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,
23 import HscTypes ( IsBootInterface, DeprecTxt )
26 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
27 unboxedSingletonTyCon, unboxedSingletonDataCon,
28 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
29 import Type ( funTyCon )
30 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
31 CCallConv(..), CCallTarget(..), defaultCCallConv
33 import OccName ( varName, dataName, tcClsName, tvName )
34 import DataCon ( DataCon, dataConName )
35 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
36 SrcSpan, combineLocs, srcLocFile,
39 import StaticFlags ( opt_SccProfilingOn, opt_Hpc )
40 import Type ( Kind, mkArrowKind, liftedTypeKind, unliftedTypeKind )
41 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
42 Activation(..), defaultInlineSpec )
46 import {-# SOURCE #-} HaddockLex hiding ( Token )
50 import Maybes ( orElse )
53 import Control.Monad ( unless )
56 import Control.Monad ( mplus )
60 -----------------------------------------------------------------------------
63 Conflicts: 33 shift/reduce
66 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
67 would think the two should never occur in the same context.
71 -----------------------------------------------------------------------------
74 Conflicts: 34 shift/reduce
77 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
78 would think the two should never occur in the same context.
82 -----------------------------------------------------------------------------
85 Conflicts: 32 shift/reduce
88 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
89 would think the two should never occur in the same context.
93 -----------------------------------------------------------------------------
96 Conflicts: 37 shift/reduce
99 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
100 would think the two should never occur in the same context.
104 -----------------------------------------------------------------------------
105 Conflicts: 38 shift/reduce (1.25)
107 10 for abiguity in 'if x then y else z + 1' [State 178]
108 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
109 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
111 1 for ambiguity in 'if x then y else z :: T' [State 178]
112 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
114 4 for ambiguity in 'if x then y else z -< e' [State 178]
115 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
116 There are four such operators: -<, >-, -<<, >>-
119 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
120 Which of these two is intended?
122 (x::T) -> T -- Rhs is T
125 (x::T -> T) -> .. -- Rhs is ...
127 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
130 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
131 Same duplication between states 11 and 253 as the previous case
133 1 for ambiguity in 'let ?x ...' [State 329]
134 the parser can't tell whether the ?x is the lhs of a normal binding or
135 an implicit binding. Fortunately resolving as shift gives it the only
136 sensible meaning, namely the lhs of an implicit binding.
138 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
139 we don't know whether the '[' starts the activation or not: it
140 might be the start of the declaration with the activation being
141 empty. --SDM 1/4/2002
143 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
144 since 'forall' is a valid variable name, we don't know whether
145 to treat a forall on the input as the beginning of a quantifier
146 or the beginning of the rule itself. Resolving to shift means
147 it's always treated as a quantifier, hence the above is disallowed.
148 This saves explicitly defining a grammar for the rule lhs that
149 doesn't include 'forall'.
151 1 for ambiguity when the source file starts with "-- | doc". We need another
152 token of lookahead to determine if a top declaration or the 'module' keyword
153 follows. Shift parses as if the 'module' keyword follows.
155 -- ---------------------------------------------------------------------------
156 -- Adding location info
158 This is done in a stylised way using the three macros below, L0, L1
159 and LL. Each of these macros can be thought of as having type
161 L0, L1, LL :: a -> Located a
163 They each add a SrcSpan to their argument.
165 L0 adds 'noSrcSpan', used for empty productions
166 -- This doesn't seem to work anymore -=chak
168 L1 for a production with a single token on the lhs. Grabs the SrcSpan
171 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
172 the first and last tokens.
174 These suffice for the majority of cases. However, we must be
175 especially careful with empty productions: LL won't work if the first
176 or last token on the lhs can represent an empty span. In these cases,
177 we have to calculate the span using more of the tokens from the lhs, eg.
179 | 'newtype' tycl_hdr '=' newconstr deriving
181 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
183 We provide comb3 and comb4 functions which are useful in such cases.
185 Be careful: there's no checking that you actually got this right, the
186 only symptom will be that the SrcSpans of your syntax will be
190 * We must expand these macros *before* running Happy, which is why this file is
191 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
193 #define L0 L noSrcSpan
194 #define L1 sL (getLoc $1)
195 #define LL sL (comb2 $1 $>)
197 -- -----------------------------------------------------------------------------
202 '_' { L _ ITunderscore } -- Haskell keywords
204 'case' { L _ ITcase }
205 'class' { L _ ITclass }
206 'data' { L _ ITdata }
207 'default' { L _ ITdefault }
208 'deriving' { L _ ITderiving }
210 'else' { L _ ITelse }
211 'hiding' { L _ IThiding }
213 'import' { L _ ITimport }
215 'infix' { L _ ITinfix }
216 'infixl' { L _ ITinfixl }
217 'infixr' { L _ ITinfixr }
218 'instance' { L _ ITinstance }
220 'module' { L _ ITmodule }
221 'newtype' { L _ ITnewtype }
223 'qualified' { L _ ITqualified }
224 'then' { L _ ITthen }
225 'type' { L _ ITtype }
226 'where' { L _ ITwhere }
227 '_scc_' { L _ ITscc } -- ToDo: remove
229 'forall' { L _ ITforall } -- GHC extension keywords
230 'foreign' { L _ ITforeign }
231 'export' { L _ ITexport }
232 'label' { L _ ITlabel }
233 'dynamic' { L _ ITdynamic }
234 'safe' { L _ ITsafe }
235 'threadsafe' { L _ ITthreadsafe }
236 'unsafe' { L _ ITunsafe }
238 'family' { L _ ITfamily }
239 'stdcall' { L _ ITstdcallconv }
240 'ccall' { L _ ITccallconv }
241 'dotnet' { L _ ITdotnet }
242 'proc' { L _ ITproc } -- for arrow notation extension
243 'rec' { L _ ITrec } -- for arrow notation extension
244 'group' { L _ ITgroup } -- for list transform extension
245 'by' { L _ ITby } -- for list transform extension
246 'using' { L _ ITusing } -- for list transform extension
248 '{-# INLINE' { L _ (ITinline_prag _) }
249 '{-# SPECIALISE' { L _ ITspec_prag }
250 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
251 '{-# SOURCE' { L _ ITsource_prag }
252 '{-# RULES' { L _ ITrules_prag }
253 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
254 '{-# SCC' { L _ ITscc_prag }
255 '{-# GENERATED' { L _ ITgenerated_prag }
256 '{-# DEPRECATED' { L _ ITdeprecated_prag }
257 '{-# UNPACK' { L _ ITunpack_prag }
258 '#-}' { L _ ITclose_prag }
260 '..' { L _ ITdotdot } -- reserved symbols
262 '::' { L _ ITdcolon }
266 '<-' { L _ ITlarrow }
267 '->' { L _ ITrarrow }
270 '=>' { L _ ITdarrow }
274 '-<' { L _ ITlarrowtail } -- for arrow notation
275 '>-' { L _ ITrarrowtail } -- for arrow notation
276 '-<<' { L _ ITLarrowtail } -- for arrow notation
277 '>>-' { L _ ITRarrowtail } -- for arrow notation
280 '{' { L _ ITocurly } -- special symbols
282 '{|' { L _ ITocurlybar }
283 '|}' { L _ ITccurlybar }
284 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
285 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
288 '[:' { L _ ITopabrack }
289 ':]' { L _ ITcpabrack }
292 '(#' { L _ IToubxparen }
293 '#)' { L _ ITcubxparen }
294 '(|' { L _ IToparenbar }
295 '|)' { L _ ITcparenbar }
298 '`' { L _ ITbackquote }
300 VARID { L _ (ITvarid _) } -- identifiers
301 CONID { L _ (ITconid _) }
302 VARSYM { L _ (ITvarsym _) }
303 CONSYM { L _ (ITconsym _) }
304 QVARID { L _ (ITqvarid _) }
305 QCONID { L _ (ITqconid _) }
306 QVARSYM { L _ (ITqvarsym _) }
307 QCONSYM { L _ (ITqconsym _) }
309 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
311 CHAR { L _ (ITchar _) }
312 STRING { L _ (ITstring _) }
