2 -- ---------------------------------------------------------------------------
3 -- (c) The University of Glasgow 1997-2003
7 -- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
8 -- ---------------------------------------------------------------------------
11 module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
14 #define INCLUDE #include
15 INCLUDE "HsVersions.h"
19 import HscTypes ( IsBootInterface, DeprecTxt )
22 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
23 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
24 import Type ( funTyCon )
25 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
26 CCallConv(..), CCallTarget(..), defaultCCallConv
28 import OccName ( varName, dataName, tcClsName, tvName )
29 import DataCon ( DataCon, dataConName )
30 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
31 SrcSpan, combineLocs, srcLocFile,
34 import StaticFlags ( opt_SccProfilingOn )
35 import Type ( Kind, mkArrowKind, liftedTypeKind, unliftedTypeKind )
36 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
37 Activation(..), defaultInlineSpec )
41 import Maybes ( orElse )
47 -----------------------------------------------------------------------------
50 Conflicts: 37 shift/reduce
53 The reduce/reduce conflict is weird. It's between tyconsym and consym, and I
54 would think the two should never occur in the same context.
58 -----------------------------------------------------------------------------
59 Conflicts: 36 shift/reduce (1.25)
61 10 for abiguity in 'if x then y else z + 1' [State 178]
62 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
63 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
65 1 for ambiguity in 'if x then y else z :: T' [State 178]
66 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
68 4 for ambiguity in 'if x then y else z -< e' [State 178]
69 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
70 There are four such operators: -<, >-, -<<, >>-
73 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
74 Which of these two is intended?
76 (x::T) -> T -- Rhs is T
79 (x::T -> T) -> .. -- Rhs is ...
81 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
84 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
85 Same duplication between states 11 and 253 as the previous case
87 1 for ambiguity in 'let ?x ...' [State 329]
88 the parser can't tell whether the ?x is the lhs of a normal binding or
89 an implicit binding. Fortunately resolving as shift gives it the only
90 sensible meaning, namely the lhs of an implicit binding.
92 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
93 we don't know whether the '[' starts the activation or not: it
94 might be the start of the declaration with the activation being
97 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
98 since 'forall' is a valid variable name, we don't know whether
99 to treat a forall on the input as the beginning of a quantifier
100 or the beginning of the rule itself. Resolving to shift means
101 it's always treated as a quantifier, hence the above is disallowed.
102 This saves explicitly defining a grammar for the rule lhs that
103 doesn't include 'forall'.
105 -- ---------------------------------------------------------------------------
106 -- Adding location info
108 This is done in a stylised way using the three macros below, L0, L1
109 and LL. Each of these macros can be thought of as having type
111 L0, L1, LL :: a -> Located a
113 They each add a SrcSpan to their argument.
115 L0 adds 'noSrcSpan', used for empty productions
116 -- This doesn't seem to work anymore -=chak
118 L1 for a production with a single token on the lhs. Grabs the SrcSpan
121 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
122 the first and last tokens.
124 These suffice for the majority of cases. However, we must be
125 especially careful with empty productions: LL won't work if the first
126 or last token on the lhs can represent an empty span. In these cases,
127 we have to calculate the span using more of the tokens from the lhs, eg.
129 | 'newtype' tycl_hdr '=' newconstr deriving
131 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
133 We provide comb3 and comb4 functions which are useful in such cases.
135 Be careful: there's no checking that you actually got this right, the
136 only symptom will be that the SrcSpans of your syntax will be
140 * We must expand these macros *before* running Happy, which is why this file is
141 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
143 #define L0 L noSrcSpan
144 #define L1 sL (getLoc $1)
145 #define LL sL (comb2 $1 $>)
147 -- -----------------------------------------------------------------------------
152 '_' { L _ ITunderscore } -- Haskell keywords
154 'case' { L _ ITcase }
155 'class' { L _ ITclass }
156 'data' { L _ ITdata }
157 'default' { L _ ITdefault }
158 'deriving' { L _ ITderiving }
160 'else' { L _ ITelse }
161 'hiding' { L _ IThiding }
163 'import' { L _ ITimport }
165 'infix' { L _ ITinfix }
166 'infixl' { L _ ITinfixl }
167 'infixr' { L _ ITinfixr }
168 'instance' { L _ ITinstance }
170 'module' { L _ ITmodule }
171 'newtype' { L _ ITnewtype }
173 'qualified' { L _ ITqualified }
174 'then' { L _ ITthen }
175 'type' { L _ ITtype }
176 'where' { L _ ITwhere }
177 '_scc_' { L _ ITscc } -- ToDo: remove
179 'forall' { L _ ITforall } -- GHC extension keywords
180 'foreign' { L _ ITforeign }
181 'export' { L _ ITexport }
182 'label' { L _ ITlabel }
183 'dynamic' { L _ ITdynamic }
184 'safe' { L _ ITsafe }
185 'threadsafe' { L _ ITthreadsafe }
186 'unsafe' { L _ ITunsafe }
189 'stdcall' { L _ ITstdcallconv }
190 'ccall' { L _ ITccallconv }
191 'dotnet' { L _ ITdotnet }
192 'proc' { L _ ITproc } -- for arrow notation extension
193 'rec' { L _ ITrec } -- for arrow notation extension
195 '{-# INLINE' { L _ (ITinline_prag _) }
