import HsSyn ( InPat(..), HsExpr(..), MonoBinds(..),
Match(..), GRHSs(..), Stmt(..), HsLit(..),
- HsBinds(..), HsType(..), HsMatchContext(..),
- unguardedRHS, mkSimpleMatch, mkMonoBind, andMonoBindList
+ HsBinds(..), HsType(..), HsDoContext(..),
+ unguardedRHS, mkSimpleMatch, mkMonoBind, andMonoBindList, placeHolderType
)
-import RdrHsSyn ( mkHsOpApp, RdrNameMonoBinds, RdrNameHsExpr, RdrNamePat )
import RdrName ( RdrName, mkUnqual )
+import RdrHsSyn ( mkHsOpApp, RdrNameMonoBinds, RdrNameHsExpr, RdrNamePat, mkHsDo )
import BasicTypes ( RecFlag(..), Fixity(..), FixityDirection(..)
- , maxPrecedence, defaultFixity
+ , maxPrecedence
, Boxity(..)
)
-import FieldLabel ( fieldLabelName )
+import FieldLabel ( FieldLabel, fieldLabelName )
import DataCon ( isNullaryDataCon, dataConTag,
dataConOrigArgTys, dataConSourceArity, fIRST_TAG,
DataCon,
isDataSymOcc, isSymOcc
)
+import HscTypes ( FixityEnv, lookupFixity )
import PrelInfo -- Lots of RdrNames
import SrcLoc ( generatedSrcLoc, SrcLoc )
import TyCon ( TyCon, isNewTyCon, tyConDataCons, isEnumerationTyCon,
maybeTyConSingleCon, tyConFamilySize
)
-import Type ( isUnLiftedType, Type )
+import TcType ( isUnLiftedType, tcEqType, Type )
import TysPrim ( charPrimTy, intPrimTy, wordPrimTy, addrPrimTy,
floatPrimTy, doublePrimTy
)
-import Util ( mapAccumL, zipEqual, zipWithEqual,
+import Util ( mapAccumL, zipEqual, zipWithEqual, isSingleton,
zipWith3Equal, nOfThem )
import Panic ( panic, assertPanic )
-import Maybes ( maybeToBool, orElse )
+import Maybes ( maybeToBool )
+import Char ( ord, isAlpha )
import Constants
import List ( partition, intersperse )
-
-#if __GLASGOW_HASKELL__ >= 404
-import GlaExts ( fromInt )
-#endif
+import FastString
\end{code}
%************************************************************************
else -- calc. and compare the tags
[([a_Pat, b_Pat],
untag_Expr tycon [(a_RDR,ah_RDR), (b_RDR,bh_RDR)]
- (cmp_tags_Expr eqH_Int_RDR ah_RDR bh_RDR true_Expr false_Expr))]
+ (genOpApp (HsVar ah_RDR) eqH_Int_RDR (HsVar bh_RDR)))]
in
mk_FunMonoBind tycon_loc eq_RDR ((map pats_etc nonnullary_cons) ++ rest)
`AndMonoBinds`
mk_easy_FunMonoBind tycon_loc ne_RDR [a_Pat, b_Pat] [] (
- HsApp (HsVar not_RDR) (HsPar (mk_easy_App eq_RDR [a_RDR, b_RDR])))
+ HsApp (HsVar not_RDR) (HsPar (mkHsVarApps eq_RDR [a_RDR, b_RDR])))
where
------------------------------------------------------------------
pats_etc data_con
cmp_eq =
mk_FunMonoBind tycon_loc
cmp_eq_RDR
- (if null nonnullary_cons && (length nullary_cons == 1) then
+ (if null nonnullary_cons && isSingleton nullary_cons then
-- catch this specially to avoid warnings
-- about overlapping patterns from the desugarer.
let
else
map pats_etc nonnullary_cons ++
-- leave out wildcards to silence desugarer.
- (if length tycon_data_cons == 1 then
+ (if isSingleton tycon_data_cons then
[]
else
[([WildPatIn, WildPatIn], default_rhs)]))
-- inexhaustive patterns
| otherwise = eqTag_Expr -- Some nullary constructors;
-- Tags are equal, no args => return EQ
- --------------------------------------------------------------------
-
-{- Not necessary: the default decls in PrelBase handle these
-
-defaulted = foldr1 AndMonoBinds [lt, le, ge, gt, max_, min_]
-
-lt = mk_easy_FunMonoBind generatedSrcLoc lt_RDR [a_Pat, b_Pat] [] (
- compare_Case true_Expr false_Expr false_Expr a_Expr b_Expr)
-le = mk_easy_FunMonoBind generatedSrcLoc le_RDR [a_Pat, b_Pat] [] (
- compare_Case true_Expr true_Expr false_Expr a_Expr b_Expr)
-ge = mk_easy_FunMonoBind generatedSrcLoc ge_RDR [a_Pat, b_Pat] [] (
- compare_Case false_Expr true_Expr true_Expr a_Expr b_Expr)
-gt = mk_easy_FunMonoBind generatedSrcLoc gt_RDR [a_Pat, b_Pat] [] (
- compare_Case false_Expr false_Expr true_Expr a_Expr b_Expr)
-
-max_ = mk_easy_FunMonoBind generatedSrcLoc max_RDR [a_Pat, b_Pat] [] (
- compare_Case b_Expr a_Expr a_Expr a_Expr b_Expr)
-min_ = mk_easy_FunMonoBind generatedSrcLoc min_RDR [a_Pat, b_Pat] [] (
- compare_Case a_Expr b_Expr b_Expr a_Expr b_Expr)
--}
\end{code}
