2 -- ---------------------------------------------------------------------------
3 -- (c) The University of Glasgow 1997-2003
7 -- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
8 -- ---------------------------------------------------------------------------
11 {-# OPTIONS -Wwarn -w #-}
12 -- The above warning supression flag is a temporary kludge.
13 -- While working on this module you are encouraged to remove it and fix
14 -- any warnings in the module. See
15 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
18 {-# OPTIONS_GHC -O0 -fno-ignore-interface-pragmas #-}
20 Careful optimisation of the parser: we don't want to throw everything
21 at it, because that takes too long and doesn't buy much, but we do want
22 to inline certain key external functions, so we instruct GHC not to
23 throw away inlinings as it would normally do in -O0 mode.
26 module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
31 import HscTypes ( IsBootInterface, WarningTxt(..) )
34 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
35 unboxedSingletonTyCon, unboxedSingletonDataCon,
36 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
37 import Type ( funTyCon )
38 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
39 CCallConv(..), CCallTarget(..), defaultCCallConv
41 import OccName ( varName, dataName, tcClsName, tvName )
42 import DataCon ( DataCon, dataConName )
43 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
44 SrcSpan, combineLocs, srcLocFile,
47 import StaticFlags ( opt_SccProfilingOn, opt_Hpc )
48 import Type ( Kind, mkArrowKind, liftedTypeKind, unliftedTypeKind )
49 import Class ( FunDep )
50 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
51 Activation(..), RuleMatchInfo(..), defaultInlineSpec )
55 import {-# SOURCE #-} HaddockLex hiding ( Token )
59 import Maybes ( orElse )
62 import Control.Monad ( unless )
65 import Control.Monad ( mplus )
69 -----------------------------------------------------------------------------
72 Conflicts: 33 shift/reduce
75 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
76 would think the two should never occur in the same context.
80 -----------------------------------------------------------------------------
83 Conflicts: 34 shift/reduce
86 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
87 would think the two should never occur in the same context.
91 -----------------------------------------------------------------------------
94 Conflicts: 32 shift/reduce
97 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
98 would think the two should never occur in the same context.
102 -----------------------------------------------------------------------------
105 Conflicts: 37 shift/reduce
108 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
109 would think the two should never occur in the same context.
113 -----------------------------------------------------------------------------
114 Conflicts: 38 shift/reduce (1.25)
116 10 for abiguity in 'if x then y else z + 1' [State 178]
117 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
118 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
120 1 for ambiguity in 'if x then y else z :: T' [State 178]
121 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
123 4 for ambiguity in 'if x then y else z -< e' [State 178]
124 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
125 There are four such operators: -<, >-, -<<, >>-
128 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
129 Which of these two is intended?
131 (x::T) -> T -- Rhs is T
134 (x::T -> T) -> .. -- Rhs is ...
136 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
139 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
140 Same duplication between states 11 and 253 as the previous case
142 1 for ambiguity in 'let ?x ...' [State 329]
143 the parser can't tell whether the ?x is the lhs of a normal binding or
144 an implicit binding. Fortunately resolving as shift gives it the only
145 sensible meaning, namely the lhs of an implicit binding.
147 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
148 we don't know whether the '[' starts the activation or not: it
149 might be the start of the declaration with the activation being
150 empty. --SDM 1/4/2002
152 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
153 since 'forall' is a valid variable name, we don't know whether
154 to treat a forall on the input as the beginning of a quantifier
155 or the beginning of the rule itself. Resolving to shift means
156 it's always treated as a quantifier, hence the above is disallowed.
157 This saves explicitly defining a grammar for the rule lhs that
158 doesn't include 'forall'.
160 1 for ambiguity when the source file starts with "-- | doc". We need another
161 token of lookahead to determine if a top declaration or the 'module' keyword
162 follows. Shift parses as if the 'module' keyword follows.
164 -- ---------------------------------------------------------------------------
165 -- Adding location info
167 This is done in a stylised way using the three macros below, L0, L1
168 and LL. Each of these macros can be thought of as having type
170 L0, L1, LL :: a -> Located a
172 They each add a SrcSpan to their argument.
174 L0 adds 'noSrcSpan', used for empty productions
175 -- This doesn't seem to work anymore -=chak
177 L1 for a production with a single token on the lhs. Grabs the SrcSpan
180 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
181 the first and last tokens.
183 These suffice for the majority of cases. However, we must be
184 especially careful with empty productions: LL won't work if the first
185 or last token on the lhs can represent an empty span. In these cases,
186 we have to calculate the span using more of the tokens from the lhs, eg.
188 | 'newtype' tycl_hdr '=' newconstr deriving
190 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
192 We provide comb3 and comb4 functions which are useful in such cases.
194 Be careful: there's no checking that you actually got this right, the
195 only symptom will be that the SrcSpans of your syntax will be
199 * We must expand these macros *before* running Happy, which is why this file is
200 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
202 #define L0 L noSrcSpan
203 #define L1 sL (getLoc $1)
204 #define LL sL (comb2 $1 $>)
206 -- -----------------------------------------------------------------------------
211 '_' { L _ ITunderscore } -- Haskell keywords
213 'case' { L _ ITcase }
214 'class' { L _ ITclass }
215 'data' { L _ ITdata }
216 'default' { L _ ITdefault }
217 'deriving' { L _ ITderiving }
219 'else' { L _ ITelse }
220 'hiding' { L _ IThiding }
222 'import' { L _ ITimport }
224 'infix' { L _ ITinfix }
225 'infixl' { L _ ITinfixl }
226 'infixr' { L _ ITinfixr }
227 'instance' { L _ ITinstance }
229 'module' { L _ ITmodule }
230 'newtype' { L _ ITnewtype }
232 'qualified' { L _ ITqualified }
233 'then' { L _ ITthen }
234 'type' { L _ ITtype }
235 'where' { L _ ITwhere }
236 '_scc_' { L _ ITscc } -- ToDo: remove
238 'forall' { L _ ITforall } -- GHC extension keywords
239 'foreign' { L _ ITforeign }
240 'export' { L _ ITexport }
241 'label' { L _ ITlabel }
242 'dynamic' { L _ ITdynamic }
243 'safe' { L _ ITsafe }
244 'threadsafe' { L _ ITthreadsafe } -- ToDo: remove deprecated alias
245 'unsafe' { L _ ITunsafe }
247 'family' { L _ ITfamily }
248 'stdcall' { L _ ITstdcallconv }
249 'ccall' { L _ ITccallconv }
250 'prim' { L _ ITprimcallconv }
251 'proc' { L _ ITproc } -- for arrow notation extension
252 'rec' { L _ ITrec } -- for arrow notation extension
253 'group' { L _ ITgroup } -- for list transform extension
254 'by' { L _ ITby } -- for list transform extension
255 'using' { L _ ITusing } -- for list transform extension
257 '{-# INLINE' { L _ (ITinline_prag _) }
258 '{-# INLINE_CONLIKE' { L _ (ITinline_conlike_prag _) }
259 '{-# SPECIALISE' { L _ ITspec_prag }
260 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
261 '{-# SOURCE' { L _ ITsource_prag }
262 '{-# RULES' { L _ ITrules_prag }
263 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
264 '{-# SCC' { L _ ITscc_prag }
265 '{-# GENERATED' { L _ ITgenerated_prag }
266 '{-# DEPRECATED' { L _ ITdeprecated_prag }
267 '{-# WARNING' { L _ ITwarning_prag }
268 '{-# UNPACK' { L _ ITunpack_prag }
269 '{-# ANN' { L _ ITann_prag }
270 '#-}' { L _ ITclose_prag }
272 '..' { L _ ITdotdot } -- reserved symbols
274 '::' { L _ ITdcolon }
278 '<-' { L _ ITlarrow }
279 '->' { L _ ITrarrow }
282 '=>' { L _ ITdarrow }
286 '-<' { L _ ITlarrowtail } -- for arrow notation
287 '>-' { L _ ITrarrowtail } -- for arrow notation
288 '-<<' { L _ ITLarrowtail } -- for arrow notation
289 '>>-' { L _ ITRarrowtail } -- for arrow notation
292 '{' { L _ ITocurly } -- special symbols
294 '{|' { L _ ITocurlybar }
295 '|}' { L _ ITccurlybar }
296 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
297 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
300 '[:' { L _ ITopabrack }
301 ':]' { L _ ITcpabrack }
304 '(#' { L _ IToubxparen }
305 '#)' { L _ ITcubxparen }
306 '(|' { L _ IToparenbar }
307 '|)' { L _ ITcparenbar }
310 '`' { L _ ITbackquote }
312 VARID { L _ (ITvarid _) } -- identifiers
313 CONID { L _ (ITconid _) }
314 VARSYM { L _ (ITvarsym _) }
315 CONSYM { L _ (ITconsym _) }
316 QVARID { L _ (ITqvarid _) }
317 QCONID { L _ (ITqconid _) }
318 QVARSYM { L _ (ITqvarsym _) }
319 QCONSYM { L _ (ITqconsym _) }
320 PREFIXQVARSYM { L _ (ITprefixqvarsym _) }
321 PREFIXQCONSYM { L _ (ITprefixqconsym _) }
323 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
325 CHAR { L _ (ITchar _) }
326 STRING { L _ (ITstring _) }
327 INTEGER { L _ (ITinteger _) }
328 RATIONAL { L _ (ITrational _) }
330 PRIMCHAR { L _ (ITprimchar _) }
331 PRIMSTRING { L _ (ITprimstring _) }
332 PRIMINTEGER { L _ (ITprimint _) }
333 PRIMWORD { L _ (ITprimword _) }
334 PRIMFLOAT { L _ (ITprimfloat _) }
335 PRIMDOUBLE { L _ (ITprimdouble _) }
337 DOCNEXT { L _ (ITdocCommentNext _) }
338 DOCPREV { L _ (ITdocCommentPrev _) }
339 DOCNAMED { L _ (ITdocCommentNamed _) }
340 DOCSECTION { L _ (ITdocSection _ _) }
343 '[|' { L _ ITopenExpQuote }
