2 -- ---------------------------------------------------------------------------
3 -- (c) The University of Glasgow 1997-2003
7 -- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
8 -- ---------------------------------------------------------------------------
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 module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
21 #define INCLUDE #include
22 INCLUDE "HsVersions.h"
26 import HscTypes ( IsBootInterface, DeprecTxt )
29 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
30 unboxedSingletonTyCon, unboxedSingletonDataCon,
31 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
32 import Type ( funTyCon )
33 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
34 CCallConv(..), CCallTarget(..), defaultCCallConv
36 import OccName ( varName, dataName, tcClsName, tvName )
37 import DataCon ( DataCon, dataConName )
38 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
39 SrcSpan, combineLocs, srcLocFile,
42 import StaticFlags ( opt_SccProfilingOn, opt_Hpc )
43 import Type ( Kind, mkArrowKind, liftedTypeKind, unliftedTypeKind )
44 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
45 Activation(..), defaultInlineSpec )
49 import {-# SOURCE #-} HaddockLex hiding ( Token )
53 import Maybes ( orElse )
56 import Control.Monad ( unless )
59 import Control.Monad ( mplus )
63 -----------------------------------------------------------------------------
66 Conflicts: 33 shift/reduce
69 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
70 would think the two should never occur in the same context.
74 -----------------------------------------------------------------------------
77 Conflicts: 34 shift/reduce
80 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
81 would think the two should never occur in the same context.
85 -----------------------------------------------------------------------------
88 Conflicts: 32 shift/reduce
91 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
92 would think the two should never occur in the same context.
96 -----------------------------------------------------------------------------
99 Conflicts: 37 shift/reduce
102 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
103 would think the two should never occur in the same context.
107 -----------------------------------------------------------------------------
108 Conflicts: 38 shift/reduce (1.25)
110 10 for abiguity in 'if x then y else z + 1' [State 178]
111 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
112 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
114 1 for ambiguity in 'if x then y else z :: T' [State 178]
115 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
117 4 for ambiguity in 'if x then y else z -< e' [State 178]
118 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
119 There are four such operators: -<, >-, -<<, >>-
122 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
123 Which of these two is intended?
125 (x::T) -> T -- Rhs is T
128 (x::T -> T) -> .. -- Rhs is ...
130 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
133 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
134 Same duplication between states 11 and 253 as the previous case
136 1 for ambiguity in 'let ?x ...' [State 329]
137 the parser can't tell whether the ?x is the lhs of a normal binding or
138 an implicit binding. Fortunately resolving as shift gives it the only
139 sensible meaning, namely the lhs of an implicit binding.
141 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
142 we don't know whether the '[' starts the activation or not: it
143 might be the start of the declaration with the activation being
144 empty. --SDM 1/4/2002
146 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
147 since 'forall' is a valid variable name, we don't know whether
148 to treat a forall on the input as the beginning of a quantifier
149 or the beginning of the rule itself. Resolving to shift means
150 it's always treated as a quantifier, hence the above is disallowed.
151 This saves explicitly defining a grammar for the rule lhs that
152 doesn't include 'forall'.
154 1 for ambiguity when the source file starts with "-- | doc". We need another
155 token of lookahead to determine if a top declaration or the 'module' keyword
156 follows. Shift parses as if the 'module' keyword follows.
158 -- ---------------------------------------------------------------------------
159 -- Adding location info
161 This is done in a stylised way using the three macros below, L0, L1
162 and LL. Each of these macros can be thought of as having type
164 L0, L1, LL :: a -> Located a
166 They each add a SrcSpan to their argument.
168 L0 adds 'noSrcSpan', used for empty productions
169 -- This doesn't seem to work anymore -=chak
171 L1 for a production with a single token on the lhs. Grabs the SrcSpan
174 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
175 the first and last tokens.
177 These suffice for the majority of cases. However, we must be
178 especially careful with empty productions: LL won't work if the first
179 or last token on the lhs can represent an empty span. In these cases,
180 we have to calculate the span using more of the tokens from the lhs, eg.
182 | 'newtype' tycl_hdr '=' newconstr deriving
184 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
186 We provide comb3 and comb4 functions which are useful in such cases.
188 Be careful: there's no checking that you actually got this right, the
189 only symptom will be that the SrcSpans of your syntax will be
193 * We must expand these macros *before* running Happy, which is why this file is
194 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
196 #define L0 L noSrcSpan
197 #define L1 sL (getLoc $1)
198 #define LL sL (comb2 $1 $>)
200 -- -----------------------------------------------------------------------------
205 '_' { L _ ITunderscore } -- Haskell keywords
207 'case' { L _ ITcase }
208 'class' { L _ ITclass }
209 'data' { L _ ITdata }
210 'default' { L _ ITdefault }
211 'deriving' { L _ ITderiving }
213 'else' { L _ ITelse }
214 'hiding' { L _ IThiding }
216 'import' { L _ ITimport }
218 'infix' { L _ ITinfix }
219 'infixl' { L _ ITinfixl }
220 'infixr' { L _ ITinfixr }
221 'instance' { L _ ITinstance }
223 'module' { L _ ITmodule }
224 'newtype' { L _ ITnewtype }
226 'qualified' { L _ ITqualified }
227 'then' { L _ ITthen }
228 'type' { L _ ITtype }
229 'where' { L _ ITwhere }
230 '_scc_' { L _ ITscc } -- ToDo: remove
232 'forall' { L _ ITforall } -- GHC extension keywords
233 'foreign' { L _ ITforeign }
234 'export' { L _ ITexport }
235 'label' { L _ ITlabel }
236 'dynamic' { L _ ITdynamic }
237 'safe' { L _ ITsafe }
238 'threadsafe' { L _ ITthreadsafe }
239 'unsafe' { L _ ITunsafe }
241 'family' { L _ ITfamily }
242 'stdcall' { L _ ITstdcallconv }
243 'ccall' { L _ ITccallconv }
244 'dotnet' { L _ ITdotnet }
245 'proc' { L _ ITproc } -- for arrow notation extension
246 'rec' { L _ ITrec } -- for arrow notation extension
247 'group' { L _ ITgroup } -- for list transform extension
248 'by' { L _ ITby } -- for list transform extension
249 'using' { L _ ITusing } -- for list transform extension
251 '{-# INLINE' { L _ (ITinline_prag _) }
252 '{-# SPECIALISE' { L _ ITspec_prag }
253 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
254 '{-# SOURCE' { L _ ITsource_prag }
255 '{-# RULES' { L _ ITrules_prag }
256 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
257 '{-# SCC' { L _ ITscc_prag }
258 '{-# GENERATED' { L _ ITgenerated_prag }
259 '{-# DEPRECATED' { L _ ITdeprecated_prag }
260 '{-# UNPACK' { L _ ITunpack_prag }
261 '#-}' { L _ ITclose_prag }
263 '..' { L _ ITdotdot } -- reserved symbols
265 '::' { L _ ITdcolon }
269 '<-' { L _ ITlarrow }
270 '->' { L _ ITrarrow }
273 '=>' { L _ ITdarrow }
277 '-<' { L _ ITlarrowtail } -- for arrow notation
278 '>-' { L _ ITrarrowtail } -- for arrow notation
279 '-<<' { L _ ITLarrowtail } -- for arrow notation
280 '>>-' { L _ ITRarrowtail } -- for arrow notation
283 '{' { L _ ITocurly } -- special symbols
285 '{|' { L _ ITocurlybar }
286 '|}' { L _ ITccurlybar }
287 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
288 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
291 '[:' { L _ ITopabrack }
292 ':]' { L _ ITcpabrack }
295 '(#' { L _ IToubxparen }
296 '#)' { L _ ITcubxparen }
297 '(|' { L _ IToparenbar }
298 '|)' { L _ ITcparenbar }
301 '`' { L _ ITbackquote }
303 VARID { L _ (ITvarid _) } -- identifiers
304 CONID { L _ (ITconid _) }
305 VARSYM { L _ (ITvarsym _) }
