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 ( UserFS, 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 )
36 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
37 Activation(..), InlineSpec(..), defaultInlineSpec )
42 import Maybes ( orElse )
48 -----------------------------------------------------------------------------
49 Conflicts: 36 shift/reduce (1.25)
51 10 for abiguity in 'if x then y else z + 1' [State 178]
52 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
53 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
55 1 for ambiguity in 'if x then y else z :: T' [State 178]
56 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
58 4 for ambiguity in 'if x then y else z -< e' [State 178]
59 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
60 There are four such operators: -<, >-, -<<, >>-
63 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
64 Which of these two is intended?
66 (x::T) -> T -- Rhs is T
69 (x::T -> T) -> .. -- Rhs is ...
71 10 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
74 As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
75 Same duplication between states 11 and 253 as the previous case
77 1 for ambiguity in 'let ?x ...' [State 329]
78 the parser can't tell whether the ?x is the lhs of a normal binding or
79 an implicit binding. Fortunately resolving as shift gives it the only
80 sensible meaning, namely the lhs of an implicit binding.
82 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
83 we don't know whether the '[' starts the activation or not: it
84 might be the start of the declaration with the activation being
87 6 for conflicts between `fdecl' and `fdeclDEPRECATED', [States 393,394]
88 which are resolved correctly, and moreover,
89 should go away when `fdeclDEPRECATED' is removed.
91 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
92 since 'forall' is a valid variable name, we don't know whether
93 to treat a forall on the input as the beginning of a quantifier
94 or the beginning of the rule itself. Resolving to shift means
95 it's always treated as a quantifier, hence the above is disallowed.
96 This saves explicitly defining a grammar for the rule lhs that
97 doesn't include 'forall'.
99 -- ---------------------------------------------------------------------------
100 -- Adding location info
102 This is done in a stylised way using the three macros below, L0, L1
103 and LL. Each of these macros can be thought of as having type
105 L0, L1, LL :: a -> Located a
107 They each add a SrcSpan to their argument.
109 L0 adds 'noSrcSpan', used for empty productions
111 L1 for a production with a single token on the lhs. Grabs the SrcSpan
114 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
115 the first and last tokens.
117 These suffice for the majority of cases. However, we must be
118 especially careful with empty productions: LL won't work if the first
119 or last token on the lhs can represent an empty span. In these cases,
120 we have to calculate the span using more of the tokens from the lhs, eg.
122 | 'newtype' tycl_hdr '=' newconstr deriving
124 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
126 We provide comb3 and comb4 functions which are useful in such cases.
128 Be careful: there's no checking that you actually got this right, the
129 only symptom will be that the SrcSpans of your syntax will be
133 * We must expand these macros *before* running Happy, which is why this file is
134 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
136 #define L0 L noSrcSpan
137 #define L1 sL (getLoc $1)
138 #define LL sL (comb2 $1 $>)
140 -- -----------------------------------------------------------------------------
145 '_' { L _ ITunderscore } -- Haskell keywords
147 'case' { L _ ITcase }
148 'class' { L _ ITclass }
149 'data' { L _ ITdata }
150 'default' { L _ ITdefault }
151 'deriving' { L _ ITderiving }
153 'else' { L _ ITelse }
154 'hiding' { L _ IThiding }
156 'import' { L _ ITimport }
158 'infix' { L _ ITinfix }
159 'infixl' { L _ ITinfixl }
160 'infixr' { L _ ITinfixr }
161 'instance' { L _ ITinstance }
163 'module' { L _ ITmodule }
164 'newtype' { L _ ITnewtype }
166 'qualified' { L _ ITqualified }
167 'then' { L _ ITthen }
168 'type' { L _ ITtype }
169 'where' { L _ ITwhere }
170 '_scc_' { L _ ITscc } -- ToDo: remove
172 'forall' { L _ ITforall } -- GHC extension keywords
173 'foreign' { L _ ITforeign }
174 'export' { L _ ITexport }
175 'label' { L _ ITlabel }
176 'dynamic' { L _ ITdynamic }
177 'safe' { L _ ITsafe }
178 'threadsafe' { L _ ITthreadsafe }
179 'unsafe' { L _ ITunsafe }
181 'stdcall' { L _ ITstdcallconv }
182 'ccall' { L _ ITccallconv }
183 'dotnet' { L _ ITdotnet }
184 'proc' { L _ ITproc } -- for arrow notation extension
185 'rec' { L _ ITrec } -- for arrow notation extension
187 '{-# INLINE' { L _ (ITinline_prag _) }
188 '{-# SPECIALISE' { L _ ITspec_prag }
189 '{-# SPECIALISE_INLINE' { L _ (ITspec_inline_prag _) }
190 '{-# SOURCE' { L _ ITsource_prag }
191 '{-# RULES' { L _ ITrules_prag }
192 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
193 '{-# SCC' { L _ ITscc_prag }
194 '{-# DEPRECATED' { L _ ITdeprecated_prag }
195 '{-# UNPACK' { L _ ITunpack_prag }
196 '#-}' { L _ ITclose_prag }
198 '..' { L _ ITdotdot } -- reserved symbols
200 '::' { L _ ITdcolon }
204 '<-' { L _ ITlarrow }
