HsConPatDetails, hsConPatArgs,
HsRecFields(..), HsRecField(..), hsRecFields,
- HsQuasiQuote(..),
-
mkPrefixConPat, mkCharLitPat, mkNilPat, mkCoPat, mkCoPatCoI,
- isBangHsBind,
+ isBangHsBind, hsPatNeedsParens,
patsAreAllCons, isConPat, isSigPat, isWildPat,
- patsAreAllLits, isLitPat, isIrrefutableHsPat
- ) where
+ patsAreAllLits, isLitPat, isIrrefutableHsPat,
-#include "HsVersions.h"
+ pprParendLPat
+ ) where
import {-# SOURCE #-} HsExpr (SyntaxExpr, LHsExpr, pprLExpr)
\begin{code}
data HsRecFields id arg -- A bunch of record fields
-- { x = 3, y = True }
- -- Used for both expressiona and patterns
+ -- Used for both expressions and patterns
= HsRecFields { rec_flds :: [HsRecField id arg],
- rec_dotdot :: Maybe Int }
- -- Nothing => the normal case
- -- Just n => the group uses ".." notation,
- -- and the first n elts of rec_flds
- -- were the user-written ones
- -- (In the latter case, the remaining elts of
- -- rec_flds are the non-user-written ones)
+ rec_dotdot :: Maybe Int } -- Note [DotDot fields]
+
+-- Note [DotDot fields]
+-- ~~~~~~~~~~~~~~~~~~~~
+-- The rec_dotdot field means this:
+-- Nothing => the normal case
+-- Just n => the group uses ".." notation,
+--
+-- In the latter case:
+--
+-- *before* renamer: rec_flds are exactly the n user-written fields
+--
+-- *after* renamer: rec_flds includes *all* fields, with
+-- the first 'n' being the user-written ones
+-- and the remainder being 'filled in' implicitly
data HsRecField id arg = HsRecField {
hsRecFieldId :: Located id,
- hsRecFieldArg :: arg,
+ hsRecFieldArg :: arg, -- Filled in by renamer
hsRecPun :: Bool -- Note [Punning]
}
-- If you write T { x, y = v+1 }, the HsRecFields will be
-- HsRecField x x True ...
-- HsRecField y (v+1) False ...
--- That is, for "punned" field x is immediately expanded to x=x
--- but with a punning flag so we can detect it later
+-- That is, for "punned" field x is expanded (in the renamer)
+-- to x=x; but with a punning flag so we can detect it later
-- (e.g. when pretty printing)
+--
+-- If the original field was qualified, we un-qualify it, thus
+-- T { A.x } means T { A.x = x }
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
-\end{code}
-
-
%************************************************************************
%* *
%* Printing patterns
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 (ParPat pat) = parens (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)
pprPat (TuplePat pats bx _) = tupleParens bx (interpp'SP pats)
pprLHsBinds 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)
ppr (HsRecFields { rec_flds = flds, rec_dotdot = Just n })
= braces (fsep (punctuate comma (map ppr (take n flds) ++ [dotdot])))
where
- dotdot = ptext SLIT("..") <+> ifPprDebug (ppr (drop n flds))
+ dotdot = ptext (sLit "..") <+> ifPprDebug (ppr (drop n flds))
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
--
pabrackets :: SDoc -> SDoc
-pabrackets p = ptext SLIT("[:") <> p <> ptext SLIT(":]")
+pabrackets p = ptext (sLit "[:") <> p <> ptext (sLit ":]")
\end{code}
mkCoPatCoI :: CoercionI -> Pat id -> Type -> Pat id
mkCoPatCoI IdCo pat _ = pat
-mkCoPatCoI (ACo co) pat ty = mkCoPat (WpCo co) pat ty
+mkCoPatCoI (ACo co) pat ty = mkCoPat (WpCast co) pat ty
\end{code}
isBangHsBind (PatBind { pat_lhs = L _ (BangPat _) }) = True
isBangHsBind _ = False
-isIrrefutableHsPat :: LPat id -> Bool
+isIrrefutableHsPat :: OutputableBndr id => LPat id -> Bool
-- (isIrrefutableHsPat p) is true if matching against p cannot fail,
-- in the sense of falling through to the next pattern.