344 '[p|' { L _ ITopenPatQuote }
345 '[t|' { L _ ITopenTypQuote }
346 '[d|' { L _ ITopenDecQuote }
347 '|]' { L _ ITcloseQuote }
348 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
349 '$(' { L _ ITparenEscape } -- $( exp )
350 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
351 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
352 TH_QUASIQUOTE { L _ (ITquasiQuote _) }
354 %monad { P } { >>= } { return }
355 %lexer { lexer } { L _ ITeof }
356 %name parseModule module
357 %name parseStmt maybe_stmt
358 %name parseIdentifier identifier
359 %name parseType ctype
360 %partial parseHeader header
361 %tokentype { (Located Token) }
364 -----------------------------------------------------------------------------
365 -- Identifiers; one of the entry points
366 identifier :: { Located RdrName }
371 | '(' '->' ')' { LL $ getRdrName funTyCon }
373 -----------------------------------------------------------------------------
376 -- The place for module deprecation is really too restrictive, but if it
377 -- was allowed at its natural place just before 'module', we get an ugly
378 -- s/r conflict with the second alternative. Another solution would be the
379 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
380 -- either, and DEPRECATED is only expected to be used by people who really
381 -- know what they are doing. :-)
383 module :: { Located (HsModule RdrName) }
384 : maybedocheader 'module' modid maybemodwarning maybeexports 'where' body
385 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
386 return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4
389 {% fileSrcSpan >>= \ loc ->
390 return (L loc (HsModule Nothing Nothing
391 (fst $1) (snd $1) Nothing emptyHaddockModInfo
394 maybedocheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
395 : moduleheader { $1 }
396 | {- empty -} { (emptyHaddockModInfo, Nothing) }
398 missing_module_keyword :: { () }
399 : {- empty -} {% pushCurrentContext }
401 maybemodwarning :: { Maybe WarningTxt }
402 : '{-# DEPRECATED' STRING '#-}' { Just (DeprecatedTxt (getSTRING $2)) }
403 | '{-# WARNING' STRING '#-}' { Just (WarningTxt (getSTRING $2)) }
404 | {- empty -} { Nothing }
406 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
408 | vocurly top close { $2 }
410 body2 :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
412 | missing_module_keyword top close { $2 }
414 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
415 : importdecls { (reverse $1,[]) }
416 | importdecls ';' cvtopdecls { (reverse $1,$3) }
417 | cvtopdecls { ([],$1) }
419 cvtopdecls :: { [LHsDecl RdrName] }
420 : topdecls { cvTopDecls $1 }
422 -----------------------------------------------------------------------------
423 -- Module declaration & imports only
425 header :: { Located (HsModule RdrName) }
426 : maybedocheader 'module' modid maybemodwarning maybeexports 'where' header_body
427 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
428 return (L loc (HsModule (Just $3) $5 $7 [] $4
430 | missing_module_keyword importdecls
431 {% fileSrcSpan >>= \ loc ->
432 return (L loc (HsModule Nothing Nothing $2 [] Nothing
433 emptyHaddockModInfo Nothing)) }
435 header_body :: { [LImportDecl RdrName] }
436 : '{' importdecls { $2 }
437 | vocurly importdecls { $2 }
439 -----------------------------------------------------------------------------
442 maybeexports :: { Maybe [LIE RdrName] }
443 : '(' exportlist ')' { Just $2 }
444 | {- empty -} { Nothing }
446 exportlist :: { [LIE RdrName] }
447 : expdoclist ',' expdoclist { $1 ++ $3 }
450 exportlist1 :: { [LIE RdrName] }
451 : expdoclist export expdoclist ',' exportlist { $1 ++ ($2 : $3) ++ $5 }
452 | expdoclist export expdoclist { $1 ++ ($2 : $3) }
455 expdoclist :: { [LIE RdrName] }
456 : exp_doc expdoclist { $1 : $2 }
459 exp_doc :: { LIE RdrName }
460 : docsection { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
461 | docnamed { L1 (IEDocNamed ((fst . unLoc) $1)) }
462 | docnext { L1 (IEDoc (unLoc $1)) }
464 -- No longer allow things like [] and (,,,) to be exported
465 -- They are built in syntax, always available
466 export :: { LIE RdrName }
467 : qvar { L1 (IEVar (unLoc $1)) }
468 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
469 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
470 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
471 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
472 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
474 qcnames :: { [RdrName] }
475 : qcnames ',' qcname_ext { unLoc $3 : $1 }
476 | qcname_ext { [unLoc $1] }
478 qcname_ext :: { Located RdrName } -- Variable or data constructor
479 -- or tagged type constructor
481 | 'type' qcon { sL (comb2 $1 $2)
482 (setRdrNameSpace (unLoc $2)
485 -- Cannot pull into qcname_ext, as qcname is also used in expression.
486 qcname :: { Located RdrName } -- Variable or data constructor
490 -----------------------------------------------------------------------------
491 -- Import Declarations
493 -- import decls can be *empty*, or even just a string of semicolons
494 -- whereas topdecls must contain at least one topdecl.
496 importdecls :: { [LImportDecl RdrName] }
497 : importdecls ';' importdecl { $3 : $1 }
498 | importdecls ';' { $1 }
499 | importdecl { [ $1 ] }
502 importdecl :: { LImportDecl RdrName }
503 : 'import' maybe_src optqualified maybe_pkg modid maybeas maybeimpspec
504 { L (comb4 $1 $5 $6 $7) (ImportDecl $5 $4 $2 $3 (unLoc $6) (unLoc $7)) }
506 maybe_src :: { IsBootInterface }
507 : '{-# SOURCE' '#-}' { True }
508 | {- empty -} { False }
510 maybe_pkg :: { Maybe FastString }
511 : STRING { Just (getSTRING $1) }
512 | {- empty -} { Nothing }
514 optqualified :: { Bool }
515 : 'qualified' { True }
516 | {- empty -} { False }
518 maybeas :: { Located (Maybe ModuleName) }
519 : 'as' modid { LL (Just (unLoc $2)) }
520 | {- empty -} { noLoc Nothing }
522 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
523 : impspec { L1 (Just (unLoc $1)) }
524 | {- empty -} { noLoc Nothing }
526 impspec :: { Located (Bool, [LIE RdrName]) }
527 : '(' exportlist ')' { LL (False, $2) }
528 | 'hiding' '(' exportlist ')' { LL (True, $3) }
530 -----------------------------------------------------------------------------
531 -- Fixity Declarations
535 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
537 infix :: { Located FixityDirection }
538 : 'infix' { L1 InfixN }
539 | 'infixl' { L1 InfixL }
540 | 'infixr' { L1 InfixR }
542 ops :: { Located [Located RdrName] }
543 : ops ',' op { LL ($3 : unLoc $1) }
546 -----------------------------------------------------------------------------
547 -- Top-Level Declarations
549 topdecls :: { OrdList (LHsDecl RdrName) }
550 : topdecls ';' topdecl { $1 `appOL` $3 }
551 | topdecls ';' { $1 }
554 topdecl :: { OrdList (LHsDecl RdrName) }
555 : cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
556 | ty_decl { unitOL (L1 (TyClD (unLoc $1))) }
557 | 'instance' inst_type where_inst
558 { let (binds, sigs, ats, _) = cvBindsAndSigs (unLoc $3)
560 unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs ats)))}
561 | stand_alone_deriving { unitOL (LL (DerivD (unLoc $1))) }
562 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
563 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
564 | '{-# DEPRECATED' deprecations '#-}' { $2 }
565 | '{-# WARNING' warnings '#-}' { $2 }
566 | '{-# RULES' rules '#-}' { $2 }
567 | annotation { unitOL $1 }
570 -- Template Haskell Extension
571 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
572 | TH_ID_SPLICE { unitOL (LL $ SpliceD (SpliceDecl $
573 L1 $ HsVar (mkUnqual varName (getTH_ID_SPLICE $1))
578 cl_decl :: { LTyClDecl RdrName }
579 : 'class' tycl_hdr fds where_cls {% mkClassDecl (comb4 $1 $2 $3 $4) $2 $3 $4 }
581 -- Type declarations (toplevel)
583 ty_decl :: { LTyClDecl RdrName }
584 -- ordinary type synonyms
585 : 'type' type '=' ctypedoc
586 -- Note ctype, not sigtype, on the right of '='
587 -- We allow an explicit for-all but we don't insert one
588 -- in type Foo a = (b,b)
589 -- Instead we just say b is out of scope
591 -- Note the use of type for the head; this allows
592 -- infix type constructors to be declared
593 {% mkTySynonym (comb2 $1 $4) False $2 $4 }
595 -- type family declarations
596 | 'type' 'family' type opt_kind_sig
597 -- Note the use of type for the head; this allows
598 -- infix type constructors to be declared
599 {% mkTyFamily (comb3 $1 $3 $4) TypeFamily $3 (unLoc $4) }
601 -- type instance declarations
602 | 'type' 'instance' type '=' ctype
603 -- Note the use of type for the head; this allows
604 -- infix type constructors and type patterns
605 {% mkTySynonym (comb2 $1 $5) True $3 $5 }
607 -- ordinary data type or newtype declaration
608 | data_or_newtype tycl_hdr constrs deriving
609 {% mkTyData (comb4 $1 $2 $3 $4) (unLoc $1) False $2
610 Nothing (reverse (unLoc $3)) (unLoc $4) }
611 -- We need the location on tycl_hdr in case
612 -- constrs and deriving are both empty
614 -- ordinary GADT declaration
615 | data_or_newtype tycl_hdr opt_kind_sig
616 'where' gadt_constrlist
618 {% mkTyData (comb4 $1 $2 $4 $5) (unLoc $1) False $2
619 (unLoc $3) (reverse (unLoc $5)) (unLoc $6) }
620 -- We need the location on tycl_hdr in case
621 -- constrs and deriving are both empty
623 -- data/newtype family
624 | 'data' 'family' type opt_kind_sig
625 {% mkTyFamily (comb3 $1 $2 $4) DataFamily $3 (unLoc $4) }
627 -- data/newtype instance declaration
628 | data_or_newtype 'instance' tycl_hdr constrs deriving
629 {% mkTyData (comb4 $1 $3 $4 $5) (unLoc $1) True $3
630 Nothing (reverse (unLoc $4)) (unLoc $5) }
632 -- GADT instance declaration
633 | data_or_newtype 'instance' tycl_hdr opt_kind_sig
634 'where' gadt_constrlist
636 {% mkTyData (comb4 $1 $3 $6 $7) (unLoc $1) True $3
637 (unLoc $4) (reverse (unLoc $6)) (unLoc $7) }
639 -- Associated type family declarations
641 -- * They have a different syntax than on the toplevel (no family special
644 -- * They also need to be separate from instances; otherwise, data family
645 -- declarations without a kind signature cause parsing conflicts with empty
646 -- data declarations.