205 '->' { L _ ITrarrow }
208 '=>' { L _ ITdarrow }
212 '-<' { L _ ITlarrowtail } -- for arrow notation
213 '>-' { L _ ITrarrowtail } -- for arrow notation
214 '-<<' { L _ ITLarrowtail } -- for arrow notation
215 '>>-' { L _ ITRarrowtail } -- for arrow notation
218 '{' { L _ ITocurly } -- special symbols
220 '{|' { L _ ITocurlybar }
221 '|}' { L _ ITccurlybar }
222 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
223 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
226 '[:' { L _ ITopabrack }
227 ':]' { L _ ITcpabrack }
230 '(#' { L _ IToubxparen }
231 '#)' { L _ ITcubxparen }
232 '(|' { L _ IToparenbar }
233 '|)' { L _ ITcparenbar }
236 '`' { L _ ITbackquote }
238 VARID { L _ (ITvarid _) } -- identifiers
239 CONID { L _ (ITconid _) }
240 VARSYM { L _ (ITvarsym _) }
241 CONSYM { L _ (ITconsym _) }
242 QVARID { L _ (ITqvarid _) }
243 QCONID { L _ (ITqconid _) }
244 QVARSYM { L _ (ITqvarsym _) }
245 QCONSYM { L _ (ITqconsym _) }
247 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
248 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
250 CHAR { L _ (ITchar _) }
251 STRING { L _ (ITstring _) }
252 INTEGER { L _ (ITinteger _) }
253 RATIONAL { L _ (ITrational _) }
255 PRIMCHAR { L _ (ITprimchar _) }
256 PRIMSTRING { L _ (ITprimstring _) }
257 PRIMINTEGER { L _ (ITprimint _) }
258 PRIMFLOAT { L _ (ITprimfloat _) }
259 PRIMDOUBLE { L _ (ITprimdouble _) }
262 '[|' { L _ ITopenExpQuote }
263 '[p|' { L _ ITopenPatQuote }
264 '[t|' { L _ ITopenTypQuote }
265 '[d|' { L _ ITopenDecQuote }
266 '|]' { L _ ITcloseQuote }
267 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
268 '$(' { L _ ITparenEscape } -- $( exp )
269 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
270 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
272 %monad { P } { >>= } { return }
273 %lexer { lexer } { L _ ITeof }
274 %name parseModule module
275 %name parseStmt maybe_stmt
276 %name parseIdentifier identifier
277 %name parseType ctype
278 %partial parseHeader header
279 %tokentype { Located Token }
282 -----------------------------------------------------------------------------
283 -- Identifiers; one of the entry points
284 identifier :: { Located RdrName }
290 -----------------------------------------------------------------------------
293 -- The place for module deprecation is really too restrictive, but if it
294 -- was allowed at its natural place just before 'module', we get an ugly
295 -- s/r conflict with the second alternative. Another solution would be the
296 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
297 -- either, and DEPRECATED is only expected to be used by people who really
298 -- know what they are doing. :-)
300 module :: { Located (HsModule RdrName) }
301 : 'module' modid maybemoddeprec maybeexports 'where' body
302 {% fileSrcSpan >>= \ loc ->
303 return (L loc (HsModule (Just $2) $4 (fst $6) (snd $6) $3)) }
304 | missing_module_keyword top close
305 {% fileSrcSpan >>= \ loc ->
306 return (L loc (HsModule Nothing Nothing
307 (fst $2) (snd $2) Nothing)) }
309 missing_module_keyword :: { () }
310 : {- empty -} {% pushCurrentContext }
312 maybemoddeprec :: { Maybe DeprecTxt }
313 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
314 | {- empty -} { Nothing }
316 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
318 | vocurly top close { $2 }
320 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
321 : importdecls { (reverse $1,[]) }
322 | importdecls ';' cvtopdecls { (reverse $1,$3) }
323 | cvtopdecls { ([],$1) }
325 cvtopdecls :: { [LHsDecl RdrName] }
326 : topdecls { cvTopDecls $1 }
328 -----------------------------------------------------------------------------
329 -- Module declaration & imports only
331 header :: { Located (HsModule RdrName) }
332 : 'module' modid maybemoddeprec maybeexports 'where' header_body
333 {% fileSrcSpan >>= \ loc ->
334 return (L loc (HsModule (Just $2) $4 $6 [] $3)) }
335 | missing_module_keyword importdecls
336 {% fileSrcSpan >>= \ loc ->
337 return (L loc (HsModule Nothing Nothing $2 [] Nothing)) }
339 header_body :: { [LImportDecl RdrName] }
340 : '{' importdecls { $2 }
341 | vocurly importdecls { $2 }
343 -----------------------------------------------------------------------------
346 maybeexports :: { Maybe [LIE RdrName] }
347 : '(' exportlist ')' { Just $2 }
348 | {- empty -} { Nothing }
350 exportlist :: { [LIE RdrName] }
351 : exportlist ',' export { $3 : $1 }
352 | exportlist ',' { $1 }
356 -- No longer allow things like [] and (,,,) to be exported
357 -- They are built in syntax, always available
358 export :: { LIE RdrName }
359 : qvar { L1 (IEVar (unLoc $1)) }
360 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
361 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
362 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
363 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
364 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
366 qcnames :: { [RdrName] }
367 : qcnames ',' qcname { unLoc $3 : $1 }
368 | qcname { [unLoc $1] }
370 qcname :: { Located RdrName } -- Variable or data constructor
374 -----------------------------------------------------------------------------
375 -- Import Declarations
377 -- import decls can be *empty*, or even just a string of semicolons
378 -- whereas topdecls must contain at least one topdecl.