%************************************************************************
succ_enum
= mk_easy_FunMonoBind tycon_loc succ_RDR [a_Pat] [] $
untag_Expr tycon [(a_RDR, ah_RDR)] $
- HsIf (HsApp (HsApp (HsVar eq_RDR)
- (HsVar (maxtag_RDR tycon)))
- (mk_easy_App mkInt_RDR [ah_RDR]))
+ HsIf (mkHsApps eq_RDR [HsVar (maxtag_RDR tycon),
+ mkHsVarApps mkInt_RDR [ah_RDR]])
(illegal_Expr "succ" occ_nm "tried to take `succ' of last tag in enumeration")
(HsApp (HsVar (tag2con_RDR tycon))
- (HsApp (HsApp (HsVar plus_RDR)
- (mk_easy_App mkInt_RDR [ah_RDR]))
- (HsLit (HsInt 1))))
+ (mkHsApps plus_RDR [mkHsVarApps mkInt_RDR [ah_RDR],
+ mkHsIntLit 1]))
tycon_loc
pred_enum
= mk_easy_FunMonoBind tycon_loc pred_RDR [a_Pat] [] $
untag_Expr tycon [(a_RDR, ah_RDR)] $
- HsIf (HsApp (HsApp (HsVar eq_RDR) (HsLit (HsInt 0)))
- (mk_easy_App mkInt_RDR [ah_RDR]))
+ HsIf (mkHsApps eq_RDR [mkHsIntLit 0,
+ mkHsVarApps mkInt_RDR [ah_RDR]])
(illegal_Expr "pred" occ_nm "tried to take `pred' of first tag in enumeration")
(HsApp (HsVar (tag2con_RDR tycon))
- (HsApp (HsApp (HsVar plus_RDR)
- (mk_easy_App mkInt_RDR [ah_RDR]))
- (HsLit (HsInt (-1)))))
+ (mkHsApps plus_RDR [mkHsVarApps mkInt_RDR [ah_RDR],
+ HsLit (HsInt (-1))]))
tycon_loc
to_enum
= mk_easy_FunMonoBind tycon_loc toEnum_RDR [a_Pat] [] $
- HsIf (HsApp (HsApp
- (HsVar and_RDR)
- (HsApp (HsApp (HsVar ge_RDR)
- (HsVar a_RDR))
- (HsLit (HsInt 0))))
- (HsApp (HsApp (HsVar le_RDR)
- (HsVar a_RDR))
- (HsVar (maxtag_RDR tycon))))
- (mk_easy_App (tag2con_RDR tycon) [a_RDR])
+ HsIf (mkHsApps and_RDR
+ [mkHsApps ge_RDR [HsVar a_RDR, mkHsIntLit 0],
+ mkHsApps le_RDR [HsVar a_RDR, HsVar (maxtag_RDR tycon)]])
+ (mkHsVarApps (tag2con_RDR tycon) [a_RDR])
(illegal_toEnum_tag occ_nm (maxtag_RDR tycon))
tycon_loc
enum_from
= mk_easy_FunMonoBind tycon_loc enumFrom_RDR [a_Pat] [] $
untag_Expr tycon [(a_RDR, ah_RDR)] $
- HsApp (mk_easy_App map_RDR [tag2con_RDR tycon]) $
- HsPar (enum_from_to_Expr
- (mk_easy_App mkInt_RDR [ah_RDR])
- (HsVar (maxtag_RDR tycon)))
+ mkHsApps map_RDR
+ [HsVar (tag2con_RDR tycon),
+ HsPar (enum_from_to_Expr
+ (mkHsVarApps mkInt_RDR [ah_RDR])
+ (HsVar (maxtag_RDR tycon)))]
enum_from_then
= mk_easy_FunMonoBind tycon_loc enumFromThen_RDR [a_Pat, b_Pat] [] $
untag_Expr tycon [(a_RDR, ah_RDR), (b_RDR, bh_RDR)] $
- HsApp (mk_easy_App map_RDR [tag2con_RDR tycon]) $
+ HsApp (mkHsVarApps map_RDR [tag2con_RDR tycon]) $
HsPar (enum_from_then_to_Expr
- (mk_easy_App mkInt_RDR [ah_RDR])
- (mk_easy_App mkInt_RDR [bh_RDR])
- (HsIf (HsApp (HsApp (HsVar gt_RDR)
- (mk_easy_App mkInt_RDR [ah_RDR]))
- (mk_easy_App mkInt_RDR [bh_RDR]))
- (HsLit (HsInt 0))
+ (mkHsVarApps mkInt_RDR [ah_RDR])
+ (mkHsVarApps mkInt_RDR [bh_RDR])
+ (HsIf (mkHsApps gt_RDR [mkHsVarApps mkInt_RDR [ah_RDR],
+ mkHsVarApps mkInt_RDR [bh_RDR]])
+ (mkHsIntLit 0)
(HsVar (maxtag_RDR tycon))
tycon_loc))
from_enum
= mk_easy_FunMonoBind tycon_loc fromEnum_RDR [a_Pat] [] $
untag_Expr tycon [(a_RDR, ah_RDR)] $
- (mk_easy_App mkInt_RDR [ah_RDR])
+ (mkHsVarApps mkInt_RDR [ah_RDR])
\end{code}
%************************************************************************
= if isEnumerationTyCon tycon then
min_bound_enum `AndMonoBinds` max_bound_enum
else
- ASSERT(length data_cons == 1)
+ ASSERT(isSingleton data_cons)
min_bound_1con `AndMonoBinds` max_bound_1con
where
data_cons = tyConDataCons tycon
arity = dataConSourceArity data_con_1
min_bound_1con = mk_easy_FunMonoBind tycon_loc minBound_RDR [] [] $
- mk_easy_App data_con_1_RDR (nOfThem arity minBound_RDR)
+ mkHsVarApps data_con_1_RDR (nOfThem arity minBound_RDR)
max_bound_1con = mk_easy_FunMonoBind tycon_loc maxBound_RDR [] [] $
- mk_easy_App data_con_1_RDR (nOfThem arity maxBound_RDR)
+ mkHsVarApps data_con_1_RDR (nOfThem arity maxBound_RDR)
\end{code}
%************************************************************************
[TuplePatIn [a_Pat, b_Pat] Boxed] [] $
untag_Expr tycon [(a_RDR, ah_RDR)] $
untag_Expr tycon [(b_RDR, bh_RDR)] $
- HsApp (mk_easy_App map_RDR [tag2con_RDR tycon]) $
+ HsApp (mkHsVarApps map_RDR [tag2con_RDR tycon]) $
HsPar (enum_from_to_Expr
