mirrored from https://gitlab.haskell.org/ghc/ghc.git
-
Notifications
You must be signed in to change notification settings - Fork 705
/
Parser.y.pp
2167 lines (1773 loc) · 95.4 KB
/
Parser.y.pp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
-- -*-haskell-*-
-- ---------------------------------------------------------------------------
-- (c) The University of Glasgow 1997-2003
---
-- The GHC grammar.
--
-- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
-- ---------------------------------------------------------------------------
{
{-# LANGUAGE BangPatterns #-} -- required for versions of Happy before 1.18.6
{-# OPTIONS -Wwarn -w #-}
-- 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
-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
-- for details
{-# OPTIONS_GHC -O0 -fno-ignore-interface-pragmas #-}
{-
Careful optimisation of the parser: we don't want to throw everything
at it, because that takes too long and doesn't buy much, but we do want
to inline certain key external functions, so we instruct GHC not to
throw away inlinings as it would normally do in -O0 mode.
-}
module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
parseHeader ) where
import HsSyn
import RdrHsSyn
import HscTypes ( IsBootInterface, WarningTxt(..) )
import Lexer
import RdrName
import TcEvidence ( emptyTcEvBinds )
import TysPrim ( liftedTypeKindTyConName, eqPrimTyCon )
import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
unboxedUnitTyCon, unboxedUnitDataCon,
listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR, eqTyCon_RDR )
import Type ( funTyCon )
import ForeignCall
import OccName ( varName, dataName, tcClsName, tvName )
import DataCon ( DataCon, dataConName )
import SrcLoc
import Module
import StaticFlags ( opt_SccProfilingOn, opt_Hpc )
import Kind ( Kind, liftedTypeKind, unliftedTypeKind, mkArrowKind )
import Class ( FunDep )
import BasicTypes
import DynFlags
import OrdList
import HaddockUtils
import FastString
import Maybes ( orElse )
import Outputable
import Control.Monad ( unless, liftM )
import GHC.Exts
import Data.Char
import Control.Monad ( mplus )
}
{-
-----------------------------------------------------------------------------
24 Februar 2006
Conflicts: 33 shift/reduce
1 reduce/reduce
The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
would think the two should never occur in the same context.
-=chak
-----------------------------------------------------------------------------
31 December 2006
Conflicts: 34 shift/reduce
1 reduce/reduce
The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
would think the two should never occur in the same context.
-=chak
-----------------------------------------------------------------------------
6 December 2006
Conflicts: 32 shift/reduce
1 reduce/reduce
The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
would think the two should never occur in the same context.
-=chak
-----------------------------------------------------------------------------
26 July 2006
Conflicts: 37 shift/reduce
1 reduce/reduce
The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
would think the two should never occur in the same context.
-=chak
-----------------------------------------------------------------------------
Conflicts: 38 shift/reduce (1.25)
10 for abiguity in 'if x then y else z + 1' [State 178]
(shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
1 for ambiguity in 'if x then y else z :: T' [State 178]
(shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
4 for ambiguity in 'if x then y else z -< e' [State 178]
(shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
There are four such operators: -<, >-, -<<, >>-
2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
Which of these two is intended?
case v of
(x::T) -> T -- Rhs is T
or
case v of
(x::T -> T) -> .. -- Rhs is ...
10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
(e::a) `b` c, or
(e :: (a `b` c))
As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
Same duplication between states 11 and 253 as the previous case
1 for ambiguity in 'let ?x ...' [State 329]
the parser can't tell whether the ?x is the lhs of a normal binding or
an implicit binding. Fortunately resolving as shift gives it the only
sensible meaning, namely the lhs of an implicit binding.
1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
we don't know whether the '[' starts the activation or not: it
might be the start of the declaration with the activation being
empty. --SDM 1/4/2002
1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
since 'forall' is a valid variable name, we don't know whether
to treat a forall on the input as the beginning of a quantifier
or the beginning of the rule itself. Resolving to shift means
it's always treated as a quantifier, hence the above is disallowed.
This saves explicitly defining a grammar for the rule lhs that
doesn't include 'forall'.
1 for ambiguity when the source file starts with "-- | doc". We need another
token of lookahead to determine if a top declaration or the 'module' keyword
follows. Shift parses as if the 'module' keyword follows.
-- ---------------------------------------------------------------------------
-- Adding location info
This is done in a stylised way using the three macros below, L0, L1
and LL. Each of these macros can be thought of as having type
L0, L1, LL :: a -> Located a
They each add a SrcSpan to their argument.
L0 adds 'noSrcSpan', used for empty productions
-- This doesn't seem to work anymore -=chak
L1 for a production with a single token on the lhs. Grabs the SrcSpan
from that token.