380 importdecls :: { [LImportDecl RdrName] }
381 : importdecls ';' importdecl { $3 : $1 }
382 | importdecls ';' { $1 }
383 | importdecl { [ $1 ] }
386 importdecl :: { LImportDecl RdrName }
387 : 'import' maybe_src optqualified modid maybeas maybeimpspec
388 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
390 maybe_src :: { IsBootInterface }
391 : '{-# SOURCE' '#-}' { True }
392 | {- empty -} { False }
394 optqualified :: { Bool }
395 : 'qualified' { True }
396 | {- empty -} { False }
398 maybeas :: { Located (Maybe Module) }
399 : 'as' modid { LL (Just (unLoc $2)) }
400 | {- empty -} { noLoc Nothing }
402 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
403 : impspec { L1 (Just (unLoc $1)) }
404 | {- empty -} { noLoc Nothing }
406 impspec :: { Located (Bool, [LIE RdrName]) }
407 : '(' exportlist ')' { LL (False, reverse $2) }
408 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
410 -----------------------------------------------------------------------------
411 -- Fixity Declarations
415 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
417 infix :: { Located FixityDirection }
418 : 'infix' { L1 InfixN }
419 | 'infixl' { L1 InfixL }
420 | 'infixr' { L1 InfixR }
422 ops :: { Located [Located RdrName] }
423 : ops ',' op { LL ($3 : unLoc $1) }
426 -----------------------------------------------------------------------------
427 -- Top-Level Declarations
429 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
430 : topdecls ';' topdecl { $1 `appOL` $3 }
431 | topdecls ';' { $1 }
434 topdecl :: { OrdList (LHsDecl RdrName) }
435 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
436 | 'instance' inst_type where
437 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
438 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
439 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
440 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
441 | '{-# DEPRECATED' deprecations '#-}' { $2 }
442 | '{-# RULES' rules '#-}' { $2 }
443 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
446 tycl_decl :: { LTyClDecl RdrName }
447 : 'type' type '=' ctype
448 -- Note type on the left of the '='; this allows
449 -- infix type constructors to be declared
451 -- Note ctype, not sigtype, on the right
452 -- We allow an explicit for-all but we don't insert one
453 -- in type Foo a = (b,b)
454 -- Instead we just say b is out of scope
455 {% do { (tc,tvs) <- checkSynHdr $2
456 ; return (LL (TySynonym tc tvs $4)) } }
458 | 'data' tycl_hdr constrs deriving
459 { L (comb4 $1 $2 $3 $4) -- We need the location on tycl_hdr
460 -- in case constrs and deriving are both empty
461 (mkTyData DataType $2 Nothing (reverse (unLoc $3)) (unLoc $4)) }
463 | 'data' tycl_hdr opt_kind_sig
464 'where' gadt_constrlist
466 { L (comb4 $1 $2 $4 $5)
467 (mkTyData DataType $2 $3 (reverse (unLoc $5)) (unLoc $6)) }
469 | 'newtype' tycl_hdr '=' newconstr deriving
471 (mkTyData NewType $2 Nothing [$4] (unLoc $5)) }
473 | 'class' tycl_hdr fds where
475 (binds,sigs) = cvBindsAndSigs (unLoc $4)
477 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
480 opt_kind_sig :: { Maybe Kind }
482 | '::' kind { Just $2 }
484 -- tycl_hdr parses the header of a type or class decl,
485 -- which takes the form
488 -- (Eq a, Ord b) => T a b
489 -- Rather a lot of inlining here, else we get reduce/reduce errors
490 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
491 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
492 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
494 -----------------------------------------------------------------------------
495 -- Nested declarations
497 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
498 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
499 | decls ';' { LL (unLoc $1) }
501 | {- empty -} { noLoc nilOL }
504 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
505 : '{' decls '}' { LL (unLoc $2) }
506 | vocurly decls close { $2 }
508 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
509 -- No implicit parameters
510 : 'where' decllist { LL (unLoc $2) }
511 | {- empty -} { noLoc nilOL }
513 binds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
514 : decllist { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
515 | '{' dbinds '}' { LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
516 | vocurly dbinds close { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
518 wherebinds :: { Located (HsLocalBinds RdrName) } -- May have implicit parameters
519 : 'where' binds { LL (unLoc $2) }
520 | {- empty -} { noLoc emptyLocalBinds }
523 -----------------------------------------------------------------------------
524 -- Transformation Rules
526 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
527 : rules ';' rule { $1 `snocOL` $3 }
530 | {- empty -} { nilOL }
532 rule :: { LHsDecl RdrName }
533 : STRING activation rule_forall infixexp '=' exp
534 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
536 activation :: { Activation } -- Omitted means AlwaysActive
537 : {- empty -} { AlwaysActive }
538 | explicit_activation { $1 }
540 explicit_activation :: { Activation } -- In brackets
541 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
542 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
544 rule_forall :: { [RuleBndr RdrName] }
545 : 'forall' rule_var_list '.' { $2 }
548 rule_var_list :: { [RuleBndr RdrName] }
550 | rule_var rule_var_list { $1 : $2 }
552 rule_var :: { RuleBndr RdrName }
553 : varid { RuleBndr $1 }
554 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
556 -----------------------------------------------------------------------------
557 -- Deprecations (c.f. rules)
559 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
560 : deprecations ';' deprecation { $1 `appOL` $3 }
561 | deprecations ';' { $1 }
563 | {- empty -} { nilOL }
565 -- SUP: TEMPORARY HACK, not checking for `module Foo'
566 deprecation :: { OrdList (LHsDecl RdrName) }
568 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
572 -----------------------------------------------------------------------------
573 -- Foreign import and export declarations
575 -- for the time being, the following accepts foreign declarations conforming
576 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
578 -- * a flag indicates whether pre-standard declarations have been used and
579 -- triggers a deprecation warning further down the road
581 -- NB: The first two rules could be combined into one by replacing `safety1'
582 -- with `safety'. However, the combined rule conflicts with the
585 fdecl :: { LHsDecl RdrName }
586 fdecl : 'import' callconv safety1 fspec
587 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
588 | 'import' callconv fspec
589 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
591 | 'export' callconv fspec
592 {% mkExport $2 (unLoc $3) >>= return.LL }
593 -- the following syntax is DEPRECATED
594 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
595 | fdecl2DEPRECATED { L1 (unLoc $1) }
597 fdecl1DEPRECATED :: { LForeignDecl RdrName }
599 ----------- DEPRECATED label decls ------------
600 : 'label' ext_name varid '::' sigtype
601 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
602 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
604 ----------- DEPRECATED ccall/stdcall decls ------------
606 -- NB: This business with the case expression below may seem overly
607 -- complicated, but it is necessary to avoid some conflicts.