- (mk_easy_App mkInt_RDR [ah_RDR])
- (mk_easy_App mkInt_RDR [bh_RDR]))
+ (mkHsVarApps mkInt_RDR [ah_RDR])
+ (mkHsVarApps mkInt_RDR [bh_RDR]))
enum_index
= mk_easy_FunMonoBind tycon_loc index_RDR
[AsPatIn c_RDR (TuplePatIn [a_Pat, wildPat] Boxed),
d_Pat] [] (
- HsIf (HsPar (mk_easy_App inRange_RDR [c_RDR, d_RDR])) (
+ HsIf (HsPar (mkHsVarApps inRange_RDR [c_RDR, d_RDR])) (
untag_Expr tycon [(a_RDR, ah_RDR)] (
untag_Expr tycon [(d_RDR, dh_RDR)] (
let
- rhs = mk_easy_App mkInt_RDR [c_RDR]
+ rhs = mkHsVarApps mkInt_RDR [c_RDR]
in
HsCase
(genOpApp (HsVar dh_RDR) minusH_RDR (HsVar ah_RDR))
- [mkSimpleMatch [VarPatIn c_RDR] rhs Nothing tycon_loc]
+ [mkSimpleMatch [VarPatIn c_RDR] rhs placeHolderType tycon_loc]
tycon_loc
))
) {-else-} (
- HsApp (HsVar error_RDR) (HsLit (HsString (_PK_ ("Ix."++tycon_str++".index: out of range\n"))))
+ HsApp (HsVar error_RDR) (HsLit (HsString (mkFastString ("Ix."++tycon_str++".index: out of range\n"))))
)
tycon_loc)
cs_needed = take con_arity cs_RDRs
con_pat xs = ConPatIn data_con_RDR (map VarPatIn xs)
- con_expr = mk_easy_App data_con_RDR cs_needed
+ con_expr = mkHsVarApps data_con_RDR cs_needed
--------------------------------------------------------------
single_con_range
= mk_easy_FunMonoBind tycon_loc range_RDR
[TuplePatIn [con_pat as_needed, con_pat bs_needed] Boxed] [] $
- HsDo ListComp stmts tycon_loc
+ mkHsDo ListComp stmts tycon_loc
where
stmts = zipWith3Equal "single_con_range" mk_qual as_needed bs_needed cs_needed
++
- [ExprStmt con_expr tycon_loc]
+ [ResultStmt con_expr tycon_loc]
mk_qual a b c = BindStmt (VarPatIn c)
(HsApp (HsVar range_RDR)
= mk_easy_FunMonoBind tycon_loc index_RDR
[TuplePatIn [con_pat as_needed, con_pat bs_needed] Boxed,
con_pat cs_needed] [range_size] (
- foldl mk_index (HsLit (HsInt 0)) (zip3 as_needed bs_needed cs_needed))
+ foldl mk_index (mkHsIntLit 0) (zip3 as_needed bs_needed cs_needed))
where
mk_index multiply_by (l, u, i)
= genOpApp (
- (HsApp (HsApp (HsVar index_RDR)
- (ExplicitTuple [HsVar l, HsVar u] Boxed)) (HsVar i))
+ (mkHsApps index_RDR [ExplicitTuple [HsVar l, HsVar u] Boxed,
+ HsVar i])
) plus_RDR (
genOpApp (
(HsApp (HsVar rangeSize_RDR)
= mk_easy_FunMonoBind tycon_loc rangeSize_RDR
[TuplePatIn [a_Pat, b_Pat] Boxed] [] (
genOpApp (
- (HsApp (HsApp (HsVar index_RDR)
- (ExplicitTuple [a_Expr, b_Expr] Boxed)) b_Expr)
- ) plus_RDR (HsLit (HsInt 1)))
+ (mkHsApps index_RDR [ExplicitTuple [a_Expr, b_Expr] Boxed,
+ b_Expr])
+ ) plus_RDR (mkHsIntLit 1))
------------------
single_con_inRange
[] (
foldl1 and_Expr (zipWith3Equal "single_con_inRange" in_range as_needed bs_needed cs_needed))
where
- in_range a b c = HsApp (HsApp (HsVar inRange_RDR)
- (ExplicitTuple [HsVar a, HsVar b] Boxed))
- (HsVar c)
+ in_range a b c = mkHsApps inRange_RDR [ExplicitTuple [HsVar a, HsVar b] Boxed,
+ HsVar c]
\end{code}
%************************************************************************
%* *
%************************************************************************
+Example
+
+ infix 4 %%
+ data T = Int %% Int
+ | T1 { f1 :: Int }
+ | T2 Int
+
+
+instance Read T where
+ readPrec =
+ block
+ ( prec 4 (
+ do x <- ReadP.step Read.readPrec
+ Symbol "%%" <- Lex.lex
+ y <- ReadP.step Read.readPrec
+ return (x %% y))
+ +++
+ prec appPrec (
+ do Ident "T1" <- Lex.lex
+ Punc '{' <- Lex.lex
+ Ident "f1" <- Lex.lex
+ Punc '=' <- Lex.lex
+ x <- ReadP.reset Read.readPrec
+ Punc '}' <- Lex.lex
+ return (T1 { f1 = x }))
+ +++
+ prec appPrec (
+ do Ident "T2" <- Lex.lexP
+ x <- ReadP.step Read.readPrec
+ return (T2 x))
+ )
+
+ readListPrec = readListPrecDefault
+ readList = readListDefault
+
+
\begin{code}
-gen_Read_binds :: (Name -> Maybe Fixity) -> TyCon -> RdrNameMonoBinds
+gen_Read_binds :: FixityEnv -> TyCon -> RdrNameMonoBinds
gen_Read_binds get_fixity tycon
- = reads_prec `AndMonoBinds` read_list
+ = read_prec `AndMonoBinds` default_binds
where
- tycon_loc = getSrcLoc tycon
-----------------------------------------------------------------------
- read_list = mk_easy_FunMonoBind tycon_loc readList_RDR [] []