648 at_decl_cls :: { LTyClDecl RdrName }
649 -- type family declarations
650 : 'type' type opt_kind_sig
651 -- Note the use of type for the head; this allows
652 -- infix type constructors to be declared
653 {% mkTyFamily (comb3 $1 $2 $3) TypeFamily $2 (unLoc $3) }
655 -- default type instance
656 | 'type' type '=' ctype
657 -- Note the use of type for the head; this allows
658 -- infix type constructors and type patterns
659 {% mkTySynonym (comb2 $1 $4) True $2 $4 }
661 -- data/newtype family declaration
662 | 'data' type opt_kind_sig
663 {% mkTyFamily (comb3 $1 $2 $3) DataFamily $2 (unLoc $3) }
665 -- Associated type instances
667 at_decl_inst :: { LTyClDecl RdrName }
668 -- type instance declarations
669 : 'type' type '=' ctype
670 -- Note the use of type for the head; this allows
671 -- infix type constructors and type patterns
672 {% mkTySynonym (comb2 $1 $4) True $2 $4 }
674 -- data/newtype instance declaration
675 | data_or_newtype tycl_hdr constrs deriving
676 {% mkTyData (comb4 $1 $2 $3 $4) (unLoc $1) True $2
677 Nothing (reverse (unLoc $3)) (unLoc $4) }
679 -- GADT instance declaration
680 | data_or_newtype tycl_hdr opt_kind_sig
681 'where' gadt_constrlist
683 {% mkTyData (comb4 $1 $2 $5 $6) (unLoc $1) True $2
684 (unLoc $3) (reverse (unLoc $5)) (unLoc $6) }
686 data_or_newtype :: { Located NewOrData }
687 : 'data' { L1 DataType }
688 | 'newtype' { L1 NewType }
690 opt_kind_sig :: { Located (Maybe Kind) }
692 | '::' kind { LL (Just (unLoc $2)) }
694 -- tycl_hdr parses the header of a class or data type decl,
695 -- which takes the form
698 -- (Eq a, Ord b) => T a b
699 -- T Int [a] -- for associated types
700 -- Rather a lot of inlining here, else we get reduce/reduce errors
701 tycl_hdr :: { Located (LHsContext RdrName, LHsType RdrName) }
702 : context '=>' type { LL ($1, $3) }
703 | type { L1 (noLoc [], $1) }
705 -----------------------------------------------------------------------------
706 -- Stand-alone deriving
708 -- Glasgow extension: stand-alone deriving declarations
709 stand_alone_deriving :: { LDerivDecl RdrName }
710 : 'deriving' 'instance' inst_type {% checkDerivDecl (LL (DerivDecl $3)) }
712 -----------------------------------------------------------------------------
713 -- Nested declarations
715 -- Declaration in class bodies
717 decl_cls :: { Located (OrdList (LHsDecl RdrName)) }
718 decl_cls : at_decl_cls { LL (unitOL (L1 (TyClD (unLoc $1)))) }
721 decls_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
722 : decls_cls ';' decl_cls { LL (unLoc $1 `appOL` unLoc $3) }
723 | decls_cls ';' { LL (unLoc $1) }
725 | {- empty -} { noLoc nilOL }
729 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
730 : '{' decls_cls '}' { LL (unLoc $2) }
731 | vocurly decls_cls close { $2 }
735 where_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
736 -- No implicit parameters
737 -- May have type declarations
738 : 'where' decllist_cls { LL (unLoc $2) }
739 | {- empty -} { noLoc nilOL }
741 -- Declarations in instance bodies
743 decl_inst :: { Located (OrdList (LHsDecl RdrName)) }
744 decl_inst : at_decl_inst { LL (unitOL (L1 (TyClD (unLoc $1)))) }
747 decls_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
748 : decls_inst ';' decl_inst { LL (unLoc $1 `appOL` unLoc $3) }
749 | decls_inst ';' { LL (unLoc $1) }
751 | {- empty -} { noLoc nilOL }
754 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
755 : '{' decls_inst '}' { LL (unLoc $2) }
756 | vocurly decls_inst close { $2 }
760 where_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
761 -- No implicit parameters
762 -- May have type declarations
763 : 'where' decllist_inst { LL (unLoc $2) }
764 | {- empty -} { noLoc nilOL }
766 -- Declarations in binding groups other than classes and instances
768 decls :: { Located (OrdList (LHsDecl RdrName)) }
769 : decls ';' decl { let { this = unLoc $3;
771 these = rest `appOL` this }
772 in rest `seq` this `seq` these `seq`
774 | decls ';' { LL (unLoc $1) }
776 | {- empty -} { noLoc nilOL }
778 decllist :: { Located (OrdList (LHsDecl RdrName)) }
779 : '{' decls '}' { LL (unLoc $2) }
780 | vocurly decls close { $2 }
782 -- Binding groups other than those of class and instance declarations
784 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
785 -- No type declarations
786 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
787 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
788 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
790 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
791 -- No type declarations
792 : 'where' binds { LL (unLoc $2) }
793 | {- empty -} { noLoc emptyLocalBinds }
796 -----------------------------------------------------------------------------
797 -- Transformation Rules
799 rules :: { OrdList (LHsDecl RdrName) }
800 : rules ';' rule { $1 `snocOL` $3 }
803 | {- empty -} { nilOL }
805 rule :: { LHsDecl RdrName }
806 : STRING activation rule_forall infixexp '=' exp
807 { LL $ RuleD (HsRule (getSTRING $1)
808 ($2 `orElse` AlwaysActive)
809 $3 $4 placeHolderNames $6 placeHolderNames) }
811 activation :: { Maybe Activation }
812 : {- empty -} { Nothing }
813 | explicit_activation { Just $1 }
815 explicit_activation :: { Activation } -- In brackets
816 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
817 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
819 rule_forall :: { [RuleBndr RdrName] }
820 : 'forall' rule_var_list '.' { $2 }
823 rule_var_list :: { [RuleBndr RdrName] }
825 | rule_var rule_var_list { $1 : $2 }
827 rule_var :: { RuleBndr RdrName }
828 : varid { RuleBndr $1 }
829 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
831 -----------------------------------------------------------------------------
832 -- Warnings and deprecations (c.f. rules)
834 warnings :: { OrdList (LHsDecl RdrName) }
835 : warnings ';' warning { $1 `appOL` $3 }
836 | warnings ';' { $1 }
838 | {- empty -} { nilOL }
840 -- SUP: TEMPORARY HACK, not checking for `module Foo'
841 warning :: { OrdList (LHsDecl RdrName) }
843 { toOL [ LL $ WarningD (Warning n (WarningTxt (getSTRING $2)))
846 deprecations :: { OrdList (LHsDecl RdrName) }
847 : deprecations ';' deprecation { $1 `appOL` $3 }
848 | deprecations ';' { $1 }
850 | {- empty -} { nilOL }
852 -- SUP: TEMPORARY HACK, not checking for `module Foo'
853 deprecation :: { OrdList (LHsDecl RdrName) }
855 { toOL [ LL $ WarningD (Warning n (DeprecatedTxt (getSTRING $2)))
858 -----------------------------------------------------------------------------
