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, parseIface, parseType ) where
13 #define INCLUDE #include
14 INCLUDE "HsVersions.h"
18 import HscTypes ( ModIface, IsBootInterface, DeprecTxt )
21 import TysWiredIn ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
22 listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
23 import Type ( funTyCon )
24 import ForeignCall ( Safety(..), CExportSpec(..), CLabelString,
25 CCallConv(..), CCallTarget(..), defaultCCallConv
27 import OccName ( UserFS, varName, dataName, tcClsName, tvName )
28 import DataCon ( DataCon, dataConName )
29 import SrcLoc ( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
30 SrcSpan, combineLocs, srcLocFile,
33 import CmdLineOpts ( opt_SccProfilingOn )
34 import Type ( Kind, mkArrowKind, liftedTypeKind )
35 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
38 import Bag ( emptyBag )
42 import Maybes ( orElse )
48 -----------------------------------------------------------------------------
49 Conflicts: 34 shift/reduce (1.15)
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 8 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
74 As well as `b` we can have !, QCONSYM, and CONSYM, hence 3 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 '{-# SPECIALISE' { L _ ITspecialise_prag }
188 '{-# SOURCE' { L _ ITsource_prag }
189 '{-# INLINE' { L _ ITinline_prag }
190 '{-# NOINLINE' { L _ ITnoinline_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 parseIface iface
278 %name parseType ctype
279 %tokentype { Located Token }
282 -----------------------------------------------------------------------------
285 -- The place for module deprecation is really too restrictive, but if it
286 -- was allowed at its natural place just before 'module', we get an ugly
287 -- s/r conflict with the second alternative. Another solution would be the
288 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
289 -- either, and DEPRECATED is only expected to be used by people who really
290 -- know what they are doing. :-)
292 module :: { Located (HsModule RdrName) }
293 : 'module' modid maybemoddeprec maybeexports 'where' body
294 {% fileSrcSpan >>= \ loc ->
295 return (L loc (HsModule (Just $2) $4 (fst $6) (snd $6) $3)) }
296 | missing_module_keyword top close
297 {% fileSrcSpan >>= \ loc ->
298 return (L loc (HsModule Nothing Nothing
299 (fst $2) (snd $2) Nothing)) }
301 missing_module_keyword :: { () }
302 : {- empty -} {% pushCurrentContext }
304 maybemoddeprec :: { Maybe DeprecTxt }
305 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
306 | {- empty -} { Nothing }
308 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
310 | vocurly top close { $2 }
312 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
313 : importdecls { (reverse $1,[]) }
314 | importdecls ';' cvtopdecls { (reverse $1,$3) }
315 | cvtopdecls { ([],$1) }
317 cvtopdecls :: { [LHsDecl RdrName] }
318 : topdecls { cvTopDecls $1 }
320 -----------------------------------------------------------------------------
321 -- Interfaces (.hi-boot files)
323 iface :: { ModIface }
324 : 'module' modid 'where' ifacebody { mkBootIface (unLoc $2) $4 }
326 ifacebody :: { [HsDecl RdrName] }
327 : '{' ifacedecls '}' { $2 }
328 | vocurly ifacedecls close { $2 }
330 ifacedecls :: { [HsDecl RdrName] }
331 : ifacedecl ';' ifacedecls { $1 : $3 }
332 | ';' ifacedecls { $2 }
336 ifacedecl :: { HsDecl RdrName }
339 | 'type' syn_hdr '=' ctype
340 { let (tc,tvs) = $2 in TyClD (TySynonym tc tvs $4) }
341 | 'data' tycl_hdr constrs -- No deriving in hi-boot
342 { TyClD (mkTyData DataType $2 Nothing (reverse (unLoc $3)) Nothing) }
343 | 'data' tycl_hdr 'where' gadt_constrlist
344 { TyClD (mkTyData DataType $2 Nothing (reverse (unLoc $4)) Nothing) }
345 | 'newtype' tycl_hdr -- Constructor is optional
346 { TyClD (mkTyData NewType $2 Nothing [] Nothing) }
347 | 'newtype' tycl_hdr '=' newconstr
348 { TyClD (mkTyData NewType $2 Nothing [$4] Nothing) }
349 | 'class' tycl_hdr fds
350 { TyClD (mkClassDecl (unLoc $2) (unLoc $3) [] emptyBag) }
352 -----------------------------------------------------------------------------
355 maybeexports :: { Maybe [LIE RdrName] }
356 : '(' exportlist ')' { Just $2 }
357 | {- empty -} { Nothing }
359 exportlist :: { [LIE RdrName] }
360 : exportlist ',' export { $3 : $1 }
361 | exportlist ',' { $1 }
365 -- No longer allow things like [] and (,,,) to be exported
366 -- They are built in syntax, always available
367 export :: { LIE RdrName }
368 : qvar { L1 (IEVar (unLoc $1)) }
369 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
370 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
371 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
372 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
373 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
375 qcnames :: { [RdrName] }
376 : qcnames ',' qcname { unLoc $3 : $1 }
377 | qcname { [unLoc $1] }
379 qcname :: { Located RdrName } -- Variable or data constructor
383 -----------------------------------------------------------------------------
384 -- Import Declarations
386 -- import decls can be *empty*, or even just a string of semicolons
387 -- whereas topdecls must contain at least one topdecl.