LL for a production with >1 token on the lhs. Makes up a SrcSpan from
the first and last tokens.
These suffice for the majority of cases. However, we must be
especially careful with empty productions: LL won't work if the first
or last token on the lhs can represent an empty span. In these cases,
we have to calculate the span using more of the tokens from the lhs, eg.
| 'newtype' tycl_hdr '=' newconstr deriving
{ L (comb3 $1 $4 $5)
(mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
We provide comb3 and comb4 functions which are useful in such cases.
Be careful: there's no checking that you actually got this right, the
only symptom will be that the SrcSpans of your syntax will be
incorrect.
/*
* We must expand these macros *before* running Happy, which is why this file is
* Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
*/
#define L0 L noSrcSpan
#define L1 sL (getLoc $1)
#define LL sL (comb2 $1 $>)
-- -----------------------------------------------------------------------------
-}
%token
'_' { L _ ITunderscore } -- Haskell keywords
'as' { L _ ITas }
'case' { L _ ITcase }
'class' { L _ ITclass }
'data' { L _ ITdata }
'default' { L _ ITdefault }
'deriving' { L _ ITderiving }
'do' { L _ ITdo }
'else' { L _ ITelse }
'hiding' { L _ IThiding }
'if' { L _ ITif }
'import' { L _ ITimport }
'in' { L _ ITin }
'infix' { L _ ITinfix }
'infixl' { L _ ITinfixl }
'infixr' { L _ ITinfixr }
'instance' { L _ ITinstance }
'let' { L _ ITlet }
'module' { L _ ITmodule }
'newtype' { L _ ITnewtype }
'of' { L _ ITof }
'qualified' { L _ ITqualified }
'then' { L _ ITthen }
'type' { L _ ITtype }
'where' { L _ ITwhere }
'_scc_' { L _ ITscc } -- ToDo: remove
'forall' { L _ ITforall } -- GHC extension keywords
'foreign' { L _ ITforeign }
'export' { L _ ITexport }
'label' { L _ ITlabel }
'dynamic' { L _ ITdynamic }
'safe' { L _ ITsafe }
'interruptible' { L _ ITinterruptible }
'unsafe' { L _ ITunsafe }
'mdo' { L _ ITmdo }
'family' { L _ ITfamily }
'stdcall' { L _ ITstdcallconv }
'ccall' { L _ ITccallconv }
'capi' { L _ ITcapiconv }
'prim' { L _ ITprimcallconv }
'proc' { L _ ITproc } -- for arrow notation extension
'rec' { L _ ITrec } -- for arrow notation extension
'group' { L _ ITgroup } -- for list transform extension
'by' { L _ ITby } -- for list transform extension
'using' { L _ ITusing } -- for list transform extension
'{-# INLINE' { L _ (ITinline_prag _ _) }
'{-# SPECIALISE' { L _ ITspec_prag }
'{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
'{-# SOURCE' { L _ ITsource_prag }
'{-# RULES' { L _ ITrules_prag }
'{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
'{-# SCC' { L _ ITscc_prag }
'{-# GENERATED' { L _ ITgenerated_prag }
'{-# DEPRECATED' { L _ ITdeprecated_prag }
'{-# WARNING' { L _ ITwarning_prag }
'{-# UNPACK' { L _ ITunpack_prag }
'{-# NOUNPACK' { L _ ITnounpack_prag }
'{-# ANN' { L _ ITann_prag }
'{-# VECTORISE' { L _ ITvect_prag }
'{-# VECTORISE_SCALAR' { L _ ITvect_scalar_prag }
'{-# NOVECTORISE' { L _ ITnovect_prag }
'{-# CTYPE' { L _ ITctype }
'#-}' { L _ ITclose_prag }
'..' { L _ ITdotdot } -- reserved symbols
':' { L _ ITcolon }
'::' { L _ ITdcolon }
'=' { L _ ITequal }
'\\' { L _ ITlam }
'lcase' { L _ ITlcase }
'|' { L _ ITvbar }
'<-' { L _ ITlarrow }
'->' { L _ ITrarrow }
'@' { L _ ITat }
'~' { L _ ITtilde }
'~#' { L _ ITtildehsh }
'=>' { L _ ITdarrow }
'-' { L _ ITminus }
'!' { L _ ITbang }