196 '{-# SPECIALISE' { L _ ITspec_prag }
197 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
198 '{-# SOURCE' { L _ ITsource_prag }
199 '{-# RULES' { L _ ITrules_prag }
200 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
201 '{-# SCC' { L _ ITscc_prag }
202 '{-# DEPRECATED' { L _ ITdeprecated_prag }
203 '{-# UNPACK' { L _ ITunpack_prag }
204 '#-}' { L _ ITclose_prag }
206 '..' { L _ ITdotdot } -- reserved symbols
208 '::' { L _ ITdcolon }
212 '<-' { L _ ITlarrow }
213 '->' { L _ ITrarrow }
216 '=>' { L _ ITdarrow }
220 '-<' { L _ ITlarrowtail } -- for arrow notation
221 '>-' { L _ ITrarrowtail } -- for arrow notation
222 '-<<' { L _ ITLarrowtail } -- for arrow notation
223 '>>-' { L _ ITRarrowtail } -- for arrow notation
226 '{' { L _ ITocurly } -- special symbols
228 '{|' { L _ ITocurlybar }
229 '|}' { L _ ITccurlybar }
230 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
231 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
234 '[:' { L _ ITopabrack }
235 ':]' { L _ ITcpabrack }
238 '(#' { L _ IToubxparen }
239 '#)' { L _ ITcubxparen }
240 '(|' { L _ IToparenbar }
241 '|)' { L _ ITcparenbar }
244 '`' { L _ ITbackquote }
246 VARID { L _ (ITvarid _) } -- identifiers
247 CONID { L _ (ITconid _) }
248 VARSYM { L _ (ITvarsym _) }
249 CONSYM { L _ (ITconsym _) }
250 QVARID { L _ (ITqvarid _) }
251 QCONID { L _ (ITqconid _) }
252 QVARSYM { L _ (ITqvarsym _) }
253 QCONSYM { L _ (ITqconsym _) }
255 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
256 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
258 CHAR { L _ (ITchar _) }
259 STRING { L _ (ITstring _) }
260 INTEGER { L _ (ITinteger _) }
261 RATIONAL { L _ (ITrational _) }
263 PRIMCHAR { L _ (ITprimchar _) }
264 PRIMSTRING { L _ (ITprimstring _) }
265 PRIMINTEGER { L _ (ITprimint _) }
266 PRIMFLOAT { L _ (ITprimfloat _) }
267 PRIMDOUBLE { L _ (ITprimdouble _) }
270 '[|' { L _ ITopenExpQuote }
271 '[p|' { L _ ITopenPatQuote }
272 '[t|' { L _ ITopenTypQuote }
273 '[d|' { L _ ITopenDecQuote }
274 '|]' { L _ ITcloseQuote }
275 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
276 '$(' { L _ ITparenEscape } -- $( exp )
277 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
278 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
280 %monad { P } { >>= } { return }
281 %lexer { lexer } { L _ ITeof }
282 %name parseModule module
283 %name parseStmt maybe_stmt
284 %name parseIdentifier identifier
285 %name parseType ctype
286 %partial parseHeader header
287 %tokentype { (Located Token) }
290 -----------------------------------------------------------------------------
291 -- Identifiers; one of the entry points
292 identifier :: { Located RdrName }
298 -----------------------------------------------------------------------------
301 -- The place for module deprecation is really too restrictive, but if it
302 -- was allowed at its natural place just before 'module', we get an ugly
303 -- s/r conflict with the second alternative. Another solution would be the
304 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
305 -- either, and DEPRECATED is only expected to be used by people who really
306 -- know what they are doing. :-)
308 module :: { Located (HsModule RdrName) }
309 : 'module' modid maybemoddeprec maybeexports 'where' body
310 {% fileSrcSpan >>= \ loc ->
311 return (L loc (HsModule (Just $2) $4 (fst $6) (snd $6) $3)) }
312 | missing_module_keyword top close
313 {% fileSrcSpan >>= \ loc ->
314 return (L loc (HsModule Nothing Nothing
315 (fst $2) (snd $2) Nothing)) }
317 missing_module_keyword :: { () }
318 : {- empty -} {% pushCurrentContext }
320 maybemoddeprec :: { Maybe DeprecTxt }
321 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
322 | {- empty -} { Nothing }
324 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
326 | vocurly top close { $2 }
328 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
329 : importdecls { (reverse $1,[]) }
330 | importdecls ';' cvtopdecls { (reverse $1,$3) }
331 | cvtopdecls { ([],$1) }
333 cvtopdecls :: { [LHsDecl RdrName] }
334 : topdecls { cvTopDecls $1 }
336 -----------------------------------------------------------------------------
337 -- Module declaration & imports only
339 header :: { Located (HsModule RdrName) }
340 : 'module' modid maybemoddeprec maybeexports 'where' header_body
341 {% fileSrcSpan >>= \ loc ->
342 return (L loc (HsModule (Just $2) $4 $6 [] $3)) }
343 | missing_module_keyword importdecls
344 {% fileSrcSpan >>= \ loc ->
345 return (L loc (HsModule Nothing Nothing $2 [] Nothing)) }
347 header_body :: { [LImportDecl RdrName] }
348 : '{' importdecls { $2 }
349 | vocurly importdecls { $2 }
351 -----------------------------------------------------------------------------
354 maybeexports :: { Maybe [LIE RdrName] }
355 : '(' exportlist ')' { Just $2 }
356 | {- empty -} { Nothing }
358 exportlist :: { [LIE RdrName] }
362 exportlist1 :: { [LIE RdrName] }
364 | export ',' exportlist { $1 : $3 }
367 -- No longer allow things like [] and (,,,) to be exported
368 -- They are built in syntax, always available
369 export :: { LIE RdrName }
370 : qvar { L1 (IEVar (unLoc $1)) }
371 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
372 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
373 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
374 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
375 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
377 qcnames :: { [RdrName] }
378 : qcnames ',' qcname { unLoc $3 : $1 }
379 | qcname { [unLoc $1] }
381 qcname :: { Located RdrName } -- Variable or data constructor
385 -----------------------------------------------------------------------------
386 -- Import Declarations
388 -- import decls can be *empty*, or even just a string of semicolons
389 -- whereas topdecls must contain at least one topdecl.
