X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FhsSyn%2FHsTypes.lhs;h=a5e89828265f0913f91f9f3369b204198c82b0da;hp=ac6a0f9751162ddb0cf40e656ce1df4aa051c9b5;hb=1a9245caefb80a3c4c5965aaacdf9a607e792e1c;hpb=8c839b096be9a3fd44f4f681ed7f14fd95fe8ff9 diff --git a/compiler/hsSyn/HsTypes.lhs b/compiler/hsSyn/HsTypes.lhs index ac6a0f9..a5e8982 100644 --- a/compiler/hsSyn/HsTypes.lhs +++ b/compiler/hsSyn/HsTypes.lhs @@ -1,42 +1,51 @@ % +% (c) The University of Glasgow 2006 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % -\section[HsTypes]{Abstract syntax: user-defined types} + +HsTypes: Abstract syntax: user-defined types \begin{code} +{-# LANGUAGE DeriveDataTypeable #-} + module HsTypes ( HsType(..), LHsType, HsTyVarBndr(..), LHsTyVarBndr, - HsExplicitForAll(..), + HsExplicitFlag(..), HsContext, LHsContext, HsPred(..), LHsPred, + HsQuasiQuote(..), LBangType, BangType, HsBang(..), getBangType, getBangStrictness, + + ConDeclField(..), pprConDeclFields, - mkExplicitHsForAllTy, mkImplicitHsForAllTy, + mkExplicitHsForAllTy, mkImplicitHsForAllTy, hsExplicitTvs, hsTyVarName, hsTyVarNames, replaceTyVarName, + hsTyVarKind, hsTyVarNameKind, hsLTyVarName, hsLTyVarNames, hsLTyVarLocName, hsLTyVarLocNames, splitHsInstDeclTy, splitHsFunType, -- Type place holder - PostTcType, placeHolderType, + PostTcType, placeHolderType, PostTcKind, placeHolderKind, -- Printing - pprParendHsType, pprHsForAll, pprHsContext, ppr_hs_context, pprHsTyVarBndr + pprParendHsType, pprHsForAll, pprHsContext, ppr_hs_context, ) where -#include "HsVersions.h" - import {-# SOURCE #-} HsExpr ( HsSplice, pprSplice ) -import Type ( Type ) -import Kind ( {- instance Outputable Kind -} Kind, - pprParendKind, pprKind, isLiftedTypeKind ) -import BasicTypes ( IPName, Boxity, tupleParens ) -import SrcLoc ( Located(..), unLoc, noSrcSpan ) -import StaticFlags ( opt_PprStyle_Debug ) +import NameSet( FreeVars ) +import Type +import HsDoc +import BasicTypes +import SrcLoc +import StaticFlags import Outputable +import FastString + +import Data.Data \end{code} @@ -47,6 +56,7 @@ import Outputable %************************************************************************ \begin{code} +type PostTcKind = Kind 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 @@ -54,8 +64,34 @@ type PostTcType = Type -- Used for slots in the abstract syntax placeHolderType :: PostTcType -- Used before typechecking placeHolderType = panic "Evaluated the place holder for a PostTcType" + +placeHolderKind :: PostTcKind -- Used before typechecking +placeHolderKind = panic "Evaluated the place holder for a PostTcKind" +\end{code} + +%************************************************************************ +%* * + Quasi quotes; used in types and elsewhere +%* * +%************************************************************************ + +\begin{code} +data HsQuasiQuote id = HsQuasiQuote + id -- The quasi-quoter + SrcSpan -- The span of the enclosed string + FastString -- The enclosed string + deriving (Data, Typeable) + +instance OutputableBndr id => Outputable (HsQuasiQuote id) where + ppr = ppr_qq + +ppr_qq :: OutputableBndr id => HsQuasiQuote id -> SDoc +ppr_qq (HsQuasiQuote quoter _ quote) = + char '[' <> ppr quoter <> ptext (sLit "|") <> + ppr quote <> ptext (sLit "|]") \end{code} + %************************************************************************ %* * \subsection{Bang annotations} @@ -66,16 +102,6 @@ placeHolderType = panic "Evaluated the place holder for a PostTcType" 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 @@ -101,13 +127,15 @@ type