860 annotation :: { LHsDecl RdrName }
861 : '{-# ANN' name_var aexp '#-}' { LL (AnnD $ HsAnnotation (ValueAnnProvenance (unLoc $2)) $3) }
862 | '{-# ANN' 'type' tycon aexp '#-}' { LL (AnnD $ HsAnnotation (TypeAnnProvenance (unLoc $3)) $4) }
863 | '{-# ANN' 'module' aexp '#-}' { LL (AnnD $ HsAnnotation ModuleAnnProvenance $3) }
866 -----------------------------------------------------------------------------
867 -- Foreign import and export declarations
869 fdecl :: { LHsDecl RdrName }
870 fdecl : 'import' callconv safety fspec
871 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
872 | 'import' callconv fspec
873 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
875 | 'export' callconv fspec
876 {% mkExport $2 (unLoc $3) >>= return.LL }
878 callconv :: { CCallConv }
879 : 'stdcall' { StdCallConv }
880 | 'ccall' { CCallConv }
881 | 'prim' { PrimCallConv}
884 : 'unsafe' { PlayRisky }
885 | 'safe' { PlaySafe False }
886 | 'threadsafe' { PlaySafe True } -- deprecated alias
888 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
889 : STRING var '::' sigtypedoc { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
890 | var '::' sigtypedoc { LL (noLoc nilFS, $1, $3) }
891 -- if the entity string is missing, it defaults to the empty string;
892 -- the meaning of an empty entity string depends on the calling
895 -----------------------------------------------------------------------------
898 opt_sig :: { Maybe (LHsType RdrName) }
899 : {- empty -} { Nothing }
900 | '::' sigtype { Just $2 }
902 opt_asig :: { Maybe (LHsType RdrName) }
903 : {- empty -} { Nothing }
904 | '::' atype { Just $2 }
906 sigtype :: { LHsType RdrName } -- Always a HsForAllTy,
907 -- to tell the renamer where to generalise
908 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
909 -- Wrap an Implicit forall if there isn't one there already
911 sigtypedoc :: { LHsType RdrName } -- Always a HsForAllTy
912 : ctypedoc { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
913 -- Wrap an Implicit forall if there isn't one there already
915 sig_vars :: { Located [Located RdrName] }
916 : sig_vars ',' var { LL ($3 : unLoc $1) }
919 sigtypes1 :: { [LHsType RdrName] } -- Always HsForAllTys
921 | sigtype ',' sigtypes1 { $1 : $3 }
923 -----------------------------------------------------------------------------
926 infixtype :: { LHsType RdrName }
927 : btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
928 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
930 strict_mark :: { Located HsBang }
931 : '!' { L1 HsStrict }
932 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
934 -- A ctype is a for-all type
935 ctype :: { LHsType RdrName }
936 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
937 | context '=>' ctype { LL $ mkImplicitHsForAllTy $1 $3 }
938 -- A type of form (context => type) is an *implicit* HsForAllTy
939 | ipvar '::' type { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
942 ----------------------
943 -- Notes for 'ctypedoc'
944 -- It would have been nice to simplify the grammar by unifying `ctype` and
945 -- ctypedoc` into one production, allowing comments on types everywhere (and
946 -- rejecting them after parsing, where necessary). This is however not possible
947 -- since it leads to ambiguity. The reason is the support for comments on record
949 -- data R = R { field :: Int -- ^ comment on the field }
950 -- If we allow comments on types here, it's not clear if the comment applies
951 -- to 'field' or to 'Int'. So we must use `ctype` to describe the type.
953 ctypedoc :: { LHsType RdrName }
954 : 'forall' tv_bndrs '.' ctypedoc { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
955 | context '=>' ctypedoc { LL $ mkImplicitHsForAllTy $1 $3 }
956 -- A type of form (context => type) is an *implicit* HsForAllTy
957 | ipvar '::' type { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
960 ----------------------
961 -- Notes for 'context'
962 -- We parse a context as a btype so that we don't get reduce/reduce
963 -- errors in ctype. The basic problem is that
965 -- looks so much like a tuple type. We can't tell until we find the =>
967 -- We have the t1 ~ t2 form both in 'context' and in type,
968 -- to permit an individual equational constraint without parenthesis.
969 -- Thus for some reason we allow f :: a~b => blah
970 -- but not f :: ?x::Int => blah
971 context :: { LHsContext RdrName }
972 : btype '~' btype {% checkContext
973 (LL $ HsPredTy (HsEqualP $1 $3)) }
974 | btype {% checkContext $1 }
976 type :: { LHsType RdrName }
978 | btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
979 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
980 | btype '->' ctype { LL $ HsFunTy $1 $3 }
981 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
983 typedoc :: { LHsType RdrName }
985 | btype docprev { LL $ HsDocTy $1 $2 }
986 | btype qtyconop type { LL $ HsOpTy $1 $2 $3 }
987 | btype qtyconop type docprev { LL $ HsDocTy (L (comb3 $1 $2 $3) (HsOpTy $1 $2 $3)) $4 }
988 | btype tyvarop type { LL $ HsOpTy $1 $2 $3 }
989 | btype tyvarop type docprev { LL $ HsDocTy (L (comb3 $1 $2 $3) (HsOpTy $1 $2 $3)) $4 }
990 | btype '->' ctypedoc { LL $ HsFunTy $1 $3 }
991 | btype docprev '->' ctypedoc { LL $ HsFunTy (L (comb2 $1 $2) (HsDocTy $1 $2)) $4 }
992 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
994 btype :: { LHsType RdrName }
995 : btype atype { LL $ HsAppTy $1 $2 }
998 atype :: { LHsType RdrName }
999 : gtycon { L1 (HsTyVar (unLoc $1)) }
1000 | tyvar { L1 (HsTyVar (unLoc $1)) }
1001 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) } -- Constructor sigs only
1002 | '{' fielddecls '}' { LL $ HsRecTy $2 } -- Constructor sigs only
1003 | '(' ctype ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
1004 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
1005 | '[' ctype ']' { LL $ HsListTy $2 }
1006 | '[:' ctype ':]' { LL $ HsPArrTy $2 }
1007 | '(' ctype ')' { LL $ HsParTy $2 }
1008 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 (unLoc $4) }
1009 | '$(' exp ')' { LL $ HsSpliceTy (mkHsSplice $2 ) }
1010 | TH_ID_SPLICE { LL $ HsSpliceTy (mkHsSplice
1011 (L1 $ HsVar (mkUnqual varName
1012 (getTH_ID_SPLICE $1)))) } -- $x
1014 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
1016 -- An inst_type is what occurs in the head of an instance decl
1017 -- e.g. (Foo a, Gaz b) => Wibble a b
1018 -- It's kept as a single type, with a MonoDictTy at the right
1019 -- hand corner, for convenience.