313 INTEGER { L _ (ITinteger _) }
314 RATIONAL { L _ (ITrational _) }
316 PRIMCHAR { L _ (ITprimchar _) }
317 PRIMSTRING { L _ (ITprimstring _) }
318 PRIMINTEGER { L _ (ITprimint _) }
319 PRIMFLOAT { L _ (ITprimfloat _) }
320 PRIMDOUBLE { L _ (ITprimdouble _) }
322 DOCNEXT { L _ (ITdocCommentNext _) }
323 DOCPREV { L _ (ITdocCommentPrev _) }
324 DOCNAMED { L _ (ITdocCommentNamed _) }
325 DOCSECTION { L _ (ITdocSection _ _) }
328 '[|' { L _ ITopenExpQuote }
329 '[p|' { L _ ITopenPatQuote }
330 '[t|' { L _ ITopenTypQuote }
331 '[d|' { L _ ITopenDecQuote }
332 '|]' { L _ ITcloseQuote }
333 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
334 '$(' { L _ ITparenEscape } -- $( exp )
335 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
336 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
337 TH_QUASIQUOTE { L _ (ITquasiQuote _) }
339 %monad { P } { >>= } { return }
340 %lexer { lexer } { L _ ITeof }
341 %name parseModule module
342 %name parseStmt maybe_stmt
343 %name parseIdentifier identifier
344 %name parseType ctype
345 %partial parseHeader header
346 %tokentype { (Located Token) }
349 -----------------------------------------------------------------------------
350 -- Identifiers; one of the entry points
351 identifier :: { Located RdrName }
356 | '(' '->' ')' { LL $ getRdrName funTyCon }
358 -----------------------------------------------------------------------------
361 -- The place for module deprecation is really too restrictive, but if it
362 -- was allowed at its natural place just before 'module', we get an ugly
363 -- s/r conflict with the second alternative. Another solution would be the
364 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
365 -- either, and DEPRECATED is only expected to be used by people who really
366 -- know what they are doing. :-)
368 module :: { Located (HsModule RdrName) }
369 : maybedocheader 'module' modid maybemoddeprec maybeexports 'where' body
370 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
371 return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4
374 {% fileSrcSpan >>= \ loc ->
375 return (L loc (HsModule Nothing Nothing
376 (fst $1) (snd $1) Nothing emptyHaddockModInfo
379 maybedocheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
380 : moduleheader { (fst $1, snd $1) }
381 | {- empty -} { (emptyHaddockModInfo, Nothing) }
383 missing_module_keyword :: { () }
384 : {- empty -} {% pushCurrentContext }
386 maybemoddeprec :: { Maybe DeprecTxt }
387 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
388 | {- empty -} { Nothing }
390 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
392 | vocurly top close { $2 }
394 body2 :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
396 | missing_module_keyword top close { $2 }
398 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
399 : importdecls { (reverse $1,[]) }
400 | importdecls ';' cvtopdecls { (reverse $1,$3) }
401 | cvtopdecls { ([],$1) }
403 cvtopdecls :: { [LHsDecl RdrName] }
404 : topdecls { cvTopDecls $1 }
406 -----------------------------------------------------------------------------
407 -- Module declaration & imports only
409 header :: { Located (HsModule RdrName) }
410 : maybedocheader 'module' modid maybemoddeprec maybeexports 'where' header_body
411 {% fileSrcSpan >>= \ loc -> case $1 of { (info, doc) ->
412 return (L loc (HsModule (Just $3) $5 $7 [] $4
414 | missing_module_keyword importdecls
415 {% fileSrcSpan >>= \ loc ->
416 return (L loc (HsModule Nothing Nothing $2 [] Nothing
417 emptyHaddockModInfo Nothing)) }
419 header_body :: { [LImportDecl RdrName] }
420 : '{' importdecls { $2 }
421 | vocurly importdecls { $2 }
423 -----------------------------------------------------------------------------
426 maybeexports :: { Maybe [LIE RdrName] }
427 : '(' exportlist ')' { Just $2 }
428 | {- empty -} { Nothing }
430 exportlist :: { [LIE RdrName] }
431 : expdoclist ',' expdoclist { $1 ++ $3 }
434 exportlist1 :: { [LIE RdrName] }
435 : expdoclist export expdoclist ',' exportlist { $1 ++ ($2 : $3) ++ $5 }
436 | expdoclist export expdoclist { $1 ++ ($2 : $3) }
439 expdoclist :: { [LIE RdrName] }
440 : exp_doc expdoclist { $1 : $2 }
443 exp_doc :: { LIE RdrName }
444 : docsection { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
445 | docnamed { L1 (IEDocNamed ((fst . unLoc) $1)) }
446 | docnext { L1 (IEDoc (unLoc $1)) }
448 -- No longer allow things like [] and (,,,) to be exported
449 -- They are built in syntax, always available
450 export :: { LIE RdrName }
451 : qvar { L1 (IEVar (unLoc $1)) }
452 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
453 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
454 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
455 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
456 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
458 qcnames :: { [RdrName] }
459 : qcnames ',' qcname_ext { unLoc $3 : $1 }
460 | qcname_ext { [unLoc $1] }
462 qcname_ext :: { Located RdrName } -- Variable or data constructor
463 -- or tagged type constructor
465 | 'type' qcon { sL (comb2 $1 $2)
466 (setRdrNameSpace (unLoc $2)
469 -- Cannot pull into qcname_ext, as qcname is also used in expression.
470 qcname :: { Located RdrName } -- Variable or data constructor
474 -----------------------------------------------------------------------------
475 -- Import Declarations
477 -- import decls can be *empty*, or even just a string of semicolons
478 -- whereas topdecls must contain at least one topdecl.
480 importdecls :: { [LImportDecl RdrName] }
481 : importdecls ';' importdecl { $3 : $1 }
482 | importdecls ';' { $1 }
483 | importdecl { [ $1 ] }
486 importdecl :: { LImportDecl RdrName }
487 : 'import' maybe_src optqualified modid maybeas maybeimpspec
488 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
490 maybe_src :: { IsBootInterface }
491 : '{-# SOURCE' '#-}' { True }
492 | {- empty -} { False }
494 optqualified :: { Bool }
495 : 'qualified' { True }
496 | {- empty -} { False }
498 maybeas :: { Located (Maybe ModuleName) }
499 : 'as' modid { LL (Just (unLoc $2)) }
500 | {- empty -} { noLoc Nothing }
502 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
503 : impspec { L1 (Just (unLoc $1)) }
504 | {- empty -} { noLoc Nothing }
506 impspec :: { Located (Bool, [LIE RdrName]) }
507 : '(' exportlist ')' { LL (False, $2) }
508 | 'hiding' '(' exportlist ')' { LL (True, $3) }
510 -----------------------------------------------------------------------------
511 -- Fixity Declarations
515 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
517 infix :: { Located FixityDirection }
518 : 'infix' { L1 InfixN }
519 | 'infixl' { L1 InfixL }
520 | 'infixr' { L1 InfixR }
522 ops :: { Located [Located RdrName] }
523 : ops ',' op { LL ($3 : unLoc $1) }
526 -----------------------------------------------------------------------------
527 -- Top-Level Declarations
529 topdecls :: { OrdList (LHsDecl RdrName) }
530 : topdecls ';' topdecl { $1 `appOL` $3 }
531 | topdecls ';' { $1 }
534 topdecl :: { OrdList (LHsDecl RdrName) }
535 : cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
536 | ty_decl { unitOL (L1 (TyClD (unLoc $1))) }
537 | 'instance' inst_type where_inst
538 { let (binds, sigs, ats, _) = cvBindsAndSigs (unLoc $3)
540 unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs ats)))}
541 | stand_alone_deriving { unitOL (LL (DerivD (unLoc $1))) }
542 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
543 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
544 | '{-# DEPRECATED' deprecations '#-}' { $2 }
545 | '{-# RULES' rules '#-}' { $2 }
548 -- Template Haskell Extension
549 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
550 | TH_ID_SPLICE { unitOL (LL $ SpliceD (SpliceDecl $
551 L1 $ HsVar (mkUnqual varName (getTH_ID_SPLICE $1))
556 cl_decl :: { LTyClDecl RdrName }
557 : 'class' tycl_hdr fds where_cls
558 {% do { let { (binds, sigs, ats, docs) =
559 cvBindsAndSigs (unLoc $4)
560 ; (ctxt, tc, tvs, tparms) = unLoc $2}
561 ; checkTyVars tparms -- only type vars allowed
563 ; return $ L (comb4 $1 $2 $3 $4)
564 (mkClassDecl (ctxt, tc, tvs)
565 (unLoc $3) sigs binds ats docs) } }
567 -- Type declarations (toplevel)
569 ty_decl :: { LTyClDecl RdrName }
570 -- ordinary type synonyms
571 : 'type' type '=' ctype
572 -- Note ctype, not sigtype, on the right of '='
573 -- We allow an explicit for-all but we don't insert one
574 -- in type Foo a = (b,b)
