OP = (2 :: Int) -- Used for arg of any infix operator
+ -- (we don't keep their fixities around)
+pREC_CON = (3 :: Int) -- Used for arg of type applicn:
+ -- always parenthesise unless atomic
+
+maybeParen :: Int -- Precedence of context
+ -> Int -- Precedence of top-level operator
+ -> SDoc -> SDoc -- Wrap in parens if (ctxt >= op)
+maybeParen ctxt_prec op_prec p | ctxt_prec >= op_prec = parens p
+ | otherwise = p
+
+-- printing works more-or-less as for Types
-cmpHsType cmp (MonoDictTy c1 tys1) (MonoDictTy c2 tys2)
- = cmp c1 c2 `thenCmp` cmpHsTypes cmp tys1 tys2
+pprHsType, pprParendHsType :: (OutputableBndr name) => HsType name -> SDoc
-cmpHsType cmp (MonoUsgTy u1 ty1) (MonoUsgTy u2 ty2)
- = cmpUsg cmp u1 u2 `thenCmp` cmpHsType cmp ty1 ty2
+pprHsType ty = getPprStyle $ \sty -> ppr_mono_ty pREC_TOP (prepare sty ty)
+pprParendHsType ty = ppr_mono_ty pREC_CON ty
-cmpHsType cmp ty1 ty2 -- tags must be different
- = let tag1 = tag ty1
- tag2 = tag ty2
+-- Before printing a type
+-- (a) Remove outermost HsParTy parens
+-- (b) Drop top-level for-all type variables in user style
+-- since they are implicit in Haskell
+prepare sty (HsParTy ty) = prepare sty (unLoc ty)
+prepare sty ty = ty
+
+ppr_mono_lty ctxt_prec ty = ppr_mono_ty ctxt_prec (unLoc ty)
+
+ppr_mono_ty ctxt_prec (HsForAllTy exp tvs ctxt ty)
+ = maybeParen ctxt_prec pREC_FUN $
+ sep [pprHsForAll exp tvs ctxt, ppr_mono_lty pREC_TOP ty]
+
+-- gaw 2004
+ppr_mono_ty ctxt_prec (HsBangTy b ty) = ppr b <> ppr ty
+ppr_mono_ty ctxt_prec (HsTyVar name) = ppr name
+ppr_mono_ty ctxt_prec (HsFunTy ty1 ty2) = ppr_fun_ty ctxt_prec ty1 ty2
+ppr_mono_ty ctxt_prec (HsTupleTy con tys) = tupleParens con (interpp'SP tys)
+ppr_mono_ty ctxt_prec (HsKindSig ty kind) = parens (ppr_mono_lty pREC_TOP ty <+> dcolon <+> pprKind kind)
+ppr_mono_ty ctxt_prec (HsListTy ty) = brackets (ppr_mono_lty pREC_TOP ty)
+ppr_mono_ty ctxt_prec (HsPArrTy ty) = pabrackets (ppr_mono_lty pREC_TOP ty)
+ppr_mono_ty ctxt_prec (HsPredTy pred) = braces (ppr pred)
+ppr_mono_ty ctxt_prec (HsNumTy n) = integer n -- generics only
+ppr_mono_ty ctxt_prec (HsSpliceTy s) = pprSplice s
+
+ppr_mono_ty ctxt_prec (HsAppTy fun_ty arg_ty)
+ = maybeParen ctxt_prec pREC_CON $
+ hsep [ppr_mono_lty pREC_FUN fun_ty, ppr_mono_lty pREC_CON arg_ty]
+
+ppr_mono_ty ctxt_prec (HsOpTy ty1 op ty2)
+ = maybeParen ctxt_prec pREC_OP $
+ ppr_mono_lty pREC_OP ty1 <+> ppr op <+> ppr_mono_lty pREC_OP ty2
+
+ppr_mono_ty ctxt_prec (HsParTy ty)
+ = parens (ppr_mono_lty pREC_TOP ty)
+ -- Put the parens in where the user did
+ -- But we still use the precedence stuff to add parens because
+ -- toHsType doesn't put in any HsParTys, so we may still need them
+
+--------------------------
+ppr_fun_ty ctxt_prec ty1 ty2
+ = let p1 = ppr_mono_lty pREC_FUN ty1
+ p2 = ppr_mono_lty pREC_TOP ty2
in
- if tag1 _LT_ tag2 then LT else GT
- where
- tag (MonoTyVar n1) = (ILIT(1) :: FAST_INT)
- tag (MonoTupleTy tys1 _) = ILIT(2)
- tag (MonoListTy ty1) = ILIT(3)
- tag (MonoTyApp tc1 tys1) = ILIT(4)
- tag (MonoFunTy a1 b1) = ILIT(5)
- tag (MonoDictTy c1 tys1) = ILIT(6)
- tag (MonoUsgTy c1 ty1) = ILIT(7)
- tag (MonoUsgForAllTy uv1 ty1) = ILIT(8)
- tag (HsForAllTy _ _ _) = ILIT(9)
-
--------------------
-cmpHsContext cmp a b
- = cmpList (cmpHsPred cmp) a b
-
-cmpHsPred cmp (HsPClass c1 tys1) (HsPClass c2 tys2)
- = cmp c1 c2 `thenCmp` cmpHsTypes cmp tys1 tys2
-cmpHsPred cmp (HsPIParam n1 ty1) (HsPIParam n2 ty2)
- = cmp n1 n2 `thenCmp` cmpHsType cmp ty1 ty2
-cmpHsPred cmp (HsPClass _ _) (HsPIParam _ _) = LT
-cmpHsPred cmp _ _ = GT
-
-cmpUsg cmp MonoUsOnce MonoUsOnce = EQ
-cmpUsg cmp MonoUsMany MonoUsMany = EQ
-cmpUsg cmp (MonoUsVar u1) (MonoUsVar u2) = cmp u1 u2
-
-cmpUsg cmp ua1 ua2 -- tags must be different
- = let tag1 = tag ua1
- tag2 = tag ua2
- in
- if tag1 _LT_ tag2 then LT else GT
- where
- tag MonoUsOnce = (ILIT(1) :: FAST_INT)
- tag MonoUsMany = ILIT(2)
- tag (MonoUsVar _) = ILIT(3)
-
--- Should be in Maybes, I guess
-cmpMaybe cmp Nothing Nothing = EQ
-cmpMaybe cmp Nothing (Just x) = LT
-cmpMaybe cmp (Just x) Nothing = GT
-cmpMaybe cmp (Just x) (Just y) = x `cmp` y
+ maybeParen ctxt_prec pREC_FUN $
+ sep [p1, ptext SLIT("->") <+> p2]
+
+--------------------------
+pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]")
\end{code}
+
+