1020 inst_type :: { LHsType RdrName }
1021 : sigtype {% checkInstType $1 }
1023 inst_types1 :: { [LHsType RdrName] }
1024 : inst_type { [$1] }
1025 | inst_type ',' inst_types1 { $1 : $3 }
1027 comma_types0 :: { [LHsType RdrName] }
1028 : comma_types1 { $1 }
1029 | {- empty -} { [] }
1031 comma_types1 :: { [LHsType RdrName] }
1033 | ctype ',' comma_types1 { $1 : $3 }
1035 tv_bndrs :: { [LHsTyVarBndr RdrName] }
1036 : tv_bndr tv_bndrs { $1 : $2 }
1037 | {- empty -} { [] }
1039 tv_bndr :: { LHsTyVarBndr RdrName }
1040 : tyvar { L1 (UserTyVar (unLoc $1)) }
1041 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2)
1044 fds :: { Located [Located (FunDep RdrName)] }
1045 : {- empty -} { noLoc [] }
1046 | '|' fds1 { LL (reverse (unLoc $2)) }
1048 fds1 :: { Located [Located (FunDep RdrName)] }
1049 : fds1 ',' fd { LL ($3 : unLoc $1) }
1052 fd :: { Located (FunDep RdrName) }
1053 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
1054 (reverse (unLoc $1), reverse (unLoc $3)) }
1056 varids0 :: { Located [RdrName] }
1057 : {- empty -} { noLoc [] }
1058 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
1060 -----------------------------------------------------------------------------
1063 kind :: { Located Kind }
1065 | akind '->' kind { LL (mkArrowKind (unLoc $1) (unLoc $3)) }
1067 akind :: { Located Kind }
1068 : '*' { L1 liftedTypeKind }
1069 | '!' { L1 unliftedTypeKind }
1070 | '(' kind ')' { LL (unLoc $2) }
1073 -----------------------------------------------------------------------------
1074 -- Datatype declarations
1076 gadt_constrlist :: { Located [LConDecl RdrName] }
1077 : '{' gadt_constrs '}' { LL (unLoc $2) }
1078 | vocurly gadt_constrs close { $2 }
1080 gadt_constrs :: { Located [LConDecl RdrName] }
1081 : gadt_constrs ';' gadt_constr { sL (comb2 $1 (head $3)) ($3 ++ unLoc $1) }
1082 | gadt_constrs ';' { $1 }
1083 | gadt_constr { sL (getLoc (head $1)) $1 }
1085 -- We allow the following forms:
1086 -- C :: Eq a => a -> T a
1087 -- C :: forall a. Eq a => !a -> T a
1088 -- D { x,y :: a } :: T a
1089 -- forall a. Eq a => D { x,y :: a } :: T a
1091 gadt_constr :: { [LConDecl RdrName] }
1092 : con_list '::' sigtype
1093 { map (sL (comb2 $1 $3)) (mkGadtDecl (unLoc $1) $3) }
1095 -- Deprecated syntax for GADT record declarations
1096 | oqtycon '{' fielddecls '}' '::' sigtype
1097 {% do { cd <- mkDeprecatedGadtRecordDecl (comb2 $1 $6) $1 $3 $6
1100 constrs :: { Located [LConDecl RdrName] }
1101 : {- empty; a GHC extension -} { noLoc [] }
1102 | maybe_docnext '=' constrs1 { L (comb2 $2 $3) (addConDocs (unLoc $3) $1) }
1104 constrs1 :: { Located [LConDecl RdrName] }
1105 : constrs1 maybe_docnext '|' maybe_docprev constr { LL (addConDoc $5 $2 : addConDocFirst (unLoc $1) $4) }
1106 | constr { L1 [$1] }
1108 constr :: { LConDecl RdrName }
1109 : maybe_docnext forall context '=>' constr_stuff maybe_docprev
1110 { let (con,details) = unLoc $5 in
1111 addConDoc (L (comb4 $2 $3 $4 $5) (mkSimpleConDecl con (unLoc $2) $3 details))
1113 | maybe_docnext forall constr_stuff maybe_docprev
1114 { let (con,details) = unLoc $3 in
1115 addConDoc (L (comb2 $2 $3) (mkSimpleConDecl con (unLoc $2) (noLoc []) details))
1118 forall :: { Located [LHsTyVarBndr RdrName] }
1119 : 'forall' tv_bndrs '.' { LL $2 }
1120 | {- empty -} { noLoc [] }
1122 constr_stuff :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1123 -- We parse the constructor declaration
1125 -- as a btype (treating C as a type constructor) and then convert C to be
1126 -- a data constructor. Reason: it might continue like this:
1128 -- in which case C really would be a type constructor. We can't resolve this
1129 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
1130 : btype {% splitCon $1 >>= return.LL }
1131 | btype conop btype { LL ($2, InfixCon $1 $3) }
1133 fielddecls :: { [ConDeclField RdrName] }
1134 : {- empty -} { [] }
1135 | fielddecls1 { $1 }
1137 fielddecls1 :: { [ConDeclField RdrName] }
1138 : fielddecl maybe_docnext ',' maybe_docprev fielddecls1
1139 { [ addFieldDoc f $4 | f <- $1 ] ++ addFieldDocs $5 $2 }
1140 -- This adds the doc $4 to each field separately
1143 fielddecl :: { [ConDeclField RdrName] } -- A list because of f,g :: Int
1144 : maybe_docnext sig_vars '::' ctype maybe_docprev { [ ConDeclField fld $4 ($1 `mplus` $5)
1145 | fld <- reverse (unLoc $2) ] }
1147 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
1148 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
1149 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
1150 -- We don't allow a context, but that's sorted out by the type checker.
1151 deriving :: { Located (Maybe [LHsType RdrName]) }
1152 : {- empty -} { noLoc Nothing }
1153 | 'deriving' qtycon {% do { let { L loc tv = $2 }
1154 ; p <- checkInstType (L loc (HsTyVar tv))
1155 ; return (LL (Just [p])) } }
1156 | 'deriving' '(' ')' { LL (Just []) }
1157 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
1158 -- Glasgow extension: allow partial
1159 -- applications in derivings
1161 -----------------------------------------------------------------------------
1162 -- Value definitions
1164 {- There's an awkward overlap with a type signature. Consider
1165 f :: Int -> Int = ...rhs...
1166 Then we can't tell whether it's a type signature or a value
1167 definition with a result signature until we see the '='.
1168 So we have to inline enough to postpone reductions until we know.
1172 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
1173 instead of qvar, we get another shift/reduce-conflict. Consider the
1176 { (^^) :: Int->Int ; } Type signature; only var allowed
1178 { (^^) :: Int->Int = ... ; } Value defn with result signature;
1179 qvar allowed (because of instance decls)
1181 We can't tell whether to reduce var to qvar until after we've read the signatures.
1184 docdecl :: { LHsDecl RdrName }
1185 : docdecld { L1 (DocD (unLoc $1)) }
1187 docdecld :: { LDocDecl RdrName }
1188 : docnext { L1 (DocCommentNext (unLoc $1)) }
1189 | docprev { L1 (DocCommentPrev (unLoc $1)) }
1190 | docnamed { L1 (case (unLoc $1) of (n, doc) -> DocCommentNamed n doc) }
1191 | docsection { L1 (case (unLoc $1) of (n, doc) -> DocGroup n doc) }
1193 decl :: { Located (OrdList (LHsDecl RdrName)) }
1195 | '!' aexp rhs {% do { pat <- checkPattern $2;
1196 return (LL $ unitOL $ LL $ ValD (
1197 PatBind (LL $ BangPat pat) (unLoc $3)
1198 placeHolderType placeHolderNames)) } }
1199 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
1200 let { l = comb2 $1 $> };
1201 return $! (sL l (unitOL $! (sL l $ ValD r))) } }
1202 | docdecl { LL $ unitOL $1 }
1204 rhs :: { Located (GRHSs RdrName) }
1205 : '=' exp wherebinds { sL (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
1206 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
1208 gdrhs :: { Located [LGRHS RdrName] }
1209 : gdrhs gdrh { LL ($2 : unLoc $1) }
1212 gdrh :: { LGRHS RdrName }
1213 : '|' guardquals '=' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1215 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
1216 : infixexp '::' sigtypedoc
1217 {% do s <- checkValSig $1 $3;
1218 return (LL $ unitOL (LL $ SigD s)) }
1219 -- See the above notes for why we need infixexp here
1220 | var ',' sig_vars '::' sigtypedoc
1221 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
1222 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
1224 | '{-# INLINE' activation qvar '#-}'
1225 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 FunLike (getINLINE $1)))) }
1226 | '{-# INLINE_CONLIKE' activation qvar '#-}'
1227 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 ConLike (getINLINE_CONLIKE $1)))) }
1228 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1229 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1231 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1232 { LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 FunLike (getSPEC_INLINE $1)))
1234 | '{-# SPECIALISE' 'instance' inst_type '#-}'
1235 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1237 -----------------------------------------------------------------------------
1240 exp :: { LHsExpr RdrName }
1241 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1242 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1243 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1244 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1245 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1248 infixexp :: { LHsExpr RdrName }
1250 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1252 exp10 :: { LHsExpr RdrName }
1253 : '\\' apat apats opt_asig '->' exp
1254 { LL $ HsLam (mkMatchGroup [LL $ Match ($2:$3) $4
1257 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1258 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1259 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1260 | '-' fexp { LL $ NegApp $2 noSyntaxExpr }
1262 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1263 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1264 return (L loc (mkHsDo DoExpr stmts body)) }
1265 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1266 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1267 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1268 | scc_annot exp { LL $ if opt_SccProfilingOn
1269 then HsSCC (unLoc $1) $2
1271 | hpc_annot exp { LL $ if opt_Hpc
1272 then HsTickPragma (unLoc $1) $2
1275 | 'proc' aexp '->' exp
1276 {% checkPattern $2 >>= \ p ->
1277 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1278 placeHolderType undefined)) }
1279 -- TODO: is LL right here?
1281 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1282 -- hdaume: core annotation
1285 scc_annot :: { Located FastString }
1286 : '_scc_' STRING {% (addWarning Opt_WarnWarningsDeprecations (getLoc $1) (text "_scc_ is deprecated; use an SCC pragma instead")) >>= \_ ->
1287 ( do scc <- getSCC $2; return $ LL scc ) }
1288 | '{-# SCC' STRING '#-}' {% do scc <- getSCC $2; return $ LL scc }
1290 hpc_annot :: { Located (FastString,(Int,Int),(Int,Int)) }
1291 : '{-# GENERATED' STRING INTEGER ':' INTEGER '-' INTEGER ':' INTEGER '#-}'
1292 { LL $ (getSTRING $2
1293 ,( fromInteger $ getINTEGER $3
1294 , fromInteger $ getINTEGER $5
1296 ,( fromInteger $ getINTEGER $7
1297 , fromInteger $ getINTEGER $9
1302 fexp :: { LHsExpr RdrName }
1303 : fexp aexp { LL $ HsApp $1 $2 }
1306 aexp :: { LHsExpr RdrName }
1307 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1308 | '~' aexp { LL $ ELazyPat $2 }
1311 aexp1 :: { LHsExpr RdrName }
1312 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4) $3
1316 -- Here was the syntax for type applications that I was planning
1317 -- but there are difficulties (e.g. what order for type args)
1318 -- so it's not enabled yet.
1319 -- But this case *is* used for the left hand side of a generic definition,
1320 -- which is parsed as an expression before being munged into a pattern
1321 | qcname '{|' type '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1322 (sL (getLoc $3) (HsType $3)) }
1324 aexp2 :: { LHsExpr RdrName }
1325 : ipvar { L1 (HsIPVar $! unLoc $1) }
1326 | qcname { L1 (HsVar $! unLoc $1) }
1327 | literal { L1 (HsLit $! unLoc $1) }
1328 -- This will enable overloaded strings permanently. Normally the renamer turns HsString
1329 -- into HsOverLit when -foverloaded-strings is on.