575 -- Instead we just say b is out of scope
577 -- Note the use of type for the head; this allows
578 -- infix type constructors to be declared
579 {% do { (tc, tvs, _) <- checkSynHdr $2 False
580 ; return (L (comb2 $1 $4)
581 (TySynonym tc tvs Nothing $4))
584 -- type family declarations
585 | 'type' 'family' type opt_kind_sig
586 -- Note the use of type for the head; this allows
587 -- infix type constructors to be declared
589 {% do { (tc, tvs, _) <- checkSynHdr $3 False
590 ; return (L (comb3 $1 $3 $4)
591 (TyFamily TypeFamily tc tvs (unLoc $4)))
594 -- type instance declarations
595 | 'type' 'instance' type '=' ctype
596 -- Note the use of type for the head; this allows
597 -- infix type constructors and type patterns
599 {% do { (tc, tvs, typats) <- checkSynHdr $3 True
600 ; return (L (comb2 $1 $5)
601 (TySynonym tc tvs (Just typats) $5))
604 -- ordinary data type or newtype declaration
605 | data_or_newtype tycl_hdr constrs deriving
606 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
607 ; checkTyVars tparms -- no type pattern
609 L (comb4 $1 $2 $3 $4)
610 -- We need the location on tycl_hdr in case
611 -- constrs and deriving are both empty
612 (mkTyData (unLoc $1) (ctxt, tc, tvs, Nothing)
613 Nothing (reverse (unLoc $3)) (unLoc $4)) } }
615 -- ordinary GADT declaration
616 | data_or_newtype tycl_hdr opt_kind_sig
617 'where' gadt_constrlist
619 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
620 ; checkTyVars tparms -- can have type pats
622 L (comb4 $1 $2 $4 $5)
623 (mkTyData (unLoc $1) (ctxt, tc, tvs, Nothing)
624 (unLoc $3) (reverse (unLoc $5)) (unLoc $6)) } }
626 -- data/newtype family
627 | 'data' 'family' tycl_hdr opt_kind_sig
628 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
629 ; checkTyVars tparms -- no type pattern
630 ; unless (null (unLoc ctxt)) $ -- and no context
631 parseError (getLoc ctxt)
632 "A family declaration cannot have a context"
635 (TyFamily DataFamily tc tvs (unLoc $4)) } }
637 -- data/newtype instance declaration
638 | data_or_newtype 'instance' tycl_hdr constrs deriving
639 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
640 -- can have type pats
642 L (comb4 $1 $3 $4 $5)
643 -- We need the location on tycl_hdr in case
644 -- constrs and deriving are both empty
645 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
646 Nothing (reverse (unLoc $4)) (unLoc $5)) } }
648 -- GADT instance declaration
649 | data_or_newtype 'instance' tycl_hdr opt_kind_sig
650 'where' gadt_constrlist
652 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $3}
653 -- can have type pats
655 L (comb4 $1 $3 $6 $7)
656 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
657 (unLoc $4) (reverse (unLoc $6)) (unLoc $7)) } }
659 -- Associate type family declarations
661 -- * They have a different syntax than on the toplevel (no family special
664 -- * They also need to be separate from instances; otherwise, data family
665 -- declarations without a kind signature cause parsing conflicts with empty
666 -- data declarations.
668 at_decl_cls :: { LTyClDecl RdrName }
669 -- type family declarations
670 : 'type' type opt_kind_sig
671 -- Note the use of type for the head; this allows
672 -- infix type constructors to be declared
674 {% do { (tc, tvs, _) <- checkSynHdr $2 False
675 ; return (L (comb3 $1 $2 $3)
676 (TyFamily TypeFamily tc tvs (unLoc $3)))
679 -- default type instance
680 | 'type' type '=' ctype
681 -- Note the use of type for the head; this allows
682 -- infix type constructors and type patterns
684 {% do { (tc, tvs, typats) <- checkSynHdr $2 True
685 ; return (L (comb2 $1 $4)
686 (TySynonym tc tvs (Just typats) $4))
689 -- data/newtype family declaration
690 | 'data' tycl_hdr opt_kind_sig
691 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
692 ; checkTyVars tparms -- no type pattern
693 ; unless (null (unLoc ctxt)) $ -- and no context
694 parseError (getLoc ctxt)
695 "A family declaration cannot have a context"
698 (TyFamily DataFamily tc tvs (unLoc $3))
701 -- Associate type instances
703 at_decl_inst :: { LTyClDecl RdrName }
704 -- type instance declarations
705 : 'type' type '=' ctype
706 -- Note the use of type for the head; this allows
707 -- infix type constructors and type patterns
709 {% do { (tc, tvs, typats) <- checkSynHdr $2 True
710 ; return (L (comb2 $1 $4)
711 (TySynonym tc tvs (Just typats) $4))
714 -- data/newtype instance declaration
715 | data_or_newtype tycl_hdr constrs deriving
716 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
717 -- can have type pats
719 L (comb4 $1 $2 $3 $4)
720 -- We need the location on tycl_hdr in case
721 -- constrs and deriving are both empty
722 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
723 Nothing (reverse (unLoc $3)) (unLoc $4)) } }
725 -- GADT instance declaration
726 | data_or_newtype tycl_hdr opt_kind_sig
727 'where' gadt_constrlist
729 {% do { let {(ctxt, tc, tvs, tparms) = unLoc $2}
730 -- can have type pats
732 L (comb4 $1 $2 $5 $6)
733 (mkTyData (unLoc $1) (ctxt, tc, tvs, Just tparms)
734 (unLoc $3) (reverse (unLoc $5)) (unLoc $6)) } }
736 data_or_newtype :: { Located NewOrData }
737 : 'data' { L1 DataType }
738 | 'newtype' { L1 NewType }
740 opt_kind_sig :: { Located (Maybe Kind) }
742 | '::' kind { LL (Just (unLoc $2)) }
744 -- tycl_hdr parses the header of a class or data type decl,
745 -- which takes the form
748 -- (Eq a, Ord b) => T a b
749 -- T Int [a] -- for associated types
750 -- Rather a lot of inlining here, else we get reduce/reduce errors
751 tycl_hdr :: { Located (LHsContext RdrName,
753 [LHsTyVarBndr RdrName],
755 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
756 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
758 -----------------------------------------------------------------------------
759 -- Stand-alone deriving
761 -- Glasgow extension: stand-alone deriving declarations
762 stand_alone_deriving :: { LDerivDecl RdrName }
763 : 'deriving' 'instance' inst_type {% checkDerivDecl (LL (DerivDecl $3)) }
765 -----------------------------------------------------------------------------
766 -- Nested declarations
768 -- Declaration in class bodies
770 decl_cls :: { Located (OrdList (LHsDecl RdrName)) }
771 decl_cls : at_decl_cls { LL (unitOL (L1 (TyClD (unLoc $1)))) }
774 decls_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
775 : decls_cls ';' decl_cls { LL (unLoc $1 `appOL` unLoc $3) }
776 | decls_cls ';' { LL (unLoc $1) }
778 | {- empty -} { noLoc nilOL }
782 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
783 : '{' decls_cls '}' { LL (unLoc $2) }
784 | vocurly decls_cls close { $2 }
788 where_cls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
789 -- No implicit parameters
790 -- May have type declarations
791 : 'where' decllist_cls { LL (unLoc $2) }
792 | {- empty -} { noLoc nilOL }
794 -- Declarations in instance bodies
796 decl_inst :: { Located (OrdList (LHsDecl RdrName)) }
797 decl_inst : at_decl_inst { LL (unitOL (L1 (TyClD (unLoc $1)))) }
800 decls_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
801 : decls_inst ';' decl_inst { LL (unLoc $1 `appOL` unLoc $3) }
802 | decls_inst ';' { LL (unLoc $1) }
804 | {- empty -} { noLoc nilOL }
807 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
808 : '{' decls_inst '}' { LL (unLoc $2) }
809 | vocurly decls_inst close { $2 }
813 where_inst :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
814 -- No implicit parameters
815 -- May have type declarations
816 : 'where' decllist_inst { LL (unLoc $2) }
817 | {- empty -} { noLoc nilOL }
819 -- Declarations in binding groups other than classes and instances
821 decls :: { Located (OrdList (LHsDecl RdrName)) }
822 : decls ';' decl { let { this = unLoc $3;
824 these = rest `appOL` this }
825 in rest `seq` this `seq` these `seq`
827 | decls ';' { LL (unLoc $1) }
829 | {- empty -} { noLoc nilOL }
831 decllist :: { Located (OrdList (LHsDecl RdrName)) }
832 : '{' decls '}' { LL (unLoc $2) }
833 | vocurly decls close { $2 }
835 -- Binding groups other than those of class and instance declarations
837 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
838 -- No type declarations
839 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
840 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
841 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
843 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
844 -- No type declarations
845 : 'where' binds { LL (unLoc $2) }
846 | {- empty -} { noLoc emptyLocalBinds }