306 CONSYM { L _ (ITconsym _) }
307 QVARID { L _ (ITqvarid _) }
308 QCONID { L _ (ITqconid _) }
309 QVARSYM { L _ (ITqvarsym _) }
310 QCONSYM { L _ (ITqconsym _) }
312 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
314 CHAR { L _ (ITchar _) }
315 STRING { L _ (ITstring _) }
316 INTEGER { L _ (ITinteger _) }
317 RATIONAL { L _ (ITrational _) }
319 PRIMCHAR { L _ (ITprimchar _) }
320 PRIMSTRING { L _ (ITprimstring _) }
321 PRIMINTEGER { L _ (ITprimint _) }
322 PRIMFLOAT { L _ (ITprimfloat _) }
323 PRIMDOUBLE { L _ (ITprimdouble _) }
325 DOCNEXT { L _ (ITdocCommentNext _) }
326 DOCPREV { L _ (ITdocCommentPrev _) }
327 DOCNAMED { L _ (ITdocCommentNamed _) }
328 DOCSECTION { L _ (ITdocSection _ _) }
331 '[|' { L _ ITopenExpQuote }
332 '[p|' { L _ ITopenPatQuote }
333 '[t|' { L _ ITopenTypQuote }
334 '[d|' { L _ ITopenDecQuote }
335 '|]' { L _ ITcloseQuote }
336 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
337 '$(' { L _ ITparenEscape } -- $( exp )
338 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
339 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
340 TH_QUASIQUOTE { L _ (ITquasiQuote _) }
342 %monad { P } { >>= } { return }
343 %lexer { lexer } { L _ ITeof }
344 %name parseModule module
345 %name parseStmt maybe_stmt
346 %name parseIdentifier identifier
347 %name parseType ctype
348 %partial parseHeader header
349 %tokentype { (Located Token) }
352 -----------------------------------------------------------------------------
353 -- Identifiers; one of the entry points
354 identifier :: { Located RdrName }
359 | '(' '->' ')' { LL $ getRdrName funTyCon }
361 -----------------------------------------------------------------------------
364 -- The place for module deprecation is really too restrictive, but if it
365 -- was allowed at its natural place just before 'module', we get an ugly
366 -- s/r conflict with the second alternative. Another solution would be the
367 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
368 -- either, and DEPRECATED is only expected to be used by people who really
369 -- know what they are doing. :-)
371 module :: { Located (HsModule RdrName) }
372 : maybedocheader 'module' modid maybemoddeprec maybeexports 'where' body
373 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
374 return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4
377 {% fileSrcSpan >>= \ loc ->
378 return (L loc (HsModule Nothing Nothing
379 (fst $1) (snd $1) Nothing emptyHaddockModInfo
382 maybedocheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
383 : moduleheader { (fst $1, snd $1) }
384 | {- empty -} { (emptyHaddockModInfo, Nothing) }
386 missing_module_keyword :: { () }
387 : {- empty -} {% pushCurrentContext }
389 maybemoddeprec :: { Maybe DeprecTxt }
390 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
391 | {- empty -} { Nothing }
393 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
395 | vocurly top close { $2 }
397 body2 :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
399 | missing_module_keyword top close { $2 }
401 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
402 : importdecls { (reverse $1,[]) }
403 | importdecls ';' cvtopdecls { (reverse $1,$3) }
404 | cvtopdecls { ([],$1) }
406 cvtopdecls :: { [LHsDecl RdrName] }
407 : topdecls { cvTopDecls $1 }
409 -----------------------------------------------------------------------------
410 -- Module declaration & imports only
412 header :: { Located (HsModule RdrName) }
413 : maybedocheader 'module' modid maybemoddeprec maybeexports 'where' header_body
414 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
415 return (L loc (HsModule (Just $3) $5 $7 [] $4
417 | missing_module_keyword importdecls
418 {% fileSrcSpan >>= \ loc ->
419 return (L loc (HsModule Nothing Nothing $2 [] Nothing
420 emptyHaddockModInfo Nothing)) }
422 header_body :: { [LImportDecl RdrName] }
423 : '{' importdecls { $2 }
424 | vocurly importdecls { $2 }
426 -----------------------------------------------------------------------------
429 maybeexports :: { Maybe [LIE RdrName] }
430 : '(' exportlist ')' { Just $2 }
431 | {- empty -} { Nothing }
433 exportlist :: { [LIE RdrName] }
434 : expdoclist ',' expdoclist { $1 ++ $3 }
437 exportlist1 :: { [LIE RdrName] }
438 : expdoclist export expdoclist ',' exportlist { $1 ++ ($2 : $3) ++ $5 }
439 | expdoclist export expdoclist { $1 ++ ($2 : $3) }
442 expdoclist :: { [LIE RdrName] }
443 : exp_doc expdoclist { $1 : $2 }
446 exp_doc :: { LIE RdrName }
447 : docsection { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
448 | docnamed { L1 (IEDocNamed ((fst . unLoc) $1)) }
449 | docnext { L1 (IEDoc (unLoc $1)) }
451 -- No longer allow things like [] and (,,,) to be exported
452 -- They are built in syntax, always available
453 export :: { LIE RdrName }
454 : qvar { L1 (IEVar (unLoc $1)) }
455 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
456 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
457 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
458 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
459 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
461 qcnames :: { [RdrName] }
462 : qcnames ',' qcname_ext { unLoc $3 : $1 }
463 | qcname_ext { [unLoc $1] }
465 qcname_ext :: { Located RdrName } -- Variable or data constructor
466 -- or tagged type constructor
468 | 'type' qcon { sL (comb2 $1 $2)
469 (setRdrNameSpace (unLoc $2)
472 -- Cannot pull into qcname_ext, as qcname is also used in expression.
473 qcname :: { Located RdrName } -- Variable or data constructor
477 -----------------------------------------------------------------------------
478 -- Import Declarations
480 -- import decls can be *empty*, or even just a string of semicolons
481 -- whereas topdecls must contain at least one topdecl.
483 importdecls :: { [LImportDecl RdrName] }
484 : importdecls ';' importdecl { $3 : $1 }
485 | importdecls ';' { $1 }
486 | importdecl { [ $1 ] }
489 importdecl :: { LImportDecl RdrName }
490 : 'import' maybe_src optqualified modid maybeas maybeimpspec
491 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
493 maybe_src :: { IsBootInterface }
494 : '{-# SOURCE' '#-}' { True }
495 | {- empty -} { False }
497 optqualified :: { Bool }
498 : 'qualified' { True }
499 | {- empty -} { False }
501 maybeas :: { Located (Maybe ModuleName) }
502 : 'as' modid { LL (Just (unLoc $2)) }
503 | {- empty -} { noLoc Nothing }
505 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
506 : impspec { L1 (Just (unLoc $1)) }
507 | {- empty -} { noLoc Nothing }
509 impspec :: { Located (Bool, [LIE RdrName]) }
510 : '(' exportlist ')' { LL (False, $2) }
511 | 'hiding' '(' exportlist ')' { LL (True, $3) }
513 -----------------------------------------------------------------------------
514 -- Fixity Declarations
518 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
520 infix :: { Located FixityDirection }
521 : 'infix' { L1 InfixN }
522 | 'infixl' { L1 InfixL }
523 | 'infixr' { L1 InfixR }
525 ops :: { Located [Located RdrName] }
526 : ops ',' op { LL ($3 : unLoc $1) }
529 -----------------------------------------------------------------------------
530 -- Top-Level Declarations
532 topdecls :: { OrdList (LHsDecl RdrName) }
533 : topdecls ';' topdecl { $1 `appOL` $3 }
534 | topdecls ';' { $1 }
537 topdecl :: { OrdList (LHsDecl RdrName) }
538 : cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
539 | ty_decl { unitOL (L1 (TyClD (unLoc $1))) }
540 | 'instance' inst_type where_inst
541 { let (binds, sigs, ats, _) = cvBindsAndSigs (unLoc $3)
543 unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs ats)))}
544 | stand_alone_deriving { unitOL (LL (DerivD (unLoc $1))) }
545 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
546 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
547 | '{-# DEPRECATED' deprecations '#-}' { $2 }
548 | '{-# RULES' rules '#-}' { $2 }
551 -- Template Haskell Extension
552 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
553 | TH_ID_SPLICE { unitOL (LL $ SpliceD (SpliceDecl $
554 L1 $ HsVar (mkUnqual varName (getTH_ID_SPLICE $1))
559 cl_decl :: { LTyClDecl RdrName }
560 : 'class' tycl_hdr fds where_cls
561 {% do { let { (binds, sigs, ats, docs) =
562 cvBindsAndSigs (unLoc $4)
563 ; (ctxt, tc, tvs, tparms) = unLoc $2}
564 ; checkTyVars tparms -- only type vars allowed
566 ; return $ L (comb4 $1 $2 $3 $4)
567 (mkClassDecl (ctxt, tc, tvs)
568 (unLoc $3) sigs binds ats docs) } }
570 -- Type declarations (toplevel)
572 ty_decl :: { LTyClDecl RdrName }
573 -- ordinary type synonyms