1330 -- | STRING { sL (getLoc $1) (HsOverLit $! mkHsIsString (getSTRING $1) placeHolderType) }
1331 | INTEGER { sL (getLoc $1) (HsOverLit $! mkHsIntegral (getINTEGER $1) placeHolderType) }
1332 | RATIONAL { sL (getLoc $1) (HsOverLit $! mkHsFractional (getRATIONAL $1) placeHolderType) }
1334 -- N.B.: sections get parsed by these next two productions.
1335 -- This allows you to write, e.g., '(+ 3, 4 -)', which isn't correct Haskell98
1336 -- (you'd have to write '((+ 3), (4 -))')
1337 -- but the less cluttered version fell out of having texps.
1338 | '(' texp ')' { LL (HsPar $2) }
1339 | '(' tup_exprs ')' { LL (ExplicitTuple $2 Boxed) }
1341 | '(#' texp '#)' { LL (ExplicitTuple [Present $2] Unboxed) }
1342 | '(#' tup_exprs '#)' { LL (ExplicitTuple $2 Unboxed) }
1344 | '[' list ']' { LL (unLoc $2) }
1345 | '[:' parr ':]' { LL (unLoc $2) }
1346 | '_' { L1 EWildPat }
1348 -- Template Haskell Extension
1349 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1350 (L1 $ HsVar (mkUnqual varName
1351 (getTH_ID_SPLICE $1)))) } -- $x
1352 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1354 | TH_QUASIQUOTE { let { loc = getLoc $1
1355 ; ITquasiQuote (quoter, quote, quoteSpan) = unLoc $1
1356 ; quoterId = mkUnqual varName quoter
1358 in sL loc $ HsQuasiQuoteE (mkHsQuasiQuote quoterId quoteSpan quote) }
1359 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1360 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1361 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1362 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1363 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1364 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1365 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1366 return (LL $ HsBracket (PatBr p)) }
1367 | '[d|' cvtopbody '|]' {% checkDecBrGroup $2 >>= \g ->
1368 return (LL $ HsBracket (DecBr g)) }
1370 -- arrow notation extension
1371 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1373 cmdargs :: { [LHsCmdTop RdrName] }
1374 : cmdargs acmd { $2 : $1 }
1375 | {- empty -} { [] }
1377 acmd :: { LHsCmdTop RdrName }
1378 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1380 cvtopbody :: { [LHsDecl RdrName] }
1381 : '{' cvtopdecls0 '}' { $2 }
1382 | vocurly cvtopdecls0 close { $2 }
1384 cvtopdecls0 :: { [LHsDecl RdrName] }
1385 : {- empty -} { [] }
1388 -----------------------------------------------------------------------------
1389 -- Tuple expressions
1391 -- "texp" is short for tuple expressions:
1392 -- things that can appear unparenthesized as long as they're
1393 -- inside parens or delimitted by commas
1394 texp :: { LHsExpr RdrName }
1397 -- Note [Parsing sections]
1398 -- ~~~~~~~~~~~~~~~~~~~~~~~
1399 -- We include left and right sections here, which isn't
1400 -- technically right according to Haskell 98. For example
1401 -- (3 +, True) isn't legal
1402 -- However, we want to parse bang patterns like
1404 -- and it's convenient to do so here as a section
1405 -- Then when converting expr to pattern we unravel it again
1406 -- Meanwhile, the renamer checks that real sections appear
1408 | infixexp qop { LL $ SectionL $1 $2 }
1409 | qopm infixexp { LL $ SectionR $1 $2 }
1411 -- View patterns get parenthesized above
1412 | exp '->' exp { LL $ EViewPat $1 $3 }
1414 -- Always at least one comma
1415 tup_exprs :: { [HsTupArg RdrName] }
1416 : texp commas_tup_tail { Present $1 : $2 }
1417 | commas tup_tail { replicate $1 missingTupArg ++ $2 }
1419 -- Always starts with commas; always follows an expr
1420 commas_tup_tail :: { [HsTupArg RdrName] }
1421 commas_tup_tail : commas tup_tail { replicate ($1-1) missingTupArg ++ $2 }
1423 -- Always follows a comma
1424 tup_tail :: { [HsTupArg RdrName] }
1425 : texp commas_tup_tail { Present $1 : $2 }
1426 | texp { [Present $1] }
1427 | {- empty -} { [missingTupArg] }
1429 -----------------------------------------------------------------------------
1432 -- The rules below are little bit contorted to keep lexps left-recursive while
1433 -- avoiding another shift/reduce-conflict.
1435 list :: { LHsExpr RdrName }
1436 : texp { L1 $ ExplicitList placeHolderType [$1] }
1437 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1438 | texp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1439 | texp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1440 | texp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1441 | texp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1442 | texp '|' flattenedpquals { sL (comb2 $1 $>) $ mkHsDo ListComp (unLoc $3) $1 }
1444 lexps :: { Located [LHsExpr RdrName] }
1445 : lexps ',' texp { LL (((:) $! $3) $! unLoc $1) }
1446 | texp ',' texp { LL [$3,$1] }
1448 -----------------------------------------------------------------------------
1449 -- List Comprehensions
1451 flattenedpquals :: { Located [LStmt RdrName] }
1452 : pquals { case (unLoc $1) of
1453 ParStmt [(qs, _)] -> L1 qs
1454 -- We just had one thing in our "parallel" list so
1455 -- we simply return that thing directly
1458 -- We actually found some actual parallel lists so
1459 -- we leave them into as a ParStmt
1462 pquals :: { LStmt RdrName }
1463 : pquals1 { L1 (ParStmt [(qs, undefined) | qs <- (reverse (unLoc $1))]) }
1465 pquals1 :: { Located [[LStmt RdrName]] }
1466 : pquals1 '|' squals { LL (unLoc $3 : unLoc $1) }
1467 | squals { L (getLoc $1) [unLoc $1] }
1469 squals :: { Located [LStmt RdrName] }
1470 : squals1 { L (getLoc $1) (reverse (unLoc $1)) }
1472 squals1 :: { Located [LStmt RdrName] }
1473 : transformquals1 { LL (unLoc $1) }
1475 transformquals1 :: { Located [LStmt RdrName] }
1476 : transformquals1 ',' transformqual { LL $ [LL ((unLoc $3) (unLoc $1))] }
1477 | transformquals1 ',' qual { LL ($3 : unLoc $1) }
1478 -- | transformquals1 ',' '{|' pquals '|}' { LL ($4 : unLoc $1) }
1479 | transformqual { LL $ [LL ((unLoc $1) [])] }
1481 -- | '{|' pquals '|}' { L1 [$2] }
1484 -- It is possible to enable bracketing (associating) qualifier lists by uncommenting the lines with {| |}
1485 -- above. Due to a lack of consensus on the syntax, this feature is not being used until we get user
1486 -- demand. Note that the {| |} symbols are reused from -XGenerics and hence if you want to compile
1487 -- a program that makes use of this temporary syntax you must supply that flag to GHC
1489 transformqual :: { Located ([LStmt RdrName] -> Stmt RdrName) }
1490 : 'then' exp { LL $ \leftStmts -> (mkTransformStmt (reverse leftStmts) $2) }
1492 | 'then' exp 'by' exp { LL $ \leftStmts -> (mkTransformByStmt (reverse leftStmts) $2 $4) }
1493 | 'then' 'group' 'by' exp { LL $ \leftStmts -> (mkGroupByStmt (reverse leftStmts) $4) }
1495 -- These two productions deliberately have a shift-reduce conflict. I have made 'group' into a special_id,
1496 -- which means you can enable TransformListComp while still using Data.List.group. However, this makes the two
1497 -- productions ambiguous. I've set things up so that Happy chooses to resolve the conflict in that case by
1498 -- choosing the "group by" variant, which is what we want.
1500 -- This is rather dubious: the user might be confused as to how to parse this statement. However, it is a good
1501 -- practical choice. NB: Data.List.group :: [a] -> [[a]], so using the first production would not even type check
1502 -- if /that/ is the group function we conflict with.
1503 | 'then' 'group' 'using' exp { LL $ \leftStmts -> (mkGroupUsingStmt (reverse leftStmts) $4) }
1504 | 'then' 'group' 'by' exp 'using' exp { LL $ \leftStmts -> (mkGroupByUsingStmt (reverse leftStmts) $4 $6) }
1506 -----------------------------------------------------------------------------
1507 -- Parallel array expressions
1509 -- The rules below are little bit contorted; see the list case for details.
1510 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1511 -- Moreover, we allow explicit arrays with no element (represented by the nil
1512 -- constructor in the list case).
1514 parr :: { LHsExpr RdrName }
1515 : { noLoc (ExplicitPArr placeHolderType []) }
1516 | texp { L1 $ ExplicitPArr placeHolderType [$1] }
1517 | lexps { L1 $ ExplicitPArr placeHolderType
1518 (reverse (unLoc $1)) }
1519 | texp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1520 | texp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1521 | texp '|' flattenedpquals { LL $ mkHsDo PArrComp (unLoc $3) $1 }
1523 -- We are reusing `lexps' and `flattenedpquals' from the list case.