- (HsApp (HsVar readList___RDR) (HsPar (HsApp (HsVar readsPrec_RDR) (HsLit (HsInt 0)))))
+ default_binds
+ = mk_easy_FunMonoBind loc readList_RDR [] [] (HsVar readListDefault_RDR)
+ `AndMonoBinds`
+ mk_easy_FunMonoBind loc readListPrec_RDR [] [] (HsVar readListPrecDefault_RDR)
-----------------------------------------------------------------------
- reads_prec
- = let
- read_con_comprehensions
- = map read_con (tyConDataCons tycon)
- in
- mk_easy_FunMonoBind tycon_loc readsPrec_RDR [zz_a_Pat, b_Pat] [] (
- foldr1 append_Expr read_con_comprehensions
- )
+
+ loc = getSrcLoc tycon
+ data_cons = tyConDataCons tycon
+ (nullary_cons, non_nullary_cons) = partition isNullaryDataCon data_cons
+
+ read_prec = mk_easy_FunMonoBind loc readPrec_RDR [] []
+ (HsApp (HsVar parens_RDR) read_cons)
+
+ read_cons = foldr1 mk_alt (read_nullary_cons ++ read_non_nullary_cons)
+ read_non_nullary_cons = map read_non_nullary_con non_nullary_cons
+
+ read_nullary_cons
+ = case nullary_cons of
+ [] -> []
+ [con] -> [mkHsDo DoExpr [bindLex (ident_pat (data_con_str con)),
+ result_stmt con []] loc]
+ _ -> [HsApp (HsVar choose_RDR)
+ (ExplicitList placeHolderType (map mk_pair nullary_cons))]
+
+ mk_pair con = ExplicitTuple [HsLit (data_con_str con),
+ HsApp (HsVar returnM_RDR) (HsVar (qual_orig_name con))]
+ Boxed
+
+ read_non_nullary_con data_con
+ = mkHsApps prec_RDR [mkHsIntLit prec, mkHsDo DoExpr stmts loc]
where
- read_con data_con -- note: "b" is the string being "read"
- = HsApp (
- readParen_Expr read_paren_arg $ HsPar $
- HsLam (mk_easy_Match tycon_loc [c_Pat] [] $
- HsDo ListComp stmts tycon_loc)
- ) (HsVar b_RDR)
- where
- data_con_RDR = qual_orig_name data_con
- data_con_str = occNameUserString (getOccName data_con)
- con_arity = dataConSourceArity data_con
- con_expr = mk_easy_App data_con_RDR as_needed
- nullary_con = con_arity == 0
- labels = dataConFieldLabels data_con
- lab_fields = length labels
- dc_nm = getName data_con
- is_infix = isDataSymOcc (getOccName dc_nm)
-
- as_needed = take con_arity as_RDRs
- bs_needed
- | is_infix = take (1 + con_arity) bs_RDRs
- | lab_fields == 0 = take con_arity bs_RDRs
- | otherwise = take (4*lab_fields + 1) bs_RDRs
- -- (label, '=' and field)*n, (n-1)*',' + '{' + '}'
-
- (as1:as2:_) = as_needed
- (bs1:bs2:bs3:_) = bs_needed
-
- con_qual
- | not is_infix =
- BindStmt
- (TuplePatIn [LitPatIn (mkHsString data_con_str), d_Pat] Boxed)
- (HsApp (HsVar lex_RDR) c_Expr)
- tycon_loc
- | otherwise =
- BindStmt
- (TuplePatIn [LitPatIn (mkHsString data_con_str), VarPatIn bs2] Boxed)
- (HsApp (HsVar lex_RDR) (HsVar bs1))
- tycon_loc
-
-
- str_qual str res draw_from =
- BindStmt
- (TuplePatIn [LitPatIn (mkHsString str), VarPatIn res] Boxed)
- (HsApp (HsVar lex_RDR) draw_from)
- tycon_loc
-
- str_qual_paren str res draw_from =
- BindStmt
- (TuplePatIn [LitPatIn (mkHsString str), VarPatIn res] Boxed)
- (HsApp (readParen_Expr true_Expr (HsVar lex_RDR)) draw_from)
- tycon_loc
-
- read_label f = [rd_lab, str_qual "="]
- -- There might be spaces between the label and '='
- where
- rd_lab
- | is_op = str_qual_paren nm
- | otherwise = str_qual nm
-
- occ_nm = getOccName (fieldLabelName f)
- is_op = isSymOcc occ_nm
- nm = occNameUserString occ_nm
-
- field_quals
- | is_infix =
- snd (mapAccumL mk_qual_infix
- c_Expr
- [ (mk_read_qual lp as1, bs1, bs2)
- , (mk_read_qual rp as2, bs3, bs3)
- ])
- | lab_fields == 0 = -- common case.
- snd (mapAccumL mk_qual
- d_Expr
- (zipWithEqual "as_needed"
- (\ con_field draw_from -> (mk_read_qual 10 con_field,
- draw_from))
- as_needed bs_needed))
- | otherwise =
- snd $
- mapAccumL mk_qual d_Expr
- (zipEqual "bs_needed"
- ((str_qual "{":
- concat (
- intersperse [str_qual ","] $
- zipWithEqual
- "field_quals"
- (\ as b -> as ++ [b])
- -- The labels
- (map read_label labels)
- -- The fields
- (map (mk_read_qual 10) as_needed))) ++ [str_qual "}"])
- bs_needed)
-
- mk_qual_infix draw_from (f, str_left, str_left2) =
- (HsVar str_left2, -- what to draw from down the line...