391 importdecls :: { [LImportDecl RdrName] }
392 : importdecls ';' importdecl { $3 : $1 }
393 | importdecls ';' { $1 }
394 | importdecl { [ $1 ] }
397 importdecl :: { LImportDecl RdrName }
398 : 'import' maybe_src optqualified modid maybeas maybeimpspec
399 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
401 maybe_src :: { IsBootInterface }
402 : '{-# SOURCE' '#-}' { True }
403 | {- empty -} { False }
405 optqualified :: { Bool }
406 : 'qualified' { True }
407 | {- empty -} { False }
409 maybeas :: { Located (Maybe ModuleName) }
410 : 'as' modid { LL (Just (unLoc $2)) }
411 | {- empty -} { noLoc Nothing }
413 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
414 : impspec { L1 (Just (unLoc $1)) }
415 | {- empty -} { noLoc Nothing }
417 impspec :: { Located (Bool, [LIE RdrName]) }
418 : '(' exportlist ')' { LL (False, $2) }
419 | 'hiding' '(' exportlist ')' { LL (True, $3) }
421 -----------------------------------------------------------------------------
422 -- Fixity Declarations
426 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
428 infix :: { Located FixityDirection }
429 : 'infix' { L1 InfixN }
430 | 'infixl' { L1 InfixL }
431 | 'infixr' { L1 InfixR }
433 ops :: { Located [Located RdrName] }
434 : ops ',' op { LL ($3 : unLoc $1) }
437 -----------------------------------------------------------------------------
438 -- Top-Level Declarations
440 topdecls :: { OrdList (LHsDecl RdrName) }
441 : topdecls ';' topdecl { $1 `appOL` $3 }
442 | topdecls ';' { $1 }
445 topdecl :: { OrdList (LHsDecl RdrName) }
446 : cl_decl { unitOL (L1 (TyClD (unLoc $1))) }
447 | ty_decl {% checkTopTyClD $1 >>= return.unitOL.L1 }
448 | 'instance' inst_type where
449 { let (binds, sigs, ats) = cvBindsAndSigs (unLoc $3)
450 in unitOL (L (comb3 $1 $2 $3)
451 (InstD (InstDecl $2 binds sigs ats))) }
452 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
453 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
454 | '{-# DEPRECATED' deprecations '#-}' { $2 }
455 | '{-# RULES' rules '#-}' { $2 }
458 -- Template Haskell Extension
459 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
460 | TH_ID_SPLICE { unitOL (LL $ SpliceD (SpliceDecl $
461 L1 $ HsVar (mkUnqual varName (getTH_ID_SPLICE $1))
466 cl_decl :: { LTyClDecl RdrName }
467 : 'class' tycl_hdr fds where
468 {% do { let { (binds, sigs, ats) =
469 cvBindsAndSigs (unLoc $4)
470 ; (ctxt, tc, tvs, Just tparms) = unLoc $2}
471 ; checkTyVars tparms False -- only type vars allowed
472 ; return $ L (comb4 $1 $2 $3 $4)
473 (mkClassDecl (ctxt, tc, tvs)
474 (unLoc $3) sigs binds ats) } }
478 ty_decl :: { LTyClDecl RdrName }
479 -- type function signature and equations (w/ type synonyms as special
480 -- case); we need to handle all this in one rule to avoid a large
481 -- number of shift/reduce conflicts (due to the generality of `type')
482 : 'type' opt_iso type kind_or_ctype
484 -- Note the use of type for the head; this allows
485 -- infix type constructors to be declared and type
486 -- patterns for type function equations
488 -- We have that `typats :: Maybe [LHsType name]' is `Nothing'
489 -- (in the second case alternative) when all arguments are
490 -- variables (and we thus have a vanilla type synonym
491 -- declaration); otherwise, it contains all arguments as type
496 do { (tc, tvs, _) <- checkSynHdr $3 False
497 ; return (L (comb3 $1 $3 kind)
498 (TyFunction tc tvs $2 (unLoc kind)))
501 do { (tc, tvs, typats) <- checkSynHdr $3 True
502 ; return (L (comb2 $1 ty)
503 (TySynonym tc tvs typats ty)) }
506 -- data type or newtype declaration
507 | data_or_newtype tycl_hdr constrs deriving
508 { L (comb4 $1 $2 $3 $4) -- We need the location on tycl_hdr
509 -- in case constrs and deriving are
511 (mkTyData (unLoc $1) (unLoc $2) Nothing
512 (reverse (unLoc $3)) (unLoc $4)) }
515 | data_or_newtype tycl_hdr opt_kind_sig
516 'where' gadt_constrlist
518 { L (comb4 $1 $2 $4 $5)
519 (mkTyData (unLoc $1) (unLoc $2) $3
520 (reverse (unLoc $5)) (unLoc $6)) }
526 kind_or_ctype :: { Either (Located (Maybe Kind)) (LHsType RdrName) }
527 : { Left (noLoc Nothing) }
528 | '::' kind { Left (LL (Just (unLoc $2))) }
529 | '=' ctype { Right (LL (unLoc $2)) }
530 -- Note ctype, not sigtype, on the right of '='
531 -- We allow an explicit for-all but we don't insert one
532 -- in type Foo a = (b,b)
533 -- Instead we just say b is out of scope
535 data_or_newtype :: { Located NewOrData }
536 : 'data' { L1 DataType }
537 | 'newtype' { L1 NewType }
539 opt_kind_sig :: { Maybe Kind }
541 | '::' kind { Just (unLoc $2) }
543 -- tycl_hdr parses the header of a type decl,
544 -- which takes the form
547 -- (Eq a, Ord b) => T a b
548 -- T Int [a] -- for associated types
549 -- Rather a lot of inlining here, else we get reduce/reduce errors
550 tycl_hdr :: { Located (LHsContext RdrName,
552 [LHsTyVarBndr RdrName],
553 Maybe [LHsType RdrName]) }
554 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
555 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
557 -----------------------------------------------------------------------------
558 -- Nested declarations
560 -- Type declaration or value declaration
562 tydecl :: { Located (OrdList (LHsDecl RdrName)) }
563 tydecl : ty_decl { LL (unitOL (L1 (TyClD (unLoc $1)))) }
566 tydecls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
567 : tydecls ';' tydecl { LL (unLoc $1 `appOL` unLoc $3) }
568 | tydecls ';' { LL (unLoc $1) }
570 | {- empty -} { noLoc nilOL }
574 :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
575 : '{' tydecls '}' { LL (unLoc $2) }
576 | vocurly tydecls close { $2 }
578 -- Form of the body of class and instance declarations
580 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
581 -- No implicit parameters
582 -- May have type declarations