1525 -----------------------------------------------------------------------------
1528 guardquals :: { Located [LStmt RdrName] }
1529 : guardquals1 { L (getLoc $1) (reverse (unLoc $1)) }
1531 guardquals1 :: { Located [LStmt RdrName] }
1532 : guardquals1 ',' qual { LL ($3 : unLoc $1) }
1535 -----------------------------------------------------------------------------
1536 -- Case alternatives
1538 altslist :: { Located [LMatch RdrName] }
1539 : '{' alts '}' { LL (reverse (unLoc $2)) }
1540 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1542 alts :: { Located [LMatch RdrName] }
1543 : alts1 { L1 (unLoc $1) }
1544 | ';' alts { LL (unLoc $2) }
1546 alts1 :: { Located [LMatch RdrName] }
1547 : alts1 ';' alt { LL ($3 : unLoc $1) }
1548 | alts1 ';' { LL (unLoc $1) }
1551 alt :: { LMatch RdrName }
1552 : pat opt_sig alt_rhs { LL (Match [$1] $2 (unLoc $3)) }
1554 alt_rhs :: { Located (GRHSs RdrName) }
1555 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1557 ralt :: { Located [LGRHS RdrName] }
1558 : '->' exp { LL (unguardedRHS $2) }
1559 | gdpats { L1 (reverse (unLoc $1)) }
1561 gdpats :: { Located [LGRHS RdrName] }
1562 : gdpats gdpat { LL ($2 : unLoc $1) }
1565 gdpat :: { LGRHS RdrName }
1566 : '|' guardquals '->' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1568 -- 'pat' recognises a pattern, including one with a bang at the top
1569 -- e.g. "!x" or "!(x,y)" or "C a b" etc
1570 -- Bangs inside are parsed as infix operator applications, so that
1571 -- we parse them right when bang-patterns are off
1572 pat :: { LPat RdrName }
1573 pat : exp {% checkPattern $1 }
1574 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1576 apat :: { LPat RdrName }
1577 apat : aexp {% checkPattern $1 }
1578 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1580 apats :: { [LPat RdrName] }
1581 : apat apats { $1 : $2 }
1582 | {- empty -} { [] }
1584 -----------------------------------------------------------------------------
1585 -- Statement sequences
1587 stmtlist :: { Located [LStmt RdrName] }
1588 : '{' stmts '}' { LL (unLoc $2) }
1589 | vocurly stmts close { $2 }
1591 -- do { ;; s ; s ; ; s ;; }
1592 -- The last Stmt should be an expression, but that's hard to enforce
1593 -- here, because we need too much lookahead if we see do { e ; }
1594 -- So we use ExprStmts throughout, and switch the last one over
1595 -- in ParseUtils.checkDo instead
1596 stmts :: { Located [LStmt RdrName] }
1597 : stmt stmts_help { LL ($1 : unLoc $2) }
1598 | ';' stmts { LL (unLoc $2) }
1599 | {- empty -} { noLoc [] }
1601 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1602 : ';' stmts { LL (unLoc $2) }
1603 | {- empty -} { noLoc [] }
1605 -- For typing stmts at the GHCi prompt, where
1606 -- the input may consist of just comments.
1607 maybe_stmt :: { Maybe (LStmt RdrName) }
1609 | {- nothing -} { Nothing }
1611 stmt :: { LStmt RdrName }
1613 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1615 qual :: { LStmt RdrName }
1616 : pat '<-' exp { LL $ mkBindStmt $1 $3 }
1617 | exp { L1 $ mkExprStmt $1 }
1618 | 'let' binds { LL $ LetStmt (unLoc $2) }
1620 -----------------------------------------------------------------------------
1621 -- Record Field Update/Construction
1623 fbinds :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1625 | {- empty -} { ([], False) }
1627 fbinds1 :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1628 : fbind ',' fbinds1 { case $3 of (flds, dd) -> ($1 : flds, dd) }
1629 | fbind { ([$1], False) }
1630 | '..' { ([], True) }
1632 fbind :: { HsRecField RdrName (LHsExpr RdrName) }
1633 : qvar '=' exp { HsRecField $1 $3 False }
1634 | qvar { HsRecField $1 (L (getLoc $1) (HsVar (unLoc $1))) True }
1635 -- Here's where we say that plain 'x'
1636 -- means exactly 'x = x'. The pun-flag boolean is
1637 -- there so we can still print it right
1639 -----------------------------------------------------------------------------
1640 -- Implicit Parameter Bindings
1642 dbinds :: { Located [LIPBind RdrName] }
1643 : dbinds ';' dbind { let { this = $3; rest = unLoc $1 }
1644 in rest `seq` this `seq` LL (this : rest) }
1645 | dbinds ';' { LL (unLoc $1) }
1646 | dbind { let this = $1 in this `seq` L1 [this] }
1647 -- | {- empty -} { [] }
1649 dbind :: { LIPBind RdrName }
1650 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1652 ipvar :: { Located (IPName RdrName) }
1653 : IPDUPVARID { L1 (IPName (mkUnqual varName (getIPDUPVARID $1))) }
1655 -----------------------------------------------------------------------------
1656 -- Warnings and deprecations
1658 namelist :: { Located [RdrName] }
1659 namelist : name_var { L1 [unLoc $1] }
1660 | name_var ',' namelist { LL (unLoc $1 : unLoc $3) }
1662 name_var :: { Located RdrName }
1663 name_var : var { $1 }
1666 -----------------------------------------
1667 -- Data constructors
1668 qcon :: { Located RdrName }
1670 | '(' qconsym ')' { LL (unLoc $2) }
1671 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1672 -- The case of '[:' ':]' is part of the production `parr'
1674 con :: { Located RdrName }
1676 | '(' consym ')' { LL (unLoc $2) }
1677 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1679 con_list :: { Located [Located RdrName] }
1680 con_list : con { L1 [$1] }
1681 | con ',' con_list { LL ($1 : unLoc $3) }
1683 sysdcon :: { Located DataCon } -- Wired in data constructors
1684 : '(' ')' { LL unitDataCon }
1685 | '(' commas ')' { LL $ tupleCon Boxed ($2 + 1) }
1686 | '(#' '#)' { LL $ unboxedSingletonDataCon }
1687 | '(#' commas '#)' { LL $ tupleCon Unboxed ($2 + 1) }
1688 | '[' ']' { LL nilDataCon }
1690 conop :: { Located RdrName }
1692 | '`' conid '`' { LL (unLoc $2) }
1694 qconop :: { Located RdrName }
1696 | '`' qconid '`' { LL (unLoc $2) }
1698 -----------------------------------------------------------------------------
1699 -- Type constructors
1701 gtycon :: { Located RdrName } -- A "general" qualified tycon
1703 | '(' ')' { LL $ getRdrName unitTyCon }
1704 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed ($2 + 1)) }
1705 | '(#' '#)' { LL $ getRdrName unboxedSingletonTyCon }
1706 | '(#' commas '#)' { LL $ getRdrName (tupleTyCon Unboxed ($2 + 1)) }
1707 | '(' '->' ')' { LL $ getRdrName funTyCon }
1708 | '[' ']' { LL $ listTyCon_RDR }
1709 | '[:' ':]' { LL $ parrTyCon_RDR }
1711 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1713 | '(' qtyconsym ')' { LL (unLoc $2) }
1715 qtyconop :: { Located RdrName } -- Qualified or unqualified
1717 | '`' qtycon '`' { LL (unLoc $2) }
1719 qtycon :: { Located RdrName } -- Qualified or unqualified
1720 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1721 | PREFIXQCONSYM { L1 $! mkQual tcClsName (getPREFIXQCONSYM $1) }
1724 tycon :: { Located RdrName } -- Unqualified
1725 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1727 qtyconsym :: { Located RdrName }
1728 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1731 tyconsym :: { Located RdrName }
1732 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1734 -----------------------------------------------------------------------------
1737 op :: { Located RdrName } -- used in infix decls
1741 varop :: { Located RdrName }
1743 | '`' varid '`' { LL (unLoc $2) }
1745 qop :: { LHsExpr RdrName } -- used in sections
1746 : qvarop { L1 $ HsVar (unLoc $1) }
1747 | qconop { L1 $ HsVar (unLoc $1) }
1749 qopm :: { LHsExpr RdrName } -- used in sections
1750 : qvaropm { L1 $ HsVar (unLoc $1) }
1751 | qconop { L1 $ HsVar (unLoc $1) }
1753 qvarop :: { Located RdrName }
1755 | '`' qvarid '`' { LL (unLoc $2) }
1757 qvaropm :: { Located RdrName }
1758 : qvarsym_no_minus { $1 }
1759 | '`' qvarid '`' { LL (unLoc $2) }
1761 -----------------------------------------------------------------------------
1764 tyvar :: { Located RdrName }
1765 tyvar : tyvarid { $1 }
1766 | '(' tyvarsym ')' { LL (unLoc $2) }
1768 tyvarop :: { Located RdrName }
1769 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1771 | '.' {% parseErrorSDoc (getLoc $1)
1772 (vcat [ptext (sLit "Illegal symbol '.' in type"),
1773 ptext (sLit "Perhaps you intended -XRankNTypes or similar flag"),
1774 ptext (sLit "to enable explicit-forall syntax: forall <tvs>. <type>")])
1777 tyvarid :: { Located RdrName }
1778 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1779 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1780 | 'unsafe' { L1 $! mkUnqual tvName (fsLit "unsafe") }
1781 | 'safe' { L1 $! mkUnqual tvName (fsLit "safe") }
1782 | 'threadsafe' { L1 $! mkUnqual tvName (fsLit "threadsafe") }
1784 tyvarsym :: { Located RdrName }
1785 -- Does not include "!", because that is used for strictness marks
1786 -- or ".", because that separates the quantified type vars from the rest
1787 -- or "*", because that's used for kinds
1788 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1790 -----------------------------------------------------------------------------
1793 var :: { Located RdrName }
1795 | '(' varsym ')' { LL (unLoc $2) }
1797 qvar :: { Located RdrName }
1799 | '(' varsym ')' { LL (unLoc $2) }
1800 | '(' qvarsym1 ')' { LL (unLoc $2) }
1801 -- We've inlined qvarsym here so that the decision about
1802 -- whether it's a qvar or a var can be postponed until
1803 -- *after* we see the close paren.