389 importdecls :: { [LImportDecl RdrName] }
390 : importdecls ';' importdecl { $3 : $1 }
391 | importdecls ';' { $1 }
392 | importdecl { [ $1 ] }
395 importdecl :: { LImportDecl RdrName }
396 : 'import' maybe_src optqualified modid maybeas maybeimpspec
397 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
399 maybe_src :: { IsBootInterface }
400 : '{-# SOURCE' '#-}' { True }
401 | {- empty -} { False }
403 optqualified :: { Bool }
404 : 'qualified' { True }
405 | {- empty -} { False }
407 maybeas :: { Located (Maybe Module) }
408 : 'as' modid { LL (Just (unLoc $2)) }
409 | {- empty -} { noLoc Nothing }
411 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
412 : impspec { L1 (Just (unLoc $1)) }
413 | {- empty -} { noLoc Nothing }
415 impspec :: { Located (Bool, [LIE RdrName]) }
416 : '(' exportlist ')' { LL (False, reverse $2) }
417 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
419 -----------------------------------------------------------------------------
420 -- Fixity Declarations
424 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
426 infix :: { Located FixityDirection }
427 : 'infix' { L1 InfixN }
428 | 'infixl' { L1 InfixL }
429 | 'infixr' { L1 InfixR }
431 ops :: { Located [Located RdrName] }
432 : ops ',' op { LL ($3 : unLoc $1) }
435 -----------------------------------------------------------------------------
436 -- Top-Level Declarations
438 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
439 : topdecls ';' topdecl { $1 `appOL` $3 }
440 | topdecls ';' { $1 }
443 topdecl :: { OrdList (LHsDecl RdrName) }
444 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
445 | 'instance' inst_type where
446 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
447 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
448 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
449 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
450 | '{-# DEPRECATED' deprecations '#-}' { $2 }
451 | '{-# RULES' rules '#-}' { $2 }
452 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
455 tycl_decl :: { LTyClDecl RdrName }
456 : 'type' syn_hdr '=' ctype
457 -- Note ctype, not sigtype.
458 -- We allow an explicit for-all but we don't insert one
459 -- in type Foo a = (b,b)
460 -- Instead we just say b is out of scope
461 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
463 | 'data' tycl_hdr constrs deriving
464 { L (comb4 $1 $2 $3 $4)
465 (mkTyData DataType $2 Nothing (reverse (unLoc $3)) (unLoc $4)) }
467 | 'data' tycl_hdr opt_kind_sig 'where' gadt_constrlist -- No deriving for GADTs
468 { L (comb4 $1 $2 $4 $5)
469 (mkTyData DataType $2 $3 (reverse (unLoc $5)) Nothing) }
471 | 'newtype' tycl_hdr '=' newconstr deriving
473 (mkTyData NewType $2 Nothing [$4] (unLoc $5)) }
475 | 'class' tycl_hdr fds where
477 (binds,sigs) = cvBindsAndSigs (unLoc $4)
479 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
482 opt_kind_sig :: { Maybe Kind }
484 | '::' kind { Just $2 }
486 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
487 -- We don't retain the syntax of an infix
488 -- type synonym declaration. Oh well.