'*' { L _ ITstar }
'-<' { L _ ITlarrowtail } -- for arrow notation
'>-' { L _ ITrarrowtail } -- for arrow notation
'-<<' { L _ ITLarrowtail } -- for arrow notation
'>>-' { L _ ITRarrowtail } -- for arrow notation
'.' { L _ ITdot }
'{' { L _ ITocurly } -- special symbols
'}' { L _ ITccurly }
vocurly { L _ ITvocurly } -- virtual open curly (from layout)
vccurly { L _ ITvccurly } -- virtual close curly (from layout)
'[' { L _ ITobrack }
']' { L _ ITcbrack }
'[:' { L _ ITopabrack }
':]' { L _ ITcpabrack }
'(' { L _ IToparen }
')' { L _ ITcparen }
'(#' { L _ IToubxparen }
'#)' { L _ ITcubxparen }
'(|' { L _ IToparenbar }
'|)' { L _ ITcparenbar }
';' { L _ ITsemi }
',' { L _ ITcomma }
'`' { L _ ITbackquote }
SIMPLEQUOTE { L _ ITsimpleQuote } -- 'x
VARID { L _ (ITvarid _) } -- identifiers
CONID { L _ (ITconid _) }
VARSYM { L _ (ITvarsym _) }
CONSYM { L _ (ITconsym _) }
QVARID { L _ (ITqvarid _) }
QCONID { L _ (ITqconid _) }
QVARSYM { L _ (ITqvarsym _) }
QCONSYM { L _ (ITqconsym _) }
PREFIXQVARSYM { L _ (ITprefixqvarsym _) }
PREFIXQCONSYM { L _ (ITprefixqconsym _) }
IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
CHAR { L _ (ITchar _) }
STRING { L _ (ITstring _) }
INTEGER { L _ (ITinteger _) }
RATIONAL { L _ (ITrational _) }
PRIMCHAR { L _ (ITprimchar _) }
PRIMSTRING { L _ (ITprimstring _) }
PRIMINTEGER { L _ (ITprimint _) }
PRIMWORD { L _ (ITprimword _) }
PRIMFLOAT { L _ (ITprimfloat _) }
PRIMDOUBLE { L _ (ITprimdouble _) }
DOCNEXT { L _ (ITdocCommentNext _) }
DOCPREV { L _ (ITdocCommentPrev _) }
DOCNAMED { L _ (ITdocCommentNamed _) }
DOCSECTION { L _ (ITdocSection _ _) }
-- Template Haskell
'[|' { L _ ITopenExpQuote }
'[p|' { L _ ITopenPatQuote }
'[t|' { L _ ITopenTypQuote }
'[d|' { L _ ITopenDecQuote }
'|]' { L _ ITcloseQuote }
'[||' { L _ ITopenTExpQuote }
'||]' { L _ ITcloseTExpQuote }
TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
'$(' { L _ ITparenEscape } -- $( exp )
TH_ID_TY_SPLICE { L _ (ITidTyEscape _) } -- $$x
'$$(' { L _ ITparenTyEscape } -- $$( exp )
TH_TY_QUOTE { L _ ITtyQuote } -- ''T
TH_QUASIQUOTE { L _ (ITquasiQuote _) }
TH_QQUASIQUOTE { L _ (ITqQuasiQuote _) }
%monad { P } { >>= } { return }
%lexer { lexer } { L _ ITeof }
%name parseModule module
%name parseStmt maybe_stmt
%name parseIdentifier identifier
%name parseType ctype
%partial parseHeader header
%tokentype { (Located Token) }
%%
-----------------------------------------------------------------------------
-- Identifiers; one of the entry points
identifier :: { Located RdrName }
: qvar { $1 }
| qcon { $1 }
| qvarop { $1 }
| qconop { $1 }
| '(' '->' ')' { LL $ getRdrName funTyCon }
-----------------------------------------------------------------------------
-- Module Header
-- The place for module deprecation is really too restrictive, but if it
-- was allowed at its natural place just before 'module', we get an ugly
-- s/r conflict with the second alternative. Another solution would be the
-- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
-- either, and DEPRECATED is only expected to be used by people who really
-- know what they are doing. :-)
module :: { Located (HsModule RdrName) }
: maybedocheader 'module' modid maybemodwarning maybeexports 'where' body
{% fileSrcSpan >>= \ loc ->
return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4 $1
) )}
| body2
{% fileSrcSpan >>= \ loc ->
