DefaultDecl(..), LDefaultDecl, SpliceDecl(..),
ForeignDecl(..), LForeignDecl, ForeignImport(..), ForeignExport(..),
CImportSpec(..), FoType(..),
- ConDecl(..), LConDecl,
+ ConDecl(..), ResType(..), LConDecl,
DeprecDecl(..), LDeprecDecl,
HsGroup(..), emptyRdrGroup, emptyRnGroup, appendGroups,
tcdName, tyClDeclNames, tyClDeclTyVars,
import Class ( FunDep )
import Outputable
import Util ( count )
-import SrcLoc ( Located(..), unLoc )
+import SrcLoc ( Located(..), unLoc, noLoc )
import FastString
\end{code}
-- (only for the 'where' form)
tcdCons :: [LConDecl name], -- Data constructors
- -- For data T a = T1 | T2 a the LConDecls are all ConDecls
- -- For data T a where { T1 :: T a } the LConDecls are all GadtDecls
+ -- For data T a = T1 | T2 a the LConDecls all have ResTyH98
+ -- For data T a where { T1 :: T a } the LConDecls all have ResTyGADT
tcdDerivs :: Maybe [LHsType name]
-- Derivings; Nothing => not specified
-> SDoc
pp_decl_head context thing tyvars
= hsep [pprHsContext context, ppr thing, interppSP tyvars]
-
-pp_condecls cs@(L _ (GadtDecl _ _) : _) -- In GADT syntax
+pp_condecls cs@(L _ ConDecl{ con_res = ResTyGADT _ } : _) -- In GADT syntax
= hang (ptext SLIT("where")) 2 (vcat (map ppr cs))
pp_condecls cs -- In H98 syntax
= equals <+> sep (punctuate (ptext SLIT(" |")) (map ppr cs))
type LConDecl name = Located (ConDecl name)
data ConDecl name
- = ConDecl (Located name) -- Constructor name; this is used for the
- -- DataCon itself, and for the user-callable wrapper Id
-
- [LHsTyVarBndr name] -- Existentially quantified type variables
- (LHsContext name) -- ...and context
- -- If both are empty then there are no existentials
- (HsConDetails name (LBangType name))
-
- | GadtDecl (Located name) -- Constructor name; this is used for the
- -- DataCon itself, and for the user-callable wrapper Id
- (LHsType name) -- Constructor type; it may have HsBangs on the
- -- argument types
+ = ConDecl
+ { con_name :: Located name -- Constructor name; this is used for the
+ -- DataCon itself, and for the user-callable wrapper Id
+
+ , con_explicit :: HsExplicitForAll -- Is there an user-written forall? (cf. HStypes.HsForAllTy)
+
+ , con_qvars :: [LHsTyVarBndr name] -- ResTyH98: the constructor's existential type variables
+ -- ResTyGADT: all the constructor's quantified type variables
+
+ , con_cxt :: LHsContext name -- The context. This *does not* include the
+ -- "stupid theta" which lives only in the TyData decl
+
+ , con_details :: HsConDetails name (LBangType name) -- The main payload
+
+ , con_res :: ResType name -- Result type of the constructor
+ }
+
+data ResType name
+ = ResTyH98 -- Constructor was declared using Haskell 98 syntax
+ | ResTyGADT (LHsType name) -- Constructor was declared using GADT-style syntax,
+ -- and here is its result type
\end{code}
\begin{code}
conDeclsNames cons
= snd (foldl do_one ([], []) cons)
where
- do_one (flds_seen, acc) (ConDecl lname _ _ (RecCon flds))
+ do_one (flds_seen, acc) (ConDecl { con_name = lname, con_details = RecCon flds })
= (map unLoc new_flds ++ flds_seen, lname : [f | f <- new_flds] ++ acc)
where
new_flds = [ f | (f,_) <- flds, not (unLoc f `elem` flds_seen) ]
- do_one (flds_seen, acc) (ConDecl lname _ _ _)
- = (flds_seen, lname:acc)
-
--- gaw 2004
- do_one (flds_seen, acc) (GadtDecl lname _)
- = (flds_seen, lname:acc)
+ do_one (flds_seen, acc) c
+ = (flds_seen, (con_name c):acc)
conDetailsTys details = map getBangType (hsConArgs details)
\end{code}
\begin{code}
instance (OutputableBndr name) => Outputable (ConDecl name) where
- ppr (ConDecl con tvs cxt con_details)
- = sep [pprHsForAll Explicit tvs cxt, ppr_con_details con con_details]
- ppr (GadtDecl con ty)
- = ppr con <+> dcolon <+> ppr ty
-
-ppr_con_details con (InfixCon ty1 ty2)
- = hsep [ppr ty1, pprHsVar con, ppr ty2]
-
--- ConDecls generated by MkIface.ifaceTyThing always have a PrefixCon, even
--- if the constructor is an infix one. This is because in an interface file
--- we don't distinguish between the two. Hence when printing these for the
--- user, we need to parenthesise infix constructor names.
-ppr_con_details con (PrefixCon tys)
- = hsep (pprHsVar con : map ppr tys)
-
-ppr_con_details con (RecCon fields)
- = ppr con <+> braces (sep (punctuate comma (map ppr_field fields)))
+ ppr = pprConDecl
+
+pprConDecl (ConDecl con expl tvs cxt details ResTyH98)
+ = sep [pprHsForAll expl tvs cxt, ppr_details con details]
where
- ppr_field (n, ty) = ppr n <+> dcolon <+> ppr ty
+ ppr_details con (InfixCon t1 t2) = hsep [ppr t1, pprHsVar con, ppr t2]
+ ppr_details con (PrefixCon tys) = hsep (pprHsVar con : map ppr tys)
+ ppr_details con (RecCon fields) = ppr con <+> ppr_fields fields
+
+pprConDecl (ConDecl con expl tvs cxt details (ResTyGADT res_ty))
+ = sep [pprHsForAll expl tvs cxt, ppr con <+> ppr_details details]
+ where
+ ppr_details (PrefixCon arg_tys) = dcolon <+> ppr (foldr mk_fun_ty res_ty arg_tys)
+ ppr_details (RecCon fields) = ppr fields <+> dcolon <+> ppr res_ty
+ ppr_details (PrefixCon _) = pprPanic "pprConDecl" (ppr con)
+
+ mk_fun_ty a b = noLoc (HsFunTy a b)
+ppr_fields fields = braces (sep (punctuate comma (map ppr_field fields)))
+ppr_field (n, ty) = ppr n <+> dcolon <+> ppr ty
\end{code}
%************************************************************************
projects / ghc-hetmet.git / blobdiff