1805 qvarid :: { Located RdrName }
1807 | QVARID { L1 $! mkQual varName (getQVARID $1) }
1808 | PREFIXQVARSYM { L1 $! mkQual varName (getPREFIXQVARSYM $1) }
1810 varid :: { Located RdrName }
1811 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1812 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1813 | 'unsafe' { L1 $! mkUnqual varName (fsLit "unsafe") }
1814 | 'safe' { L1 $! mkUnqual varName (fsLit "safe") }
1815 | 'threadsafe' { L1 $! mkUnqual varName (fsLit "threadsafe") }
1816 | 'forall' { L1 $! mkUnqual varName (fsLit "forall") }
1817 | 'family' { L1 $! mkUnqual varName (fsLit "family") }
1819 qvarsym :: { Located RdrName }
1823 qvarsym_no_minus :: { Located RdrName }
1824 : varsym_no_minus { $1 }
1827 qvarsym1 :: { Located RdrName }
1828 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1830 varsym :: { Located RdrName }
1831 : varsym_no_minus { $1 }
1832 | '-' { L1 $ mkUnqual varName (fsLit "-") }
1834 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1835 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1836 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1839 -- These special_ids are treated as keywords in various places,
1840 -- but as ordinary ids elsewhere. 'special_id' collects all these
1841 -- except 'unsafe', 'forall', and 'family' whose treatment differs
1842 -- depending on context
1843 special_id :: { Located FastString }
1845 : 'as' { L1 (fsLit "as") }
1846 | 'qualified' { L1 (fsLit "qualified") }
1847 | 'hiding' { L1 (fsLit "hiding") }
1848 | 'export' { L1 (fsLit "export") }
1849 | 'label' { L1 (fsLit "label") }
1850 | 'dynamic' { L1 (fsLit "dynamic") }
1851 | 'stdcall' { L1 (fsLit "stdcall") }
1852 | 'ccall' { L1 (fsLit "ccall") }
1853 | 'prim' { L1 (fsLit "prim") }
1854 | 'group' { L1 (fsLit "group") }
1856 special_sym :: { Located FastString }
1857 special_sym : '!' { L1 (fsLit "!") }
1858 | '.' { L1 (fsLit ".") }
1859 | '*' { L1 (fsLit "*") }
1861 -----------------------------------------------------------------------------
1862 -- Data constructors
1864 qconid :: { Located RdrName } -- Qualified or unqualified
1866 | QCONID { L1 $! mkQual dataName (getQCONID $1) }
1867 | PREFIXQCONSYM { L1 $! mkQual dataName (getPREFIXQCONSYM $1) }
1869 conid :: { Located RdrName }
1870 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1872 qconsym :: { Located RdrName } -- Qualified or unqualified
1874 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1876 consym :: { Located RdrName }
1877 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1879 -- ':' means only list cons
1880 | ':' { L1 $ consDataCon_RDR }
1883 -----------------------------------------------------------------------------
1886 literal :: { Located HsLit }
1887 : CHAR { L1 $ HsChar $ getCHAR $1 }
1888 | STRING { L1 $ HsString $ getSTRING $1 }
1889 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1890 | PRIMWORD { L1 $ HsWordPrim $ getPRIMWORD $1 }
1891 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1892 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1893 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1894 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1896 -----------------------------------------------------------------------------
1900 : vccurly { () } -- context popped in lexer.
1901 | error {% popContext }
1903 -----------------------------------------------------------------------------
1904 -- Miscellaneous (mostly renamings)
1906 modid :: { Located ModuleName }
1907 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1908 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1911 (unpackFS mod ++ '.':unpackFS c))
1915 : commas ',' { $1 + 1 }
1918 -----------------------------------------------------------------------------
1919 -- Documentation comments
1921 docnext :: { LHsDoc RdrName }
1922 : DOCNEXT {% case parseHaddockParagraphs (tokenise (getDOCNEXT $1)) of {
1923 MyLeft err -> parseError (getLoc $1) err;
1924 MyRight doc -> return (L1 doc) } }
1926 docprev :: { LHsDoc RdrName }
1927 : DOCPREV {% case parseHaddockParagraphs (tokenise (getDOCPREV $1)) of {
1928 MyLeft err -> parseError (getLoc $1) err;
1929 MyRight doc -> return (L1 doc) } }
1931 docnamed :: { Located (String, (HsDoc RdrName)) }
1933 let string = getDOCNAMED $1
1934 (name, rest) = break isSpace string
1935 in case parseHaddockParagraphs (tokenise rest) of {
1936 MyLeft err -> parseError (getLoc $1) err;
1937 MyRight doc -> return (L1 (name, doc)) } }
1939 docsection :: { Located (Int, HsDoc RdrName) }
1940 : DOCSECTION {% let (n, doc) = getDOCSECTION $1 in
1941 case parseHaddockString (tokenise doc) of {
1942 MyLeft err -> parseError (getLoc $1) err;
1943 MyRight doc -> return (L1 (n, doc)) } }
1945 moduleheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
1946 : DOCNEXT {% let string = getDOCNEXT $1 in
1947 case parseModuleHeader string of {
1948 Right (str, info) ->
1949 case parseHaddockParagraphs (tokenise str) of {
1950 MyLeft err -> parseError (getLoc $1) err;
1951 MyRight doc -> return (info, Just doc);
1953 Left err -> parseError (getLoc $1) err
1956 maybe_docprev :: { Maybe (LHsDoc RdrName) }
1957 : docprev { Just $1 }
1958 | {- empty -} { Nothing }
1960 maybe_docnext :: { Maybe (LHsDoc RdrName) }
1961 : docnext { Just $1 }
1962 | {- empty -} { Nothing }
1966 happyError = srcParseFail
1968 getVARID (L _ (ITvarid x)) = x
1969 getCONID (L _ (ITconid x)) = x
1970 getVARSYM (L _ (ITvarsym x)) = x
1971 getCONSYM (L _ (ITconsym x)) = x
1972 getQVARID (L _ (ITqvarid x)) = x
1973 getQCONID (L _ (ITqconid x)) = x
1974 getQVARSYM (L _ (ITqvarsym x)) = x
1975 getQCONSYM (L _ (ITqconsym x)) = x
1976 getPREFIXQVARSYM (L _ (ITprefixqvarsym x)) = x
1977 getPREFIXQCONSYM (L _ (ITprefixqconsym x)) = x
1978 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1979 getCHAR (L _ (ITchar x)) = x
1980 getSTRING (L _ (ITstring x)) = x
1981 getINTEGER (L _ (ITinteger x)) = x
1982 getRATIONAL (L _ (ITrational x)) = x
1983 getPRIMCHAR (L _ (ITprimchar x)) = x
1984 getPRIMSTRING (L _ (ITprimstring x)) = x
1985 getPRIMINTEGER (L _ (ITprimint x)) = x
1986 getPRIMWORD (L _ (ITprimword x)) = x
1987 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1988 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1989 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1990 getINLINE (L _ (ITinline_prag b)) = b
1991 getINLINE_CONLIKE (L _ (ITinline_conlike_prag b)) = b
1992 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
1994 getDOCNEXT (L _ (ITdocCommentNext x)) = x
1995 getDOCPREV (L _ (ITdocCommentPrev x)) = x
1996 getDOCNAMED (L _ (ITdocCommentNamed x)) = x
1997 getDOCSECTION (L _ (ITdocSection n x)) = (n, x)
1999 getSCC :: Located Token -> P FastString
2000 getSCC lt = do let s = getSTRING lt
2001 err = "Spaces are not allowed in SCCs"
2002 -- We probably actually want to be more restrictive than this
2003 if ' ' `elem` unpackFS s
2004 then failSpanMsgP (getLoc lt) (text err)
2007 -- Utilities for combining source spans
2008 comb2 :: Located a -> Located b -> SrcSpan
2009 comb2 a b = a `seq` b `seq` combineLocs a b
2011 comb3 :: Located a -> Located b -> Located c -> SrcSpan
2012 comb3 a b c = a `seq` b `seq` c `seq`
2013 combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
2015 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
2016 comb4 a b c d = a `seq` b `seq` c `seq` d `seq`
2017 (combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
2018 combineSrcSpans (getLoc c) (getLoc d))
2020 -- strict constructor version:
2022 sL :: SrcSpan -> a -> Located a
2023 sL span a = span `seq` a `seq` L span a
2025 -- Make a source location for the file. We're a bit lazy here and just
2026 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
2027 -- try to find the span of the whole file (ToDo).
2028 fileSrcSpan :: P SrcSpan
2031 let loc = mkSrcLoc (srcLocFile l) 1 0;
2032 return (mkSrcSpan loc loc)