HsContext name = [LHsPred name] type LHsPred name = Located (HsPred name) -data HsPred name = HsClassP name [LHsType name] +data HsPred name = HsClassP name [LHsType name] -- class constraint + | HsEqualP (LHsType name) (LHsType name)-- equality constraint | HsIParam (IPName name) (LHsType name) + deriving (Data, Typeable) type LHsType name = Located (HsType name) data HsType name - = HsForAllTy HsExplicitForAll -- Renamer leaves this flag unchanged, to record the way + = HsForAllTy HsExplicitFlag -- 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 @@ -117,8 +145,6 @@ data HsType name | HsTyVar name -- Type variable or type constructor - | HsBangTy HsBang (LHsType name) -- Bang-style type annotations - | HsAppTy (LHsType name) (LHsType name) @@ -149,14 +175,34 @@ data HsType name -- ^^^^ -- HsPredTy -- Note no need for location info on the - -- enclosed HsPred; the one on the type will do + -- Enclosed HsPred; the one on the type will do | HsKindSig (LHsType name) -- (ty :: kind) Kind -- A type with a kind signature - | HsSpliceTy (HsSplice name) + | HsQuasiQuoteTy (HsQuasiQuote name) + + | HsSpliceTy (HsSplice name) + FreeVars -- Variables free in the splice (filled in by renamer) + PostTcKind + + | HsDocTy (LHsType name) LHsDocString -- A documented type + + | HsBangTy HsBang (LHsType name) -- Bang-style type annotations + | HsRecTy [ConDeclField name] -- Only in data type declarations -data HsExplicitForAll = Explicit | Implicit + | HsCoreTy Type -- An escape hatch for tunnelling a *closed* + -- Core Type through HsSyn. + + deriving (Data, Typeable) + +data HsExplicitFlag = Explicit | Implicit deriving (Data, Typeable) + +data ConDeclField name -- Record fields have Haddoc docs on them + = ConDeclField { cd_fld_name :: Located name, + cd_fld_type :: LBangType name, + cd_fld_doc :: Maybe LHsDocString } + deriving (Data, Typeable) ----------------------- -- Combine adjacent for-alls. @@ -168,15 +214,18 @@ data HsExplicitForAll = Explicit | Implicit -- -- A valid type must have one for-all at the top of the type, or of the fn arg types +mkImplicitHsForAllTy :: LHsContext name -> LHsType name -> HsType name +mkExplicitHsForAllTy :: [LHsTyVarBndr name] -> LHsContext name -> LHsType name -> HsType name mkImplicitHsForAllTy ctxt ty = mkHsForAllTy Implicit [] ctxt ty mkExplicitHsForAllTy tvs ctxt ty = mkHsForAllTy Explicit tvs ctxt ty -mkHsForAllTy :: HsExplicitForAll -> [LHsTyVarBndr name] -> LHsContext name -> LHsType name -> HsType name +mkHsForAllTy :: HsExplicitFlag -> [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 -- mk_forall_ty makes a pure for-all type (no context) +mk_forall_ty :: HsExplicitFlag -> [LHsTyVarBndr name] -> LHsType name -> HsType name 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 @@ -186,22 +235,43 @@ mk_forall_ty exp tvs ty = HsForAllTy exp tvs (L noSrcSpan []) ty -- (see the sigtype production in Parser.y.pp) -- so that (forall. ty) isn't implicitly quantified +plus :: HsExplicitFlag -> HsExplicitFlag -> HsExplicitFlag Implicit `plus` Implicit = Implicit -exp1 `plus` exp2 = Explicit +_ `plus` _ = Explicit +hsExplicitTvs :: LHsType name -> [name] +-- The explicitly-given forall'd type variables of a HsType +hsExplicitTvs (L _ (HsForAllTy Explicit tvs _ _)) = hsLTyVarNames tvs +hsExplicitTvs _ = [] + +--------------------- type LHsTyVarBndr name = Located (HsTyVarBndr name) 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. + = UserTyVar -- No explicit kinding + name -- See Note [Printing KindedTyVars] + PostTcKind + + | 