- f str_left draw_from)
-
- mk_qual draw_from (f, str_left) =
- (HsVar str_left, -- what to draw from down the line...
- f str_left draw_from)
-
- mk_read_qual p con_field res draw_from =
- BindStmt
- (TuplePatIn [VarPatIn con_field, VarPatIn res] Boxed)
- (HsApp (HsApp (HsVar readsPrec_RDR) (HsLit (HsInt p))) draw_from)
- tycon_loc
-
- result_expr = ExplicitTuple [con_expr, if null bs_needed
- then d_Expr
- else HsVar (last bs_needed)] Boxed
-
- [lp,rp] = getLRPrecs is_infix get_fixity dc_nm
-
- quals
- | is_infix = let (h:t) = field_quals in (h:con_qual:t)
- | otherwise = con_qual:field_quals
-
- stmts = quals ++ [ExprStmt result_expr tycon_loc]
-
- {-
- c.f. Figure 18 in Haskell 1.1 report.
- -}
- paren_prec_limit
- | not is_infix = defaultPrecedence
- | otherwise = getPrecedence get_fixity dc_nm
-
- read_paren_arg -- parens depend on precedence...
- | nullary_con = false_Expr -- it's optional.
- | otherwise = HsPar (genOpApp zz_a_Expr gt_RDR (HsLit (HsInt paren_prec_limit)))
+ stmts | is_infix = infix_stmts
+ | length labels > 0 = lbl_stmts
+ | otherwise = prefix_stmts
+
+ prefix_stmts -- T a b c
+ = [bindLex (ident_pat (data_con_str data_con))]
+ ++ map read_arg as_needed
+ ++ [result_stmt data_con as_needed]
+
+ infix_stmts -- a %% b
+ = [read_arg a1,
+ bindLex (symbol_pat (data_con_str data_con)),
+ read_arg a2,
+ result_stmt data_con [a1,a2]]
+
+ lbl_stmts -- T { f1 = a, f2 = b }
+ = [bindLex (ident_pat (data_con_str data_con)),
+ read_punc "{"]
+ ++ concat (intersperse [read_punc ","] field_stmts)
+ ++ [read_punc "}", result_stmt data_con as_needed]
+
+ field_stmts = zipWithEqual "lbl_stmts" read_field labels as_needed
+
+ con_arity = dataConSourceArity data_con
+ nullary_con = con_arity == 0
+ labels = dataConFieldLabels data_con
+ lab_fields = length labels
+ dc_nm = getName data_con
+ is_infix = isDataSymOcc (getOccName dc_nm)
+ as_needed = take con_arity as_RDRs
+ (a1:a2:_) = as_needed
+ prec = getPrec is_infix get_fixity dc_nm
+
+ ------------------------------------------------------------------------
+ -- Helpers
+ ------------------------------------------------------------------------
+ mk_alt e1 e2 = genOpApp e1 alt_RDR e2
+ bindLex pat = BindStmt pat (HsVar lexP_RDR) loc
+ result_stmt c as = ResultStmt (HsApp (HsVar returnM_RDR) (con_app c as)) loc
+ con_app c as = mkHsVarApps (qual_orig_name c) as
+
+ punc_pat s = ConPatIn punc_RDR [LitPatIn (mkHsString s)] -- Punc 'c'
+ ident_pat s = ConPatIn ident_RDR [LitPatIn s] -- Ident "foo"
+ symbol_pat s = ConPatIn symbol_RDR [LitPatIn s] -- Symbol ">>"
+
+ data_con_str con = mkHsString (occNameUserString (getOccName con))
+
+ read_punc c = bindLex (punc_pat c)
+ read_arg a = BindStmt (VarPatIn a) (mkHsVarApps step_RDR [readPrec_RDR]) loc
+
+ read_field lbl a = read_lbl lbl ++
+ [read_punc "=",
+ BindStmt (VarPatIn a) (mkHsVarApps reset_RDR [readPrec_RDR]) loc]
+
+ -- When reading field labels we might encounter
+ -- a = 3
+ -- or (#) = 4
+ -- Note the parens!
+ read_lbl lbl | isAlpha (head lbl_str)
+ = [bindLex (ident_pat lbl_lit)]
+ | otherwise
+ = [read_punc "(",
+ bindLex (symbol_pat lbl_lit),
+ read_punc ")"]
+ where
+ lbl_str = occNameUserString (getOccName (fieldLabelName lbl))
+ lbl_lit = mkHsString lbl_str
\end{code}
+
%************************************************************************
%* *
\subsubsection{Generating @Show@ instance declarations}
%************************************************************************
\begin{code}
-gen_Show_binds :: (Name -> Maybe Fixity) -> TyCon -> RdrNameMonoBinds
+gen_Show_binds :: FixityEnv -> TyCon -> RdrNameMonoBinds
gen_Show_binds get_fixity tycon
= shows_prec `AndMonoBinds` show_list
tycon_loc = getSrcLoc tycon
-----------------------------------------------------------------------
show_list = mk_easy_FunMonoBind tycon_loc showList_RDR [] []
- (HsApp (HsVar showList___RDR) (HsPar (HsApp (HsVar showsPrec_RDR) (HsLit (HsInt 0)))))
+ (HsApp (HsVar showList___RDR) (HsPar (HsApp (HsVar showsPrec_RDR) (mkHsIntLit 0))))
-----------------------------------------------------------------------
shows_prec = mk_FunMonoBind tycon_loc showsPrec_RDR (map pats_etc (tyConDataCons tycon))
where
pats_etc data_con
| nullary_con = -- skip the showParen junk...