583 : 'where' tydecllist { LL (unLoc $2) }
584 | {- empty -} { noLoc nilOL }
586 decls :: { Located (OrdList (LHsDecl RdrName)) }
587 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
588 | decls ';' { LL (unLoc $1) }
590 | {- empty -} { noLoc nilOL }
593 decllist :: { Located (OrdList (LHsDecl RdrName)) }
594 : '{' decls '}' { LL (unLoc $2) }
595 | vocurly decls close { $2 }
597 -- Binding groups other than those of class and instance declarations
599 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
600 -- No type declarations
601 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
602 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
603 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
605 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
606 -- No type declarations
607 : 'where' binds { LL (unLoc $2) }
608 | {- empty -} { noLoc emptyLocalBinds }
611 -----------------------------------------------------------------------------
612 -- Transformation Rules
614 rules :: { OrdList (LHsDecl RdrName) }
615 : rules ';' rule { $1 `snocOL` $3 }
618 | {- empty -} { nilOL }
620 rule :: { LHsDecl RdrName }
621 : STRING activation rule_forall infixexp '=' exp
622 { LL $ RuleD (HsRule (getSTRING $1)
623 ($2 `orElse` AlwaysActive)
624 $3 $4 placeHolderNames $6 placeHolderNames) }
626 activation :: { Maybe Activation }
627 : {- empty -} { Nothing }
628 | explicit_activation { Just $1 }
630 explicit_activation :: { Activation } -- In brackets
631 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
632 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
634 rule_forall :: { [RuleBndr RdrName] }
635 : 'forall' rule_var_list '.' { $2 }
638 rule_var_list :: { [RuleBndr RdrName] }
640 | rule_var rule_var_list { $1 : $2 }
642 rule_var :: { RuleBndr RdrName }
643 : varid { RuleBndr $1 }
644 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
646 -----------------------------------------------------------------------------
647 -- Deprecations (c.f. rules)
649 deprecations :: { OrdList (LHsDecl RdrName) }
650 : deprecations ';' deprecation { $1 `appOL` $3 }
651 | deprecations ';' { $1 }
653 | {- empty -} { nilOL }
655 -- SUP: TEMPORARY HACK, not checking for `module Foo'
656 deprecation :: { OrdList (LHsDecl RdrName) }
658 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
662 -----------------------------------------------------------------------------
663 -- Foreign import and export declarations
665 fdecl :: { LHsDecl RdrName }
666 fdecl : 'import' callconv safety fspec
667 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
668 | 'import' callconv fspec
669 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
671 | 'export' callconv fspec
672 {% mkExport $2 (unLoc $3) >>= return.LL }
674 callconv :: { CallConv }
675 : 'stdcall' { CCall StdCallConv }
676 | 'ccall' { CCall CCallConv }
677 | 'dotnet' { DNCall }
680 : 'unsafe' { PlayRisky }
681 | 'safe' { PlaySafe False }
682 | 'threadsafe' { PlaySafe True }
684 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
685 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
686 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
687 -- if the entity string is missing, it defaults to the empty string;
688 -- the meaning of an empty entity string depends on the calling
691 -----------------------------------------------------------------------------
694 opt_sig :: { Maybe (LHsType RdrName) }
695 : {- empty -} { Nothing }
696 | '::' sigtype { Just $2 }
698 opt_asig :: { Maybe (LHsType RdrName) }
699 : {- empty -} { Nothing }
700 | '::' atype { Just $2 }
702 sigtypes1 :: { [LHsType RdrName] }
704 | sigtype ',' sigtypes1 { $1 : $3 }
706 sigtype :: { LHsType RdrName }
707 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
708 -- Wrap an Implicit forall if there isn't one there already
710 sig_vars :: { Located [Located RdrName] }
711 : sig_vars ',' var { LL ($3 : unLoc $1) }
714 -----------------------------------------------------------------------------
717 strict_mark :: { Located HsBang }
718 : '!' { L1 HsStrict }
719 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
721 -- A ctype is a for-all type
722 ctype :: { LHsType RdrName }
723 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
724 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
725 -- A type of form (context => type) is an *implicit* HsForAllTy
728 -- We parse a context as a btype so that we don't get reduce/reduce
729 -- errors in ctype. The basic problem is that
731 -- looks so much like a tuple type. We can't tell until we find the =>
732 context :: { LHsContext RdrName }
733 : btype {% checkContext $1 }
735 type :: { LHsType RdrName }
736 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
739 gentype :: { LHsType RdrName }
741 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
742 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
743 | btype '->' ctype { LL $ HsFunTy $1 $3 }
745 btype :: { LHsType RdrName }
746 : btype atype { LL $ HsAppTy $1 $2 }
749 atype :: { LHsType RdrName }
750 : gtycon { L1 (HsTyVar (unLoc $1)) }
751 | tyvar { L1 (HsTyVar (unLoc $1)) }
752 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
753 | '(' ctype ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
754 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
755 | '[' ctype ']' { LL $ HsListTy $2 }
756 | '[:' ctype ':]' { LL $ HsPArrTy $2 }
757 | '(' ctype ')' { LL $ HsParTy $2 }
758 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 (unLoc $4) }
760 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
762 -- An inst_type is what occurs in the head of an instance decl
763 -- e.g. (Foo a, Gaz b) => Wibble a b
764 -- It's kept as a single type, with a MonoDictTy at the right
765 -- hand corner, for convenience.