609 -- DEPRECATED variant #1: lack of a calling convention specification
611 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
613 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
615 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
616 (CFunction target)) True }
618 -- DEPRECATED variant #2: external name consists of two separate strings
619 -- (module name and function name) (import)
620 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
622 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
623 CCall cconv -> return $
625 imp = CFunction (StaticTarget (getSTRING $4))
627 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
629 -- DEPRECATED variant #3: `unsafe' after entity
630 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
632 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
633 CCall cconv -> return $
635 imp = CFunction (StaticTarget (getSTRING $3))
637 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
639 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
640 -- an explicit calling convention (import)
641 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
642 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
643 (CFunction DynamicTarget)) True }
645 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
646 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
648 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
649 CCall cconv -> return $
650 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
651 (CFunction DynamicTarget)) True }
653 -- DEPRECATED variant #6: lack of a calling convention specification
655 | 'export' {-no callconv-} ext_name varid '::' sigtype
656 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
657 defaultCCallConv)) True }
659 -- DEPRECATED variant #7: external name consists of two separate strings
660 -- (module name and function name) (export)
661 | 'export' callconv STRING STRING varid '::' sigtype
663 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
664 CCall cconv -> return $
665 LL $ ForeignExport $5 $7
666 (CExport (CExportStatic (getSTRING $4) cconv)) True }
668 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
669 -- an explicit calling convention (export)
670 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
671 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
674 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
675 | 'export' callconv 'dynamic' varid '::' sigtype
677 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
678 CCall cconv -> return $
679 LL $ ForeignImport $4 $6
680 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
682 ----------- DEPRECATED .NET decls ------------
683 -- NB: removed the .NET call declaration, as it is entirely subsumed
684 -- by the new standard FFI declarations
686 fdecl2DEPRECATED :: { LHsDecl RdrName }
688 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
689 -- left this one unchanged for the moment as type imports are not
690 -- covered currently by the FFI standard -=chak
693 callconv :: { CallConv }
694 : 'stdcall' { CCall StdCallConv }
695 | 'ccall' { CCall CCallConv }
696 | 'dotnet' { DNCall }
699 : 'unsafe' { PlayRisky }
700 | 'safe' { PlaySafe False }
701 | 'threadsafe' { PlaySafe True }
702 | {- empty -} { PlaySafe False }
704 safety1 :: { Safety }
705 : 'unsafe' { PlayRisky }
706 | 'safe' { PlaySafe False }
707 | 'threadsafe' { PlaySafe True }
708 -- only needed to avoid conflicts with the DEPRECATED rules
710 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
711 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
712 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
713 -- if the entity string is missing, it defaults to the empty string;
714 -- the meaning of an empty entity string depends on the calling
718 ext_name :: { Maybe CLabelString }
719 : STRING { Just (getSTRING $1) }
720 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
721 | {- empty -} { Nothing }
724 -----------------------------------------------------------------------------
727 opt_sig :: { Maybe (LHsType RdrName) }
728 : {- empty -} { Nothing }
729 | '::' sigtype { Just $2 }
731 opt_asig :: { Maybe (LHsType RdrName) }
732 : {- empty -} { Nothing }
733 | '::' atype { Just $2 }
735 sigtypes1 :: { [LHsType RdrName] }
737 | sigtype ',' sigtypes1 { $1 : $3 }
739 sigtype :: { LHsType RdrName }
740 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
741 -- Wrap an Implicit forall if there isn't one there already
743 sig_vars :: { Located [Located RdrName] }
744 : sig_vars ',' var { LL ($3 : unLoc $1) }
747 -----------------------------------------------------------------------------
750 strict_mark :: { Located HsBang }
751 : '!' { L1 HsStrict }
752 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
754 -- A ctype is a for-all type
755 ctype :: { LHsType RdrName }
756 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
757 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
758 -- A type of form (context => type) is an *implicit* HsForAllTy
761 -- We parse a context as a btype so that we don't get reduce/reduce
762 -- errors in ctype. The basic problem is that
764 -- looks so much like a tuple type. We can't tell until we find the =>
765 context :: { LHsContext RdrName }
766 : btype {% checkContext $1 }
768 type :: { LHsType RdrName }
769 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
772 gentype :: { LHsType RdrName }
774 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
775 | btype tyvarop gentype { LL $ HsOpTy $1 $2 $3 }
776 | btype '->' gentype { LL $ HsFunTy $1 $3 }
778 btype :: { LHsType RdrName }
779 : btype atype { LL $ HsAppTy $1 $2 }
782 atype :: { LHsType RdrName }
783 : gtycon { L1 (HsTyVar (unLoc $1)) }
784 | tyvar { L1 (HsTyVar (unLoc $1)) }
785 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
786 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
787 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
788 | '[' type ']' { LL $ HsListTy $2 }
789 | '[:' type ':]' { LL $ HsPArrTy $2 }
790 | '(' ctype ')' { LL $ HsParTy $2 }
791 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
793 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
795 -- An inst_type is what occurs in the head of an instance decl
796 -- e.g. (Foo a, Gaz b) => Wibble a b
797 -- It's kept as a single type, with a MonoDictTy at the right
798 -- hand corner, for convenience.
799 inst_type :: { LHsType RdrName }
800 : sigtype {% checkInstType $1 }
802 inst_types1 :: { [LHsType RdrName] }
804 | inst_type ',' inst_types1 { $1 : $3 }
806 comma_types0 :: { [LHsType RdrName] }
807 : comma_types1 { $1 }
810 comma_types1 :: { [LHsType RdrName] }
812 | type ',' comma_types1 { $1 : $3 }
814 tv_bndrs :: { [LHsTyVarBndr RdrName] }
815 : tv_bndr tv_bndrs { $1 : $2 }
818 tv_bndr :: { LHsTyVarBndr RdrName }
819 : tyvar { L1 (UserTyVar (unLoc $1)) }
820 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
822 fds :: { Located [Located ([RdrName], [RdrName])] }
823 : {- empty -} { noLoc [] }
824 | '|' fds1 { LL (reverse (unLoc $2)) }
826 fds1 :: { Located [Located ([RdrName], [RdrName])] }
827 : fds1 ',' fd { LL ($3 : unLoc $1) }
830 fd :: { Located ([RdrName], [RdrName]) }
831 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
832 (reverse (unLoc $1), reverse (unLoc $3)) }
834 varids0 :: { Located [RdrName] }
835 : {- empty -} { noLoc [] }
836 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
838 -----------------------------------------------------------------------------
843 | akind '->' kind { mkArrowKind $1 $3 }
846 : '*' { liftedTypeKind }
847 | '(' kind ')' { $2 }
850 -----------------------------------------------------------------------------
851 -- Datatype declarations
853 newconstr :: { LConDecl RdrName }
854 : conid atype { LL $ ConDecl $1 Explicit [] (noLoc []) (PrefixCon [$2]) ResTyH98 }
855 | conid '{' var '::' ctype '}'
856 { LL $ ConDecl $1 Explicit [] (noLoc []) (RecCon [($3, $5)]) ResTyH98 }
858 gadt_constrlist :: { Located [LConDecl RdrName] }
859 : '{' gadt_constrs '}' { LL (unLoc $2) }
860 | vocurly gadt_constrs close { $2 }
862 gadt_constrs :: { Located [LConDecl RdrName] }
863 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
864 | gadt_constrs ';' { $1 }
865 | gadt_constr { L1 [$1] }
867 -- We allow the following forms:
868 -- C :: Eq a => a -> T a
869 -- C :: forall a. Eq a => !a -> T a
870 -- D { x,y :: a } :: T a
871 -- forall a. Eq a => D { x,y :: a } :: T a
873 gadt_constr :: { LConDecl RdrName }
875 { LL (mkGadtDecl $1 $3) }
876 -- Syntax: Maybe merge the record stuff with the single-case above?