574 : 'type' type '=' ctype
575 -- Note ctype, not sigtype, on the right of '='
576 -- We allow an explicit for-all but we don't insert one
577 -- in type Foo a = (b,b)
578 -- Instead we just say b is out of scope
580 -- Note the use of type for the head; this allows
581 -- infix type constructors to be declared
582 {% do { (tc, tvs, _) <- checkSynHdr $2 False
583 ; return (L (comb2 $1 $4)
584 (TySynonym tc tvs Nothing $4))
587 -- type family declarations
588 | 'type' 'family' type opt_kind_sig
589 -- Note the use of type for the head; this allows
590 -- infix type constructors to be declared
592 {% do { (tc, tvs, _) <- checkSynHdr $3 False
593 ; return (L (comb3 $1 $3 $4)
594 (TyFamily TypeFamily tc tvs (unLoc $4)))
597 -- type instance declarations
598 | 'type' 'instance' type '=' ctype
599 -- Note the use of type for the head; this allows
600 -- infix type constructors and type patterns
602 {% do { (tc, tvs, typats) <- checkSynHdr $3 True
603 ; return (L (comb2 $1 $5)
604 (TySynonym tc tvs (Just typats) $5))
607 -- ordinary data type or newtype declaration
608 | data_or_newtype tycl_hdr constrs deriving
609 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
610 ; checkTyVars tparms -- no type pattern
612 L (comb4 $1 $2 $3 $4)
613 -- We need the location on tycl_hdr in case
614 -- constrs and deriving are both empty
615 (mkTyData (unLoc $1) (ctxt, tc, tvs, Nothing)
616 Nothing (reverse (unLoc $3)) (unLoc $4)) } }
618 -- ordinary GADT declaration
619 | data_or_newtype tycl_hdr opt_kind_sig
620 'where' gadt_constrlist
622 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
623 ; checkTyVars tparms -- can have type pats
625 L (comb4 $1 $2 $4 $5)
626 (mkTyData (unLoc $1) (ctxt, tc, tvs, Nothing)
627 (unLoc $3) (reverse (unLoc $5)) (unLoc $6)) } }
629 -- data/newtype family
630 | 'data' 'family' tycl_hdr opt_kind_sig
631 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
632 ; checkTyVars tparms -- no type pattern
633 ; unless (null (unLoc ctxt)) $ -- and no context
634 parseError (getLoc ctxt)
635 "A family declaration cannot have a context"
638 (TyFamily DataFamily tc tvs (unLoc $4)) } }
640 -- data/newtype instance declaration
641 | data_or_newtype 'instance' tycl_hdr constrs deriving
642 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
643 -- can have type pats
645 L (comb4 $1 $3 $4 $5)
646 -- We need the location on tycl_hdr in case
647 -- constrs and deriving are both empty
648 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
649 Nothing (reverse (unLoc $4)) (unLoc $5)) } }
651 -- GADT instance declaration
652 | data_or_newtype 'instance' tycl_hdr opt_kind_sig
653 'where' gadt_constrlist
655 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
656 -- can have type pats
658 L (comb4 $1 $3 $6 $7)
659 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
660 (unLoc $4) (reverse (unLoc $6)) (unLoc $7)) } }
662 -- Associate type family declarations
664 -- * They have a different syntax than on the toplevel (no family special
667 -- * They also need to be separate from instances; otherwise, data family
668 -- declarations without a kind signature cause parsing conflicts with empty
669 -- data declarations.
671 at_decl_cls :: { LTyClDecl RdrName }
672 -- type family declarations
673 : 'type' type opt_kind_sig
674 -- Note the use of type for the head; this allows
675 -- infix type constructors to be declared
677 {% do { (tc, tvs, _) <- checkSynHdr $2 False
678 ; return (L (comb3 $1 $2 $3)
679 (TyFamily TypeFamily tc tvs (unLoc $3)))
682 -- default type instance
683 | 'type' type '=' ctype
684 -- Note the use of type for the head; this allows
685 -- infix type constructors and type patterns
687 {% do { (tc, tvs, typats) <- checkSynHdr $2 True
688 ; return (L (comb2 $1 $4)
689 (TySynonym tc tvs (Just typats) $4))
692 -- data/newtype family declaration
693 | 'data' tycl_hdr opt_kind_sig
694 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
695 ; checkTyVars tparms -- no type pattern
696 ; unless (null (unLoc ctxt)) $ -- and no context
697 parseError (getLoc ctxt)
698 "A family declaration cannot have a context"
701 (TyFamily DataFamily tc tvs (unLoc $3))
704 -- Associate type instances
706 at_decl_inst :: { LTyClDecl RdrName }
707 -- type instance declarations
708 : 'type' type '=' ctype
709 -- Note the use of type for the head; this allows
710 -- infix type constructors and type patterns
712 {% do { (tc, tvs, typats) <- checkSynHdr $2 True
713 ; return (L (comb2 $1 $4)
714 (TySynonym tc tvs (Just typats) $4))
717 -- data/newtype instance declaration
718 | data_or_newtype tycl_hdr constrs deriving
719 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
720 -- can have type pats
722 L (comb4 $1 $2 $3 $4)
723 -- We need the location on tycl_hdr in case
724 -- constrs and deriving are both empty
725 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
726 Nothing (reverse (unLoc $3)) (unLoc $4)) } }
728 -- GADT instance declaration
729 | data_or_newtype tycl_hdr opt_kind_sig
730 'where' gadt_constrlist
732 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
733 -- can have type pats
735 L (comb4 $1 $2 $5 $6)
736 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
737 (unLoc $3) (reverse (unLoc $5)) (unLoc $6)) } }
739 data_or_newtype :: { Located NewOrData }
740 : 'data' { L1 DataType }
741 | 'newtype' { L1 NewType }
743 opt_kind_sig :: { Located (Maybe Kind) }
745 | '::' kind { LL (Just (unLoc $2)) }
747 -- tycl_hdr parses the header of a class or data type decl,
748 -- which takes the form
751 -- (Eq a, Ord b) => T a b
752 -- T Int [a] -- for associated types
753 -- Rather a lot of inlining here, else we get reduce/reduce errors
754 tycl_hdr :: { Located (LHsContext RdrName,
756 [LHsTyVarBndr RdrName],
758 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
759 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
761 -----------------------------------------------------------------------------
762 -- Stand-alone deriving
764 -- Glasgow extension: stand-alone deriving declarations
765 stand_alone_deriving :: { LDerivDecl RdrName }
766 : 'deriving' 'instance' inst_type {% checkDerivDecl (LL (DerivDecl $3)) }
768 -----------------------------------------------------------------------------
769 -- Nested declarations
771 -- Declaration in class bodies
773 decl_cls :: { Located (OrdList (LHsDecl RdrName)) }
774 decl_cls : at_decl_cls { LL (unitOL (L1 (TyClD (unLoc $1)))) }
777 decls_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
778 : decls_cls ';' decl_cls { LL (unLoc $1 `appOL` unLoc $3) }
779 | decls_cls ';' { LL (unLoc $1) }
781 | {- empty -} { noLoc nilOL }
785 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
786 : '{' decls_cls '}' { LL (unLoc $2) }
787 | vocurly decls_cls close { $2 }
791 where_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
792 -- No implicit parameters
793 -- May have type declarations
794 : 'where' decllist_cls { LL (unLoc $2) }
795 | {- empty -} { noLoc nilOL }
797 -- Declarations in instance bodies
799 decl_inst :: { Located (OrdList (LHsDecl RdrName)) }
800 decl_inst : at_decl_inst { LL (unitOL (L1 (TyClD (unLoc $1)))) }
803 decls_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
804 : decls_inst ';' decl_inst { LL (unLoc $1 `appOL` unLoc $3) }
805 | decls_inst ';' { LL (unLoc $1) }
807 | {- empty -} { noLoc nilOL }
810 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
811 : '{' decls_inst '}' { LL (unLoc $2) }
812 | vocurly decls_inst close { $2 }
816 where_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
817 -- No implicit parameters
818 -- May have type declarations
819 : 'where' decllist_inst { LL (unLoc $2) }
820 | {- empty -} { noLoc nilOL }
822 -- Declarations in binding groups other than classes and instances
824 decls :: { Located (OrdList (LHsDecl RdrName)) }
825 : decls ';' decl { let { this = unLoc $3;
827 these = rest `appOL` this }
828 in rest `seq` this `seq` these `seq`
830 | decls ';' { LL (unLoc $1) }
832 | {- empty -} { noLoc nilOL }
834 decllist :: { Located (OrdList (LHsDecl RdrName)) }
835 : '{' decls '}' { LL (unLoc $2) }
836 | vocurly decls close { $2 }
838 -- Binding groups other than those of class and instance declarations
840 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
841 -- No type declarations
842 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
843 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
844 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
846 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
