New syntax for GADT-style record declarations, and associated refactoring

[ghc-hetmet.git] / compiler / hsSyn / HsPat.lhs

diff --git a/compiler/hsSyn/HsPat.lhs b/compiler/hsSyn/HsPat.lhs
index 266cff2..9e954a6 100644 (file)
--- a/compiler/hsSyn/HsPat.lhs
+++ b/compiler/hsSyn/HsPat.lhs
@@ -5,7 +5,7 @@
 \section[PatSyntax]{Abstract Haskell syntax---patterns}
 
 \begin{code}
-{-# OPTIONS -w #-}
+{-# OPTIONS -fno-warn-incomplete-patterns #-}
 -- The above warning supression flag is a temporary kludge.
 -- While working on this module you are encouraged to remove it and fix
 -- any warnings in the module. See
@@ -28,15 +28,12 @@ module HsPat (
        patsAreAllLits, isLitPat, isIrrefutableHsPat
     ) where
 
-#include "HsVersions.h"
-
 import {-# SOURCE #-} HsExpr           (SyntaxExpr, LHsExpr, pprLExpr)
 
 -- friends:
 import HsBinds
 import HsLit
 import HsTypes
-import HsDoc
 import BasicTypes
 -- others:
 import Coercion
@@ -213,6 +210,15 @@ data HsQuasiQuote id = HsQuasiQuote
                       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}
 
 
@@ -264,16 +270,18 @@ 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("|}")
+      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
 
+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 (RecCon rpats)   = ppr rpats
@@ -285,7 +293,7 @@ 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
@@ -296,7 +304,7 @@ instance (OutputableBndr id, Outputable 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}
 
 
@@ -326,8 +334,8 @@ mkCoPat co pat ty
   | otherwise        = CoPat co pat ty
 
 mkCoPatCoI :: CoercionI -> Pat id -> Type -> Pat id
-mkCoPatCoI IdCo     pat ty = pat
-mkCoPatCoI (ACo co) pat ty = mkCoPat (WpCo co) pat ty
+mkCoPatCoI IdCo     pat _  = pat
+mkCoPatCoI (ACo co) pat ty = mkCoPat (WpCast co) pat ty
 \end{code}
 
 
@@ -361,39 +369,43 @@ 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 other              = False
+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 other          = False
+isConPat _               = False
 
+isSigPat :: Pat id -> Bool
 isSigPat (SigPatIn _ _)  = True
 isSigPat (SigPatOut _ _) = True
-isSigPat other          = False
+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 other                 = False
+isLitPat _                      = False
 
 isBangHsBind :: HsBind id -> Bool
 -- In this module because HsPat is above HsBinds in the import graph
-isBangHsBind (PatBind { pat_lhs = L _ (BangPat p) }) = True
-isBangHsBind bind                                   = False
+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
@@ -410,7 +422,7 @@ isIrrefutableHsPat pat
     go1 (WildPat _)         = True
     go1 (VarPat _)          = True
     go1 (VarPatOut _ _)     = True
-    go1 (LazyPat pat)       = True
+    go1 (LazyPat _)         = True
     go1 (BangPat pat)       = go pat
     go1 (CoPat _ pat _)     = go1 pat
     go1 (ParPat pat)        = go pat
@@ -419,8 +431,8 @@ isIrrefutableHsPat pat
     go1 (SigPatIn pat _)    = go pat
     go1 (SigPatOut pat _)   = go pat
     go1 (TuplePat pats _ _) = all go pats
-    go1 (ListPat pats _)    = False
-    go1 (PArrPat pats _)    = False    -- ?
+    go1 (ListPat _ _)       = False
+    go1 (PArrPat _ _)       = False    -- ?
 
     go1 (ConPatIn _ _) = False -- Conservative
     go1 (ConPatOut{ pat_con = L _ con, pat_args = details }) 
@@ -431,6 +443,10 @@ isIrrefutableHsPat pat
     go1 (NPat _ _ _)      = False
     go1 (NPlusKPat _ _ _ _) = False
 
-    go1 (TypePat _)   = panic "isIrrefutableHsPat: type pattern"
+    go1 (QuasiQuotePat {}) = urk pat   -- Gotten rid of by renamer, before
+                                       -- isIrrefutablePat is called
+    go1 (TypePat {})       = urk pat
+
+    urk pat = pprPanic "isIrrefutableHsPat:" (ppr pat)
 \end{code}