return (L loc (HsModule Nothing Nothing
(fst $1) (snd $1) Nothing Nothing
)) }
maybedocheader :: { Maybe LHsDocString }
: moduleheader { $1 }
| {- empty -} { Nothing }
missing_module_keyword :: { () }
: {- empty -} {% pushCurrentContext }
maybemodwarning :: { Maybe WarningTxt }
: '{-# DEPRECATED' strings '#-}' { Just (DeprecatedTxt $ unLoc $2) }
| '{-# WARNING' strings '#-}' { Just (WarningTxt $ unLoc $2) }
| {- empty -} { Nothing }
body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
: '{' top '}' { $2 }
| vocurly top close { $2 }
body2 :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
: '{' top '}' { $2 }
| missing_module_keyword top close { $2 }
top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
: importdecls { (reverse $1,[]) }
| importdecls ';' cvtopdecls { (reverse $1,$3) }
| cvtopdecls { ([],$1) }
cvtopdecls :: { [LHsDecl RdrName] }
: topdecls { cvTopDecls $1 }
-----------------------------------------------------------------------------
-- Module declaration & imports only
header :: { Located (HsModule RdrName) }
: maybedocheader 'module' modid maybemodwarning maybeexports 'where' header_body
{% fileSrcSpan >>= \ loc ->
return (L loc (HsModule (Just $3) $5 $7 [] $4 $1
))}
| header_body2
{% fileSrcSpan >>= \ loc ->
return (L loc (HsModule Nothing Nothing $1 [] Nothing
Nothing)) }
header_body :: { [LImportDecl RdrName] }
: '{' importdecls { $2 }
| vocurly importdecls { $2 }
header_body2 :: { [LImportDecl RdrName] }
: '{' importdecls { $2 }
| missing_module_keyword importdecls { $2 }
-----------------------------------------------------------------------------
-- The Export List
maybeexports :: { Maybe [LIE RdrName] }
: '(' exportlist ')' { Just $2 }
| {- empty -} { Nothing }
exportlist :: { [LIE RdrName] }
: expdoclist ',' expdoclist { $1 ++ $3 }
| exportlist1 { $1 }
exportlist1 :: { [LIE RdrName] }
: expdoclist export expdoclist ',' exportlist { $1 ++ ($2 : $3) ++ $5 }
| expdoclist export expdoclist { $1 ++ ($2 : $3) }
| expdoclist { $1 }
expdoclist :: { [LIE RdrName] }
: exp_doc expdoclist { $1 : $2 }
| {- empty -} { [] }
exp_doc :: { LIE RdrName }
: docsection { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
| docnamed { L1 (IEDocNamed ((fst . unLoc) $1)) }
| docnext { L1 (IEDoc (unLoc $1)) }
-- No longer allow things like [] and (,,,) to be exported
-- They are built in syntax, always available
export :: { LIE RdrName }
: qcname_ext export_subspec { LL (mkModuleImpExp (unLoc $1)
(unLoc $2)) }
| 'module' modid { LL (IEModuleContents (unLoc $2)) }
export_subspec :: { Located ImpExpSubSpec }
: {- empty -} { L0 ImpExpAbs }
| '(' '..' ')' { LL ImpExpAll }
| '(' ')' { LL (ImpExpList []) }
| '(' qcnames ')' { LL (ImpExpList (reverse $2)) }
qcnames :: { [RdrName] } -- A reversed list
: qcnames ',' qcname_ext { unLoc $3 : $1 }
| qcname_ext { [unLoc $1] }
qcname_ext :: { Located RdrName } -- Variable or data constructor
-- or tagged type constructor
: qcname { $1 }
| 'type' qcname {% mkTypeImpExp (LL (unLoc $2)) }
-- Cannot pull into qcname_ext, as qcname is also used in expression.
qcname :: { Located RdrName } -- Variable or data constructor
: qvar { $1 }
| qcon { $1 }
-----------------------------------------------------------------------------
-- Import Declarations
-- import decls can be *empty*, or even just a string of semicolons
-- whereas topdecls must contain at least one topdecl.