766 inst_type :: { LHsType RdrName }
767 : sigtype {% checkInstType $1 }
769 inst_types1 :: { [LHsType RdrName] }
771 | inst_type ',' inst_types1 { $1 : $3 }
773 comma_types0 :: { [LHsType RdrName] }
774 : comma_types1 { $1 }
777 comma_types1 :: { [LHsType RdrName] }
779 | ctype ',' comma_types1 { $1 : $3 }
781 tv_bndrs :: { [LHsTyVarBndr RdrName] }
782 : tv_bndr tv_bndrs { $1 : $2 }
785 tv_bndr :: { LHsTyVarBndr RdrName }
786 : tyvar { L1 (UserTyVar (unLoc $1)) }
787 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2)
790 fds :: { Located [Located ([RdrName], [RdrName])] }
791 : {- empty -} { noLoc [] }
792 | '|' fds1 { LL (reverse (unLoc $2)) }
794 fds1 :: { Located [Located ([RdrName], [RdrName])] }
795 : fds1 ',' fd { LL ($3 : unLoc $1) }
798 fd :: { Located ([RdrName], [RdrName]) }
799 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
800 (reverse (unLoc $1), reverse (unLoc $3)) }
802 varids0 :: { Located [RdrName] }
803 : {- empty -} { noLoc [] }
804 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
806 -----------------------------------------------------------------------------
809 kind :: { Located Kind }
811 | akind '->' kind { LL (mkArrowKind (unLoc $1) (unLoc $3)) }
813 akind :: { Located Kind }
814 : '*' { L1 liftedTypeKind }
815 | '!' { L1 unliftedTypeKind }
816 | '(' kind ')' { LL (unLoc $2) }
819 -----------------------------------------------------------------------------
820 -- Datatype declarations
822 gadt_constrlist :: { Located [LConDecl RdrName] }
823 : '{' gadt_constrs '}' { LL (unLoc $2) }
824 | vocurly gadt_constrs close { $2 }
826 gadt_constrs :: { Located [LConDecl RdrName] }
827 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
828 | gadt_constrs ';' { $1 }
829 | gadt_constr { L1 [$1] }
831 -- We allow the following forms:
832 -- C :: Eq a => a -> T a
833 -- C :: forall a. Eq a => !a -> T a
834 -- D { x,y :: a } :: T a
835 -- forall a. Eq a => D { x,y :: a } :: T a
837 gadt_constr :: { LConDecl RdrName }
839 { LL (mkGadtDecl $1 $3) }
840 -- Syntax: Maybe merge the record stuff with the single-case above?
841 -- (to kill the mostly harmless reduce/reduce error)
842 -- XXX revisit audreyt
843 | constr_stuff_record '::' sigtype
844 { let (con,details) = unLoc $1 in
845 LL (ConDecl con Implicit [] (noLoc []) details (ResTyGADT $3)) }
847 | forall context '=>' constr_stuff_record '::' sigtype
848 { let (con,details) = unLoc $4 in
849 LL (ConDecl con Implicit (unLoc $1) $2 details (ResTyGADT $6)) }
850 | forall constr_stuff_record '::' sigtype
851 { let (con,details) = unLoc $2 in
852 LL (ConDecl con Implicit (unLoc $1) (noLoc []) details (ResTyGADT $4)) }
856 constrs :: { Located [LConDecl RdrName] }
857 : {- empty; a GHC extension -} { noLoc [] }
858 | '=' constrs1 { LL (unLoc $2) }
860 constrs1 :: { Located [LConDecl RdrName] }
861 : constrs1 '|' constr { LL ($3 : unLoc $1) }
864 constr :: { LConDecl RdrName }
865 : forall context '=>' constr_stuff
866 { let (con,details) = unLoc $4 in
867 LL (ConDecl con Explicit (unLoc $1) $2 details ResTyH98) }
868 | forall constr_stuff
869 { let (con,details) = unLoc $2 in
870 LL (ConDecl con Explicit (unLoc $1) (noLoc []) details ResTyH98) }
872 forall :: { Located [LHsTyVarBndr RdrName] }
873 : 'forall' tv_bndrs '.' { LL $2 }
874 | {- empty -} { noLoc [] }
876 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
877 -- We parse the constructor declaration
879 -- as a btype (treating C as a type constructor) and then convert C to be
880 -- a data constructor. Reason: it might continue like this:
882 -- in which case C really would be a type constructor. We can't resolve this
883 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
884 : btype {% mkPrefixCon $1 [] >>= return.LL }
885 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
886 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
887 | btype conop btype { LL ($2, InfixCon $1 $3) }
889 constr_stuff_record :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
890 : oqtycon '{' '}' {% mkRecCon $1 [] >>= return.sL (comb2 $1 $>) }
891 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.sL (comb2 $1 $>) }
893 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
894 : fielddecl ',' fielddecls { unLoc $1 : $3 }
895 | fielddecl { [unLoc $1] }
897 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
898 : sig_vars '::' ctype { LL (reverse (unLoc $1), $3) }
900 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
901 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
902 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
903 -- We don't allow a context, but that's sorted out by the type checker.
904 deriving :: { Located (Maybe [LHsType RdrName]) }
905 : {- empty -} { noLoc Nothing }
906 | 'deriving' qtycon {% do { let { L loc tv = $2 }
907 ; p <- checkInstType (L loc (HsTyVar tv))
908 ; return (LL (Just [p])) } }
909 | 'deriving' '(' ')' { LL (Just []) }
910 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
911 -- Glasgow extension: allow partial
912 -- applications in derivings
914 -----------------------------------------------------------------------------
917 {- There's an awkward overlap with a type signature. Consider
918 f :: Int -> Int = ...rhs...
919 Then we can't tell whether it's a type signature or a value
920 definition with a result signature until we see the '='.
921 So we have to inline enough to postpone reductions until we know.
925 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
926 instead of qvar, we get another shift/reduce-conflict. Consider the
929 { (^^) :: Int->Int ; } Type signature; only var allowed
931 { (^^) :: Int->Int = ... ; } Value defn with result signature;
932 qvar allowed (because of instance decls)