-- (NB: this is not quite the same as the (silly) defn
isIrrefutableHsPat pat
= go pat
where
- go (L _ pat) = go1 pat
+ go (L _ pat) = go1 pat
- go1 (WildPat _) = True
- go1 (VarPat _) = True
- go1 (VarPatOut _ _) = True
- go1 (LazyPat _) = True
+ go1 (WildPat {}) = True
+ go1 (VarPat {}) = True
+ go1 (VarPatOut {}) = True
+ go1 (LazyPat {}) = True
go1 (BangPat pat) = go pat
go1 (CoPat _ pat _) = go1 pat
go1 (ParPat pat) = go pat
go1 (SigPatIn pat _) = go pat
go1 (SigPatOut pat _) = go pat
go1 (TuplePat pats _ _) = all go pats
- go1 (ListPat _ _) = False
- go1 (PArrPat _ _) = False -- ?
+ go1 (ListPat {}) = False
+ go1 (PArrPat {}) = False -- ?
- go1 (ConPatIn _ _) = False -- Conservative
+ go1 (ConPatIn {}) = False -- Conservative
go1 (ConPatOut{ pat_con = L _ con, pat_args = details })
= isProductTyCon (dataConTyCon con)
&& all go (hsConPatArgs details)
- go1 (LitPat _) = False
- go1 (NPat _ _ _) = False
- go1 (NPlusKPat _ _ _ _) = False
-
- go1 (TypePat _) = panic "isIrrefutableHsPat: type pattern"
+ go1 (LitPat {}) = False
+ go1 (NPat {}) = False
+ go1 (NPlusKPat {}) = False
+
+ go1 (QuasiQuotePat {}) = urk pat -- Gotten rid of by renamer, before
+ -- isIrrefutablePat is called
+ go1 (TypePat {}) = urk pat
+
+ urk pat = pprPanic "isIrrefutableHsPat:" (ppr pat)
+
+hsPatNeedsParens :: Pat a -> Bool
+hsPatNeedsParens (WildPat {}) = False
+hsPatNeedsParens (VarPat {}) = False
+hsPatNeedsParens (VarPatOut {}) = True
+hsPatNeedsParens (LazyPat {}) = False
+hsPatNeedsParens (BangPat {}) = False
+hsPatNeedsParens (CoPat {}) = True
+hsPatNeedsParens (ParPat {}) = False
+hsPatNeedsParens (AsPat {}) = False
+hsPatNeedsParens (ViewPat {}) = True
+hsPatNeedsParens (SigPatIn {}) = True
+hsPatNeedsParens (SigPatOut {}) = True
+hsPatNeedsParens (TuplePat {}) = False
+hsPatNeedsParens (ListPat {}) = False
+hsPatNeedsParens (PArrPat {}) = False
+hsPatNeedsParens (ConPatIn _ ds) = conPatNeedsParens ds
+hsPatNeedsParens (ConPatOut {}) = True
+hsPatNeedsParens (LitPat {}) = False
+hsPatNeedsParens (NPat {}) = False
+hsPatNeedsParens (NPlusKPat {}) = True
+hsPatNeedsParens (QuasiQuotePat {}) = True
+hsPatNeedsParens (TypePat {}) = False
+
+conPatNeedsParens :: HsConDetails a b -> Bool
+conPatNeedsParens (PrefixCon args) = not (null args)
+conPatNeedsParens (InfixCon {}) = False
+conPatNeedsParens (RecCon {}) = False
\end{code}
projects / ghc-hetmet.git / blobdiff