849 -----------------------------------------------------------------------------
850 -- Transformation Rules
852 rules :: { OrdList (LHsDecl RdrName) }
853 : rules ';' rule { $1 `snocOL` $3 }
856 | {- empty -} { nilOL }
858 rule :: { LHsDecl RdrName }
859 : STRING activation rule_forall infixexp '=' exp
860 { LL $ RuleD (HsRule (getSTRING $1)
861 ($2 `orElse` AlwaysActive)
862 $3 $4 placeHolderNames $6 placeHolderNames) }
864 activation :: { Maybe Activation }
865 : {- empty -} { Nothing }
866 | explicit_activation { Just $1 }
868 explicit_activation :: { Activation } -- In brackets
869 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
870 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
872 rule_forall :: { [RuleBndr RdrName] }
873 : 'forall' rule_var_list '.' { $2 }
876 rule_var_list :: { [RuleBndr RdrName] }
878 | rule_var rule_var_list { $1 : $2 }
880 rule_var :: { RuleBndr RdrName }
881 : varid { RuleBndr $1 }
882 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
884 -----------------------------------------------------------------------------
885 -- Deprecations (c.f. rules)
887 deprecations :: { OrdList (LHsDecl RdrName) }
888 : deprecations ';' deprecation { $1 `appOL` $3 }
889 | deprecations ';' { $1 }
891 | {- empty -} { nilOL }
893 -- SUP: TEMPORARY HACK, not checking for `module Foo'
894 deprecation :: { OrdList (LHsDecl RdrName) }
896 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
900 -----------------------------------------------------------------------------
901 -- Foreign import and export declarations
903 fdecl :: { LHsDecl RdrName }
904 fdecl : 'import' callconv safety fspec
905 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
906 | 'import' callconv fspec
907 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
909 | 'export' callconv fspec
910 {% mkExport $2 (unLoc $3) >>= return.LL }
912 callconv :: { CallConv }
913 : 'stdcall' { CCall StdCallConv }
914 | 'ccall' { CCall CCallConv }
915 | 'dotnet' { DNCall }
918 : 'unsafe' { PlayRisky }
919 | 'safe' { PlaySafe False }
920 | 'threadsafe' { PlaySafe True }
922 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
923 : STRING var '::' sigtypedoc { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
924 | var '::' sigtypedoc { LL (noLoc nilFS, $1, $3) }
925 -- if the entity string is missing, it defaults to the empty string;
926 -- the meaning of an empty entity string depends on the calling
929 -----------------------------------------------------------------------------
932 opt_sig :: { Maybe (LHsType RdrName) }
933 : {- empty -} { Nothing }
934 | '::' sigtype { Just $2 }
936 opt_asig :: { Maybe (LHsType RdrName) }
937 : {- empty -} { Nothing }
938 | '::' atype { Just $2 }
940 sigtypes1 :: { [LHsType RdrName] }
942 | sigtype ',' sigtypes1 { $1 : $3 }
944 sigtype :: { LHsType RdrName }
945 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
946 -- Wrap an Implicit forall if there isn't one there already
948 sigtypedoc :: { LHsType RdrName }
949 : ctypedoc { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
950 -- Wrap an Implicit forall if there isn't one there already
952 sig_vars :: { Located [Located RdrName] }
953 : sig_vars ',' var { LL ($3 : unLoc $1) }
956 -----------------------------------------------------------------------------
959 infixtype :: { LHsType RdrName }
960 : btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
961 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
963 infixtypedoc :: { LHsType RdrName }
965 | infixtype docprev { LL $ HsDocTy $1 $2 }
967 gentypedoc :: { LHsType RdrName }
970 | infixtypedoc { $1 }
971 | btype '->' ctypedoc { LL $ HsFunTy $1 $3 }
972 | btypedoc '->' ctypedoc { LL $ HsFunTy $1 $3 }
974 ctypedoc :: { LHsType RdrName }
975 : 'forall' tv_bndrs '.' ctypedoc { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
976 | context '=>' ctypedoc { LL $ mkImplicitHsForAllTy $1 $3 }
977 -- A type of form (context => type) is an *implicit* HsForAllTy
980 strict_mark :: { Located HsBang }
981 : '!' { L1 HsStrict }
982 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
984 -- A ctype is a for-all type
985 ctype :: { LHsType RdrName }
986 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
987 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
988 -- A type of form (context => type) is an *implicit* HsForAllTy
991 -- We parse a context as a btype so that we don't get reduce/reduce
992 -- errors in ctype. The basic problem is that
994 -- looks so much like a tuple type. We can't tell until we find the =>
996 -- We have the t1 ~ t2 form here and in gentype, to permit an individual
997 -- equational constraint without parenthesis.
998 context :: { LHsContext RdrName }
999 : btype '~' btype {% checkContext
1000 (LL $ HsPredTy (HsEqualP $1 $3)) }
1001 | btype {% checkContext $1 }
1003 type :: { LHsType RdrName }
1004 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
1007 gentype :: { LHsType RdrName }
1009 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
1010 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
1011 | btype '->' ctype { LL $ HsFunTy $1 $3 }
1012 | btype '~' btype { LL $ HsPredTy (HsEqualP $1 $3) }
1014 btype :: { LHsType RdrName }
1015 : btype atype { LL $ HsAppTy $1 $2 }
1018 btypedoc :: { LHsType RdrName }
1019 : btype atype docprev { LL $ HsDocTy (L (comb2 $1 $2) (HsAppTy $1 $2)) $3 }
1020 | atype docprev { LL $ HsDocTy $1 $2 }
1022 atype :: { LHsType RdrName }
1023 : gtycon { L1 (HsTyVar (unLoc $1)) }
1024 | tyvar { L1 (HsTyVar (unLoc $1)) }
1025 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
1026 | '(' ctype ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
1027 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
1028 | '[' ctype ']' { LL $ HsListTy $2 }
1029 | '[:' ctype ':]' { LL $ HsPArrTy $2 }
1030 | '(' ctype ')' { LL $ HsParTy $2 }
1031 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 (unLoc $4) }
1033 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
1035 -- An inst_type is what occurs in the head of an instance decl
1036 -- e.g. (Foo a, Gaz b) => Wibble a b
1037 -- It's kept as a single type, with a MonoDictTy at the right
1038 -- hand corner, for convenience.
1039 inst_type :: { LHsType RdrName }
1040 : sigtype {% checkInstType $1 }
1042 inst_types1 :: { [LHsType RdrName] }
1043 : inst_type { [$1] }
1044 | inst_type ',' inst_types1 { $1 : $3 }
1046 comma_types0 :: { [LHsType RdrName] }
1047 : comma_types1 { $1 }
1048 | {- empty -} { [] }
1050 comma_types1 :: { [LHsType RdrName] }
1052 | ctype ',' comma_types1 { $1 : $3 }
1054 tv_bndrs :: { [LHsTyVarBndr RdrName] }
1055 : tv_bndr tv_bndrs { $1 : $2 }
1056 | {- empty -} { [] }
1058 tv_bndr :: { LHsTyVarBndr RdrName }
1059 : tyvar { L1 (UserTyVar (unLoc $1)) }
1060 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2)
1063 fds :: { Located [Located ([RdrName], [RdrName])] }
1064 : {- empty -} { noLoc [] }
1065 | '|' fds1 { LL (reverse (unLoc $2)) }
1067 fds1 :: { Located [Located ([RdrName], [RdrName])] }
1068 : fds1 ',' fd { LL ($3 : unLoc $1) }
1071 fd :: { Located ([RdrName], [RdrName]) }
1072 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
1073 (reverse (unLoc $1), reverse (unLoc $3)) }
1075 varids0 :: { Located [RdrName] }
1076 : {- empty -} { noLoc [] }
1077 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
1079 -----------------------------------------------------------------------------
1082 kind :: { Located Kind }
1084 | akind '->' kind { LL (mkArrowKind (unLoc $1) (unLoc $3)) }
1086 akind :: { Located Kind }
1087 : '*' { L1 liftedTypeKind }
1088 | '!' { L1 unliftedTypeKind }
1089 | '(' kind ')' { LL (unLoc $2) }
1092 -----------------------------------------------------------------------------
1093 -- Datatype declarations
1095 gadt_constrlist :: { Located [LConDecl RdrName] }
1096 : '{' gadt_constrs '}' { LL (unLoc $2) }
1097 | vocurly gadt_constrs close { $2 }
1099 gadt_constrs :: { Located [LConDecl RdrName] }
1100 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
1101 | gadt_constrs ';' { $1 }
1102 | gadt_constr { L1 [$1] }
1104 -- We allow the following forms:
1105 -- C :: Eq a => a -> T a
1106 -- C :: forall a. Eq a => !a -> T a
1107 -- D { x,y :: a } :: T a
1108 -- forall a. Eq a => D { x,y :: a } :: T a
1110 gadt_constr :: { LConDecl RdrName }
1112 { LL (mkGadtDecl $1 $3) }
1113 -- Syntax: Maybe merge the record stuff with the single-case above?