847 -- No type declarations
848 : 'where' binds { LL (unLoc $2) }
849 | {- empty -} { noLoc emptyLocalBinds }
852 -----------------------------------------------------------------------------
853 -- Transformation Rules
855 rules :: { OrdList (LHsDecl RdrName) }
856 : rules ';' rule { $1 `snocOL` $3 }
859 | {- empty -} { nilOL }
861 rule :: { LHsDecl RdrName }
862 : STRING activation rule_forall infixexp '=' exp
863 { LL $ RuleD (HsRule (getSTRING $1)
864 ($2 `orElse` AlwaysActive)
865 $3 $4 placeHolderNames $6 placeHolderNames) }
867 activation :: { Maybe Activation }
868 : {- empty -} { Nothing }
869 | explicit_activation { Just $1 }
871 explicit_activation :: { Activation } -- In brackets
872 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
873 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
875 rule_forall :: { [RuleBndr RdrName] }
876 : 'forall' rule_var_list '.' { $2 }
879 rule_var_list :: { [RuleBndr RdrName] }
881 | rule_var rule_var_list { $1 : $2 }
883 rule_var :: { RuleBndr RdrName }
884 : varid { RuleBndr $1 }
885 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
887 -----------------------------------------------------------------------------
888 -- Deprecations (c.f. rules)
890 deprecations :: { OrdList (LHsDecl RdrName) }
891 : deprecations ';' deprecation { $1 `appOL` $3 }
892 | deprecations ';' { $1 }
894 | {- empty -} { nilOL }
896 -- SUP: TEMPORARY HACK, not checking for `module Foo'
897 deprecation :: { OrdList (LHsDecl RdrName) }
899 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
903 -----------------------------------------------------------------------------
904 -- Foreign import and export declarations
906 fdecl :: { LHsDecl RdrName }
907 fdecl : 'import' callconv safety fspec
908 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
909 | 'import' callconv fspec
910 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
912 | 'export' callconv fspec
913 {% mkExport $2 (unLoc $3) >>= return.LL }
915 callconv :: { CallConv }
916 : 'stdcall' { CCall StdCallConv }
917 | 'ccall' { CCall CCallConv }
918 | 'dotnet' { DNCall }
921 : 'unsafe' { PlayRisky }
922 | 'safe' { PlaySafe False }
923 | 'threadsafe' { PlaySafe True }
925 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
926 : STRING var '::' sigtypedoc { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
927 | var '::' sigtypedoc { LL (noLoc nilFS, $1, $3) }
928 -- if the entity string is missing, it defaults to the empty string;
929 -- the meaning of an empty entity string depends on the calling
932 -----------------------------------------------------------------------------
935 opt_sig :: { Maybe (LHsType RdrName) }
936 : {- empty -} { Nothing }
937 | '::' sigtype { Just $2 }
939 opt_asig :: { Maybe (LHsType RdrName) }
940 : {- empty -} { Nothing }
941 | '::' atype { Just $2 }
943 sigtypes1 :: { [LHsType RdrName] }
945 | sigtype ',' sigtypes1 { $1 : $3 }
947 sigtype :: { LHsType RdrName }
948 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
949 -- Wrap an Implicit forall if there isn't one there already
951 sigtypedoc :: { LHsType RdrName }
952 : ctypedoc { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
953 -- Wrap an Implicit forall if there isn't one there already
955 sig_vars :: { Located [Located RdrName] }
956 : sig_vars ',' var { LL ($3 : unLoc $1) }
959 -----------------------------------------------------------------------------
962 infixtype :: { LHsType RdrName }
963 : btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
964 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
966 infixtypedoc :: { LHsType RdrName }
968 | infixtype docprev { LL $ HsDocTy $1 $2 }
970 gentypedoc :: { LHsType RdrName }
973 | infixtypedoc { $1 }
974 | btype '->' ctypedoc { LL $ HsFunTy $1 $3 }
975 | btypedoc '->' ctypedoc { LL $ HsFunTy $1 $3 }
977 ctypedoc :: { LHsType RdrName }
978 : 'forall' tv_bndrs '.' ctypedoc { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
979 | context '=>' ctypedoc { LL $ mkImplicitHsForAllTy $1 $3 }
980 -- A type of form (context => type) is an *implicit* HsForAllTy
983 strict_mark :: { Located HsBang }
984 : '!' { L1 HsStrict }
985 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
987 -- A ctype is a for-all type
988 ctype :: { LHsType RdrName }
989 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
990 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
991 -- A type of form (context => type) is an *implicit* HsForAllTy
994 -- We parse a context as a btype so that we don't get reduce/reduce
995 -- errors in ctype. The basic problem is that
997 -- looks so much like a tuple type. We can't tell until we find the =>
999 -- We have the t1 ~ t2 form here and in gentype, to permit an individual
1000 -- equational constraint without parenthesis.
1001 context :: { LHsContext RdrName }
1002 : btype '~' btype {% checkContext
1003 (LL $ HsPredTy (HsEqualP $1 $3)) }
1004 | btype {% checkContext $1 }
1006 type :: { LHsType RdrName }
1007 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
1010 gentype :: { LHsType RdrName }
1012 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
1013 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
1014 | btype '->' ctype { LL $ HsFunTy $1 $3 }
1015 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
1017 btype :: { LHsType RdrName }
1018 : btype atype { LL $ HsAppTy $1 $2 }
1021 btypedoc :: { LHsType RdrName }
1022 : btype atype docprev { LL $ HsDocTy (L (comb2 $1 $2) (HsAppTy $1 $2)) $3 }
1023 | atype docprev { LL $ HsDocTy $1 $2 }
1025 atype :: { LHsType RdrName }
1026 : gtycon { L1 (HsTyVar (unLoc $1)) }
1027 | tyvar { L1 (HsTyVar (unLoc $1)) }
1028 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
1029 | '(' ctype ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
1030 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
1031 | '[' ctype ']' { LL $ HsListTy $2 }
1032 | '[:' ctype ':]' { LL $ HsPArrTy $2 }
1033 | '(' ctype ')' { LL $ HsParTy $2 }
1034 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 (unLoc $4) }
1036 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
1038 -- An inst_type is what occurs in the head of an instance decl
1039 -- e.g. (Foo a, Gaz b) => Wibble a b
1040 -- It's kept as a single type, with a MonoDictTy at the right
1041 -- hand corner, for convenience.
1042 inst_type :: { LHsType RdrName }
1043 : sigtype {% checkInstType $1 }
1045 inst_types1 :: { [LHsType RdrName] }
1046 : inst_type { [$1] }
1047 | inst_type ',' inst_types1 { $1 : $3 }
1049 comma_types0 :: { [LHsType RdrName] }
1050 : comma_types1 { $1 }
1051 | {- empty -} { [] }
1053 comma_types1 :: { [LHsType RdrName] }
1055 | ctype ',' comma_types1 { $1 : $3 }
1057 tv_bndrs :: { [LHsTyVarBndr RdrName] }
1058 : tv_bndr tv_bndrs { $1 : $2 }
1059 | {- empty -} { [] }
1061 tv_bndr :: { LHsTyVarBndr RdrName }
1062 : tyvar { L1 (UserTyVar (unLoc $1)) }
1063 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2)
1066 fds :: { Located [Located ([RdrName], [RdrName])] }
1067 : {- empty -} { noLoc [] }
1068 | '|' fds1 { LL (reverse (unLoc $2)) }
1070 fds1 :: { Located [Located ([RdrName], [RdrName])] }
1071 : fds1 ',' fd { LL ($3 : unLoc $1) }
1074 fd :: { Located ([RdrName], [RdrName]) }
1075 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
1076 (reverse (unLoc $1), reverse (unLoc $3)) }
1078 varids0 :: { Located [RdrName] }
1079 : {- empty -} { noLoc [] }
1080 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
1082 -----------------------------------------------------------------------------
1085 kind :: { Located Kind }
1087 | akind '->' kind { LL (mkArrowKind (unLoc $1) (unLoc $3)) }
1089 akind :: { Located Kind }
1090 : '*' { L1 liftedTypeKind }
1091 | '!' { L1 unliftedTypeKind }
1092 | '(' kind ')' { LL (unLoc $2) }
1095 -----------------------------------------------------------------------------
1096 -- Datatype declarations
1098 gadt_constrlist :: { Located [LConDecl RdrName] }
1099 : '{' gadt_constrs '}' { LL (unLoc $2) }
1100 | vocurly gadt_constrs close { $2 }
1102 gadt_constrs :: { Located [LConDecl RdrName] }
1103 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
1104 | gadt_constrs ';' { $1 }
1105 | gadt_constr { L1 [$1] }
1107 -- We allow the following forms:
1108 -- C :: Eq a => a -> T a
1109 -- C :: forall a. Eq a => !a -> T a
1110 -- D { x,y :: a } :: T a
1111 -- forall a. Eq a => D { x,y :: a } :: T a
1113 gadt_constr :: { LConDecl RdrName }
1115 { LL (mkGadtDecl $1 $3) }
1116 -- Syntax: Maybe merge the record stuff with the single-case above?
