X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FhsSyn%2FHsPat.lhs;h=1bf0aa828148bd7cf020f820e883c7a8bf2465e7;hb=2fc5aa708982a414235d3aff68dea4329b546063;hp=c8867661d526d2546d912eeb348c2552a269d761;hpb=f7df28a48a9d2901d9e27e0e9970b3f692bc9b3f;p=ghc-hetmet.git diff --git a/compiler/hsSyn/HsPat.lhs b/compiler/hsSyn/HsPat.lhs index c886766..1bf0aa8 100644 --- a/compiler/hsSyn/HsPat.lhs +++ b/compiler/hsSyn/HsPat.lhs @@ -11,6 +11,7 @@ -- any warnings in the module. See -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings -- for details +{-# LANGUAGE DeriveDataTypeable #-} module HsPat ( Pat(..), InPat, OutPat, LPat, @@ -19,13 +20,12 @@ module HsPat ( HsConPatDetails, hsConPatArgs, HsRecFields(..), HsRecField(..), hsRecFields, - HsQuasiQuote(..), + mkPrefixConPat, mkCharLitPat, mkNilPat, - mkPrefixConPat, mkCharLitPat, mkNilPat, mkCoPat, mkCoPatCoI, + isBangHsBind, isBangLPat, hsPatNeedsParens, + isIrrefutableHsPat, - isBangHsBind, hsPatNeedsParens, - patsAreAllCons, isConPat, isSigPat, isWildPat, - patsAreAllLits, isLitPat, isIrrefutableHsPat + pprParendLPat ) where import {-# SOURCE #-} HsExpr (SyntaxExpr, LHsExpr, pprLExpr) @@ -36,7 +36,6 @@ import HsLit import HsTypes import BasicTypes -- others: -import Coercion import PprCore ( {- instance OutputableBndr TyVar -} ) import TysWiredIn import Var @@ -46,6 +45,8 @@ import Outputable import Type import SrcLoc import FastString +-- libraries: +import Data.Data hiding (TyCon) \end{code} @@ -62,7 +63,7 @@ data Pat id -- support hsPatType :: Pat Id -> Type | VarPat id -- Variable - | VarPatOut id (DictBinds id) -- Used only for overloaded Ids; the + | VarPatOut id TcEvBinds -- Used only for overloaded Ids; the -- bindings give its overloaded instances | LazyPat (LPat id) -- Lazy pattern | AsPat (Located id) (LPat id) -- As pattern @@ -98,10 +99,10 @@ data Pat id | ConPatOut { pat_con :: Located DataCon, pat_tvs :: [TyVar], -- Existentially bound type variables (tyvars only) - pat_dicts :: [id], -- Ditto *coercion variables* and *dictionaries* + pat_dicts :: [EvVar], -- Ditto *coercion variables* and *dictionaries* -- One reason for putting coercion variable here, I think, -- is to ensure their kinds are zonked - pat_binds :: DictBinds id, -- Bindings involving those dictionaries + pat_binds :: TcEvBinds, -- Bindings involving those dictionaries pat_args :: HsConPatDetails id, pat_ty :: Type -- The type of the pattern } @@ -145,12 +146,13 @@ data Pat id Type ------------ Pattern coercions (translation only) --------------- - | CoPat HsWrapper -- If co::t1 -> t2, p::t2, + | CoPat HsWrapper -- If co :: t1 ~ t2, p :: t2, -- then (CoPat co p) :: t1 (Pat id) -- Why not LPat? Ans: existing locn will do Type -- Type of whole pattern, t1 -- During desugaring a (CoPat co pat) turns into a cast with 'co' on -- the scrutinee, followed by a match on 'pat' + deriving (Data, Typeable) \end{code} HsConDetails is use for patterns/expressions *and* for data type declarations @@ -160,6 +162,7 @@ data HsConDetails arg rec = PrefixCon [arg] -- C p1 p2 p3 | RecCon rec -- C { x = p1, y = p2 } | InfixCon arg arg -- p1 `C` p2 + deriving (Data, Typeable) type HsConPatDetails id = HsConDetails (LPat id) (HsRecFields id (LPat id)) @@ -178,6 +181,7 @@ data HsRecFields id arg -- A bunch of record fields -- Used for both expressions and patterns = HsRecFields { rec_flds :: [HsRecField id arg], rec_dotdot :: Maybe Int } -- Note [DotDot fields] + deriving (Data, Typeable) -- Note [DotDot fields] -- ~~~~~~~~~~~~~~~~~~~~ @@ -195,9 +199,9 @@ data HsRecFields id arg -- A