934 We can't tell whether to reduce var to qvar until after we've read the signatures.
937 decl :: { Located (OrdList (LHsDecl RdrName)) }
939 | '!' infixexp rhs {% do { pat <- checkPattern $2;
940 return (LL $ unitOL $ LL $ ValD $
941 PatBind (LL $ BangPat pat) (unLoc $3)
942 placeHolderType placeHolderNames) } }
943 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
944 return (LL $ unitOL (LL $ ValD r)) } }
946 rhs :: { Located (GRHSs RdrName) }
947 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
948 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
950 gdrhs :: { Located [LGRHS RdrName] }
951 : gdrhs gdrh { LL ($2 : unLoc $1) }
954 gdrh :: { LGRHS RdrName }
955 : '|' quals '=' exp { sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
957 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
958 : infixexp '::' sigtype
959 {% do s <- checkValSig $1 $3;
960 return (LL $ unitOL (LL $ SigD s)) }
961 -- See the above notes for why we need infixexp here
962 | var ',' sig_vars '::' sigtype
963 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
964 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
966 | '{-# INLINE' activation qvar '#-}'
967 { LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 (getINLINE $1)))) }
968 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
969 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
971 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
972 { LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 (getSPEC_INLINE $1)))
974 | '{-# SPECIALISE' 'instance' inst_type '#-}'
975 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
977 -----------------------------------------------------------------------------
980 exp :: { LHsExpr RdrName }
981 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
982 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
983 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
984 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
985 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
988 infixexp :: { LHsExpr RdrName }
990 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
992 exp10 :: { LHsExpr RdrName }
993 : '\\' aexp aexps opt_asig '->' exp
994 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
995 return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
996 (GRHSs (unguardedRHS $6) emptyLocalBinds
998 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
999 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1000 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1001 | '-' fexp { LL $ mkHsNegApp $2 }
1003 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1004 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1005 return (L loc (mkHsDo DoExpr stmts body)) }
1006 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1007 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1008 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1009 | scc_annot exp { LL $ if opt_SccProfilingOn
1010 then HsSCC (unLoc $1) $2
1013 | 'proc' aexp '->' exp
1014 {% checkPattern $2 >>= \ p ->
1015 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1016 placeHolderType undefined)) }
1017 -- TODO: is LL right here?
1019 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1020 -- hdaume: core annotation
1023 scc_annot :: { Located FastString }
1024 : '_scc_' STRING { LL $ getSTRING $2 }
1025 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1027 fexp :: { LHsExpr RdrName }
1028 : fexp aexp { LL $ HsApp $1 $2 }
1031 aexps :: { [LHsExpr RdrName] }
1032 : aexps aexp { $2 : $1 }
1033 | {- empty -} { [] }
1035 aexp :: { LHsExpr RdrName }
1036 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1037 | '~' aexp { LL $ ELazyPat $2 }
1038 -- | '!' aexp { LL $ EBangPat $2 }
1041 aexp1 :: { LHsExpr RdrName }
1042 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1047 -- Here was the syntax for type applications that I was planning
1048 -- but there are difficulties (e.g. what order for type args)
1049 -- so it's not enabled yet.
1050 -- But this case *is* used for the left hand side of a generic definition,
1051 -- which is parsed as an expression before being munged into a pattern
1052 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1053 (sL (getLoc $3) (HsType $3)) }
1055 aexp2 :: { LHsExpr RdrName }
1056 : ipvar { L1 (HsIPVar $! unLoc $1) }
1057 | qcname { L1 (HsVar $! unLoc $1) }
1058 | literal { L1 (HsLit $! unLoc $1) }
1059 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1060 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1061 | '(' exp ')' { LL (HsPar $2) }
1062 | '(' texp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1063 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1064 | '[' list ']' { LL (unLoc $2) }
1065 | '[:' parr ':]' { LL (unLoc $2) }
1066 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1067 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1068 | '_' { L1 EWildPat }
1070 -- Template Haskell Extension
1071 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1072 (L1 $ HsVar (mkUnqual varName
1073 (getTH_ID_SPLICE $1)))) } -- $x
1074 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1076 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1077 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1078 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1079 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1080 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1081 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1082 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1083 return (LL $ HsBracket (PatBr p)) }
1084 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1086 -- arrow notation extension
1087 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1089 cmdargs :: { [LHsCmdTop RdrName] }
1090 : cmdargs acmd { $2 : $1 }
1091 | {- empty -} { [] }
1093 acmd :: { LHsCmdTop RdrName }
1094 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1096 cvtopbody :: { [LHsDecl RdrName] }
1097 : '{' cvtopdecls0 '}' { $2 }
1098 | vocurly cvtopdecls0 close { $2 }
1100 cvtopdecls0 :: { [LHsDecl RdrName] }
1101 : {- empty -} { [] }
1104 texp :: { LHsExpr RdrName }
1106 | qopm infixexp { LL $ SectionR $1 $2 }
1107 -- The second production is really here only for bang patterns
1110 texps :: { [LHsExpr RdrName] }
1111 : texps ',' texp { $3 : $1 }
1115 -----------------------------------------------------------------------------
1118 -- The rules below are little bit contorted to keep lexps left-recursive while
1119 -- avoiding another shift/reduce-conflict.
1121 list :: { LHsExpr RdrName }
1122 : texp { L1 $ ExplicitList placeHolderType [$1] }
1123 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1124 | texp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1125 | texp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1126 | texp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1127 | texp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1128 | texp pquals { sL (comb2 $1 $>) $ mkHsDo ListComp (reverse (unLoc $2)) $1 }
1130 lexps :: { Located [LHsExpr RdrName] }
1131 : lexps ',' texp { LL ($3 : unLoc $1) }
1132 | texp ',' texp { LL [$3,$1] }
1134 -----------------------------------------------------------------------------
1135 -- List Comprehensions
1137 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1138 -- or a reversed list of Stmts
1139 : pquals1 { case unLoc $1 of
1141 qss -> L1 [L1 (ParStmt stmtss)]
1143 stmtss = [ (reverse qs, undefined)
1147 pquals1 :: { Located [[LStmt RdrName]] }
1148 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1149 | '|' quals { L (getLoc $2) [unLoc $2] }
1151 quals :: { Located [LStmt RdrName] }
1152 : quals ',' qual { LL ($3 : unLoc $1) }
1155 -----------------------------------------------------------------------------
1156 -- Parallel array expressions
1158 -- The rules below are little bit contorted; see the list case for details.
1159 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1160 -- Moreover, we allow explicit arrays with no element (represented by the nil
1161 -- constructor in the list case).
1163 parr :: { LHsExpr RdrName }
1164 : { noLoc (ExplicitPArr placeHolderType []) }
1165 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1166 | lexps { L1 $ ExplicitPArr placeHolderType
1167 (reverse (unLoc $1)) }
1168 | exp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1169 | exp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1170 | exp pquals { sL (comb2 $1 $>) $ mkHsDo PArrComp (reverse (unLoc $2)) $1 }
1172 -- We are reusing `lexps' and `pquals' from the list case.