877 -- (to kill the mostly harmless reduce/reduce error)
878 -- XXX revisit autrijus
879 | constr_stuff_record '::' sigtype
880 { let (con,details) = unLoc $1 in
881 LL (ConDecl con Implicit [] (noLoc []) details (ResTyGADT $3)) }
883 | forall context '=>' constr_stuff_record '::' sigtype
884 { let (con,details) = unLoc $4 in
885 LL (ConDecl con Implicit (unLoc $1) $2 details (ResTyGADT $6)) }
886 | forall constr_stuff_record '::' sigtype
887 { let (con,details) = unLoc $2 in
888 LL (ConDecl con Implicit (unLoc $1) (noLoc []) details (ResTyGADT $4)) }
892 constrs :: { Located [LConDecl RdrName] }
893 : {- empty; a GHC extension -} { noLoc [] }
894 | '=' constrs1 { LL (unLoc $2) }
896 constrs1 :: { Located [LConDecl RdrName] }
897 : constrs1 '|' constr { LL ($3 : unLoc $1) }
900 constr :: { LConDecl RdrName }
901 : forall context '=>' constr_stuff
902 { let (con,details) = unLoc $4 in
903 LL (ConDecl con Explicit (unLoc $1) $2 details ResTyH98) }
904 | forall constr_stuff
905 { let (con,details) = unLoc $2 in
906 LL (ConDecl con Explicit (unLoc $1) (noLoc []) details ResTyH98) }
908 forall :: { Located [LHsTyVarBndr RdrName] }
909 : 'forall' tv_bndrs '.' { LL $2 }
910 | {- empty -} { noLoc [] }
912 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
913 -- We parse the constructor declaration
915 -- as a btype (treating C as a type constructor) and then convert C to be
916 -- a data constructor. Reason: it might continue like this:
918 -- in which case C really would be a type constructor. We can't resolve this
919 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
920 : btype {% mkPrefixCon $1 [] >>= return.LL }
921 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
922 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
923 | btype conop btype { LL ($2, InfixCon $1 $3) }
925 constr_stuff_record :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
926 : oqtycon '{' '}' {% mkRecCon $1 [] >>= return.sL (comb2 $1 $>) }
927 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.sL (comb2 $1 $>) }
929 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
930 : fielddecl ',' fielddecls { unLoc $1 : $3 }
931 | fielddecl { [unLoc $1] }
933 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
934 : sig_vars '::' ctype { LL (reverse (unLoc $1), $3) }
936 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
937 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
938 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
939 -- We don't allow a context, but that's sorted out by the type checker.
940 deriving :: { Located (Maybe [LHsType RdrName]) }
941 : {- empty -} { noLoc Nothing }
942 | 'deriving' qtycon {% do { let { L loc tv = $2 }
943 ; p <- checkInstType (L loc (HsTyVar tv))
944 ; return (LL (Just [p])) } }
945 | 'deriving' '(' ')' { LL (Just []) }
946 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
947 -- Glasgow extension: allow partial
948 -- applications in derivings
950 -----------------------------------------------------------------------------
953 {- There's an awkward overlap with a type signature. Consider
954 f :: Int -> Int = ...rhs...
955 Then we can't tell whether it's a type signature or a value
956 definition with a result signature until we see the '='.
957 So we have to inline enough to postpone reductions until we know.
961 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
962 instead of qvar, we get another shift/reduce-conflict. Consider the
965 { (^^) :: Int->Int ; } Type signature; only var allowed
967 { (^^) :: Int->Int = ... ; } Value defn with result signature;
968 qvar allowed (because of instance decls)