importdecls :: { [LImportDecl RdrName] }
: importdecls ';' importdecl { $3 : $1 }
| importdecls ';' { $1 }
| importdecl { [ $1 ] }
| {- empty -} { [] }
importdecl :: { LImportDecl RdrName }
: 'import' maybe_src maybe_safe optqualified maybe_pkg modid maybeas maybeimpspec
{ L (comb4 $1 $6 $7 $8) $
ImportDecl { ideclName = $6, ideclPkgQual = $5
, ideclSource = $2, ideclSafe = $3
, ideclQualified = $4, ideclImplicit = False
, ideclAs = unLoc $7, ideclHiding = unLoc $8 } }
maybe_src :: { IsBootInterface }
: '{-# SOURCE' '#-}' { True }
| {- empty -} { False }
maybe_safe :: { Bool }
: 'safe' { True }
| {- empty -} { False }
maybe_pkg :: { Maybe FastString }
: STRING { Just (getSTRING $1) }
| {- empty -} { Nothing }
optqualified :: { Bool }
: 'qualified' { True }
| {- empty -} { False }
maybeas :: { Located (Maybe ModuleName) }
: 'as' modid { LL (Just (unLoc $2)) }
| {- empty -} { noLoc Nothing }
maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
: impspec { L1 (Just (unLoc $1)) }
| {- empty -} { noLoc Nothing }
impspec :: { Located (Bool, [LIE RdrName]) }
: '(' exportlist ')' { LL (False, $2) }
| 'hiding' '(' exportlist ')' { LL (True, $3) }
-----------------------------------------------------------------------------
-- Fixity Declarations
prec :: { Int }
: {- empty -} { 9 }
| INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
infix :: { Located FixityDirection }
: 'infix' { L1 InfixN }
| 'infixl' { L1 InfixL }
| 'infixr' { L1 InfixR }
ops :: { Located [Located RdrName] }
: ops ',' op { LL ($3 : unLoc $1) }
| op { L1 [$1] }
-----------------------------------------------------------------------------
-- Top-Level Declarations
topdecls :: { OrdList (LHsDecl RdrName) }
: topdecls ';' topdecl { $1 `appOL` $3 }
| topdecls ';' { $1 }
| topdecl { $1 }
topdecl :: { OrdList (LHsDecl RdrName) }
: cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
| ty_decl { unitOL (L1 (TyClD (unLoc $1))) }
| inst_decl { unitOL (L1 (InstD (unLoc $1))) }
| stand_alone_deriving { unitOL (LL (DerivD (unLoc $1))) }
| 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
| 'foreign' fdecl { unitOL (LL (unLoc $2)) }
| '{-# DEPRECATED' deprecations '#-}' { $2 }
| '{-# WARNING' warnings '#-}' { $2 }
| '{-# RULES' rules '#-}' { $2 }
| '{-# VECTORISE_SCALAR' qvar '#-}' { unitOL $ LL $ VectD (HsVect $2 Nothing) }
| '{-# VECTORISE' qvar '=' exp '#-}' { unitOL $ LL $ VectD (HsVect $2 (Just $4)) }
| '{-# NOVECTORISE' qvar '#-}' { unitOL $ LL $ VectD (HsNoVect $2) }
| '{-# VECTORISE' 'type' gtycon '#-}'
{ unitOL $ LL $
VectD (HsVectTypeIn False $3 Nothing) }
| '{-# VECTORISE_SCALAR' 'type' gtycon '#-}'
{ unitOL $ LL $
VectD (HsVectTypeIn True $3 Nothing) }
| '{-# VECTORISE' 'type' gtycon '=' gtycon '#-}'
{ unitOL $ LL $
VectD (HsVectTypeIn False $3 (Just $5)) }
| '{-# VECTORISE_SCALAR' 'type' gtycon '=' gtycon '#-}'
{ unitOL $ LL $
VectD (HsVectTypeIn True $3 (Just $5)) }
| '{-# VECTORISE' 'class' gtycon '#-}' { unitOL $ LL $ VectD (HsVectClassIn $3) }
| '{-# VECTORISE_SCALAR' 'instance' type '#-}'
{ unitOL $ LL $ VectD (HsVectInstIn $3) }
| annotation { unitOL $1 }
| decl { unLoc $1 }
-- Template Haskell Extension
-- The $(..) form is one possible form of infixexp
-- but we treat an arbitrary expression just as if
-- it had a $(..) wrapped around it
| infixexp { unitOL (LL $ mkTopSpliceDecl $1) }
-- Type classes
--
cl_decl :: { LTyClDecl RdrName }
: 'class' tycl_hdr fds where_cls {% mkClassDecl (comb4 $1 $2 $3 $4) $2 $3 $4 }
-- Type declarations (toplevel)
--
ty_decl :: { LTyClDecl RdrName }
-- ordinary type synonyms
: 'type' type '=' ctypedoc
-- Note ctype, not sigtype, on the right of '='
-- We allow an explicit for-all but we don't insert one
-- in type Foo a = (b,b)
-- Instead we just say b is out of scope
--
-- Note the use of type for the head; this allows
-- infix type constructors to be declared
{% mkTySynonym (comb2 $1 $4) $2 $4 }
-- type family declarations
| 'type' 'family' type opt_kind_sig
-- Note the use of type for the head; this allows