1114 -- (to kill the mostly harmless reduce/reduce error)
1115 -- XXX revisit audreyt
1116 | constr_stuff_record '::' sigtype
1117 { let (con,details) = unLoc $1 in
1118 LL (ConDecl con Implicit [] (noLoc []) details (ResTyGADT $3) Nothing) }
1120 | forall context '=>' constr_stuff_record '::' sigtype
1121 { let (con,details) = unLoc $4 in
1122 LL (ConDecl con Implicit (unLoc $1) $2 details (ResTyGADT $6) Nothing ) }
1123 | forall constr_stuff_record '::' sigtype
1124 { let (con,details) = unLoc $2 in
1125 LL (ConDecl con Implicit (unLoc $1) (noLoc []) details (ResTyGADT $4) Nothing) }
1129 constrs :: { Located [LConDecl RdrName] }
1130 : {- empty; a GHC extension -} { noLoc [] }
1131 | maybe_docnext '=' constrs1 { L (comb2 $2 $3) (addConDocs (unLoc $3) $1) }
1133 constrs1 :: { Located [LConDecl RdrName] }
1134 : constrs1 maybe_docnext '|' maybe_docprev constr { LL (addConDoc $5 $2 : addConDocFirst (unLoc $1) $4) }
1135 | constr { L1 [$1] }
1137 constr :: { LConDecl RdrName }
1138 : maybe_docnext forall context '=>' constr_stuff maybe_docprev
1139 { let (con,details) = unLoc $5 in
1140 L (comb4 $2 $3 $4 $5) (ConDecl con Explicit (unLoc $2) $3 details ResTyH98 ($1 `mplus` $6)) }
1141 | maybe_docnext forall constr_stuff maybe_docprev
1142 { let (con,details) = unLoc $3 in
1143 L (comb2 $2 $3) (ConDecl con Explicit (unLoc $2) (noLoc []) details ResTyH98 ($1 `mplus` $4)) }
1145 forall :: { Located [LHsTyVarBndr RdrName] }
1146 : 'forall' tv_bndrs '.' { LL $2 }
1147 | {- empty -} { noLoc [] }
1149 constr_stuff :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1150 -- We parse the constructor declaration
1152 -- as a btype (treating C as a type constructor) and then convert C to be
1153 -- a data constructor. Reason: it might continue like this:
1155 -- in which case C really would be a type constructor. We can't resolve this
1156 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
1157 : btype {% mkPrefixCon $1 [] >>= return.LL }
1158 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
1159 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
1160 | btype conop btype { LL ($2, InfixCon $1 $3) }
1162 constr_stuff_record :: { Located (Located RdrName, HsConDeclDetails RdrName) }
1163 : oqtycon '{' '}' {% mkRecCon $1 [] >>= return.sL (comb2 $1 $>) }
1164 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.sL (comb2 $1 $>) }
1166 fielddecls :: { [([Located RdrName], LBangType RdrName, Maybe (LHsDoc RdrName))] }
1167 : fielddecl maybe_docnext ',' maybe_docprev fielddecls { addFieldDoc (unLoc $1) $4 : addFieldDocs $5 $2 }
1168 | fielddecl { [unLoc $1] }
1170 fielddecl :: { Located ([Located RdrName], LBangType RdrName, Maybe (LHsDoc RdrName)) }
1171 : maybe_docnext sig_vars '::' ctype maybe_docprev { L (comb3 $2 $3 $4) (reverse (unLoc $2), $4, $1 `mplus` $5) }
1173 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
1174 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
1175 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
1176 -- We don't allow a context, but that's sorted out by the type checker.
1177 deriving :: { Located (Maybe [LHsType RdrName]) }
1178 : {- empty -} { noLoc Nothing }
1179 | 'deriving' qtycon {% do { let { L loc tv = $2 }
1180 ; p <- checkInstType (L loc (HsTyVar tv))
1181 ; return (LL (Just [p])) } }
1182 | 'deriving' '(' ')' { LL (Just []) }
1183 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
1184 -- Glasgow extension: allow partial
1185 -- applications in derivings
1187 -----------------------------------------------------------------------------
1188 -- Value definitions
1190 {- There's an awkward overlap with a type signature. Consider
1191 f :: Int -> Int = ...rhs...
1192 Then we can't tell whether it's a type signature or a value
1193 definition with a result signature until we see the '='.
1194 So we have to inline enough to postpone reductions until we know.
1198 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
1199 instead of qvar, we get another shift/reduce-conflict. Consider the
1202 { (^^) :: Int->Int ; } Type signature; only var allowed
1204 { (^^) :: Int->Int = ... ; } Value defn with result signature;
1205 qvar allowed (because of instance decls)
1207 We can't tell whether to reduce var to qvar until after we've read the signatures.
1210 docdecl :: { LHsDecl RdrName }
1211 : docdecld { L1 (DocD (unLoc $1)) }
1213 docdecld :: { LDocDecl RdrName }
1214 : docnext { L1 (DocCommentNext (unLoc $1)) }
1215 | docprev { L1 (DocCommentPrev (unLoc $1)) }
1216 | docnamed { L1 (case (unLoc $1) of (n, doc) -> DocCommentNamed n doc) }
1217 | docsection { L1 (case (unLoc $1) of (n, doc) -> DocGroup n doc) }
1219 decl :: { Located (OrdList (LHsDecl RdrName)) }
1221 | '!' aexp rhs {% do { pat <- checkPattern $2;
1222 return (LL $ unitOL $ LL $ ValD (
1223 PatBind (LL $ BangPat pat) (unLoc $3)
1224 placeHolderType placeHolderNames)) } }
1225 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
1226 let { l = comb2 $1 $> };
1227 return $! (sL l (unitOL $! (sL l $ ValD r))) } }
1228 | docdecl { LL $ unitOL $1 }
1230 rhs :: { Located (GRHSs RdrName) }
1231 : '=' exp wherebinds { sL (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
1232 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
1234 gdrhs :: { Located [LGRHS RdrName] }
1235 : gdrhs gdrh { LL ($2 : unLoc $1) }
1238 gdrh :: { LGRHS RdrName }
1239 : '|' guardquals '=' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1241 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
1242 : infixexp '::' sigtypedoc
1243 {% do s <- checkValSig $1 $3;
1244 return (LL $ unitOL (LL $ SigD s)) }
1245 -- See the above notes for why we need infixexp here
1246 | var ',' sig_vars '::' sigtypedoc
1247 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
1248 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
1250 | '{-# INLINE' activation qvar '#-}'
1251 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 (getINLINE $1)))) }
1252 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1253 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1255 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1256 { LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 (getSPEC_INLINE $1)))
1258 | '{-# SPECIALISE' 'instance' inst_type '#-}'
1259 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1261 -----------------------------------------------------------------------------
1264 exp :: { LHsExpr RdrName }
1265 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1266 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1267 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1268 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1269 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1272 infixexp :: { LHsExpr RdrName }
1274 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1276 exp10 :: { LHsExpr RdrName }
1277 : '\\' apat apats opt_asig '->' exp
1278 { LL $ HsLam (mkMatchGroup [LL $ Match ($2:$3) $4
1281 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1282 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1283 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1284 | '-' fexp { LL $ NegApp $2 noSyntaxExpr }
1286 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1287 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1288 return (L loc (mkHsDo DoExpr stmts body)) }
1289 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1290 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1291 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1292 | scc_annot exp { LL $ if opt_SccProfilingOn
1293 then HsSCC (unLoc $1) $2
1295 | hpc_annot exp { LL $ if opt_Hpc
1296 then HsTickPragma (unLoc $1) $2
1299 | 'proc' aexp '->' exp
1300 {% checkPattern $2 >>= \ p ->
1301 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1302 placeHolderType undefined)) }
1303 -- TODO: is LL right here?