970 We can't tell whether to reduce var to qvar until after we've read the signatures.
973 decl :: { Located (OrdList (LHsDecl RdrName)) }
975 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
976 return (LL $ unitOL (LL $ ValD r)) } }
978 rhs :: { Located (GRHSs RdrName) }
979 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
980 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
982 gdrhs :: { Located [LGRHS RdrName] }
983 : gdrhs gdrh { LL ($2 : unLoc $1) }
986 gdrh :: { LGRHS RdrName }
987 : '|' quals '=' exp { sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
989 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
990 : infixexp '::' sigtype
991 {% do s <- checkValSig $1 $3;
992 return (LL $ unitOL (LL $ SigD s)) }
993 -- See the above notes for why we need infixexp here
994 | var ',' sig_vars '::' sigtype
995 { LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
996 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
998 | '{-# INLINE' activation qvar '#-}'
999 { LL $ unitOL (LL $ SigD (InlineSig $3 (Inline $2 (getINLINE $1)))) }
1000 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1001 { LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1003 | '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1004 { LL $ toOL [ LL $ SigD (SpecSig $3 t (Inline $2 (getSPEC_INLINE $1)))
1006 | '{-# SPECIALISE' 'instance' inst_type '#-}'
1007 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1009 -----------------------------------------------------------------------------
1012 exp :: { LHsExpr RdrName }
1013 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1014 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1015 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1016 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1017 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1020 infixexp :: { LHsExpr RdrName }
1022 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1024 exp10 :: { LHsExpr RdrName }
1025 : '\\' aexp aexps opt_asig '->' exp
1026 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
1027 return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
1028 (GRHSs (unguardedRHS $6) emptyLocalBinds
1030 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1031 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1032 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1033 | '-' fexp { LL $ mkHsNegApp $2 }
1035 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1036 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1037 return (L loc (mkHsDo DoExpr stmts body)) }
1038 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1039 checkDo loc (unLoc $2) >>= \ (stmts,body) ->
1040 return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1041 | scc_annot exp { LL $ if opt_SccProfilingOn
1042 then HsSCC (unLoc $1) $2
1045 | 'proc' aexp '->' exp
1046 {% checkPattern $2 >>= \ p ->
1047 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1048 placeHolderType undefined)) }
1049 -- TODO: is LL right here?
1051 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1052 -- hdaume: core annotation
1055 scc_annot :: { Located FastString }
1056 : '_scc_' STRING { LL $ getSTRING $2 }
1057 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1059 fexp :: { LHsExpr RdrName }
1060 : fexp aexp { LL $ HsApp $1 $2 }
1063 aexps :: { [LHsExpr RdrName] }
1064 : aexps aexp { $2 : $1 }
1065 | {- empty -} { [] }
1067 aexp :: { LHsExpr RdrName }
1068 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1069 | '~' aexp { LL $ ELazyPat $2 }
1072 aexp1 :: { LHsExpr RdrName }
1073 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1078 -- Here was the syntax for type applications that I was planning
1079 -- but there are difficulties (e.g. what order for type args)
1080 -- so it's not enabled yet.
1081 -- But this case *is* used for the left hand side of a generic definition,
1082 -- which is parsed as an expression before being munged into a pattern
1083 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1084 (sL (getLoc $3) (HsType $3)) }
1086 aexp2 :: { LHsExpr RdrName }
1087 : ipvar { L1 (HsIPVar $! unLoc $1) }
1088 | qcname { L1 (HsVar $! unLoc $1) }
1089 | literal { L1 (HsLit $! unLoc $1) }
1090 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1091 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1092 | '(' exp ')' { LL (HsPar $2) }
1093 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1094 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1095 | '[' list ']' { LL (unLoc $2) }
1096 | '[:' parr ':]' { LL (unLoc $2) }
1097 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1098 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1099 | '_' { L1 EWildPat }
1101 -- MetaHaskell Extension
1102 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1103 (L1 $ HsVar (mkUnqual varName
1104 (getTH_ID_SPLICE $1)))) } -- $x
1105 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1107 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1108 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1109 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1110 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1111 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1112 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1113 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1114 return (LL $ HsBracket (PatBr p)) }
1115 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1117 -- arrow notation extension
1118 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1120 cmdargs :: { [LHsCmdTop RdrName] }
1121 : cmdargs acmd { $2 : $1 }
1122 | {- empty -} { [] }
1124 acmd :: { LHsCmdTop RdrName }
1125 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1127 cvtopbody :: { [LHsDecl RdrName] }
1128 : '{' cvtopdecls0 '}' { $2 }
1129 | vocurly cvtopdecls0 close { $2 }
1131 cvtopdecls0 :: { [LHsDecl RdrName] }
1132 : {- empty -} { [] }
1135 texps :: { [LHsExpr RdrName] }
1136 : texps ',' exp { $3 : $1 }
1140 -----------------------------------------------------------------------------
1143 -- The rules below are little bit contorted to keep lexps left-recursive while
1144 -- avoiding another shift/reduce-conflict.
1146 list :: { LHsExpr RdrName }
1147 : exp { L1 $ ExplicitList placeHolderType [$1] }
1148 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1149 | exp '..' { LL $ ArithSeq noPostTcExpr (From $1) }
1150 | exp ',' exp '..' { LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
1151 | exp '..' exp { LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
1152 | exp ',' exp '..' exp { LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1153 | exp pquals { sL (comb2 $1 $>) $ mkHsDo ListComp (reverse (unLoc $2)) $1 }
1155 lexps :: { Located [LHsExpr RdrName] }
1156 : lexps ',' exp { LL ($3 : unLoc $1) }
1157 | exp ',' exp { LL [$3,$1] }
1159 -----------------------------------------------------------------------------
1160 -- List Comprehensions
1162 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1163 -- or a reversed list of Stmts
1164 : pquals1 { case unLoc $1 of
1166 qss -> L1 [L1 (ParStmt stmtss)]
1168 stmtss = [ (reverse qs, undefined)
1172 pquals1 :: { Located [[LStmt RdrName]] }
1173 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1174 | '|' quals { L (getLoc $2) [unLoc $2] }
1176 quals :: { Located [LStmt RdrName] }
1177 : quals ',' qual { LL ($3 : unLoc $1) }
1180 -----------------------------------------------------------------------------
1181 -- Parallel array expressions
1183 -- The rules below are little bit contorted; see the list case for details.
1184 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1185 -- Moreover, we allow explicit arrays with no element (represented by the nil
1186 -- constructor in the list case).
1188 parr :: { LHsExpr RdrName }
1189 : { noLoc (ExplicitPArr placeHolderType []) }
1190 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1191 | lexps { L1 $ ExplicitPArr placeHolderType
1192 (reverse (unLoc $1)) }
1193 | exp '..' exp { LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
1194 | exp ',' exp '..' exp { LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
1195 | exp pquals { sL (comb2 $1 $>) $ mkHsDo PArrComp (reverse (unLoc $2)) $1 }
1197 -- We are reusing `lexps' and `pquals' from the list case.