1117 -- (to kill the mostly harmless reduce/reduce error)
1118 -- XXX revisit audreyt
1119 | constr_stuff_record '::' sigtype
1120 { let (con,details) = unLoc $1 in
1121 LL (ConDecl con Implicit [] (noLoc []) details (ResTyGADT $3) Nothing) }
1123 | forall context '=>' constr_stuff_record '::' sigtype
1124 { let (con,details) = unLoc $4 in
1125 LL (ConDecl con Implicit (unLoc $1) $2 details (ResTyGADT $6) Nothing ) }
1126 | forall constr_stuff_record '::' sigtype
1127 { let (con,details) = unLoc $2 in
1128 LL (ConDecl con Implicit (unLoc $1) (noLoc []) details (ResTyGADT $4) Nothing) }
1132 constrs :: { Located [LConDecl RdrName] }
1133 : {- empty; a GHC extension -} { noLoc [] }
1134 | maybe_docnext '=' constrs1 { L (comb2 $2 $3) (addConDocs (unLoc $3) $1) }
1136 constrs1 :: { Located [LConDecl RdrName] }
1137 : constrs1 maybe_docnext '|' maybe_docprev constr { LL (addConDoc $5 $2 : addConDocFirst (unLoc $1) $4) }
1138 | constr { L1 [$1] }
1140 constr :: { LConDecl RdrName }
1141 : maybe_docnext forall context '=>' constr_stuff maybe_docprev
1142 { let (con,details) = unLoc $5 in
1143 L (comb4 $2 $3 $4 $5) (ConDecl con Explicit (unLoc $2) $3 details ResTyH98 ($1 `mplus` $6)) }
1144 | maybe_docnext forall constr_stuff maybe_docprev
1145 { let (con,details) = unLoc $3 in
1146 L (comb2 $2 $3) (ConDecl con Explicit (unLoc $2) (noLoc []) details ResTyH98 ($1 `mplus` $4)) }
1148 forall :: { Located [LHsTyVarBndr RdrName] }
1149 : 'forall' tv_bndrs '.' { LL $2 }
1150 | {- empty -} { noLoc [] }
1152 constr_stuff :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1153 -- We parse the constructor declaration
1155 -- as a btype (treating C as a type constructor) and then convert C to be
1156 -- a data constructor. Reason: it might continue like this:
1158 -- in which case C really would be a type constructor. We can't resolve this
1159 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
1160 : btype {% mkPrefixCon $1 [] >>= return.LL }
1161 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
1162 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
1163 | btype conop btype { LL ($2, InfixCon $1 $3) }
1165 constr_stuff_record :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1166 : oqtycon '{' '}' {% mkRecCon $1 [] >>= return.sL (comb2 $1 $>) }
1167 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.sL (comb2 $1 $>) }
1169 fielddecls :: { [([Located RdrName], LBangType RdrName, Maybe (LHsDoc RdrName))] }
1170 : fielddecl maybe_docnext ',' maybe_docprev fielddecls { addFieldDoc (unLoc $1) $4 : addFieldDocs $5 $2 }
1171 | fielddecl { [unLoc $1] }
1173 fielddecl :: { Located ([Located RdrName], LBangType RdrName, Maybe (LHsDoc RdrName)) }
1174 : maybe_docnext sig_vars '::' ctype maybe_docprev { L (comb3 $2 $3 $4) (reverse (unLoc $2), $4, $1 `mplus` $5) }
1176 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
1177 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
1178 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
1179 -- We don't allow a context, but that's sorted out by the type checker.
1180 deriving :: { Located (Maybe [LHsType RdrName]) }
1181 : {- empty -} { noLoc Nothing }
1182 | 'deriving' qtycon {% do { let { L loc tv = $2 }
1183 ; p <- checkInstType (L loc (HsTyVar tv))
1184 ; return (LL (Just [p])) } }
1185 | 'deriving' '(' ')' { LL (Just []) }
1186 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
1187 -- Glasgow extension: allow partial
1188 -- applications in derivings
1190 -----------------------------------------------------------------------------
1191 -- Value definitions
1193 {- There's an awkward overlap with a type signature. Consider
1194 f :: Int -> Int = ...rhs...
1195 Then we can't tell whether it's a type signature or a value
1196 definition with a result signature until we see the '='.
1197 So we have to inline enough to postpone reductions until we know.
1201 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
1202 instead of qvar, we get another shift/reduce-conflict. Consider the
1205 { (^^) :: Int->Int ; } Type signature; only var allowed
1207 { (^^) :: Int->Int = ... ; } Value defn with result signature;
1208 qvar allowed (because of instance decls)
1210 We can't tell whether to reduce var to qvar until after we've read the signatures.
1213 docdecl :: { LHsDecl RdrName }
1214 : docdecld { L1 (DocD (unLoc $1)) }
1216 docdecld :: { LDocDecl RdrName }
1217 : docnext { L1 (DocCommentNext (unLoc $1)) }
1218 | docprev { L1 (DocCommentPrev (unLoc $1)) }
1219 | docnamed { L1 (case (unLoc $1) of (n, doc) -> DocCommentNamed n doc) }
1220 | docsection { L1 (case (unLoc $1) of (n, doc) -> DocGroup n doc) }
1222 decl :: { Located (OrdList (LHsDecl RdrName)) }
1224 | '!' aexp rhs {% do { pat <- checkPattern $2;
1225 return (LL $ unitOL $ LL $ ValD (
1226 PatBind (LL $ BangPat pat) (unLoc $3)
1227 placeHolderType placeHolderNames)) } }
1228 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
1229 let { l = comb2 $1 $> };
1230 return $! (sL l (unitOL $! (sL l $ ValD r))) } }
1231 | docdecl { LL $ unitOL $1 }
1233 rhs :: { Located (GRHSs RdrName) }
1234 : '=' exp wherebinds { sL (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
1235 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
1237 gdrhs :: { Located [LGRHS RdrName] }
1238 : gdrhs gdrh { LL ($2 : unLoc $1) }
1241 gdrh :: { LGRHS RdrName }
1242 : '|' guardquals '=' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1244 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
1245 : infixexp '::' sigtypedoc
1246 {% do s <- checkValSig $1 $3;
1247 return (LL $ unitOL (LL $ SigD s)) }
1248 -- See the above notes for why we need infixexp here
1249 | var ',' sig_vars '::' sigtypedoc
1250 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
1251 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
1253 | '{-# INLINE' activation qvar '#-}'
1254 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 (getINLINE $1)))) }
1255 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1256 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1258 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1259 { LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 (getSPEC_INLINE $1)))
1261 | '{-# SPECIALISE' 'instance' inst_type '#-}'
1262 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1264 -----------------------------------------------------------------------------
1267 exp :: { LHsExpr RdrName }
1268 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1269 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1270 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1271 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1272 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1275 infixexp :: { LHsExpr RdrName }
1277 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1279 exp10 :: { LHsExpr RdrName }
1280 : '\\' apat apats opt_asig '->' exp
1281 { LL $ HsLam (mkMatchGroup [LL $ Match ($2:$3) $4
1284 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1285 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1286 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1287 | '-' fexp { LL $ NegApp $2 noSyntaxExpr }
1289 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1290 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1291 return (L loc (mkHsDo DoExpr stmts body)) }
1292 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1293 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1294 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1295 | scc_annot exp { LL $ if opt_SccProfilingOn
1296 then HsSCC (unLoc $1) $2
1298 | hpc_annot exp { LL $ if opt_Hpc
1299 then HsTickPragma (unLoc $1) $2
1302 | 'proc' aexp '->' exp
1303 {% checkPattern $2 >>= \ p ->
1304 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1305 placeHolderType undefined)) }
1306 -- TODO: is LL right here?