1305 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1306 -- hdaume: core annotation
1309 scc_annot :: { Located FastString }
1310 : '_scc_' STRING {% (addWarning Opt_WarnDeprecations (getLoc $1) (text "_scc_ is deprecated; use an SCC pragma instead")) >>= \_ ->
1311 (return $ LL $ getSTRING $2) }
1312 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1314 hpc_annot :: { Located (FastString,(Int,Int),(Int,Int)) }
1315 : '{-# GENERATED' STRING INTEGER ':' INTEGER '-' INTEGER ':' INTEGER '#-}'
1316 { LL $ (getSTRING $2
1317 ,( fromInteger $ getINTEGER $3
1318 , fromInteger $ getINTEGER $5
1320 ,( fromInteger $ getINTEGER $7
1321 , fromInteger $ getINTEGER $9
1326 fexp :: { LHsExpr RdrName }
1327 : fexp aexp { LL $ HsApp $1 $2 }
1330 aexp :: { LHsExpr RdrName }
1331 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1332 | '~' aexp { LL $ ELazyPat $2 }
1335 aexp1 :: { LHsExpr RdrName }
1336 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4) $3
1340 -- Here was the syntax for type applications that I was planning
1341 -- but there are difficulties (e.g. what order for type args)
1342 -- so it's not enabled yet.
1343 -- But this case *is* used for the left hand side of a generic definition,
1344 -- which is parsed as an expression before being munged into a pattern
1345 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1346 (sL (getLoc $3) (HsType $3)) }
1348 aexp2 :: { LHsExpr RdrName }
1349 : ipvar { L1 (HsIPVar $! unLoc $1) }
1350 | qcname { L1 (HsVar $! unLoc $1) }
1351 | literal { L1 (HsLit $! unLoc $1) }
1352 -- This will enable overloaded strings permanently. Normally the renamer turns HsString
1353 -- into HsOverLit when -foverloaded-strings is on.
1354 -- | STRING { sL (getLoc $1) (HsOverLit $! mkHsIsString (getSTRING $1) placeHolderType) }
1355 | INTEGER { sL (getLoc $1) (HsOverLit $! mkHsIntegral (getINTEGER $1) placeHolderType) }
1356 | RATIONAL { sL (getLoc $1) (HsOverLit $! mkHsFractional (getRATIONAL $1) placeHolderType) }
1357 -- N.B.: sections get parsed by these next two productions.
1358 -- This allows you to write, e.g., '(+ 3, 4 -)', which isn't correct Haskell98
1359 -- (you'd have to write '((+ 3), (4 -))')
1360 -- but the less cluttered version fell out of having texps.
1361 | '(' texp ')' { LL (HsPar $2) }
1362 | '(' texp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1363 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1364 | '[' list ']' { LL (unLoc $2) }
1365 | '[:' parr ':]' { LL (unLoc $2) }
1366 | '_' { L1 EWildPat }
1368 -- Template Haskell Extension
1369 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1370 (L1 $ HsVar (mkUnqual varName
1371 (getTH_ID_SPLICE $1)))) } -- $x
1372 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1374 | TH_QUASIQUOTE { let { loc = getLoc $1
1375 ; ITquasiQuote (quoter, quote, quoteSpan) = unLoc $1
1376 ; quoterId = mkUnqual varName quoter
1378 in sL loc $ HsQuasiQuoteE (mkHsQuasiQuote quoterId quoteSpan quote) }
1379 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1380 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1381 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1382 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1383 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1384 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1385 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1386 return (LL $ HsBracket (PatBr p)) }
1387 | '[d|' cvtopbody '|]' {% checkDecBrGroup $2 >>= \g ->
1388 return (LL $ HsBracket (DecBr g)) }
1390 -- arrow notation extension
1391 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1393 cmdargs :: { [LHsCmdTop RdrName] }
1394 : cmdargs acmd { $2 : $1 }
1395 | {- empty -} { [] }
1397 acmd :: { LHsCmdTop RdrName }
1398 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1400 cvtopbody :: { [LHsDecl RdrName] }
1401 : '{' cvtopdecls0 '}' { $2 }
1402 | vocurly cvtopdecls0 close { $2 }
1404 cvtopdecls0 :: { [LHsDecl RdrName] }
1405 : {- empty -} { [] }
1408 -- tuple expressions: things that can appear unparenthesized as long as they're
1409 -- inside parens or delimitted by commas
1410 texp :: { LHsExpr RdrName }
1412 -- Technically, this should only be used for bang patterns,
1413 -- but we can be a little more liberal here and avoid parens
1415 | infixexp qop { LL $ SectionL $1 $2 }
1416 | qopm infixexp { LL $ SectionR $1 $2 }
1417 -- view patterns get parenthesized above
1418 | exp '->' exp { LL $ EViewPat $1 $3 }
1420 texps :: { [LHsExpr RdrName] }
1421 : texps ',' texp { $3 : $1 }
1425 -----------------------------------------------------------------------------
1428 -- The rules below are little bit contorted to keep lexps left-recursive while
1429 -- avoiding another shift/reduce-conflict.
1431 list :: { LHsExpr RdrName }
1432 : texp { L1 $ ExplicitList placeHolderType [$1] }
1433 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1434 | texp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1435 | texp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1436 | texp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1437 | texp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1438 | texp '|' flattenedpquals { sL (comb2 $1 $>) $ mkHsDo ListComp (unLoc $3) $1 }
1440 lexps :: { Located [LHsExpr RdrName] }
1441 : lexps ',' texp { LL (((:) $! $3) $! unLoc $1) }
1442 | texp ',' texp { LL [$3,$1] }
1444 -----------------------------------------------------------------------------
1445 -- List Comprehensions
1447 flattenedpquals :: { Located [LStmt RdrName] }
1448 : pquals { case (unLoc $1) of
1449 ParStmt [(qs, _)] -> L1 qs
1450 -- We just had one thing in our "parallel" list so
1451 -- we simply return that thing directly
1454 -- We actually found some actual parallel lists so
1455 -- we leave them into as a ParStmt
1458 pquals :: { LStmt RdrName }
1459 : pquals1 { L1 (ParStmt [(qs, undefined) | qs <- (reverse (unLoc $1))]) }
1461 pquals1 :: { Located [[LStmt RdrName]] }
1462 : pquals1 '|' squals { LL (unLoc $3 : unLoc $1) }
1463 | squals { L (getLoc $1) [unLoc $1] }
1465 squals :: { Located [LStmt RdrName] }
1466 : squals1 { L (getLoc $1) (reverse (unLoc $1)) }
1468 squals1 :: { Located [LStmt RdrName] }
1469 : transformquals1 { LL (unLoc $1) }
1471 transformquals1 :: { Located [LStmt RdrName] }
1472 : transformquals1 ',' transformqual { LL $ [LL ((unLoc $3) (unLoc $1))] }
1473 | transformquals1 ',' qual { LL ($3 : unLoc $1) }
1474 -- | transformquals1 ',' '{|' pquals '|}' { LL ($4 : unLoc $1) }
1475 | transformqual { LL $ [LL ((unLoc $1) [])] }
1477 -- | '{|' pquals '|}' { L1 [$2] }
1480 -- It is possible to enable bracketing (associating) qualifier lists by uncommenting the lines with {| |}
1481 -- above. Due to a lack of consensus on the syntax, this feature is not being used until we get user
1482 -- demand. Note that the {| |} symbols are reused from -XGenerics and hence if you want to compile
1483 -- a program that makes use of this temporary syntax you must supply that flag to GHC
1485 transformqual :: { Located ([LStmt RdrName] -> Stmt RdrName) }
1486 : 'then' exp { LL $ \leftStmts -> (mkTransformStmt (reverse leftStmts) $2) }
1487 | 'then' exp 'by' exp { LL $ \leftStmts -> (mkTransformByStmt (reverse leftStmts) $2 $4) }
1488 | 'then' 'group' 'by' exp { LL $ \leftStmts -> (mkGroupByStmt (reverse leftStmts) $4) }
1489 | 'then' 'group' 'using' exp { LL $ \leftStmts -> (mkGroupUsingStmt (reverse leftStmts) $4) }
1490 | 'then' 'group' 'by' exp 'using' exp { LL $ \leftStmts -> (mkGroupByUsingStmt (reverse leftStmts) $4 $6) }
1492 -----------------------------------------------------------------------------
1493 -- Parallel array expressions
1495 -- The rules below are little bit contorted; see the list case for details.
1496 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1497 -- Moreover, we allow explicit arrays with no element (represented by the nil
1498 -- constructor in the list case).
1500 parr :: { LHsExpr RdrName }
1501 : { noLoc (ExplicitPArr placeHolderType []) }
1502 | texp { L1 $ ExplicitPArr placeHolderType [$1] }
1503 | lexps { L1 $ ExplicitPArr placeHolderType
1504 (reverse (unLoc $1)) }
1505 | texp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1506 | texp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1507 | texp '|' flattenedpquals { LL $ mkHsDo PArrComp (unLoc $3) $1 }
1509 -- We are reusing `lexps' and `flattenedpquals' from the list case.