489 : tycon tv_bndrs { ($1, $2) }
490 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
492 -- tycl_hdr parses the header of a type or class decl,
493 -- which takes the form
496 -- (Eq a, Ord b) => T a b
497 -- Rather a lot of inlining here, else we get reduce/reduce errors
498 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
499 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
500 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
502 -----------------------------------------------------------------------------
503 -- Nested declarations
505 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
506 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
507 | decls ';' { LL (unLoc $1) }
509 | {- empty -} { noLoc nilOL }
512 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
513 : '{' decls '}' { LL (unLoc $2) }
514 | vocurly decls close { $2 }
516 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
517 -- No implicit parameters
518 : 'where' decllist { LL (unLoc $2) }
519 | {- empty -} { noLoc nilOL }
521 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
522 : decllist { L1 [cvBindGroup (unLoc $1)] }
523 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
524 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
526 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
527 : 'where' binds { LL (unLoc $2) }
528 | {- empty -} { noLoc [] }
531 -----------------------------------------------------------------------------
532 -- Transformation Rules
534 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
535 : rules ';' rule { $1 `snocOL` $3 }
538 | {- empty -} { nilOL }
540 rule :: { LHsDecl RdrName }
541 : STRING activation rule_forall infixexp '=' exp
542 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
544 activation :: { Activation } -- Omitted means AlwaysActive
545 : {- empty -} { AlwaysActive }
546 | explicit_activation { $1 }
548 inverse_activation :: { Activation } -- Omitted means NeverActive
549 : {- empty -} { NeverActive }
550 | explicit_activation { $1 }
552 explicit_activation :: { Activation } -- In brackets
553 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
554 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
556 rule_forall :: { [RuleBndr RdrName] }
557 : 'forall' rule_var_list '.' { $2 }
560 rule_var_list :: { [RuleBndr RdrName] }
562 | rule_var rule_var_list { $1 : $2 }
564 rule_var :: { RuleBndr RdrName }
565 : varid { RuleBndr $1 }
566 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
568 -----------------------------------------------------------------------------
569 -- Deprecations (c.f. rules)
571 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
572 : deprecations ';' deprecation { $1 `appOL` $3 }
573 | deprecations ';' { $1 }
575 | {- empty -} { nilOL }
577 -- SUP: TEMPORARY HACK, not checking for `module Foo'
578 deprecation :: { OrdList (LHsDecl RdrName) }
580 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
584 -----------------------------------------------------------------------------
585 -- Foreign import and export declarations
587 -- for the time being, the following accepts foreign declarations conforming
588 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
590 -- * a flag indicates whether pre-standard declarations have been used and
591 -- triggers a deprecation warning further down the road
593 -- NB: The first two rules could be combined into one by replacing `safety1'
594 -- with `safety'. However, the combined rule conflicts with the
597 fdecl :: { LHsDecl RdrName }
598 fdecl : 'import' callconv safety1 fspec
599 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
600 | 'import' callconv fspec
601 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
603 | 'export' callconv fspec
604 {% mkExport $2 (unLoc $3) >>= return.LL }
605 -- the following syntax is DEPRECATED
606 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
607 | fdecl2DEPRECATED { L1 (unLoc $1) }
609 fdecl1DEPRECATED :: { LForeignDecl RdrName }
611 ----------- DEPRECATED label decls ------------
612 : 'label' ext_name varid '::' sigtype
613 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
614 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
616 ----------- DEPRECATED ccall/stdcall decls ------------
618 -- NB: This business with the case expression below may seem overly
619 -- complicated, but it is necessary to avoid some conflicts.