bunch of record fields data HsRecField id arg = HsRecField { hsRecFieldId :: Located id, - hsRecFieldArg :: arg, + hsRecFieldArg :: arg, -- Filled in by renamer hsRecPun :: Bool -- Note [Punning] - } + } deriving (Data, Typeable) -- Note [Punning] -- ~~~~~~~~~~~~~~ @@ -215,24 +219,6 @@ hsRecFields :: HsRecFields id arg -> [id] hsRecFields rbinds = map (unLoc . hsRecFieldId) (rec_flds rbinds) \end{code} -\begin{code} -data HsQuasiQuote id = HsQuasiQuote - id - id - SrcSpan - FastString - -instance OutputableBndr id => Outputable (HsQuasiQuote id) where - ppr = ppr_qq - -ppr_qq :: OutputableBndr id => HsQuasiQuote id -> SDoc -ppr_qq (HsQuasiQuote name quoter _ quote) = - char '$' <> brackets (ppr name) <> - ptext (sLit "[:") <> ppr quoter <> ptext (sLit "|") <> - ppr quote <> ptext (sLit "|]") -\end{code} - - %************************************************************************ %* * %* Printing patterns @@ -252,14 +238,30 @@ pprPatBndr var -- Print with type info if -dppr-debug is on else ppr var +pprParendLPat :: (OutputableBndr name) => LPat name -> SDoc +pprParendLPat (L _ p) = pprParendPat p + +pprParendPat :: (OutputableBndr name) => Pat name -> SDoc +pprParendPat p | patNeedsParens p = parens (pprPat p) + | otherwise = pprPat p + +patNeedsParens :: Pat name -> Bool +patNeedsParens (ConPatIn _ d) = not (null (hsConPatArgs d)) +patNeedsParens (ConPatOut { pat_args = d }) = not (null (hsConPatArgs d)) +patNeedsParens (SigPatIn {}) = True +patNeedsParens (SigPatOut {}) = True +patNeedsParens (ViewPat {}) = True +patNeedsParens (CoPat {}) = True +patNeedsParens _ = False + pprPat :: (OutputableBndr name) => Pat name -> SDoc pprPat (VarPat var) = pprPatBndr var -pprPat (VarPatOut var bs) = parens (pprPatBndr var <+> braces (ppr bs)) +pprPat (VarPatOut var bs) = pprPatBndr var <+> braces (ppr bs) pprPat (WildPat _) = char '_' -pprPat (LazyPat pat) = char '~' <> ppr pat -pprPat (BangPat pat) = char '!' <> ppr pat -pprPat (AsPat name pat) = parens (hcat [ppr name, char '@', ppr pat]) -pprPat (ViewPat expr pat _) = parens (hcat [pprLExpr expr, text " -> ", ppr pat]) +pprPat (LazyPat pat) = char '~' <> pprParendLPat pat +pprPat (BangPat pat) = char '!' <> pprParendLPat pat +pprPat (AsPat name pat) = hcat [ppr name, char '@', pprParendLPat pat] +pprPat (ViewPat expr pat _) = hcat [pprLExpr expr, text " -> ", ppr pat] pprPat (ParPat pat) = parens (ppr pat) pprPat (ListPat pats _) = brackets (interpp'SP pats) pprPat (PArrPat pats _) = pabrackets (interpp'SP pats) @@ -272,29 +274,26 @@ pprPat (ConPatOut { pat_con = con, pat_tvs = tvs, pat_dicts = dicts, if debugStyle sty then -- typechecked Pat in an error message, -- and we want to make sure it prints nicely ppr con <+> sep [ hsep (map pprPatBndr tvs) <+> hsep (map pprPatBndr dicts), - pprLHsBinds binds, pprConArgs details] + ppr binds, pprConArgs details] else pprUserCon con details -pprPat (LitPat s) = ppr s +pprPat (LitPat s) = ppr s pprPat (NPat l Nothing _) = ppr l pprPat (NPat l (Just _) _) = char '-' <> ppr l -pprPat (NPlusKPat n k _ _) = hcat [ppr n, char '+', ppr k] -pprPat (QuasiQuotePat (HsQuasiQuote name quoter _ quote)) - = char '$' <> brackets (ppr name) <> - ptext (sLit "[:") <> ppr quoter <> ptext (sLit "|") <> - ppr quote <> ptext (sLit "|]") -pprPat (TypePat ty) = ptext (sLit "{|") <> ppr ty <> ptext (sLit "|}") -pprPat (CoPat co pat _) = parens (pprHsWrapper (ppr pat) co) -pprPat (SigPatIn pat ty) = ppr pat <+> dcolon <+> ppr ty -pprPat (SigPatOut pat ty) = ppr pat <+> dcolon <+> ppr ty +pprPat (NPlusKPat n k _ _) = hcat [ppr