ASSERT(null bs_needed)
- ([wildPat, con_pat], show_con)
+ ([wildPat, con_pat], mk_showString_app con_str)
| otherwise =
([a_Pat, con_pat],
- showParen_Expr (HsPar (genOpApp a_Expr ge_RDR (HsLit (HsInt paren_prec_limit))))
+ showParen_Expr (HsPar (genOpApp a_Expr ge_RDR (HsLit (HsInt con_prec))))
(HsPar (nested_compose_Expr show_thingies)))
where
- data_con_RDR = qual_orig_name data_con
- con_arity = dataConSourceArity data_con
- bs_needed = take con_arity bs_RDRs
- con_pat = ConPatIn data_con_RDR (map VarPatIn bs_needed)
- nullary_con = con_arity == 0
- labels = dataConFieldLabels data_con
- lab_fields = length labels
+ data_con_RDR = qual_orig_name data_con
+ con_arity = dataConSourceArity data_con
+ bs_needed = take con_arity bs_RDRs
+ con_pat = ConPatIn data_con_RDR (map VarPatIn bs_needed)
+ nullary_con = con_arity == 0
+ labels = dataConFieldLabels data_con
+ lab_fields = length labels
+ record_syntax = lab_fields > 0
dc_nm = getName data_con
dc_occ_nm = getOccName data_con
- dc_occ_nm_str = occNameUserString dc_occ_nm
-
- is_infix = isDataSymOcc dc_occ_nm
-
+ con_str = occNameUserString dc_occ_nm
- show_con
- | is_infix = mk_showString_app (' ':dc_occ_nm_str)
- | otherwise = mk_showString_app (dc_occ_nm_str ++ space_ocurly_maybe)
- where
- space_ocurly_maybe
- | nullary_con = ""
- | lab_fields == 0 = " "
- | otherwise = "{"
-
-
- show_all con fs@(x:xs)
- | is_infix = x:con:xs
- | otherwise =
- let
- ccurly_maybe
- | lab_fields > 0 = [mk_showString_app "}"]
- | otherwise = []
- in
- con:fs ++ ccurly_maybe
-
- show_thingies = show_all show_con real_show_thingies_with_labs
+ show_thingies
+ | is_infix = [show_arg1, mk_showString_app (" " ++ con_str ++ " "), show_arg2]
+ | record_syntax = mk_showString_app (con_str ++ " {") :
+ show_record_args ++ [mk_showString_app "}"]
+ | otherwise = mk_showString_app (con_str ++ " ") : show_prefix_args
show_label l = mk_showString_app (the_name ++ "=")
where
occ_nm = getOccName (fieldLabelName l)
- -- legal, but rare.
- is_op = isSymOcc occ_nm
+ nm = occNameUserString occ_nm
+
+ is_op = isSymOcc occ_nm -- Legal, but rare.
the_name
| is_op = '(':nm ++ ")"
| otherwise = nm
- nm = occNameUserString occ_nm
-
-
- mk_showString_app str = HsApp (HsVar showString_RDR)
- (HsLit (mkHsString str))
-
- prec_cons = getLRPrecs is_infix get_fixity dc_nm
-
- real_show_thingies
- | is_infix =
- [ HsApp (HsApp (HsVar showsPrec_RDR) (HsLit (HsInt p))) (HsVar b)
- | (p,b) <- zip prec_cons bs_needed ]
- | otherwise =
- [ HsApp (HsApp (HsVar showsPrec_RDR) (HsLit (HsInt 10))) (HsVar b)
- | b <- bs_needed ]
-
- real_show_thingies_with_labs
- | lab_fields == 0 = intersperse (HsVar showSpace_RDR) real_show_thingies
- | otherwise = --Assumption: no of fields == no of labelled fields
- -- (and in same order)
- concat $
- intersperse ([mk_showString_app ","]) $ -- Using SLIT()s containing ,s spells trouble.
- zipWithEqual "gen_Show_binds"
- (\ a b -> [a,b])
- (map show_label labels)
- real_show_thingies
+ show_args = [ mkHsApps showsPrec_RDR [HsLit (HsInt arg_prec), HsVar b]
+ | b <- bs_needed ]
+ (show_arg1:show_arg2:_) = show_args
+ show_prefix_args = intersperse (HsVar showSpace_RDR) show_args
+
+
+ -- Assumption for record syntax: no of fields == no of labelled fields
+ -- (and in same order)
+ show_record_args = concat $
+ intersperse [mk_showString_app ", "] $
+ [ [show_label lbl, arg]
+ | (lbl,arg) <- zipEqual "gen_Show_binds"
+ labels show_args ]
- {-
- c.f. Figure 16 and 17 in Haskell 1.1 report
- -}
- paren_prec_limit
- | not is_infix = defaultPrecedence + 1
- | otherwise = getPrecedence get_fixity dc_nm + 1
+ -- Fixity stuff
+ is_infix = isDataSymOcc dc_occ_nm
+ con_prec = 1 + getPrec is_infix get_fixity dc_nm
+ arg_prec | record_syntax = 0 -- Record fields don't need parens
+ | otherwise = con_prec
+mk_showString_app str = HsApp (HsVar showString_RDR) (HsLit (mkHsString str))
\end{code}
\begin{code}
-getLRPrecs :: Bool -> (Name -> Maybe Fixity) -> Name -> [Integer]
-getLRPrecs is_infix get_fixity nm = [lp, rp]
- where
- {-
- Figuring out the fixities of the arguments to a constructor,
- cf. Figures 16-18 in Haskell 1.1 report.