1511 -----------------------------------------------------------------------------
1514 guardquals :: { Located [LStmt RdrName] }
1515 : guardquals1 { L (getLoc $1) (reverse (unLoc $1)) }
1517 guardquals1 :: { Located [LStmt RdrName] }
1518 : guardquals1 ',' qual { LL ($3 : unLoc $1) }
1521 -----------------------------------------------------------------------------
1522 -- Case alternatives
1524 altslist :: { Located [LMatch RdrName] }
1525 : '{' alts '}' { LL (reverse (unLoc $2)) }
1526 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1528 alts :: { Located [LMatch RdrName] }
1529 : alts1 { L1 (unLoc $1) }
1530 | ';' alts { LL (unLoc $2) }
1532 alts1 :: { Located [LMatch RdrName] }
1533 : alts1 ';' alt { LL ($3 : unLoc $1) }
1534 | alts1 ';' { LL (unLoc $1) }
1537 alt :: { LMatch RdrName }
1538 : pat opt_sig alt_rhs { LL (Match [$1] $2 (unLoc $3)) }
1540 alt_rhs :: { Located (GRHSs RdrName) }
1541 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1543 ralt :: { Located [LGRHS RdrName] }
1544 : '->' exp { LL (unguardedRHS $2) }
1545 | gdpats { L1 (reverse (unLoc $1)) }
1547 gdpats :: { Located [LGRHS RdrName] }
1548 : gdpats gdpat { LL ($2 : unLoc $1) }
1551 gdpat :: { LGRHS RdrName }
1552 : '|' guardquals '->' exp { sL (comb2 $1 $>) $ GRHS (unLoc $2) $4 }
1554 -- 'pat' recognises a pattern, including one with a bang at the top
1555 -- e.g. "!x" or "!(x,y)" or "C a b" etc
1556 -- Bangs inside are parsed as infix operator applications, so that
1557 -- we parse them right when bang-patterns are off
1558 pat :: { LPat RdrName }
1559 pat : exp {% checkPattern $1 }
1560 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1562 apat :: { LPat RdrName }
1563 apat : aexp {% checkPattern $1 }
1564 | '!' aexp {% checkPattern (LL (SectionR (L1 (HsVar bang_RDR)) $2)) }
1566 apats :: { [LPat RdrName] }
1567 : apat apats { $1 : $2 }
1568 | {- empty -} { [] }
1570 -----------------------------------------------------------------------------
1571 -- Statement sequences
1573 stmtlist :: { Located [LStmt RdrName] }
1574 : '{' stmts '}' { LL (unLoc $2) }
1575 | vocurly stmts close { $2 }
1577 -- do { ;; s ; s ; ; s ;; }
1578 -- The last Stmt should be an expression, but that's hard to enforce
1579 -- here, because we need too much lookahead if we see do { e ; }
1580 -- So we use ExprStmts throughout, and switch the last one over
1581 -- in ParseUtils.checkDo instead
1582 stmts :: { Located [LStmt RdrName] }
1583 : stmt stmts_help { LL ($1 : unLoc $2) }
1584 | ';' stmts { LL (unLoc $2) }
1585 | {- empty -} { noLoc [] }
1587 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1588 : ';' stmts { LL (unLoc $2) }
1589 | {- empty -} { noLoc [] }
1591 -- For typing stmts at the GHCi prompt, where
1592 -- the input may consist of just comments.
1593 maybe_stmt :: { Maybe (LStmt RdrName) }
1595 | {- nothing -} { Nothing }
1597 stmt :: { LStmt RdrName }
1599 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1601 qual :: { LStmt RdrName }
1602 : pat '<-' exp { LL $ mkBindStmt $1 $3 }
1603 | exp { L1 $ mkExprStmt $1 }
1604 | 'let' binds { LL $ LetStmt (unLoc $2) }
1606 -----------------------------------------------------------------------------
1607 -- Record Field Update/Construction
1609 fbinds :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1611 | {- empty -} { ([], False) }
1613 fbinds1 :: { ([HsRecField RdrName (LHsExpr RdrName)], Bool) }
1614 : fbind ',' fbinds1 { case $3 of (flds, dd) -> ($1 : flds, dd) }
1615 | fbind { ([$1], False) }
1616 | '..' { ([], True) }
1618 fbind :: { HsRecField RdrName (LHsExpr RdrName) }
1619 : qvar '=' exp { HsRecField $1 $3 False }
1620 | qvar { HsRecField $1 (L (getLoc $1) (HsVar (unLoc $1))) True }
1621 -- Here's where we say that plain 'x'
1622 -- means exactly 'x = x'. The pun-flag boolean is
1623 -- there so we can still print it right
1625 -----------------------------------------------------------------------------
1626 -- Implicit Parameter Bindings
1628 dbinds :: { Located [LIPBind RdrName] }
1629 : dbinds ';' dbind { let { this = $3; rest = unLoc $1 }
1630 in rest `seq` this `seq` LL (this : rest) }
1631 | dbinds ';' { LL (unLoc $1) }
1632 | dbind { let this = $1 in this `seq` L1 [this] }
1633 -- | {- empty -} { [] }
1635 dbind :: { LIPBind RdrName }
1636 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1638 ipvar :: { Located (IPName RdrName) }
1639 : IPDUPVARID { L1 (IPName (mkUnqual varName (getIPDUPVARID $1))) }
1641 -----------------------------------------------------------------------------
1644 depreclist :: { Located [RdrName] }
1645 depreclist : deprec_var { L1 [unLoc $1] }
1646 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1648 deprec_var :: { Located RdrName }
1649 deprec_var : var { $1 }
1652 -----------------------------------------
1653 -- Data constructors
1654 qcon :: { Located RdrName }
1656 | '(' qconsym ')' { LL (unLoc $2) }
1657 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1658 -- The case of '[:' ':]' is part of the production `parr'
1660 con :: { Located RdrName }
1662 | '(' consym ')' { LL (unLoc $2) }
1663 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1665 sysdcon :: { Located DataCon } -- Wired in data constructors
1666 : '(' ')' { LL unitDataCon }
1667 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1668 | '(#' '#)' { LL $ unboxedSingletonDataCon }
1669 | '(#' commas '#)' { LL $ tupleCon Unboxed $2 }
1670 | '[' ']' { LL nilDataCon }
1672 conop :: { Located RdrName }
1674 | '`' conid '`' { LL (unLoc $2) }
1676 qconop :: { Located RdrName }
1678 | '`' qconid '`' { LL (unLoc $2) }
1680 -----------------------------------------------------------------------------
1681 -- Type constructors
1683 gtycon :: { Located RdrName } -- A "general" qualified tycon
1685 | '(' ')' { LL $ getRdrName unitTyCon }
1686 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1687 | '(#' '#)' { LL $ getRdrName unboxedSingletonTyCon }
1688 | '(#' commas '#)' { LL $ getRdrName (tupleTyCon Unboxed $2) }
1689 | '(' '->' ')' { LL $ getRdrName funTyCon }
1690 | '[' ']' { LL $ listTyCon_RDR }
1691 | '[:' ':]' { LL $ parrTyCon_RDR }
1693 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1695 | '(' qtyconsym ')' { LL (unLoc $2) }
1697 qtyconop :: { Located RdrName } -- Qualified or unqualified
1699 | '`' qtycon '`' { LL (unLoc $2) }
1701 qtycon :: { Located RdrName } -- Qualified or unqualified
1702 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1705 tycon :: { Located RdrName } -- Unqualified
1706 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1708 qtyconsym :: { Located RdrName }
1709 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1712 tyconsym :: { Located RdrName }
1713 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1715 -----------------------------------------------------------------------------
1718 op :: { Located RdrName } -- used in infix decls
1722 varop :: { Located RdrName }
1724 | '`' varid '`' { LL (unLoc $2) }
1726 qop :: { LHsExpr RdrName } -- used in sections
1727 : qvarop { L1 $ HsVar (unLoc $1) }
1728 | qconop { L1 $ HsVar (unLoc $1) }
1730 qopm :: { LHsExpr RdrName } -- used in sections
1731 : qvaropm { L1 $ HsVar (unLoc $1) }
1732 | qconop { L1 $ HsVar (unLoc $1) }
1734 qvarop :: { Located RdrName }
1736 | '`' qvarid '`' { LL (unLoc $2) }
1738 qvaropm :: { Located RdrName }
1739 : qvarsym_no_minus { $1 }
1740 | '`' qvarid '`' { LL (unLoc $2) }
1742 -----------------------------------------------------------------------------
1745 tyvar :: { Located RdrName }
1746 tyvar : tyvarid { $1 }
1747 | '(' tyvarsym ')' { LL (unLoc $2) }
1749 tyvarop :: { Located RdrName }
1750 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1753 tyvarid :: { Located RdrName }
1754 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1755 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1756 | 'unsafe' { L1 $! mkUnqual tvName (fsLit "unsafe") }
1757 | 'safe' { L1 $! mkUnqual tvName (fsLit "safe") }
1758 | 'threadsafe' { L1 $! mkUnqual tvName (fsLit "threadsafe") }
1760 tyvarsym :: { Located RdrName }
1761 -- Does not include "!", because that is used for strictness marks
1762 -- or ".", because that separates the quantified type vars from the rest
1763 -- or "*", because that's used for kinds
1764 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1766 -----------------------------------------------------------------------------
1769 var :: { Located RdrName }
1771 | '(' varsym ')' { LL (unLoc $2) }
1773 qvar :: { Located RdrName }
1775 | '(' varsym ')' { LL (unLoc $2) }
1776 | '(' qvarsym1 ')' { LL (unLoc $2) }
1777 -- We've inlined qvarsym here so that the decision about
1778 -- whether it's a qvar or a var can be postponed until
1779 -- *after* we see the close paren.