-- infix type constructors to be declared
{% mkTyFamily (comb3 $1 $3 $4) TypeFamily $3 (unLoc $4) }
-- ordinary data type or newtype declaration
| data_or_newtype capi_ctype tycl_hdr constrs deriving
{% mkTyData (comb4 $1 $3 $4 $5) (unLoc $1) $2 $3
Nothing (reverse (unLoc $4)) (unLoc $5) }
-- We need the location on tycl_hdr in case
-- constrs and deriving are both empty
-- ordinary GADT declaration
| data_or_newtype capi_ctype tycl_hdr opt_kind_sig
gadt_constrlist
deriving
{% mkTyData (comb4 $1 $3 $5 $6) (unLoc $1) $2 $3
(unLoc $4) (unLoc $5) (unLoc $6) }
-- We need the location on tycl_hdr in case
-- constrs and deriving are both empty
-- data/newtype family
| 'data' 'family' type opt_kind_sig
{% mkTyFamily (comb3 $1 $2 $4) DataFamily $3 (unLoc $4) }
inst_decl :: { LInstDecl RdrName }
: 'instance' inst_type where_inst
{ let (binds, sigs, _, ats, _) = cvBindsAndSigs (unLoc $3)
in L (comb3 $1 $2 $3) (ClsInstD { cid_poly_ty = $2, cid_binds = binds
, cid_sigs = sigs, cid_fam_insts = ats }) }
-- type instance declarations
| 'type' 'instance' type '=' ctype
-- Note the use of type for the head; this allows
-- infix type constructors and type patterns
{% do { L loc d <- mkFamInstSynonym (comb2 $1 $5) $3 $5
; return (L loc (FamInstD { lid_inst = d })) } }
-- data/newtype instance declaration
| data_or_newtype 'instance' tycl_hdr constrs deriving
{% do { L loc d <- mkFamInstData (comb4 $1 $3 $4 $5) (unLoc $1) Nothing $3
Nothing (reverse (unLoc $4)) (unLoc $5)
; return (L loc (FamInstD { lid_inst = d })) } }
-- GADT instance declaration
| data_or_newtype 'instance' tycl_hdr opt_kind_sig
gadt_constrlist
deriving
{% do { L loc d <- mkFamInstData (comb4 $1 $3 $5 $6) (unLoc $1) Nothing $3
(unLoc $4) (unLoc $5) (unLoc $6)
; return (L loc (FamInstD { lid_inst = d })) } }
-- Associated type family declarations
--
-- * They have a different syntax than on the toplevel (no family special
-- identifier).
--
-- * They also need to be separate from instances; otherwise, data family
-- declarations without a kind signature cause parsing conflicts with empty
-- data declarations.
--
at_decl_cls :: { LHsDecl RdrName }
-- family declarations
: 'type' type opt_kind_sig
-- Note the use of type for the head; this allows
-- infix type constructors to be declared.
{% do { L loc decl <- mkTyFamily (comb3 $1 $2 $3) TypeFamily $2 (unLoc $3)
; return (L loc (TyClD decl)) } }
| 'data' type opt_kind_sig
{% do { L loc decl <- mkTyFamily (comb3 $1 $2 $3) DataFamily $2 (unLoc $3)
; return (L loc (TyClD decl)) } }
-- default type instance
| 'type' type '=' ctype
-- Note the use of type for the head; this allows
-- infix type constructors and type patterns
{% do { L loc fid <- mkFamInstSynonym (comb2 $1 $4) $2 $4
; return (L loc (InstD (FamInstD { lid_inst = fid }))) } }
-- Associated type instances
--
at_decl_inst :: { LFamInstDecl RdrName }
-- type instance declarations
: 'type' type '=' ctype
-- Note the use of type for the head; this allows
-- infix type constructors and type patterns
{% mkFamInstSynonym (comb2 $1 $4) $2 $4 }
-- data/newtype instance declaration
| data_or_newtype capi_ctype tycl_hdr constrs deriving
{% mkFamInstData (comb4 $1 $3 $4 $5) (unLoc $1) $2 $3
Nothing (reverse (unLoc $4)) (unLoc $5) }
-- GADT instance declaration
| data_or_newtype capi_ctype tycl_hdr opt_kind_sig
gadt_constrlist
deriving
{% mkFamInstData (comb4 $1 $3 $5 $6) (unLoc $1) $2 $3
(unLoc $4) (unLoc $5) (unLoc $6) }
data_or_newtype :: { Located NewOrData }
: 'data' { L1 DataType }
| 'newtype' { L1 NewType }
opt_kind_sig :: { Located (Maybe (LHsKind RdrName)) }
: { noLoc Nothing }
| '::' kind { LL (Just $2) }
-- tycl_hdr parses the header of a class or data type decl,
-- which takes the form
-- T a b
-- Eq a => T a
-- (Eq a, Ord b) => T a b
-- T Int [a] -- for associated types
-- Rather a lot of inlining here, else we get reduce/reduce errors
tycl_hdr :: { Located (Maybe (LHsContext RdrName), LHsType RdrName) }
: context '=>' type { LL (Just $1, $3) }