621 -- DEPRECATED variant #1: lack of a calling convention specification
623 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
625 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
627 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
628 (CFunction target)) True }
630 -- DEPRECATED variant #2: external name consists of two separate strings
631 -- (module name and function name) (import)
632 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
634 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
635 CCall cconv -> return $
637 imp = CFunction (StaticTarget (getSTRING $4))
639 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
641 -- DEPRECATED variant #3: `unsafe' after entity
642 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
644 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
645 CCall cconv -> return $
647 imp = CFunction (StaticTarget (getSTRING $3))
649 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
651 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
652 -- an explicit calling convention (import)
653 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
654 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
655 (CFunction DynamicTarget)) True }
657 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
658 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
660 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
661 CCall cconv -> return $
662 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
663 (CFunction DynamicTarget)) True }
665 -- DEPRECATED variant #6: lack of a calling convention specification
667 | 'export' {-no callconv-} ext_name varid '::' sigtype
668 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
669 defaultCCallConv)) True }
671 -- DEPRECATED variant #7: external name consists of two separate strings
672 -- (module name and function name) (export)
673 | 'export' callconv STRING STRING varid '::' sigtype
675 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
676 CCall cconv -> return $
677 LL $ ForeignExport $5 $7
678 (CExport (CExportStatic (getSTRING $4) cconv)) True }
680 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
681 -- an explicit calling convention (export)
682 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
683 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
686 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
687 | 'export' callconv 'dynamic' varid '::' sigtype
689 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
690 CCall cconv -> return $
691 LL $ ForeignImport $4 $6
692 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
694 ----------- DEPRECATED .NET decls ------------
695 -- NB: removed the .NET call declaration, as it is entirely subsumed
696 -- by the new standard FFI declarations
698 fdecl2DEPRECATED :: { LHsDecl RdrName }
700 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
701 -- left this one unchanged for the moment as type imports are not
702 -- covered currently by the FFI standard -=chak
705 callconv :: { CallConv }
706 : 'stdcall' { CCall StdCallConv }
707 | 'ccall' { CCall CCallConv }
708 | 'dotnet' { DNCall }
711 : 'unsafe' { PlayRisky }
712 | 'safe' { PlaySafe False }
713 | 'threadsafe' { PlaySafe True }
714 | {- empty -} { PlaySafe False }
716 safety1 :: { Safety }
717 : 'unsafe' { PlayRisky }
718 | 'safe' { PlaySafe False }
719 | 'threadsafe' { PlaySafe True }
720 -- only needed to avoid conflicts with the DEPRECATED rules
722 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
723 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
724 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
725 -- if the entity string is missing, it defaults to the empty string;
726 -- the meaning of an empty entity string depends on the calling
730 ext_name :: { Maybe CLabelString }
731 : STRING { Just (getSTRING $1) }
732 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
733 | {- empty -} { Nothing }
736 -----------------------------------------------------------------------------
739 opt_sig :: { Maybe (LHsType RdrName) }
740 : {- empty -} { Nothing }
741 | '::' sigtype { Just $2 }
743 opt_asig :: { Maybe (LHsType RdrName) }
744 : {- empty -} { Nothing }
745 | '::' atype { Just $2 }
747 sigtypes1 :: { [LHsType RdrName] }
749 | sigtype ',' sigtypes1 { $1 : $3 }
751 sigtype :: { LHsType RdrName }
752 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
753 -- Wrap an Implicit forall if there isn't one there already
755 sig_vars :: { Located [Located RdrName] }
756 : sig_vars ',' var { LL ($3 : unLoc $1) }
759 -----------------------------------------------------------------------------
762 strict_mark :: { Located HsBang }
763 : '!' { L1 HsStrict }
764 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
766 -- A ctype is a for-all type
767 ctype :: { LHsType RdrName }
768 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
769 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
770 -- A type of form (context => type) is an *implicit* HsForAllTy
773 -- We parse a context as a btype so that we don't get reduce/reduce
774 -- errors in ctype. The basic problem is that
776 -- looks so much like a tuple type. We can't tell until we find the =>
777 context :: { LHsContext RdrName }
778 : btype {% checkContext $1 }
780 type :: { LHsType RdrName }
781 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
784 gentype :: { LHsType RdrName }
786 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
787 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
788 | btype '->' gentype { LL $ HsFunTy $1 $3 }
790 btype :: { LHsType RdrName }
791 : btype atype { LL $ HsAppTy $1 $2 }
794 atype :: { LHsType RdrName }
795 : gtycon { L1 (HsTyVar (unLoc $1)) }
796 | tyvar { L1 (HsTyVar (unLoc $1)) }
797 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
798 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
799 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
800 | '[' type ']' { LL $ HsListTy $2 }
801 | '[:' type ':]' { LL $ HsPArrTy $2 }
802 | '(' ctype ')' { LL $ HsParTy $2 }
803 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
805 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
807 -- An inst_type is what occurs in the head of an instance decl
808 -- e.g. (Foo a, Gaz b) => Wibble a b
809 -- It's kept as a single type, with a MonoDictTy at the right
810 -- hand corner, for convenience.