- -}
- (con_left_assoc, con_right_assoc) = isLRAssoc get_fixity nm
- paren_con_prec = getPrecedence get_fixity nm
-
- lp
- | not is_infix = defaultPrecedence + 1
- | con_left_assoc = paren_con_prec
- | otherwise = paren_con_prec + 1
-
- rp
- | not is_infix = defaultPrecedence + 1
- | con_right_assoc = paren_con_prec
- | otherwise = paren_con_prec + 1
+getPrec :: Bool -> FixityEnv -> Name -> Integer
+getPrec is_infix get_fixity nm
+ | not is_infix = appPrecedence
+ | otherwise = getPrecedence get_fixity nm
-defaultPrecedence :: Integer
-defaultPrecedence = fromInt maxPrecedence
+appPrecedence :: Integer
+appPrecedence = fromIntegral maxPrecedence
-getPrecedence :: (Name -> Maybe Fixity) -> Name -> Integer
+getPrecedence :: FixityEnv -> Name -> Integer
getPrecedence get_fixity nm
- = case get_fixity nm of
- Just (Fixity x _) -> fromInt x
- other -> defaultPrecedence
+ = case lookupFixity get_fixity nm of
+ Fixity x _ -> fromIntegral x
-isLRAssoc :: (Name -> Maybe Fixity) -> Name -> (Bool, Bool)
+isLRAssoc :: FixityEnv -> Name -> (Bool, Bool)
isLRAssoc get_fixity nm =
- case get_fixity nm `orElse` defaultFixity of
+ case lookupFixity get_fixity nm of
Fixity _ InfixN -> (False, False)
Fixity _ InfixR -> (False, True)
Fixity _ InfixL -> (True, False)
-
-isInfixOccName :: String -> Bool
-isInfixOccName str =
- case str of
- (':':_) -> True
- _ -> False
\end{code}
loc
mk_match loc pats expr binds
- = Match [] (map paren pats) Nothing
- (GRHSs (unguardedRHS expr loc) binds Nothing)
+ = Match (map paren pats) Nothing
+ (GRHSs (unguardedRHS expr loc) binds placeHolderType)
where
paren p@(VarPatIn _) = p
paren other_p = ParPatIn other_p
\end{code}
\begin{code}
-mk_easy_App f xs = foldl HsApp (HsVar f) (map HsVar xs)
+mkHsApps f xs = foldl HsApp (HsVar f) xs
+mkHsVarApps f xs = foldl HsApp (HsVar f) (map HsVar xs)
+
+mkHsIntLit n = HsLit (HsInt n)
+mkHsString s = HsString (mkFastString s)
+mkHsChar c = HsChar (ord c)
\end{code}
ToDo: Better SrcLocs.
\begin{code}
-compare_Case ::
- RdrNameHsExpr -> RdrNameHsExpr -> RdrNameHsExpr
- -> RdrNameHsExpr -> RdrNameHsExpr
- -> RdrNameHsExpr
compare_gen_Case ::
RdrName
-> RdrNameHsExpr -> RdrNameHsExpr -> RdrNameHsExpr
-> RdrNameHsExpr -> RdrNameHsExpr
-> RdrNameHsExpr
-compare_Case = compare_gen_Case compare_RDR
cmp_eq_Expr a b = HsApp (HsApp (HsVar cmp_eq_RDR) a) b
-- Was: compare_gen_Case cmp_eq_RDR
compare_gen_Case fun lt eq gt a b
= HsCase (HsPar (HsApp (HsApp (HsVar fun) a) b)) {-of-}
- [mkSimpleMatch [ConPatIn ltTag_RDR []] lt Nothing generatedSrcLoc,
- mkSimpleMatch [ConPatIn eqTag_RDR []] eq Nothing generatedSrcLoc,
- mkSimpleMatch [ConPatIn gtTag_RDR []] gt Nothing generatedSrcLoc]
+ [mkSimpleMatch [ConPatIn ltTag_RDR []] lt placeHolderType generatedSrcLoc,
+ mkSimpleMatch [ConPatIn eqTag_RDR []] eq placeHolderType generatedSrcLoc,
+ mkSimpleMatch [ConPatIn gtTag_RDR []] gt placeHolderType generatedSrcLoc]
generatedSrcLoc
careful_compare_Case ty lt eq gt a b
- = if not (isUnLiftedType ty) then
+ | not (isUnLiftedType ty) =
compare_gen_Case compare_RDR lt eq gt a b
-
- else -- we have to do something special for primitive things...
+ | otherwise =
+ -- we have to do something special for primitive things...
HsIf (genOpApp a relevant_eq_op b)
eq
(HsIf (genOpApp a relevant_lt_op b) lt gt generatedSrcLoc)
= if null res then panic "assoc_ty"
else head res
where
- res = [id | (ty',id) <- tyids, ty == ty']
+ res = [id | (ty',id) <- tyids, ty `tcEqType` ty']
eq_op_tbl =
[(charPrimTy, eqH_Char_RDR)
-----------------------------------------------------------------------
eq_Expr :: Type -> RdrNameHsExpr -> RdrNameHsExpr -> RdrNameHsExpr
-eq_Expr ty a b
- = if not (isUnLiftedType ty) then
- genOpApp a eq_RDR b
- else -- we have to do something special for primitive things...
- genOpApp a relevant_eq_op b
- where
- relevant_eq_op = assoc_ty_id eq_op_tbl ty
+eq_Expr ty a b = genOpApp a eq_op b
+ where
+ eq_op
+ | not (isUnLiftedType ty) = eq_RDR
+ | otherwise =
+ -- we have to do something special for primitive things...