| type { L1 (Nothing, $1) }
capi_ctype :: { Maybe CType }
capi_ctype : '{-# CTYPE' STRING STRING '#-}' { Just (CType (Just (Header (getSTRING $2))) (getSTRING $3)) }
| '{-# CTYPE' STRING '#-}' { Just (CType Nothing (getSTRING $2)) }
| { Nothing }
-----------------------------------------------------------------------------
-- Stand-alone deriving
-- Glasgow extension: stand-alone deriving declarations
stand_alone_deriving :: { LDerivDecl RdrName }
: 'deriving' 'instance' inst_type { LL (DerivDecl $3) }
-----------------------------------------------------------------------------
-- Nested declarations
-- Declaration in class bodies
--
decl_cls :: { Located (OrdList (LHsDecl RdrName)) }
decl_cls : at_decl_cls { LL (unitOL $1) }
| decl { $1 }
-- A 'default' signature used with the generic-programming extension
| 'default' infixexp '::' sigtypedoc
{% do { (TypeSig l ty) <- checkValSig $2 $4
; return (LL $ unitOL (LL $ SigD (GenericSig l ty))) } }
decls_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
: decls_cls ';' decl_cls { LL (unLoc $1 `appOL` unLoc $3) }
| decls_cls ';' { LL (unLoc $1) }
| decl_cls { $1 }
| {- empty -} { noLoc nilOL }
decllist_cls
:: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
: '{' decls_cls '}' { LL (unLoc $2) }
| vocurly decls_cls close { $2 }
-- Class body
--
where_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
-- No implicit parameters
-- May have type declarations
: 'where' decllist_cls { LL (unLoc $2) }
| {- empty -} { noLoc nilOL }
-- Declarations in instance bodies
--
decl_inst :: { Located (OrdList (LHsDecl RdrName)) }
decl_inst : at_decl_inst { LL (unitOL (L1 (InstD (FamInstD { lid_inst = unLoc $1 })))) }
| decl { $1 }
decls_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
: decls_inst ';' decl_inst { LL (unLoc $1 `appOL` unLoc $3) }
| decls_inst ';' { LL (unLoc $1) }
| decl_inst { $1 }
| {- empty -} { noLoc nilOL }
decllist_inst
:: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
: '{' decls_inst '}' { LL (unLoc $2) }
| vocurly decls_inst close { $2 }
-- Instance body
--
where_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
-- No implicit parameters
-- May have type declarations
: 'where' decllist_inst { LL (unLoc $2) }
| {- empty -} { noLoc nilOL }
-- Declarations in binding groups other than classes and instances
--
decls :: { Located (OrdList (LHsDecl RdrName)) }
: decls ';' decl { let { this = unLoc $3;
rest = unLoc $1;
these = rest `appOL` this }
in rest `seq` this `seq` these `seq`
LL these }
| decls ';' { LL (unLoc $1) }
| decl { $1 }
| {- empty -} { noLoc nilOL }
decllist :: { Located (OrdList (LHsDecl RdrName)) }
: '{' decls '}' { LL (unLoc $2) }
| vocurly decls close { $2 }
-- Binding groups other than those of class and instance declarations
--
binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
-- No type declarations
: decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
| '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyTcEvBinds)) }
| vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyTcEvBinds)) }
wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
-- No type declarations
: 'where' binds { LL (unLoc $2) }
| {- empty -} { noLoc emptyLocalBinds }
-----------------------------------------------------------------------------
-- Transformation Rules
rules :: { OrdList (LHsDecl RdrName) }
: rules ';' rule { $1 `snocOL` $3 }
| rules ';' { $1 }
| rule { unitOL $1 }
| {- empty -} { nilOL }
rule :: { LHsDecl RdrName }
: STRING activation rule_forall infixexp '=' exp
{ LL $ RuleD (HsRule (getSTRING $1)
($2 `orElse` AlwaysActive)
$3 $4 placeHolderNames $6 placeHolderNames) }
activation :: { Maybe Activation }
: {- empty -} { Nothing }
| explicit_activation { Just $1 }
explicit_activation :: { Activation } -- In brackets
: '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
| '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
rule_forall :: { [RuleBndr RdrName] }
: 'forall' rule_var_list '.' { $2 }