1199 -----------------------------------------------------------------------------
1200 -- Case alternatives
1202 altslist :: { Located [LMatch RdrName] }
1203 : '{' alts '}' { LL (reverse (unLoc $2)) }
1204 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1206 alts :: { Located [LMatch RdrName] }
1207 : alts1 { L1 (unLoc $1) }
1208 | ';' alts { LL (unLoc $2) }
1210 alts1 :: { Located [LMatch RdrName] }
1211 : alts1 ';' alt { LL ($3 : unLoc $1) }
1212 | alts1 ';' { LL (unLoc $1) }
1215 alt :: { LMatch RdrName }
1216 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1217 return (LL (Match [p] $2 (unLoc $3))) }
1219 alt_rhs :: { Located (GRHSs RdrName) }
1220 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1222 ralt :: { Located [LGRHS RdrName] }
1223 : '->' exp { LL (unguardedRHS $2) }
1224 | gdpats { L1 (reverse (unLoc $1)) }
1226 gdpats :: { Located [LGRHS RdrName] }
1227 : gdpats gdpat { LL ($2 : unLoc $1) }
1230 gdpat :: { LGRHS RdrName }
1231 : '|' quals '->' exp { sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
1233 -----------------------------------------------------------------------------
1234 -- Statement sequences
1236 stmtlist :: { Located [LStmt RdrName] }
1237 : '{' stmts '}' { LL (unLoc $2) }
1238 | vocurly stmts close { $2 }
1240 -- do { ;; s ; s ; ; s ;; }
1241 -- The last Stmt should be an expression, but that's hard to enforce
1242 -- here, because we need too much lookahead if we see do { e ; }
1243 -- So we use ExprStmts throughout, and switch the last one over
1244 -- in ParseUtils.checkDo instead
1245 stmts :: { Located [LStmt RdrName] }
1246 : stmt stmts_help { LL ($1 : unLoc $2) }
1247 | ';' stmts { LL (unLoc $2) }
1248 | {- empty -} { noLoc [] }
1250 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1251 : ';' stmts { LL (unLoc $2) }
1252 | {- empty -} { noLoc [] }
1254 -- For typing stmts at the GHCi prompt, where
1255 -- the input may consist of just comments.
1256 maybe_stmt :: { Maybe (LStmt RdrName) }
1258 | {- nothing -} { Nothing }
1260 stmt :: { LStmt RdrName }
1262 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1263 return (LL $ mkBindStmt p $1) }
1264 | 'rec' stmtlist { LL $ mkRecStmt (unLoc $2) }
1266 qual :: { LStmt RdrName }
1267 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1268 return (LL $ mkBindStmt p $3) }
1269 | exp { L1 $ mkExprStmt $1 }
1270 | 'let' binds { LL $ LetStmt (unLoc $2) }
1272 -----------------------------------------------------------------------------
1273 -- Record Field Update/Construction
1275 fbinds :: { HsRecordBinds RdrName }
1277 | {- empty -} { [] }
1279 fbinds1 :: { HsRecordBinds RdrName }
1280 : fbinds1 ',' fbind { $3 : $1 }
1283 fbind :: { (Located RdrName, LHsExpr RdrName) }
1284 : qvar '=' exp { ($1,$3) }
1286 -----------------------------------------------------------------------------
1287 -- Implicit Parameter Bindings
1289 dbinds :: { Located [LIPBind RdrName] }
1290 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1291 | dbinds ';' { LL (unLoc $1) }
1293 -- | {- empty -} { [] }
1295 dbind :: { LIPBind RdrName }
1296 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1298 ipvar :: { Located (IPName RdrName) }
1299 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1300 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1302 -----------------------------------------------------------------------------
1305 depreclist :: { Located [RdrName] }
1306 depreclist : deprec_var { L1 [unLoc $1] }
1307 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1309 deprec_var :: { Located RdrName }
1310 deprec_var : var { $1 }
1313 -----------------------------------------
1314 -- Data constructors
1315 qcon :: { Located RdrName }
1317 | '(' qconsym ')' { LL (unLoc $2) }
1318 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1319 -- The case of '[:' ':]' is part of the production `parr'
1321 con :: { Located RdrName }
1323 | '(' consym ')' { LL (unLoc $2) }
1324 | sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1326 sysdcon :: { Located DataCon } -- Wired in data constructors
1327 : '(' ')' { LL unitDataCon }
1328 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1329 | '[' ']' { LL nilDataCon }
1331 conop :: { Located RdrName }
1333 | '`' conid '`' { LL (unLoc $2) }
1335 qconop :: { Located RdrName }
1337 | '`' qconid '`' { LL (unLoc $2) }
1339 -----------------------------------------------------------------------------
1340 -- Type constructors
1342 gtycon :: { Located RdrName } -- A "general" qualified tycon
1344 | '(' ')' { LL $ getRdrName unitTyCon }
1345 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1346 | '(' '->' ')' { LL $ getRdrName funTyCon }
1347 | '[' ']' { LL $ listTyCon_RDR }
1348 | '[:' ':]' { LL $ parrTyCon_RDR }
1350 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1352 | '(' qtyconsym ')' { LL (unLoc $2) }
1354 qtyconop :: { Located RdrName } -- Qualified or unqualified
1356 | '`' qtycon '`' { LL (unLoc $2) }
1358 qtycon :: { Located RdrName } -- Qualified or unqualified
1359 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1362 tycon :: { Located RdrName } -- Unqualified
1363 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1365 qtyconsym :: { Located RdrName }
1366 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1369 tyconsym :: { Located RdrName }
1370 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1372 -----------------------------------------------------------------------------
1375 op :: { Located RdrName } -- used in infix decls
1379 varop :: { Located RdrName }
1381 | '`' varid '`' { LL (unLoc $2) }
1383 qop :: { LHsExpr RdrName } -- used in sections
1384 : qvarop { L1 $ HsVar (unLoc $1) }
1385 | qconop { L1 $ HsVar (unLoc $1) }
1387 qopm :: { LHsExpr RdrName } -- used in sections
1388 : qvaropm { L1 $ HsVar (unLoc $1) }
1389 | qconop { L1 $ HsVar (unLoc $1) }
1391 qvarop :: { Located RdrName }
1393 | '`' qvarid '`' { LL (unLoc $2) }
1395 qvaropm :: { Located RdrName }
1396 : qvarsym_no_minus { $1 }
1397 | '`' qvarid '`' { LL (unLoc $2) }
1399 -----------------------------------------------------------------------------
1402 tyvar :: { Located RdrName }
1403 tyvar : tyvarid { $1 }
1404 | '(' tyvarsym ')' { LL (unLoc $2) }
1406 tyvarop :: { Located RdrName }
1407 tyvarop : '`' tyvarid '`' { LL (unLoc $2) }
1410 tyvarid :: { Located RdrName }
1411 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1412 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1413 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1414 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1415 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1417 tyvarsym :: { Located RdrName }
1418 -- Does not include "!", because that is used for strictness marks
1419 -- or ".", because that separates the quantified type vars from the rest
1420 -- or "*", because that's used for kinds
1421 tyvarsym : VARSYM { L1 $! mkUnqual tvName (getVARSYM $1) }
1423 -----------------------------------------------------------------------------
1426 var :: { Located RdrName }
1428 | '(' varsym ')' { LL (unLoc $2) }
1430 qvar :: { Located RdrName }
1432 | '(' varsym ')' { LL (unLoc $2) }
1433 | '(' qvarsym1 ')' { LL (unLoc $2) }
1434 -- We've inlined qvarsym here so that the decision about
1435 -- whether it's a qvar or a var can be postponed until
1436 -- *after* we see the close paren.
