read_nullary_cons
= case nullary_cons of
[] -> []
- [con] -> [nlHsDo DoExpr [bindLex (ident_pat (data_con_str con))]
- (result_expr con [])]
+ [con] -> [nlHsDo DoExpr [bindLex (match_con con)] (result_expr con [])]
_ -> [nlHsApp (nlHsVar choose_RDR)
(nlList (map mk_pair nullary_cons))]
-
+ -- NB For operators the parens around (:=:) are matched by the
+ -- enclosing "parens" call, so here we must match the naked
+ -- data_con_str con
+
+ match_con con | isSym con_str = symbol_pat con_str
+ | otherwise = ident_pat con_str
+ where
+ con_str = data_con_str con
+ -- For nullary constructors we must match Ident s for normal constrs
+ -- and Symbol s for operators
+
mk_pair con = mkLHsTupleExpr [nlHsLit (mkHsString (data_con_str con)),
result_expr con []]
-
+
read_non_nullary_con data_con
| is_infix = mk_parser infix_prec infix_stmts body
| is_record = mk_parser record_prec record_stmts body
pats_etc data_con
| nullary_con = -- skip the showParen junk...
ASSERT(null bs_needed)
- ([nlWildPat, con_pat], mk_showString_app con_str)
+ ([nlWildPat, con_pat], mk_showString_app op_con_str)
| otherwise =
([a_Pat, con_pat],
showParen_Expr (nlHsPar (genOpApp a_Expr ge_RDR (nlHsLit (HsInt con_prec_plus_one))))
gfoldl_RDR, gunfold_RDR, toConstr_RDR, dataTypeOf_RDR, mkConstr_RDR,
mkDataType_RDR, conIndex_RDR, prefix_RDR, infix_RDR,
- dataCast1_RDR, dataCast2_RDR, gcast1_RDR, gcast2_RDR :: RdrName
-gfoldl_RDR = varQual_RDR gENERICS (fsLit "gfoldl")
-gunfold_RDR = varQual_RDR gENERICS (fsLit "gunfold")
-toConstr_RDR = varQual_RDR gENERICS (fsLit "toConstr")
-dataTypeOf_RDR = varQual_RDR gENERICS (fsLit "dataTypeOf")
-dataCast1_RDR = varQual_RDR gENERICS (fsLit "dataCast1")
-dataCast2_RDR = varQual_RDR gENERICS (fsLit "dataCast2")
-gcast1_RDR = varQual_RDR tYPEABLE (fsLit "gcast1")
-gcast2_RDR = varQual_RDR tYPEABLE (fsLit "gcast2")
-mkConstr_RDR = varQual_RDR gENERICS (fsLit "mkConstr")
-mkDataType_RDR = varQual_RDR gENERICS (fsLit "mkDataType")
-conIndex_RDR = varQual_RDR gENERICS (fsLit "constrIndex")
+ dataCast1_RDR, dataCast2_RDR, gcast1_RDR, gcast2_RDR,
+ constr_RDR, dataType_RDR :: RdrName
+gfoldl_RDR = varQual_RDR gENERICS (fsLit "gfoldl")
+gunfold_RDR = varQual_RDR gENERICS (fsLit "gunfold")
+toConstr_RDR = varQual_RDR gENERICS (fsLit "toConstr")
+dataTypeOf_RDR = varQual_RDR gENERICS (fsLit "dataTypeOf")
+dataCast1_RDR = varQual_RDR gENERICS (fsLit "dataCast1")
+dataCast2_RDR = varQual_RDR gENERICS (fsLit "dataCast2")
+gcast1_RDR = varQual_RDR tYPEABLE (fsLit "gcast1")
+gcast2_RDR = varQual_RDR tYPEABLE (fsLit "gcast2")
+mkConstr_RDR = varQual_RDR gENERICS (fsLit "mkConstr")
+constr_RDR = tcQual_RDR gENERICS (fsLit "Constr")
+mkDataType_RDR = varQual_RDR gENERICS (fsLit "mkDataType")
+dataType_RDR = tcQual_RDR gENERICS (fsLit "DataType")
+conIndex_RDR = varQual_RDR gENERICS (fsLit "constrIndex")
prefix_RDR = dataQual_RDR gENERICS (fsLit "Prefix")
infix_RDR = dataQual_RDR gENERICS (fsLit "Infix")
\end{code}
= (unitBag fmap_bind, [])
where
data_cons = tyConDataCons tycon
-
- fmap_bind = L loc $ mkFunBind (L loc fmap_RDR) (map fmap_eqn data_cons)