1781 qvarid :: { Located RdrName }
1783 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1785 varid :: { Located RdrName }
1786 : varid_no_unsafe { $1 }
1787 | 'unsafe' { L1 $! mkUnqual varName (fsLit "unsafe") }
1788 | 'safe' { L1 $! mkUnqual varName (fsLit "safe") }
1789 | 'threadsafe' { L1 $! mkUnqual varName (fsLit "threadsafe") }
1791 varid_no_unsafe :: { Located RdrName }
1792 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1793 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1794 | 'forall' { L1 $! mkUnqual varName (fsLit "forall") }
1795 | 'family' { L1 $! mkUnqual varName (fsLit "family") }
1797 qvarsym :: { Located RdrName }
1801 qvarsym_no_minus :: { Located RdrName }
1802 : varsym_no_minus { $1 }
1805 qvarsym1 :: { Located RdrName }
1806 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1808 varsym :: { Located RdrName }
1809 : varsym_no_minus { $1 }
1810 | '-' { L1 $ mkUnqual varName (fsLit "-") }
1812 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1813 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1814 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1817 -- These special_ids are treated as keywords in various places,
1818 -- but as ordinary ids elsewhere. 'special_id' collects all these
1819 -- except 'unsafe', 'forall', and 'family' whose treatment differs
1820 -- depending on context
1821 special_id :: { Located FastString }
1823 : 'as' { L1 (fsLit "as") }
1824 | 'qualified' { L1 (fsLit "qualified") }
1825 | 'hiding' { L1 (fsLit "hiding") }
1826 | 'export' { L1 (fsLit "export") }
1827 | 'label' { L1 (fsLit "label") }
1828 | 'dynamic' { L1 (fsLit "dynamic") }
1829 | 'stdcall' { L1 (fsLit "stdcall") }
1830 | 'ccall' { L1 (fsLit "ccall") }
1832 special_sym :: { Located FastString }
1833 special_sym : '!' { L1 (fsLit "!") }
1834 | '.' { L1 (fsLit ".") }
1835 | '*' { L1 (fsLit "*") }
1837 -----------------------------------------------------------------------------
1838 -- Data constructors
1840 qconid :: { Located RdrName } -- Qualified or unqualified
1842 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1844 conid :: { Located RdrName }
1845 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1847 qconsym :: { Located RdrName } -- Qualified or unqualified
1849 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1851 consym :: { Located RdrName }
1852 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1854 -- ':' means only list cons
1855 | ':' { L1 $ consDataCon_RDR }
1858 -----------------------------------------------------------------------------
1861 literal :: { Located HsLit }
1862 : CHAR { L1 $ HsChar $ getCHAR $1 }
1863 | STRING { L1 $ HsString $ getSTRING $1 }
1864 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1865 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1866 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1867 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1868 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1870 -----------------------------------------------------------------------------
1874 : vccurly { () } -- context popped in lexer.
1875 | error {% popContext }
1877 -----------------------------------------------------------------------------
1878 -- Miscellaneous (mostly renamings)
1880 modid :: { Located ModuleName }
1881 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1882 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1885 (unpackFS mod ++ '.':unpackFS c))
1889 : commas ',' { $1 + 1 }
1892 -----------------------------------------------------------------------------
1893 -- Documentation comments
1895 docnext :: { LHsDoc RdrName }
1896 : DOCNEXT {% case parseHaddockParagraphs (tokenise (getDOCNEXT $1)) of {
1897 MyLeft err -> parseError (getLoc $1) err;
1898 MyRight doc -> return (L1 doc) } }
1900 docprev :: { LHsDoc RdrName }
1901 : DOCPREV {% case parseHaddockParagraphs (tokenise (getDOCPREV $1)) of {
1902 MyLeft err -> parseError (getLoc $1) err;
1903 MyRight doc -> return (L1 doc) } }
1905 docnamed :: { Located (String, (HsDoc RdrName)) }
1907 let string = getDOCNAMED $1
1908 (name, rest) = break isSpace string
1909 in case parseHaddockParagraphs (tokenise rest) of {
1910 MyLeft err -> parseError (getLoc $1) err;
1911 MyRight doc -> return (L1 (name, doc)) } }
1913 docsection :: { Located (Int, HsDoc RdrName) }
1914 : DOCSECTION {% let (n, doc) = getDOCSECTION $1 in
1915 case parseHaddockString (tokenise doc) of {
1916 MyLeft err -> parseError (getLoc $1) err;
1917 MyRight doc -> return (L1 (n, doc)) } }
1919 moduleheader :: { (HaddockModInfo RdrName, Maybe (HsDoc RdrName)) }
1920 : DOCNEXT {% let string = getDOCNEXT $1 in
1921 case parseModuleHeader string of {
1922 Right (str, info) ->
1923 case parseHaddockParagraphs (tokenise str) of {
1924 MyLeft err -> parseError (getLoc $1) err;
1925 MyRight doc -> return (info, Just doc);
1927 Left err -> parseError (getLoc $1) err
1930 maybe_docprev :: { Maybe (LHsDoc RdrName) }
1931 : docprev { Just $1 }
1932 | {- empty -} { Nothing }
1934 maybe_docnext :: { Maybe (LHsDoc RdrName) }
1935 : docnext { Just $1 }
1936 | {- empty -} { Nothing }
1940 happyError = srcParseFail
1942 getVARID (L _ (ITvarid x)) = x
1943 getCONID (L _ (ITconid x)) = x
1944 getVARSYM (L _ (ITvarsym x)) = x
1945 getCONSYM (L _ (ITconsym x)) = x
1946 getQVARID (L _ (ITqvarid x)) = x
1947 getQCONID (L _ (ITqconid x)) = x
1948 getQVARSYM (L _ (ITqvarsym x)) = x
1949 getQCONSYM (L _ (ITqconsym x)) = x
1950 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1951 getCHAR (L _ (ITchar x)) = x
1952 getSTRING (L _ (ITstring x)) = x
1953 getINTEGER (L _ (ITinteger x)) = x
1954 getRATIONAL (L _ (ITrational x)) = x
1955 getPRIMCHAR (L _ (ITprimchar x)) = x
1956 getPRIMSTRING (L _ (ITprimstring x)) = x
1957 getPRIMINTEGER (L _ (ITprimint x)) = x
1958 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1959 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1960 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1961 getINLINE (L _ (ITinline_prag b)) = b
1962 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
1964 getDOCNEXT (L _ (ITdocCommentNext x)) = x
1965 getDOCPREV (L _ (ITdocCommentPrev x)) = x
1966 getDOCNAMED (L _ (ITdocCommentNamed x)) = x
1967 getDOCSECTION (L _ (ITdocSection n x)) = (n, x)
1969 -- Utilities for combining source spans
1970 comb2 :: Located a -> Located b -> SrcSpan
1971 comb2 a b = a `seq` b `seq` combineLocs a b
1973 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1974 comb3 a b c = a `seq` b `seq` c `seq`
1975 combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1977 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1978 comb4 a b c d = a `seq` b `seq` c `seq` d `seq`
1979 (combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1980 combineSrcSpans (getLoc c) (getLoc d))
1982 -- strict constructor version:
1984 sL :: SrcSpan -> a -> Located a
1985 sL span a = span `seq` a `seq` L span a
1987 -- Make a source location for the file. We're a bit lazy here and just
1988 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1989 -- try to find the span of the whole file (ToDo).
1990 fileSrcSpan :: P SrcSpan
1993 let loc = mkSrcLoc (srcLocFile l) 1 0;
1994 return (mkSrcSpan loc loc)