n, char '+', ppr k] +pprPat (QuasiQuotePat qq) = ppr qq +pprPat (TypePat ty) = ptext (sLit "{|") <> ppr ty <> ptext (sLit "|}") +pprPat (CoPat co pat _) = pprHsWrapper (ppr pat) co +pprPat (SigPatIn pat ty) = ppr pat <+> dcolon <+> ppr ty +pprPat (SigPatOut pat ty) = ppr pat <+> dcolon <+> ppr ty pprUserCon :: (Outputable con, OutputableBndr id) => con -> HsConPatDetails id -> SDoc pprUserCon c (InfixCon p1 p2) = ppr p1 <+> ppr c <+> ppr p2 pprUserCon c details = ppr c <+> pprConArgs details pprConArgs :: OutputableBndr id => HsConPatDetails id -> SDoc -pprConArgs (PrefixCon pats) = interppSP pats -pprConArgs (InfixCon p1 p2) = interppSP [p1,p2] +pprConArgs (PrefixCon pats) = sep (map pprParendLPat pats) +pprConArgs (InfixCon p1 p2) = sep [pprParendLPat p1, pprParendLPat p2] pprConArgs (RecCon rpats) = ppr rpats instance (OutputableBndr id, Outputable arg) @@ -310,7 +309,7 @@ instance (OutputableBndr id, Outputable arg) => Outputable (HsRecField id arg) where ppr (HsRecField { hsRecFieldId = f, hsRecFieldArg = arg, hsRecPun = pun }) - = ppr f <+> (if pun then empty else equals <+> ppr arg) + = ppr f <+> (ppUnless pun $ equals <+> ppr arg) -- add parallel array brackets around a document -- @@ -330,7 +329,7 @@ mkPrefixConPat :: DataCon -> [OutPat id] -> Type -> OutPat id -- Make a vanilla Prefix constructor pattern mkPrefixConPat dc pats ty = noLoc $ ConPatOut { pat_con = noLoc dc, pat_tvs = [], pat_dicts = [], - pat_binds = emptyLHsBinds, pat_args = PrefixCon pats, + pat_binds = emptyTcEvBinds, pat_args = PrefixCon pats, pat_ty = ty } mkNilPat :: Type -> OutPat id @@ -338,15 +337,6 @@ mkNilPat ty = mkPrefixConPat nilDataCon [] ty mkCharLitPat :: Char -> OutPat id mkCharLitPat c = mkPrefixConPat charDataCon [noLoc $ LitPat (HsCharPrim c)] charTy - -mkCoPat :: HsWrapper -> Pat id -> Type -> Pat id -mkCoPat co pat ty - | isIdHsWrapper co = pat - | otherwise = CoPat co pat ty - -mkCoPatCoI :: CoercionI -> Pat id -> Type -> Pat id -mkCoPatCoI IdCo pat _ = pat -mkCoPatCoI (ACo co) pat ty = mkCoPat (WpCast co) pat ty \end{code} @@ -380,41 +370,15 @@ patterns are treated specially, of course. The 1.3 report defines what ``irrefutable'' and ``failure-free'' patterns are. \begin{code} -isWildPat :: Pat id -> Bool -isWildPat (WildPat _) = True -isWildPat _ = False - -patsAreAllCons :: [Pat id] -> Bool -patsAreAllCons pat_list = all isConPat pat_list - -isConPat :: Pat id -> Bool -isConPat (AsPat _ pat) = isConPat (unLoc pat) -isConPat (ConPatIn {}) = True -isConPat (ConPatOut {}) = True -isConPat (ListPat {}) = True -isConPat (PArrPat {}) = True -isConPat (TuplePat {}) = True -isConPat _ = False - -isSigPat :: Pat id -> Bool -isSigPat (SigPatIn _ _) = True -isSigPat (SigPatOut _ _) = True -isSigPat _ = False - -patsAreAllLits :: [Pat id] -> Bool -patsAreAllLits pat_list = all isLitPat pat_list - -isLitPat :: Pat id -> Bool -isLitPat (AsPat _ pat) = isLitPat (unLoc pat) -isLitPat (LitPat _) = True -isLitPat (NPat _ _ _) = True -isLitPat (NPlusKPat _ _ _ _) = True -isLitPat _ = False +isBangLPat :: LPat id -> Bool +isBangLPat (L _ (BangPat {})) = True +isBangLPat (L _ (ParPat p)) = isBangLPat p +isBangLPat _ = False isBangHsBind :: HsBind id -> Bool -- In this module because HsPat is above HsBinds in the import graph -isBangHsBind (PatBind { pat_lhs = L _ (BangPat _) }) = True -isBangHsBind _ = False +isBangHsBind (PatBind { pat_lhs = p }) = isBangLPat p +isBangHsBind _ = False isIrrefutableHsPat :: OutputableBndr id => LPat id -> Bool -- (isIrrefutableHsPat p) is true if matching against p cannot fail,