+ fmap_bind = L loc $ mkFunBind (L loc fmap_RDR) eqns
+
fmap_eqn con = evalState (match_for_con [f_Pat] con parts) bs_RDRs
where
parts = foldDataConArgs ft_fmap con
+ -- Catch-all eqn looks like fmap _ _ = error "impossible"
+ -- It's needed if there no data cons at all
+ eqns | null data_cons = [mkSimpleMatch [nlWildPat, nlWildPat]
+ (error_Expr "Void fmap")]
+ | otherwise = map fmap_eqn data_cons
+
ft_fmap :: FFoldType (LHsExpr RdrName -> State [RdrName] (LHsExpr RdrName))
-- Tricky higher order type; I can't say I fully understand this code :-(
ft_fmap = FT { ft_triv = \x -> return x -- fmap f x = x
where
data_cons = tyConDataCons tycon
- foldr_bind = L loc $ mkFunBind (L loc foldable_foldr_RDR) (map foldr_eqn data_cons)
+ foldr_bind = L loc $ mkFunBind (L loc foldable_foldr_RDR) eqns
+ eqns | null data_cons = [mkSimpleMatch [nlWildPat, nlWildPat, nlWildPat]
+ (error_Expr "Void foldr")]
+ | otherwise = map foldr_eqn data_cons
foldr_eqn con = evalState (match_for_con z_Expr [f_Pat,z_Pat] con parts) bs_RDRs
where
parts = foldDataConArgs ft_foldr con
where
data_cons = tyConDataCons tycon
- traverse_bind = L loc $ mkFunBind (L loc traverse_RDR) (map traverse_eqn data_cons)
+ traverse_bind = L loc $ mkFunBind (L loc traverse_RDR) eqns
+ eqns | null data_cons = [mkSimpleMatch [nlWildPat, nlWildPat]
+ (error_Expr "Void traverse")]
+ | otherwise = map traverse_eqn data_cons
traverse_eqn con = evalState (match_for_con [f_Pat] con parts) bs_RDRs
where
parts = foldDataConArgs ft_trav con
fiddling around.
\begin{code}
-genAuxBind :: SrcSpan -> DerivAuxBind -> LHsBind RdrName
+genAuxBind :: SrcSpan -> DerivAuxBind -> (LHsBind RdrName, LSig RdrName)
genAuxBind loc (GenCon2Tag tycon)
- | lots_of_constructors
- = mk_FunBind loc rdr_name [([], get_tag_rhs)]
-
- | otherwise
- = mk_FunBind loc rdr_name (map mk_stuff (tyConDataCons tycon))
-
+ = (mk_FunBind loc rdr_name eqns,
+ L loc (TypeSig (L loc rdr_name) (L loc sig_ty)))
where
rdr_name = con2tag_RDR tycon
- tvs = map (mkRdrUnqual . getOccName) (tyConTyVars tycon)
- -- We can't use gerRdrName because that makes an Exact RdrName
- -- and we can't put them in the LocalRdrEnv
+ sig_ty = HsCoreTy $
+ mkForAllTys (tyConTyVars tycon) $
+ mkParentType tycon `mkFunTy` intPrimTy
- -- Give a signature to the bound variable, so
- -- that the case expression generated by getTag is
- -- monomorphic. In the push-enter model we get better code.
- get_tag_rhs = L loc $ ExprWithTySig
- (nlHsLam (mkSimpleHsAlt (nlVarPat a_RDR)
- (nlHsApp (nlHsVar getTag_RDR) a_Expr)))
- (noLoc (mkExplicitHsForAllTy (userHsTyVarBndrs (map noLoc tvs))
- (noLoc []) con2tag_ty))
+ lots_of_constructors = tyConFamilySize tycon > 8
+ -- was: mAX_FAMILY_SIZE_FOR_VEC_RETURNS
+ -- but we don't do vectored returns any more.
- con2tag_ty = nlHsTyConApp (getRdrName tycon) (map nlHsTyVar tvs)
- `nlHsFunTy`
- nlHsTyVar (getRdrName intPrimTyCon)
+ eqns | lots_of_constructors = [get_tag_eqn]
+ | otherwise = map mk_eqn (tyConDataCons tycon)
- lots_of_constructors = tyConFamilySize tycon > 8
- -- was: mAX_FAMILY_SIZE_FOR_VEC_RETURNS
- -- but we don't do vectored returns any more.