1308 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1309 -- hdaume: core annotation
1312 scc_annot :: { Located FastString }
1313 : '_scc_' STRING {% (addWarning Opt_WarnDeprecations (getLoc $1) (text "_scc_ is deprecated; use an SCC pragma instead")) >>= \_ ->
1314 (return $ LL $ getSTRING $2) }
1315 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1317 hpc_annot :: { Located (FastString,(Int,Int),(Int,Int)) }
1318 : '{-# GENERATED' STRING INTEGER ':' INTEGER '-' INTEGER ':' INTEGER '#-}'
1319 { LL $ (getSTRING $2
1320 ,( fromInteger $ getINTEGER $3
1321 , fromInteger $ getINTEGER $5
1323 ,( fromInteger $ getINTEGER $7
1324 , fromInteger $ getINTEGER $9
1329 fexp :: { LHsExpr RdrName }
1330 : fexp aexp { LL $ HsApp $1 $2 }
1333 aexp :: { LHsExpr RdrName }
1334 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1335 | '~' aexp { LL $ ELazyPat $2 }
1338 aexp1 :: { LHsExpr RdrName }
1339 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4) $3
1343 -- Here was the syntax for type applications that I was planning
1344 -- but there are difficulties (e.g. what order for type args)
1345 -- so it's not enabled yet.
1346 -- But this case *is* used for the left hand side of a generic definition,
1347 -- which is parsed as an expression before being munged into a pattern
1348 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1349 (sL (getLoc $3) (HsType $3)) }
1351 aexp2 :: { LHsExpr RdrName }
1352 : ipvar { L1 (HsIPVar $! unLoc $1) }
1353 | qcname { L1 (HsVar $! unLoc $1) }
1354 | literal { L1 (HsLit $! unLoc $1) }
1355 -- This will enable overloaded strings permanently. Normally the renamer turns HsString
1356 -- into HsOverLit when -foverloaded-strings is on.
1357 -- | STRING { sL (getLoc $1) (HsOverLit $! mkHsIsString (getSTRING $1) placeHolderType) }
1358 | INTEGER { sL (getLoc $1) (HsOverLit $! mkHsIntegral (getINTEGER $1) placeHolderType) }
1359 | RATIONAL { sL (getLoc $1) (HsOverLit $! mkHsFractional (getRATIONAL $1) placeHolderType) }
1360 -- N.B.: sections get parsed by these next two productions.
1361 -- This allows you to write, e.g., '(+ 3, 4 -)', which isn't correct Haskell98
1362 -- (you'd have to write '((+ 3), (4 -))')
1363 -- but the less cluttered version fell out of having texps.
1364 | '(' texp ')' { LL (HsPar $2) }
1365 | '(' texp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1366 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1367 | '[' list ']' { LL (unLoc $2) }
1368 | '[:' parr ':]' { LL (unLoc $2) }
1369 | '_' { L1 EWildPat }
1371 -- Template Haskell Extension
1372 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1373 (L1 $ HsVar (mkUnqual varName
1374 (getTH_ID_SPLICE $1)))) } -- $x
1375 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1377 | TH_QUASIQUOTE { let { loc = getLoc $1
1378 ; ITquasiQuote (quoter, quote, quoteSpan) = unLoc $1
1379 ; quoterId = mkUnqual varName quoter
1381 in sL loc $ HsQuasiQuoteE (mkHsQuasiQuote quoterId quoteSpan quote) }
1382 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1383 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1384 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1385 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1386 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1387 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1388 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1389 return (LL $ HsBracket (PatBr p)) }
1390 | '[d|' cvtopbody '|]' {% checkDecBrGroup $2 >>= \g ->
1391 return (LL $ HsBracket (DecBr g)) }
1393 -- arrow notation extension
1394 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1396 cmdargs :: { [LHsCmdTop RdrName] }
1397 : cmdargs acmd { $2 : $1 }
1398 | {- empty -} { [] }
1400 acmd :: { LHsCmdTop RdrName }
1401 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1403 cvtopbody :: { [LHsDecl RdrName] }
1404 : '{' cvtopdecls0 '}' { $2 }
1405 | vocurly cvtopdecls0 close { $2 }
1407 cvtopdecls0 :: { [LHsDecl RdrName] }
1408 : {- empty -} { [] }
1411 -- tuple expressions: things that can appear unparenthesized as long as they're
1412 -- inside parens or delimitted by commas
1413 texp :: { LHsExpr RdrName }
1415 -- Technically, this should only be used for bang patterns,
1416 -- but we can be a little more liberal here and avoid parens
1418 | infixexp qop { LL $ SectionL $1 $2 }
1419 | qopm infixexp { LL $ SectionR $1 $2 }
1420 -- view patterns get parenthesized above
1421 | exp '->' exp { LL $ EViewPat $1 $3 }
1423 texps :: { [LHsExpr RdrName] }
1424 : texps ',' texp { $3 : $1 }
1428 -----------------------------------------------------------------------------
1431 -- The rules below are little bit contorted to keep lexps left-recursive while
1432 -- avoiding another shift/reduce-conflict.
1434 list :: { LHsExpr RdrName }
1435 : texp { L1 $ ExplicitList placeHolderType [$1] }
1436 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1437 | texp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1438 | texp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1439 | texp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1440 | texp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1441 | texp '|' flattenedpquals { sL (comb2 $1 $>) $ mkHsDo ListComp (unLoc $3) $1 }
1443 lexps :: { Located [LHsExpr RdrName] }
1444 : lexps ',' texp { LL ($3 : unLoc $1) }
1445 | texp ',' texp { LL [$3,$1] }
1447 -----------------------------------------------------------------------------
1448 -- List Comprehensions
1450 flattenedpquals :: { Located [LStmt RdrName] }
1451 : pquals { case (unLoc $1) of
1452 ParStmt [(qs, _)] -> L1 qs
1453 -- We just had one thing in our "parallel" list so
1454 -- we simply return that thing directly
1457 -- We actually found some actual parallel lists so
1458 -- we leave them into as a ParStmt
1461 pquals :: { LStmt RdrName }
1462 : pquals1 { L1 (ParStmt [(qs, undefined) | qs <- (reverse (unLoc $1))]) }
1464 pquals1 :: { Located [[LStmt RdrName]] }
1465 : pquals1 '|' squals { LL (unLoc $3 : unLoc $1) }
1466 | squals { L (getLoc $1) [unLoc $1] }
1468 squals :: { Located [LStmt RdrName] }
1469 : squals1 { L (getLoc $1) (reverse (unLoc $1)) }
1471 squals1 :: { Located [LStmt RdrName] }
1472 : transformquals1 { LL (unLoc $1) }
1474 transformquals1 :: { Located [LStmt RdrName] }
1475 : transformquals1 ',' transformqual { LL $ [LL ((unLoc $3) (unLoc $1))] }
1476 | transformquals1 ',' qual { LL ($3 : unLoc $1) }
1477 -- | transformquals1 ',' '{|' pquals '|}' { LL ($4 : unLoc $1) }
1478 | transformqual { LL $ [LL ((unLoc $1) [])] }
1480 -- | '{|' pquals '|}' { L1 [$2] }
1483 -- It is possible to enable bracketing (associating) qualifier lists by uncommenting the lines with {| |}
1484 -- above. Due to a lack of consensus on the syntax, this feature is not being used until we get user
1485 -- demand. Note that the {| |} symbols are reused from -XGenerics and hence if you want to compile
1486 -- a program that makes use of this temporary syntax you must supply that flag to GHC
1488 transformqual :: { Located ([LStmt RdrName] -> Stmt RdrName) }
1489 : 'then' exp { LL $ \leftStmts -> (mkTransformStmt (reverse leftStmts) $2) }
1490 | 'then' exp 'by' exp { LL $ \leftStmts -> (mkTransformByStmt (reverse leftStmts) $2 $4) }
1491 | 'then' 'group' 'by' exp { LL $ \leftStmts -> (mkGroupByStmt (reverse leftStmts) $4) }
1492 | 'then' 'group' 'using' exp { LL $ \leftStmts -> (mkGroupUsingStmt (reverse leftStmts) $4) }
1493 | 'then' 'group' 'by' exp 'using' exp { LL $ \leftStmts -> (mkGroupByUsingStmt (reverse leftStmts) $4 $6) }
1495 -----------------------------------------------------------------------------
1496 -- Parallel array expressions
1498 -- The rules below are little bit contorted; see the list case for details.