+ assoc_ty_id eq_op_tbl ty
+
\end{code}
\begin{code}
untag_Expr tycon [] expr = expr
untag_Expr tycon ((untag_this, put_tag_here) : more) expr
= HsCase (HsPar (HsApp (con2tag_Expr tycon) (HsVar untag_this))) {-of-}
- [mkSimpleMatch [VarPatIn put_tag_here] (untag_Expr tycon more expr) Nothing generatedSrcLoc]
+ [mkSimpleMatch [VarPatIn put_tag_here] (untag_Expr tycon more expr) placeHolderType generatedSrcLoc]
generatedSrcLoc
cmp_tags_Expr :: RdrName -- Comparison op
enum_from_to_Expr f t2 = HsApp (HsApp (HsVar enumFromTo_RDR) f) t2
enum_from_then_to_Expr f t t2 = HsApp (HsApp (HsApp (HsVar enumFromThenTo_RDR) f) t) t2
-showParen_Expr, readParen_Expr
+showParen_Expr
:: RdrNameHsExpr -> RdrNameHsExpr
-> RdrNameHsExpr
showParen_Expr e1 e2 = HsApp (HsApp (HsVar showParen_RDR) e1) e2
-readParen_Expr e1 e2 = HsApp (HsApp (HsVar readParen_RDR) e1) e2
nested_compose_Expr :: [RdrNameHsExpr] -> RdrNameHsExpr
-- 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 = HsApp (HsVar error_RDR) (HsLit (HsString (_PK_ "Urk! in TcGenDeriv")))
+impossible_Expr = HsApp (HsVar error_RDR) (HsLit (HsString (mkFastString "Urk! in TcGenDeriv")))
-- illegal_Expr is used when signalling error conditions in the RHS of a derived
-- method. It is currently only used by Enum.{succ,pred}
illegal_Expr meth tp msg =
- HsApp (HsVar error_RDR) (HsLit (HsString (_PK_ (meth ++ '{':tp ++ "}: " ++ msg))))
+ HsApp (HsVar error_RDR) (HsLit (HsString (mkFastString (meth ++ '{':tp ++ "}: " ++ msg))))
-- illegal_toEnum_tag is an extended version of illegal_Expr, which also allows you
-- to include the value of a_RDR in the error string.
illegal_toEnum_tag tp maxtag =
HsApp (HsVar error_RDR)
(HsApp (HsApp (HsVar append_RDR)
- (HsLit (HsString (_PK_ ("toEnum{" ++ tp ++ "}: tag (")))))
+ (HsLit (HsString (mkFastString ("toEnum{" ++ tp ++ "}: tag (")))))
(HsApp (HsApp (HsApp
(HsVar showsPrec_RDR)
- (HsLit (HsInt 0)))
+ (mkHsIntLit 0))
(HsVar a_RDR))
(HsApp (HsApp
(HsVar append_RDR)
- (HsLit (HsString (_PK_ ") is outside of enumeration's range (0,"))))
+ (HsLit (HsString (mkFastString ") is outside of enumeration's range (0,"))))
(HsApp (HsApp (HsApp
(HsVar showsPrec_RDR)
- (HsLit (HsInt 0)))
+ (mkHsIntLit 0))
(HsVar maxtag))
- (HsLit (HsString (_PK_ ")")))))))
+ (HsLit (HsString (mkFastString ")")))))))
parenify e@(HsVar _) = e
parenify e = HsPar e
qual_orig_name n = nameRdrName (getName n)
varUnqual n = mkUnqual varName n
-zz_a_RDR = varUnqual SLIT("_a")
-a_RDR = varUnqual SLIT("a")
-b_RDR = varUnqual SLIT("b")
-c_RDR = varUnqual SLIT("c")
-d_RDR = varUnqual SLIT("d")
-ah_RDR = varUnqual SLIT("a#")
-bh_RDR = varUnqual SLIT("b#")
-ch_RDR = varUnqual SLIT("c#")
-dh_RDR = varUnqual SLIT("d#")
-cmp_eq_RDR = varUnqual SLIT("cmp_eq")
-rangeSize_RDR = varUnqual SLIT("rangeSize")
-
-as_RDRs = [ varUnqual (_PK_ ("a"++show i)) | i <- [(1::Int) .. ] ]
-bs_RDRs = [ varUnqual (_PK_ ("b"++show i)) | i <- [(1::Int) .. ] ]
-cs_RDRs = [ varUnqual (_PK_ ("c"++show i)) | i <- [(1::Int) .. ] ]
-
-mkHsString s = HsString (_PK_ s)
+zz_a_RDR = varUnqual FSLIT("_a")
+a_RDR = varUnqual FSLIT("a")
+b_RDR = varUnqual FSLIT("b")
+c_RDR = varUnqual FSLIT("c")
+d_RDR = varUnqual FSLIT("d")
+ah_RDR = varUnqual FSLIT("a#")
+bh_RDR = varUnqual FSLIT("b#")
+ch_RDR = varUnqual FSLIT("c#")
+dh_RDR = varUnqual FSLIT("d#")
+cmp_eq_RDR = varUnqual FSLIT("cmp_eq")
+rangeSize_RDR = varUnqual FSLIT("rangeSize")
+
+as_RDRs = [ varUnqual (mkFastString ("a"++show i)) | i <- [(1::Int) .. ] ]
+bs_RDRs = [ varUnqual (mkFastString ("b"++show i)) | i <- [(1::Int) .. ] ]
+cs_RDRs = [ varUnqual (mkFastString ("c"++show i)) | i <- [(1::Int) .. ] ]
zz_a_Expr = HsVar zz_a_RDR
a_Expr = HsVar a_RDR
con2tag_RDR, tag2con_RDR, maxtag_RDR :: TyCon -> RdrName
-con2tag_RDR tycon = varUnqual (_PK_ ("con2tag_" ++ occNameString (getOccName tycon) ++ "#"))
-tag2con_RDR tycon = varUnqual (_PK_ ("tag2con_" ++ occNameString (getOccName tycon) ++ "#"))
-maxtag_RDR tycon = varUnqual (_PK_ ("maxtag_" ++ occNameString (getOccName tycon) ++ "#"))
+con2tag_RDR tycon = varUnqual (mkFastString ("con2tag_" ++ occNameString (getOccName tycon) ++ "#"))
+tag2con_RDR tycon = varUnqual (mkFastString ("tag2con_" ++ occNameString (getOccName tycon) ++ "#"))
+maxtag_RDR tycon = varUnqual (mkFastString ("maxtag_" ++ occNameString (getOccName tycon) ++ "#"))
\end{code}