+ get_tag_eqn = ([nlVarPat a_RDR], nlHsApp (nlHsVar getTag_RDR) a_Expr)
- mk_stuff :: DataCon -> ([LPat RdrName], LHsExpr RdrName)
- mk_stuff con = ([nlWildConPat con],
- nlHsLit (HsIntPrim (toInteger ((dataConTag con) - fIRST_TAG))))
+ mk_eqn :: DataCon -> ([LPat RdrName], LHsExpr RdrName)
+ mk_eqn con = ([nlWildConPat con],
+ nlHsLit (HsIntPrim (toInteger ((dataConTag con) - fIRST_TAG))))
genAuxBind loc (GenTag2Con tycon)
- = mk_FunBind loc rdr_name
+ = ASSERT( null (tyConTyVars tycon) )
+ (mk_FunBind loc rdr_name
[([nlConVarPat intDataCon_RDR [a_RDR]],
- noLoc (ExprWithTySig (nlHsApp (nlHsVar tagToEnum_RDR) a_Expr)
- (nlHsTyVar (getRdrName tycon))))]
+ nlHsApp (nlHsVar tagToEnum_RDR) a_Expr)],
+ L loc (TypeSig (L loc rdr_name) (L loc sig_ty)))
where
+ sig_ty = HsCoreTy $ intTy `mkFunTy` mkParentType tycon
+
rdr_name = tag2con_RDR tycon
genAuxBind loc (GenMaxTag tycon)
- = mkHsVarBind loc rdr_name
- (nlHsApp (nlHsVar intDataCon_RDR) (nlHsLit (HsIntPrim max_tag)))
+ = (mkHsVarBind loc rdr_name rhs,
+ L loc (TypeSig (L loc rdr_name) (L loc sig_ty)))
where
rdr_name = maxtag_RDR tycon
+ sig_ty = HsCoreTy intTy
+ rhs = nlHsApp (nlHsVar intDataCon_RDR) (nlHsLit (HsIntPrim max_tag))
max_tag = case (tyConDataCons tycon) of
data_cons -> toInteger ((length data_cons) - fIRST_TAG)
genAuxBind loc (MkTyCon tycon) -- $dT
- = mkHsVarBind loc (mk_data_type_name tycon)
- ( nlHsVar mkDataType_RDR
- `nlHsApp` nlHsLit (mkHsString (showSDocOneLine (ppr tycon)))
- `nlHsApp` nlList constrs )
+ = (mkHsVarBind loc rdr_name rhs,
+ L loc (TypeSig (L loc rdr_name) sig_ty))
where
- constrs = [nlHsVar (mk_constr_name con) | con <- tyConDataCons tycon]
+ rdr_name = mk_data_type_name tycon
+ sig_ty = nlHsTyVar dataType_RDR
+ constrs = [nlHsVar (mk_constr_name con) | con <- tyConDataCons tycon]
+ rhs = nlHsVar mkDataType_RDR
+ `nlHsApp` nlHsLit (mkHsString (showSDocOneLine (ppr tycon)))
+ `nlHsApp` nlList constrs
genAuxBind loc (MkDataCon dc) -- $cT1 etc
- = mkHsVarBind loc (mk_constr_name dc)
- (nlHsApps mkConstr_RDR constr_args)
+ = (mkHsVarBind loc rdr_name rhs,
+ L loc (TypeSig (L loc rdr_name) sig_ty))
where
+ rdr_name = mk_constr_name dc
+ sig_ty = nlHsTyVar constr_RDR
+ rhs = nlHsApps mkConstr_RDR constr_args
+
constr_args
= [ -- nlHsIntLit (toInteger (dataConTag dc)), -- Tag
nlHsVar (mk_data_type_name (dataConTyCon dc)), -- DataType
mk_constr_name :: DataCon -> RdrName -- "$cC"
mk_constr_name con = mkAuxBinderName (dataConName con) mkDataCOcc
+
+mkParentType :: TyCon -> Type
+-- Turn the representation tycon of a family into
+-- a use of its family constructor
+mkParentType tc
+ = case tyConFamInst_maybe tc of
+ Nothing -> mkTyConApp tc (mkTyVarTys (tyConTyVars tc))
+ Just (fam_tc,tys) -> mkTyConApp fam_tc tys
\end{code}
%************************************************************************
-- impossible_Expr is used in case RHSs that should never happen.
-- We generate these to keep the desugarer from complaining that they *might* happen!
--- impossible_Expr :: LHsExpr RdrName
--- impossible_Expr = nlHsApp (nlHsVar error_RDR) (nlHsLit (mkHsString "Urk! in TcGenDeriv"))
+error_Expr :: String -> LHsExpr RdrName
+error_Expr string = nlHsApp (nlHsVar error_RDR) (nlHsLit (mkHsString string))
-- illegal_Expr is used when signalling error conditions in the RHS of a derived
-- method. It is currently only used by Enum.{succ,pred}
projects / ghc-hetmet.git / blobdiff