1499 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1500 -- Moreover, we allow explicit arrays with no element (represented by the nil
1501 -- constructor in the list case).
1503 parr :: { LHsExpr RdrName }
1504 : { noLoc (ExplicitPArr placeHolderType []) }
1505 | texp { L1 $ ExplicitPArr placeHolderType [$1] }
1506 | lexps { L1 $ ExplicitPArr placeHolderType
1507 (reverse (unLoc $1)) }
1508 | texp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1509 | texp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1510 | texp '|' flattenedpquals { LL $ mkHsDo PArrComp (unLoc $3) $1 }
1512 -- We are reusing `lexps' and `flattenedpquals' from the list case.
1514 -----------------------------------------------------------------------------
1517 guardquals :: { Located [LStmt RdrName] }
1518 : guardquals1 { L (getLoc $1) (reverse (unLoc $1)) }
1520 guardquals1 :: { Located [LStmt RdrName] }
1521 : guardquals1 ',' qual { LL ($3 : unLoc $1) }
1524 -----------------------------------------------------------------------------
1525 -- Case alternatives
1527 altslist :: { Located [LMatch RdrName] }
1528 : '{' alts '}' { LL (reverse (unLoc $2)) }
1529 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1531 alts :: { Located [LMatch RdrName] }
1532 : alts1 { L1 (unLoc $1) }
1533 | ';' alts { LL (unLoc $2) }
1535 alts1 :: { Located [LMatch RdrName] }
1536 : alts1 ';' alt { LL ($3 : unLoc $1) }
1537 | alts1 ';' { LL (unLoc $1) }
1540 alt :: { LMatch RdrName }
1541 : pat opt_sig alt_rhs { LL (Match [$1] $2 (unLoc $3)) }
1543 alt_rhs :: { Located (GRHSs RdrName) }
1544 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1546 ralt :: { Located [LGRHS RdrName] }
1547 : '->' exp { LL (unguardedRHS $2) }
1548 | gdpats { L1 (reverse (unLoc $1)) }
1550 gdpats :: { Located [LGRHS RdrName] }
1551 : gdpats gdpat { LL ($2 : unLoc $1) }
1554 gdpat :: { LGRHS RdrName }
1555 : '|' guardquals '->' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1557 -- 'pat' recognises a pattern, including one with a bang at the top
1558 -- e.g. "!x" or "!(x,y)" or "C a b" etc
1559 -- Bangs inside are parsed as infix operator applications, so that
1560 -- we parse them right when bang-patterns are off
1561 pat :: { LPat RdrName }
1562 pat : exp {% checkPattern $1 }
1563 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1565 apat :: { LPat RdrName }
1566 apat : aexp {% checkPattern $1 }
1567 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1569 apats :: { [LPat RdrName] }
1570 : apat apats { $1 : $2 }
1571 | {- empty -} { [] }
1573 -----------------------------------------------------------------------------
1574 -- Statement sequences
1576 stmtlist :: { Located [LStmt RdrName] }
1577 : '{' stmts '}' { LL (unLoc $2) }
1578 | vocurly stmts close { $2 }
1580 -- do { ;; s ; s ; ; s ;; }
1581 -- The last Stmt should be an expression, but that's hard to enforce
1582 -- here, because we need too much lookahead if we see do { e ; }
1583 -- So we use ExprStmts throughout, and switch the last one over
1584 -- in ParseUtils.checkDo instead
1585 stmts :: { Located [LStmt RdrName] }
1586 : stmt stmts_help { LL ($1 : unLoc $2) }
1587 | ';' stmts { LL (unLoc $2) }
1588 | {- empty -} { noLoc [] }
1590 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1591 : ';' stmts { LL (unLoc $2) }
1592 | {- empty -} { noLoc [] }
1594 -- For typing stmts at the GHCi prompt, where
1595 -- the input may consist of just comments.
1596 maybe_stmt :: { Maybe (LStmt RdrName) }
1598 | {- nothing -} { Nothing }
1600 stmt :: { LStmt RdrName }
1602 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1604 qual :: { LStmt RdrName }
1605 : pat '<-' exp { LL $ mkBindStmt $1 $3 }
1606 | exp { L1 $ mkExprStmt $1 }
1607 | 'let' binds { LL $ LetStmt (unLoc $2) }
1609 -----------------------------------------------------------------------------
1610 -- Record Field Update/Construction
1612 fbinds :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1614 | {- empty -} { ([], False) }
1616 fbinds1 :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1617 : fbind ',' fbinds1 { case $3 of (flds, dd) -> ($1 : flds, dd) }
1618 | fbind { ([$1], False) }
1619 | '..' { ([], True) }
1621 fbind :: { HsRecField RdrName (LHsExpr RdrName) }
1622 : qvar '=' exp { HsRecField $1 $3 False }
1623 | qvar { HsRecField $1 (L (getLoc $1) (HsVar (unLoc $1))) True }
1624 -- Here's where we say that plain 'x'
1625 -- means exactly 'x = x'. The pun-flag boolean is
1626 -- there so we can still print it right
1628 -----------------------------------------------------------------------------
1629 -- Implicit Parameter Bindings
1631 dbinds :: { Located [LIPBind RdrName] }
1632 : dbinds ';' dbind { let { this = $3; rest = unLoc $1 }
1633 in rest `seq` this `seq` LL (this : rest) }
1634 | dbinds ';' { LL (unLoc $1) }
1635 | dbind { let this = $1 in this `seq` L1 [this] }
1636 -- | {- empty -} { [] }
1638 dbind :: { LIPBind RdrName }
1639 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1641 ipvar :: { Located (IPName RdrName) }
1642 : IPDUPVARID { L1 (IPName (mkUnqual varName (getIPDUPVARID $1))) }
1644 -----------------------------------------------------------------------------
1647 depreclist :: { Located [RdrName] }
1648 depreclist : deprec_var { L1 [unLoc $1] }
1649 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1651 deprec_var :: { Located RdrName }
1652 deprec_var : var { $1 }
1655 -----------------------------------------
1656 -- Data constructors
1657 qcon :: { Located RdrName }
1659 | '(' qconsym ')' { LL (unLoc $2) }
1660 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1661 -- The case of '[:' ':]' is part of the production `parr'
1663 con :: { Located RdrName }
1665 | '(' consym ')' { LL (unLoc $2) }
1666 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1668 sysdcon :: { Located DataCon } -- Wired in data constructors
1669 : '(' ')' { LL unitDataCon }
1670 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1671 | '(#' '#)' { LL $ unboxedSingletonDataCon }
1672 | '(#' commas '#)' { LL $ tupleCon Unboxed $2 }
1673 | '[' ']' { LL nilDataCon }
1675 conop :: { Located RdrName }
1677 | '`' conid '`' { LL (unLoc $2) }
1679 qconop :: { Located RdrName }
1681 | '`' qconid '`' { LL (unLoc $2) }
1683 -----------------------------------------------------------------------------
1684 -- Type constructors
1686 gtycon :: { Located RdrName } -- A "general" qualified tycon
1688 | '(' ')' { LL $ getRdrName unitTyCon }
1689 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1690 | '(#' '#)' { LL $ getRdrName unboxedSingletonTyCon }
1691 | '(#' commas '#)' { LL $ getRdrName (tupleTyCon Unboxed $2) }
1692 | '(' '->' ')' { LL $ getRdrName funTyCon }
1693 | '[' ']' { LL $ listTyCon_RDR }
1694 | '[:' ':]' { LL $ parrTyCon_RDR }
1696 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1698 | '(' qtyconsym ')' { LL (unLoc $2) }
1700 qtyconop :: { Located RdrName } -- Qualified or unqualified
1702 | '`' qtycon '`' { LL (unLoc $2) }
1704 qtycon :: { Located RdrName } -- Qualified or unqualified
1705 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1708 tycon :: { Located RdrName } -- Unqualified
1709 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1711 qtyconsym :: { Located RdrName }
1712 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1715 tyconsym :: { Located RdrName }
1716 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1718 -----------------------------------------------------------------------------
1721 op :: { Located RdrName } -- used in infix decls
1725 varop :: { Located RdrName }
1727 | '`' varid '`' { LL (unLoc $2) }
1729 qop :: { LHsExpr RdrName } -- used in sections
1730 : qvarop { L1 $ HsVar (unLoc $1) }
1731 | qconop { L1 $ HsVar (unLoc $1) }
1733 qopm :: { LHsExpr RdrName } -- used in sections
1734 : qvaropm { L1 $ HsVar (unLoc $1) }
1735 | qconop { L1 $ HsVar (unLoc $1) }
1737 qvarop :: { Located RdrName }
1739 | '`' qvarid '`' { LL (unLoc $2) }
1741 qvaropm :: { Located RdrName }
1742 : qvarsym_no_minus { $1 }
1743 | '`' qvarid '`' { LL (unLoc $2) }
1745 -----------------------------------------------------------------------------
1748 tyvar :: { Located RdrName }
1749 tyvar : tyvarid { $1 }
1750 | '(' tyvarsym ')' { LL (unLoc $2) }
1752 tyvarop :: { Located RdrName }
1753 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1756 tyvarid :: { Located RdrName }
1757 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1758 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1759 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1760 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1761 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1763 tyvarsym :: { Located RdrName }
1764 -- Does not include "!", because that is used for strictness marks
1765 -- or ".", because that separates the quantified type vars from the rest
1766 -- or "*", because that's used for kinds
1767 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1769 -----------------------------------------------------------------------------
1772 var :: { Located RdrName }
1774 | '(' varsym ')' { LL (unLoc $2) }
1776 qvar :: { Located RdrName }
1778 | '(' varsym ')' { LL (unLoc $2) }
1779 | '(' qvarsym1 ')' { LL (unLoc $2) }
1780 -- We've inlined qvarsym here so that the decision about
1781 -- whether it's a qvar or a var can be postponed until
1782 -- *after* we see the close paren.