1174 -----------------------------------------------------------------------------
1175 -- Case alternatives
1177 altslist :: { Located [LMatch RdrName] }
1178 : '{' alts '}' { LL (reverse (unLoc $2)) }
1179 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1181 alts :: { Located [LMatch RdrName] }
1182 : alts1 { L1 (unLoc $1) }
1183 | ';' alts { LL (unLoc $2) }
1185 alts1 :: { Located [LMatch RdrName] }
1186 : alts1 ';' alt { LL ($3 : unLoc $1) }
1187 | alts1 ';' { LL (unLoc $1) }
1190 alt :: { LMatch RdrName }
1191 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1192 return (LL (Match [p] $2 (unLoc $3))) }
1193 | '!' infixexp opt_sig alt_rhs {% checkPattern $2 >>= \p ->
1194 return (LL (Match [LL $ BangPat p] $3 (unLoc $4))) }
1196 alt_rhs :: { Located (GRHSs RdrName) }
1197 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1199 ralt :: { Located [LGRHS RdrName] }
1200 : '->' exp { LL (unguardedRHS $2) }
1201 | gdpats { L1 (reverse (unLoc $1)) }
1203 gdpats :: { Located [LGRHS RdrName] }
1204 : gdpats gdpat { LL ($2 : unLoc $1) }
1207 gdpat :: { LGRHS RdrName }
1208 : '|' quals '->' exp { sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
1210 -----------------------------------------------------------------------------
1211 -- Statement sequences
1213 stmtlist :: { Located [LStmt RdrName] }
1214 : '{' stmts '}' { LL (unLoc $2) }
1215 | vocurly stmts close { $2 }
1217 -- do { ;; s ; s ; ; s ;; }
1218 -- The last Stmt should be an expression, but that's hard to enforce
1219 -- here, because we need too much lookahead if we see do { e ; }
1220 -- So we use ExprStmts throughout, and switch the last one over
1221 -- in ParseUtils.checkDo instead
1222 stmts :: { Located [LStmt RdrName] }
1223 : stmt stmts_help { LL ($1 : unLoc $2) }
1224 | ';' stmts { LL (unLoc $2) }
1225 | {- empty -} { noLoc [] }
1227 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1228 : ';' stmts { LL (unLoc $2) }
1229 | {- empty -} { noLoc [] }
1231 -- For typing stmts at the GHCi prompt, where
1232 -- the input may consist of just comments.
1233 maybe_stmt :: { Maybe (LStmt RdrName) }
1235 | {- nothing -} { Nothing }
1237 stmt :: { LStmt RdrName }
1239 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1240 return (LL $ mkBindStmt p $1) }
1241 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1243 qual :: { LStmt RdrName }
1244 : exp '<-' exp {% checkPattern $1 >>= \p ->
1245 return (LL $ mkBindStmt p $3) }
1246 | exp { L1 $ mkExprStmt $1 }
1247 | 'let' binds { LL $ LetStmt (unLoc $2) }
1249 -----------------------------------------------------------------------------
1250 -- Record Field Update/Construction
1252 fbinds :: { HsRecordBinds RdrName }
1254 | {- empty -} { [] }
1256 fbinds1 :: { HsRecordBinds RdrName }
1257 : fbinds1 ',' fbind { $3 : $1 }
1260 fbind :: { (Located RdrName, LHsExpr RdrName) }
1261 : qvar '=' exp { ($1,$3) }
1263 -----------------------------------------------------------------------------
1264 -- Implicit Parameter Bindings
1266 dbinds :: { Located [LIPBind RdrName] }
1267 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1268 | dbinds ';' { LL (unLoc $1) }
1270 -- | {- empty -} { [] }
1272 dbind :: { LIPBind RdrName }
1273 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1275 ipvar :: { Located (IPName RdrName) }
1276 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1277 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1279 -----------------------------------------------------------------------------
1282 depreclist :: { Located [RdrName] }
1283 depreclist : deprec_var { L1 [unLoc $1] }
1284 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1286 deprec_var :: { Located RdrName }
1287 deprec_var : var { $1 }
1290 -----------------------------------------
1291 -- Data constructors
1292 qcon :: { Located RdrName }
1294 | '(' qconsym ')' { LL (unLoc $2) }
1295 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1296 -- The case of '[:' ':]' is part of the production `parr'
1298 con :: { Located RdrName }
1300 | '(' consym ')' { LL (unLoc $2) }
1301 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1303 sysdcon :: { Located DataCon } -- Wired in data constructors
1304 : '(' ')' { LL unitDataCon }
1305 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1306 | '[' ']' { LL nilDataCon }
1308 conop :: { Located RdrName }
1310 | '`' conid '`' { LL (unLoc $2) }
1312 qconop :: { Located RdrName }
1314 | '`' qconid '`' { LL (unLoc $2) }
1316 -----------------------------------------------------------------------------
1317 -- Type constructors
1319 gtycon :: { Located RdrName } -- A "general" qualified tycon
1321 | '(' ')' { LL $ getRdrName unitTyCon }
1322 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1323 | '(' '->' ')' { LL $ getRdrName funTyCon }
1324 | '[' ']' { LL $ listTyCon_RDR }
1325 | '[:' ':]' { LL $ parrTyCon_RDR }
1327 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1329 | '(' qtyconsym ')' { LL (unLoc $2) }
1331 qtyconop :: { Located RdrName } -- Qualified or unqualified
1333 | '`' qtycon '`' { LL (unLoc $2) }
1335 qtycon :: { Located RdrName } -- Qualified or unqualified
1336 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1339 tycon :: { Located RdrName } -- Unqualified
1340 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1342 qtyconsym :: { Located RdrName }
1343 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1346 tyconsym :: { Located RdrName }
1347 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1349 -----------------------------------------------------------------------------
1352 op :: { Located RdrName } -- used in infix decls
1356 varop :: { Located RdrName }
1358 | '`' varid '`' { LL (unLoc $2) }
1360 qop :: { LHsExpr RdrName } -- used in sections
1361 : qvarop { L1 $ HsVar (unLoc $1) }
1362 | qconop { L1 $ HsVar (unLoc $1) }
1364 qopm :: { LHsExpr RdrName } -- used in sections
1365 : qvaropm { L1 $ HsVar (unLoc $1) }
1366 | qconop { L1 $ HsVar (unLoc $1) }
1368 qvarop :: { Located RdrName }
1370 | '`' qvarid '`' { LL (unLoc $2) }
1372 qvaropm :: { Located RdrName }
1373 : qvarsym_no_minus { $1 }
1374 | '`' qvarid '`' { LL (unLoc $2) }
1376 -----------------------------------------------------------------------------
1379 tyvar :: { Located RdrName }
1380 tyvar : tyvarid { $1 }
1381 | '(' tyvarsym ')' { LL (unLoc $2) }
1383 tyvarop :: { Located RdrName }
1384 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1387 tyvarid :: { Located RdrName }
1388 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1389 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1390 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1391 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1392 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1394 tyvarsym :: { Located RdrName }
1395 -- Does not include "!", because that is used for strictness marks
1396 -- or ".", because that separates the quantified type vars from the rest
1397 -- or "*", because that's used for kinds
1398 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1400 -----------------------------------------------------------------------------
1403 var :: { Located RdrName }
1405 | '(' varsym ')' { LL (unLoc $2) }
1407 qvar :: { Located RdrName }
1409 | '(' varsym ')' { LL (unLoc $2) }
1410 | '(' qvarsym1 ')' { LL (unLoc $2) }
1411 -- We've inlined qvarsym here so that the decision about
1412 -- whether it's a qvar or a var can be postponed until
1413 -- *after* we see the close paren.