| {- empty -} { [] }
rule_var_list :: { [RuleBndr RdrName] }
: rule_var { [$1] }
| rule_var rule_var_list { $1 : $2 }
rule_var :: { RuleBndr RdrName }
: varid { RuleBndr $1 }
| '(' varid '::' ctype ')' { RuleBndrSig $2 (mkHsWithBndrs $4) }
-----------------------------------------------------------------------------
-- Warnings and deprecations (c.f. rules)
warnings :: { OrdList (LHsDecl RdrName) }
: warnings ';' warning { $1 `appOL` $3 }
| warnings ';' { $1 }
| warning { $1 }
| {- empty -} { nilOL }
-- SUP: TEMPORARY HACK, not checking for `module Foo'
warning :: { OrdList (LHsDecl RdrName) }
: namelist strings
{ toOL [ LL $ WarningD (Warning n (WarningTxt $ unLoc $2))
| n <- unLoc $1 ] }
deprecations :: { OrdList (LHsDecl RdrName) }
: deprecations ';' deprecation { $1 `appOL` $3 }
| deprecations ';' { $1 }
| deprecation { $1 }
| {- empty -} { nilOL }
-- SUP: TEMPORARY HACK, not checking for `module Foo'
deprecation :: { OrdList (LHsDecl RdrName) }
: namelist strings
{ toOL [ LL $ WarningD (Warning n (DeprecatedTxt $ unLoc $2))
| n <- unLoc $1 ] }
strings :: { Located [FastString] }
: STRING { L1 [getSTRING $1] }
| '[' stringlist ']' { LL $ fromOL (unLoc $2) }
stringlist :: { Located (OrdList FastString) }
: stringlist ',' STRING { LL (unLoc $1 `snocOL` getSTRING $3) }
| STRING { LL (unitOL (getSTRING $1)) }
-----------------------------------------------------------------------------
-- Annotations
annotation :: { LHsDecl RdrName }
: '{-# ANN' name_var aexp '#-}' { LL (AnnD $ HsAnnotation (ValueAnnProvenance (unLoc $2)) $3) }
| '{-# ANN' 'type' tycon aexp '#-}' { LL (AnnD $ HsAnnotation (TypeAnnProvenance (unLoc $3)) $4) }
| '{-# ANN' 'module' aexp '#-}' { LL (AnnD $ HsAnnotation ModuleAnnProvenance $3) }
-----------------------------------------------------------------------------
-- Foreign import and export declarations
fdecl :: { LHsDecl RdrName }
fdecl : 'import' callconv safety fspec
{% mkImport $2 $3 (unLoc $4) >>= return.LL }
| 'import' callconv fspec
{% do { d <- mkImport $2 PlaySafe (unLoc $3);
return (LL d) } }
| 'export' callconv fspec
{% mkExport $2 (unLoc $3) >>= return.LL }
callconv :: { CCallConv }
: 'stdcall' { StdCallConv }
| 'ccall' { CCallConv }
| 'capi' { CApiConv }
| 'prim' { PrimCallConv}
safety :: { Safety }
: 'unsafe' { PlayRisky }
| 'safe' { PlaySafe }
| 'interruptible' { PlayInterruptible }
fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
: STRING var '::' sigtypedoc { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
| var '::' sigtypedoc { LL (noLoc nilFS, $1, $3) }
-- if the entity string is missing, it defaults to the empty string;
-- the meaning of an empty entity string depends on the calling
-- convention
-----------------------------------------------------------------------------
-- Type signatures
opt_sig :: { Maybe (LHsType RdrName) }
: {- empty -} { Nothing }
| '::' sigtype { Just $2 }
opt_asig :: { Maybe (LHsType RdrName) }
: {- empty -} { Nothing }
| '::' atype { Just $2 }
sigtype :: { LHsType RdrName } -- Always a HsForAllTy,
-- to tell the renamer where to generalise
: ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
-- Wrap an Implicit forall if there isn't one there already
sigtypedoc :: { LHsType RdrName } -- Always a HsForAllTy
: ctypedoc { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
-- Wrap an Implicit forall if there isn't one there already
sig_vars :: { Located [Located RdrName] }
: sig_vars ',' var { LL ($3 : unLoc $1) }
| var { L1 [$1] }
sigtypes1 :: { [LHsType RdrName] } -- Always HsForAllTys
: sigtype { [ $1 ] }
| sigtype ',' sigtypes1 { $1 : $3 }
-----------------------------------------------------------------------------
-- Types
infixtype :: { LHsType RdrName }
: btype qtyconop type { LL $ mkHsOpTy $1 $2 $3 }
| btype tyvarop type { LL $ mkHsOpTy $1 $2 $3 }
strict_mark :: { Located HsBang }
: '!' { L1 HsStrict }
| '{-# UNPACK' '#-}' '!' { LL HsUnpack }
| '{-# NOUNPACK' '#-}' '!' { LL HsNoUnpack }
-- A ctype is a for-all type