1784 qvarid :: { Located RdrName }
1786 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1788 varid :: { Located RdrName }
1789 : varid_no_unsafe { $1 }
1790 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1791 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1792 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1794 varid_no_unsafe :: { Located RdrName }
1795 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1796 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1797 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1798 | 'family' { L1 $! mkUnqual varName FSLIT("family") }
1800 qvarsym :: { Located RdrName }
1804 qvarsym_no_minus :: { Located RdrName }
1805 : varsym_no_minus { $1 }
1808 qvarsym1 :: { Located RdrName }
1809 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1811 varsym :: { Located RdrName }
1812 : varsym_no_minus { $1 }
1813 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1815 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1816 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1817 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1820 -- These special_ids are treated as keywords in various places,
1821 -- but as ordinary ids elsewhere. 'special_id' collects all these
1822 -- except 'unsafe', 'forall', and 'family' whose treatment differs
1823 -- depending on context
1824 special_id :: { Located FastString }
1826 : 'as' { L1 FSLIT("as") }
1827 | 'qualified' { L1 FSLIT("qualified") }
1828 | 'hiding' { L1 FSLIT("hiding") }
1829 | 'export' { L1 FSLIT("export") }
1830 | 'label' { L1 FSLIT("label") }
1831 | 'dynamic' { L1 FSLIT("dynamic") }
1832 | 'stdcall' { L1 FSLIT("stdcall") }
1833 | 'ccall' { L1 FSLIT("ccall") }
1835 special_sym :: { Located FastString }
1836 special_sym : '!' { L1 FSLIT("!") }
1837 | '.' { L1 FSLIT(".") }
1838 | '*' { L1 FSLIT("*") }
1840 -----------------------------------------------------------------------------
1841 -- Data constructors
1843 qconid :: { Located RdrName } -- Qualified or unqualified
1845 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1847 conid :: { Located RdrName }
1848 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1850 qconsym :: { Located RdrName } -- Qualified or unqualified
1852 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1854 consym :: { Located RdrName }
1855 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1857 -- ':' means only list cons
1858 | ':' { L1 $ consDataCon_RDR }
1861 -----------------------------------------------------------------------------
1864 literal :: { Located HsLit }
1865 : CHAR { L1 $ HsChar $ getCHAR $1 }
1866 | STRING { L1 $ HsString $ getSTRING $1 }
1867 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1868 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1869 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1870 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1871 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1873 -----------------------------------------------------------------------------
1877 : vccurly { () } -- context popped in lexer.
1878 | error {% popContext }
1880 -----------------------------------------------------------------------------
1881 -- Miscellaneous (mostly renamings)
1883 modid :: { Located ModuleName }
1884 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1885 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1888 (unpackFS mod ++ '.':unpackFS c))
1892 : commas ',' { $1 + 1 }
1895 -----------------------------------------------------------------------------
1896 -- Documentation comments
1898 docnext :: { LHsDoc RdrName }
1899 : DOCNEXT {% case parseHaddockParagraphs (tokenise (getDOCNEXT $1)) of {
1900 MyLeft err -> parseError (getLoc $1) err;
1901 MyRight doc -> return (L1 doc) } }
1903 docprev :: { LHsDoc RdrName }
1904 : DOCPREV {% case parseHaddockParagraphs (tokenise (getDOCPREV $1)) of {
1905 MyLeft err -> parseError (getLoc $1) err;
1906 MyRight doc -> return (L1 doc) } }
1908 docnamed :: { Located (String, (HsDoc RdrName)) }
1910 let string = getDOCNAMED $1
1911 (name, rest) = break isSpace string
1912 in case parseHaddockParagraphs (tokenise rest) of {
1913 MyLeft err -> parseError (getLoc $1) err;
1914 MyRight doc -> return (L1 (name, doc)) } }
1916 docsection :: { Located (Int, HsDoc RdrName) }
1917 : DOCSECTION {% let (n, doc) = getDOCSECTION $1 in
1918 case parseHaddockString (tokenise doc) of {
1919 MyLeft err -> parseError (getLoc $1) err;
1920 MyRight doc -> return (L1 (n, doc)) } }
1922 moduleheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
1923 : DOCNEXT {% let string = getDOCNEXT $1 in
1924 case parseModuleHeader string of {
1925 Right (str, info) ->
1926 case parseHaddockParagraphs (tokenise str) of {
1927 MyLeft err -> parseError (getLoc $1) err;
1928 MyRight doc -> return (info, Just doc);
1930 Left err -> parseError (getLoc $1) err
1933 maybe_docprev :: { Maybe (LHsDoc RdrName) }
1934 : docprev { Just $1 }
1935 | {- empty -} { Nothing }
1937 maybe_docnext :: { Maybe (LHsDoc RdrName) }
1938 : docnext { Just $1 }
1939 | {- empty -} { Nothing }
1943 happyError = srcParseFail
1945 getVARID (L _ (ITvarid x)) = x
1946 getCONID (L _ (ITconid x)) = x
1947 getVARSYM (L _ (ITvarsym x)) = x
1948 getCONSYM (L _ (ITconsym x)) = x
1949 getQVARID (L _ (ITqvarid x)) = x
1950 getQCONID (L _ (ITqconid x)) = x
1951 getQVARSYM (L _ (ITqvarsym x)) = x
1952 getQCONSYM (L _ (ITqconsym x)) = x
1953 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1954 getCHAR (L _ (ITchar x)) = x
1955 getSTRING (L _ (ITstring x)) = x
1956 getINTEGER (L _ (ITinteger x)) = x
1957 getRATIONAL (L _ (ITrational x)) = x
1958 getPRIMCHAR (L _ (ITprimchar x)) = x
1959 getPRIMSTRING (L _ (ITprimstring x)) = x
1960 getPRIMINTEGER (L _ (ITprimint x)) = x
1961 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1962 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1963 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1964 getINLINE (L _ (ITinline_prag b)) = b
1965 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
1967 getDOCNEXT (L _ (ITdocCommentNext x)) = x
1968 getDOCPREV (L _ (ITdocCommentPrev x)) = x
1969 getDOCNAMED (L _ (ITdocCommentNamed x)) = x
1970 getDOCSECTION (L _ (ITdocSection n x)) = (n, x)
1972 -- Utilities for combining source spans
1973 comb2 :: Located a -> Located b -> SrcSpan
1974 comb2 a b = a `seq` b `seq` combineLocs a b
1976 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1977 comb3 a b c = a `seq` b `seq` c `seq`
1978 combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1980 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1981 comb4 a b c d = a `seq` b `seq` c `seq` d `seq`
1982 (combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1983 combineSrcSpans (getLoc c) (getLoc d))
1985 -- strict constructor version:
1987 sL :: SrcSpan -> a -> Located a
1988 sL span a = span `seq` a `seq` L span a
1990 -- Make a source location for the file. We're a bit lazy here and just
1991 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1992 -- try to find the span of the whole file (ToDo).
1993 fileSrcSpan :: P SrcSpan
1996 let loc = mkSrcLoc (srcLocFile l) 1 0;
1997 return (mkSrcSpan loc loc)