1438 qvarid :: { Located RdrName }
1440 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1442 varid :: { Located RdrName }
1443 : varid_no_unsafe { $1 }
1444 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1445 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1446 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1448 varid_no_unsafe :: { Located RdrName }
1449 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1450 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1451 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1453 qvarsym :: { Located RdrName }
1457 qvarsym_no_minus :: { Located RdrName }
1458 : varsym_no_minus { $1 }
1461 qvarsym1 :: { Located RdrName }
1462 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1464 varsym :: { Located RdrName }
1465 : varsym_no_minus { $1 }
1466 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1468 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1469 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1470 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1473 -- These special_ids are treated as keywords in various places,
1474 -- but as ordinary ids elsewhere. 'special_id' collects all these
1475 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1476 special_id :: { Located UserFS }
1478 : 'as' { L1 FSLIT("as") }
1479 | 'qualified' { L1 FSLIT("qualified") }
1480 | 'hiding' { L1 FSLIT("hiding") }
1481 | 'export' { L1 FSLIT("export") }
1482 | 'label' { L1 FSLIT("label") }
1483 | 'dynamic' { L1 FSLIT("dynamic") }
1484 | 'stdcall' { L1 FSLIT("stdcall") }
1485 | 'ccall' { L1 FSLIT("ccall") }
1487 special_sym :: { Located UserFS }
1488 special_sym : '!' { L1 FSLIT("!") }
1489 | '.' { L1 FSLIT(".") }
1490 | '*' { L1 FSLIT("*") }
1492 -----------------------------------------------------------------------------
1493 -- Data constructors
1495 qconid :: { Located RdrName } -- Qualified or unqualified
1497 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1499 conid :: { Located RdrName }
1500 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1502 qconsym :: { Located RdrName } -- Qualified or unqualified
1504 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1506 consym :: { Located RdrName }
1507 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1509 -- ':' means only list cons
1510 | ':' { L1 $ consDataCon_RDR }
1513 -----------------------------------------------------------------------------
1516 literal :: { Located HsLit }
1517 : CHAR { L1 $ HsChar $ getCHAR $1 }
1518 | STRING { L1 $ HsString $ getSTRING $1 }
1519 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1520 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1521 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1522 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1523 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1525 -----------------------------------------------------------------------------
1529 : vccurly { () } -- context popped in lexer.
1530 | error {% popContext }
1532 -----------------------------------------------------------------------------
1533 -- Miscellaneous (mostly renamings)
1535 modid :: { Located Module }
1536 : CONID { L1 $ mkModuleFS (getCONID $1) }
1537 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1540 (unpackFS mod ++ '.':unpackFS c))
1544 : commas ',' { $1 + 1 }
1547 -----------------------------------------------------------------------------
1551 happyError = srcParseFail
1553 getVARID (L _ (ITvarid x)) = x
1554 getCONID (L _ (ITconid x)) = x
1555 getVARSYM (L _ (ITvarsym x)) = x
1556 getCONSYM (L _ (ITconsym x)) = x
1557 getQVARID (L _ (ITqvarid x)) = x
1558 getQCONID (L _ (ITqconid x)) = x
1559 getQVARSYM (L _ (ITqvarsym x)) = x
1560 getQCONSYM (L _ (ITqconsym x)) = x
1561 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1562 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1563 getCHAR (L _ (ITchar x)) = x
1564 getSTRING (L _ (ITstring x)) = x
1565 getINTEGER (L _ (ITinteger x)) = x
1566 getRATIONAL (L _ (ITrational x)) = x
1567 getPRIMCHAR (L _ (ITprimchar x)) = x
1568 getPRIMSTRING (L _ (ITprimstring x)) = x
1569 getPRIMINTEGER (L _ (ITprimint x)) = x
1570 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1571 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1572 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1573 getINLINE (L _ (ITinline_prag b)) = b
1574 getSPEC_INLINE (L _ (ITspec_inline_prag b)) = b
1576 -- Utilities for combining source spans
1577 comb2 :: Located a -> Located b -> SrcSpan
1580 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1581 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1583 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1584 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1585 combineSrcSpans (getLoc c) (getLoc d)
1587 -- strict constructor version:
1589 sL :: SrcSpan -> a -> Located a
1590 sL span a = span `seq` L span a
1592 -- Make a source location for the file. We're a bit lazy here and just
1593 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1594 -- try to find the span of the whole file (ToDo).
1595 fileSrcSpan :: P SrcSpan
1598 let loc = mkSrcLoc (srcLocFile l) 1 0;
1599 return (mkSrcSpan loc loc)