1415 qvarid :: { Located RdrName }
1417 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1419 varid :: { Located RdrName }
1420 : varid_no_unsafe { $1 }
1421 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1422 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1423 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1425 varid_no_unsafe :: { Located RdrName }
1426 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1427 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1428 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1430 qvarsym :: { Located RdrName }
1434 qvarsym_no_minus :: { Located RdrName }
1435 : varsym_no_minus { $1 }
1438 qvarsym1 :: { Located RdrName }
1439 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1441 varsym :: { Located RdrName }
1442 : varsym_no_minus { $1 }
1443 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1445 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1446 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1447 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1450 -- These special_ids are treated as keywords in various places,
1451 -- but as ordinary ids elsewhere. 'special_id' collects all these
1452 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1453 special_id :: { Located FastString }
1455 : 'as' { L1 FSLIT("as") }
1456 | 'qualified' { L1 FSLIT("qualified") }
1457 | 'hiding' { L1 FSLIT("hiding") }
1458 | 'export' { L1 FSLIT("export") }
1459 | 'label' { L1 FSLIT("label") }
1460 | 'dynamic' { L1 FSLIT("dynamic") }
1461 | 'stdcall' { L1 FSLIT("stdcall") }
1462 | 'ccall' { L1 FSLIT("ccall") }
1463 | 'iso' { L1 FSLIT("iso") }
1465 special_sym :: { Located FastString }
1466 special_sym : '!' { L1 FSLIT("!") }
1467 | '.' { L1 FSLIT(".") }
1468 | '*' { L1 FSLIT("*") }
1470 -----------------------------------------------------------------------------
1471 -- Data constructors
1473 qconid :: { Located RdrName } -- Qualified or unqualified
1475 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1477 conid :: { Located RdrName }
1478 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1480 qconsym :: { Located RdrName } -- Qualified or unqualified
1482 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1484 consym :: { Located RdrName }
1485 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1487 -- ':' means only list cons
1488 | ':' { L1 $ consDataCon_RDR }
1491 -----------------------------------------------------------------------------
1494 literal :: { Located HsLit }
1495 : CHAR { L1 $ HsChar $ getCHAR $1 }
1496 | STRING { L1 $ HsString $ getSTRING $1 }
1497 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1498 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1499 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1500 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1501 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1503 -----------------------------------------------------------------------------
1507 : vccurly { () } -- context popped in lexer.
1508 | error {% popContext }
1510 -----------------------------------------------------------------------------
1511 -- Miscellaneous (mostly renamings)
1513 modid :: { Located ModuleName }
1514 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1515 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1518 (unpackFS mod ++ '.':unpackFS c))
1522 : commas ',' { $1 + 1 }
1525 -----------------------------------------------------------------------------
1529 happyError = srcParseFail
1531 getVARID (L _ (ITvarid x)) = x
1532 getCONID (L _ (ITconid x)) = x
1533 getVARSYM (L _ (ITvarsym x)) = x
1534 getCONSYM (L _ (ITconsym x)) = x
1535 getQVARID (L _ (ITqvarid x)) = x
1536 getQCONID (L _ (ITqconid x)) = x
1537 getQVARSYM (L _ (ITqvarsym x)) = x
1538 getQCONSYM (L _ (ITqconsym x)) = x
1539 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1540 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1541 getCHAR (L _ (ITchar x)) = x
1542 getSTRING (L _ (ITstring x)) = x
1543 getINTEGER (L _ (ITinteger x)) = x
1544 getRATIONAL (L _ (ITrational x)) = x
1545 getPRIMCHAR (L _ (ITprimchar x)) = x
1546 getPRIMSTRING (L _ (ITprimstring x)) = x
1547 getPRIMINTEGER (L _ (ITprimint x)) = x
1548 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1549 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1550 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1551 getINLINE (L _ (ITinline_prag b)) = b
1552 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
1554 -- Utilities for combining source spans
1555 comb2 :: Located a -> Located b -> SrcSpan
1558 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1559 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1561 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1562 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1563 combineSrcSpans (getLoc c) (getLoc d)
1565 -- strict constructor version:
1567 sL :: SrcSpan -> a -> Located a
1568 sL span a = span `seq` L span a
1570 -- Make a source location for the file. We're a bit lazy here and just
1571 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1572 -- try to find the span of the whole file (ToDo).
1573 fileSrcSpan :: P SrcSpan
1576 let loc = mkSrcLoc (srcLocFile l) 1 0;
1577 return (mkSrcSpan loc loc)