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. + deriving (Data, Typeable) hsTyVarName :: HsTyVarBndr name -> name -hsTyVarName (UserTyVar n) = n +hsTyVarName (UserTyVar n _) = n hsTyVarName (KindedTyVar n _) = n +hsTyVarKind :: HsTyVarBndr name -> Kind +hsTyVarKind (UserTyVar _ k) = k +hsTyVarKind (KindedTyVar _ k) = k + +hsTyVarNameKind :: HsTyVarBndr name -> (name, Kind) +hsTyVarNameKind (UserTyVar n k) = (n,k) +hsTyVarNameKind (KindedTyVar n k) = (n,k) + hsLTyVarName :: LHsTyVarBndr name -> name hsLTyVarName = hsTyVarName . unLoc @@ -218,8 +288,8 @@ 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 +replaceTyVarName (UserTyVar _ k) n' = UserTyVar n' k +replaceTyVarName (KindedTyVar _ k) n' = KindedTyVar n' k \end{code} @@ -239,12 +309,13 @@ splitHsInstDeclTy inst_ty where split_tau tvs cxt (HsPredTy (HsClassP cls tys)) = (tvs, cxt, cls, tys) split_tau tvs cxt (HsParTy (L _ ty)) = split_tau tvs cxt ty + split_tau _ _ _ = pprPanic "splitHsInstDeclTy" (ppr inst_ty) -- Splits HsType into the (init, last) parts -- Breaks up any parens in the result type: -- splitHsFunType (a -> (b -> c)) = ([a,b], c) splitHsFunType :: LHsType name -> ([LHsType name], LHsType name) -splitHsFunType (L l (HsFunTy x y)) = (x:args, res) +splitHsFunType (L _ (HsFunTy x y)) = (x:args, res) where (args, res) = splitHsFunType y splitHsFunType (L _ (HsParTy ty)) = splitHsFunType ty @@ -258,25 +329,24 @@ splitHsFunType other = ([], other) %* * %************************************************************************ -NB: these types get printed into interface files, so - don't change the printing format lightly - \begin{code} instance (OutputableBndr name) => Outputable (HsType name) where ppr ty = pprHsType ty instance (Outputable name) => Outputable (HsTyVarBndr name) where - ppr (UserTyVar name) = ppr name - ppr (KindedTyVar name kind) = pprHsTyVarBndr name kind + ppr (UserTyVar name _) = ppr name + ppr (KindedTyVar name kind) = hsep [ppr name, dcolon, pprParendKind kind] 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] + ppr (HsClassP clas tys) = ppr clas <+> hsep (map pprLHsType tys) + ppr (HsEqualP t1 t2) = hsep [pprLHsType t1, ptext (sLit "~"), + pprLHsType t2] + ppr (HsIParam n ty) = hsep [ppr n, dcolon, ppr ty] -pprHsTyVarBndr :: Outputable name => name -> Kind -> SDoc -pprHsTyVarBndr name kind | isLiftedTypeKind kind = ppr name - | otherwise = hsep [ppr name, dcolon, pprParendKind kind] +pprLHsType :: OutputableBndr name => LHsType name -> SDoc +pprLHsType = pprParendHsType . unLoc +pprHsForAll :: OutputableBndr name => HsExplicitFlag -> [LHsTyVarBndr name] -> LHsContext name -> SDoc pprHsForAll exp tvs cxt | show_forall = forall_part <+> pprHsContext (unLoc cxt) | otherwise = pprHsContext (unLoc cxt) @@ -284,24 +354,52 @@ pprHsForAll exp tvs cxt 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 + forall_part = ptext (sLit "forall") <+> interppSP tvs <> dot pprHsContext :: (OutputableBndr name) => HsContext name -> SDoc -pprHsContext [] = empty -pprHsContext cxt = ppr_hs_context cxt <+> ptext SLIT("=>") - +pprHsContext [] = empty +pprHsContext [L _ pred] + | noParenHsPred pred = ppr pred <+> ptext (sLit "=>") +pprHsContext cxt = ppr_hs_context cxt <+> ptext (sLit "=>") + +noParenHsPred :: HsPred name -> Bool +-- c.f. TypeRep.noParenPred +noParenHsPred (HsClassP {}) = True +noParenHsPred (HsEqualP {}) = True +noParenHsPred (HsIParam {}) = False + +ppr_hs_context :: (OutputableBndr name) => HsContext name -> SDoc ppr_hs_context [] = empty ppr_hs_context cxt = parens (interpp'SP cxt) + +pprConDeclFields :: OutputableBndr name => [ConDeclField name] -> SDoc +pprConDeclFields fields = braces (sep (punctuate comma (map ppr_fld fields))) + where + ppr_fld (ConDeclField { cd_fld_name = n, cd_fld_type = ty, + cd_fld_doc = doc }) + = ppr n <+> dcolon <+> ppr ty <+> ppr_mbDoc doc \end{code} +Note [Printing KindedTyVars] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Trac #3830 reminded me that we should really only print the kind +signature on a KindedTyVar if the kind signature was put there by the +programmer. During kind inference GHC now adds a PostTcKind to UserTyVars, +rather than converting to KindedTyVars as before. + +(As it happens, the message in #3830 comes out a different way now, +and the problem doesn't show up; but having the flag on a KindedTyVar +seems like the Right Thing anyway.) + \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 +pREC_TOP, pREC_FUN, pREC_OP, pREC_CON :: Int +pREC_TOP = 0 -- type in ParseIface.y +pREC_FUN = 1 -- btype in ParseIface.y + -- Used for LH arg of (->) +pREC_OP = 2 -- Used for arg of any infix operator + -- (we don't keep their fixities around) +pREC_CON = 3 -- Used for arg of type applicn: + -- always parenthesise unless atomic maybeParen :: Int -- Precedence of context -> Int -- Precedence of top-level operator @@ -320,26 +418,31 @@ pprParendHsType ty = ppr_mono_ty pREC_CON ty -- (a) Remove outermost HsParTy parens -- (b) Drop top-level for-all type variables in user style -- since they are implicit in Haskell +prepare :: PprStyle -> HsType name -> HsType name prepare sty (HsParTy ty) = prepare sty (unLoc ty) -prepare sty ty = ty +prepare _ ty = ty +ppr_mono_lty :: (OutputableBndr name) => Int -> LHsType name -> SDoc ppr_mono_lty ctxt_prec ty = ppr_mono_ty ctxt_prec (unLoc ty) +ppr_mono_ty :: (OutputableBndr name) => Int -> HsType name -> SDoc 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 _ (HsBangTy b ty) = ppr b <> ppr ty +ppr_mono_ty _ (HsQuasiQuoteTy qq) = ppr qq +ppr_mono_ty _ (HsRecTy flds) = pprConDeclFields flds +ppr_mono_ty _ (HsTyVar name) = ppr name +ppr_mono_ty prec (HsFunTy ty1 ty2) = ppr_fun_ty prec ty1 ty2 +ppr_mono_ty _ (HsTupleTy con tys) = tupleParens con (interpp'SP tys) +ppr_mono_ty _ (HsKindSig ty kind) = parens (ppr_mono_lty pREC_TOP ty <+> dcolon <+> pprKind kind) +ppr_mono_ty _ (HsListTy ty) = brackets (ppr_mono_lty pREC_TOP ty) +ppr_mono_ty _ (HsPArrTy ty) = pabrackets (ppr_mono_lty pREC_TOP ty) +ppr_mono_ty _ (HsPredTy pred) = ppr pred +ppr_mono_ty _ (HsNumTy n) = integer n -- generics only +ppr_mono_ty _ (HsSpliceTy s _ _) = pprSplice s +ppr_mono_ty _ (HsCoreTy ty) = ppr ty ppr_mono_ty ctxt_prec (HsAppTy fun_ty arg_ty) = maybeParen ctxt_prec pREC_CON $ @@ -349,22 +452,30 @@ 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) +ppr_mono_ty _ (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_mono_ty ctxt_prec (HsDocTy ty doc) + = maybeParen ctxt_prec pREC_OP $ + ppr_mono_lty pREC_OP ty <+> ppr (unLoc doc) + -- we pretty print Haddock comments on types as if they were + -- postfix operators + -------------------------- +ppr_fun_ty :: (OutputableBndr name) => Int -> LHsType name -> LHsType name -> SDoc ppr_fun_ty ctxt_prec ty1 ty2 = let p1 = ppr_mono_lty pREC_FUN ty1 p2 = ppr_mono_lty pREC_TOP ty2 in maybeParen ctxt_prec pREC_FUN $ - sep [p1, ptext SLIT("->") <+> p2] + sep [p1, ptext (sLit "->") <+> p2] -------------------------- -pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]") +pabrackets :: SDoc -> SDoc +pabrackets p = ptext (sLit "[:") <> p <> ptext (sLit ":]") \end{code}