811 inst_type :: { LHsType RdrName }
812 : sigtype {% checkInstType $1 }
814 inst_types1 :: { [LHsType RdrName] }
816 | inst_type ',' inst_types1 { $1 : $3 }
818 comma_types0 :: { [LHsType RdrName] }
819 : comma_types1 { $1 }
822 comma_types1 :: { [LHsType RdrName] }
824 | type ',' comma_types1 { $1 : $3 }
826 tv_bndrs :: { [LHsTyVarBndr RdrName] }
827 : tv_bndr tv_bndrs { $1 : $2 }
830 tv_bndr :: { LHsTyVarBndr RdrName }
831 : tyvar { L1 (UserTyVar (unLoc $1)) }
832 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
834 fds :: { Located [Located ([RdrName], [RdrName])] }
835 : {- empty -} { noLoc [] }
836 | '|' fds1 { LL (reverse (unLoc $2)) }
838 fds1 :: { Located [Located ([RdrName], [RdrName])] }
839 : fds1 ',' fd { LL ($3 : unLoc $1) }
842 fd :: { Located ([RdrName], [RdrName]) }
843 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
844 (reverse (unLoc $1), reverse (unLoc $3)) }
846 varids0 :: { Located [RdrName] }
847 : {- empty -} { noLoc [] }
848 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
850 -----------------------------------------------------------------------------
855 | akind '->' kind { mkArrowKind $1 $3 }
858 : '*' { liftedTypeKind }
859 | '(' kind ')' { $2 }
862 -----------------------------------------------------------------------------
863 -- Datatype declarations
865 newconstr :: { LConDecl RdrName }
866 : conid atype { LL $ ConDecl $1 [] (noLoc []) (PrefixCon [$2]) }
867 | conid '{' var '::' ctype '}'
868 { LL $ ConDecl $1 [] (noLoc []) (RecCon [($3, $5)]) }
870 gadt_constrlist :: { Located [LConDecl RdrName] }
871 : '{' gadt_constrs '}' { LL (unLoc $2) }
872 | vocurly gadt_constrs close { $2 }
874 gadt_constrs :: { Located [LConDecl RdrName] }
875 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
876 | gadt_constrs ';' { $1 }
877 | gadt_constr { L1 [$1] }
879 gadt_constr :: { LConDecl RdrName }
881 { LL (GadtDecl $1 $3) }
883 constrs :: { Located [LConDecl RdrName] }
884 : {- empty; a GHC extension -} { noLoc [] }
885 | '=' constrs1 { LL (unLoc $2) }
887 constrs1 :: { Located [LConDecl RdrName] }
888 : constrs1 '|' constr { LL ($3 : unLoc $1) }
891 constr :: { LConDecl RdrName }
892 : forall context '=>' constr_stuff
893 { let (con,details) = unLoc $4 in
894 LL (ConDecl con (unLoc $1) $2 details) }
895 | forall constr_stuff
896 { let (con,details) = unLoc $2 in
897 LL (ConDecl con (unLoc $1) (noLoc []) details) }
899 forall :: { Located [LHsTyVarBndr RdrName] }
900 : 'forall' tv_bndrs '.' { LL $2 }
901 | {- empty -} { noLoc [] }
903 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
904 -- We parse the constructor declaration
906 -- as a btype (treating C as a type constructor) and then convert C to be
907 -- a data constructor. Reason: it might continue like this:
909 -- in which case C really would be a type constructor. We can't resolve this
910 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
911 : btype {% mkPrefixCon $1 [] >>= return.LL }
912 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
913 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
914 | btype conop btype { LL ($2, InfixCon $1 $3) }
916 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
917 : fielddecl ',' fielddecls { unLoc $1 : $3 }
918 | fielddecl { [unLoc $1] }
920 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
921 : sig_vars '::' ctype { LL (reverse (unLoc $1), $3) }
923 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
924 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
925 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
926 -- We don't allow a context, but that's sorted out by the type checker.
927 deriving :: { Located (Maybe [LHsType RdrName]) }
928 : {- empty -} { noLoc Nothing }
929 | 'deriving' qtycon {% do { let { L loc tv = $2 }
930 ; p <- checkInstType (L loc (HsTyVar tv))
931 ; return (LL (Just [p])) } }
932 | 'deriving' '(' ')' { LL (Just []) }
933 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
934 -- Glasgow extension: allow partial
935 -- applications in derivings
937 -----------------------------------------------------------------------------
940 {- There's an awkward overlap with a type signature. Consider
941 f :: Int -> Int = ...rhs...
942 Then we can't tell whether it's a type signature or a value
943 definition with a result signature until we see the '='.
944 So we have to inline enough to postpone reductions until we know.
948 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
949 instead of qvar, we get another shift/reduce-conflict. Consider the
952 { (^^) :: Int->Int ; } Type signature; only var allowed
954 { (^^) :: Int->Int = ... ; } Value defn with result signature;
955 qvar allowed (because of instance decls)
957 We can't tell whether to reduce var to qvar until after we've read the signatures.
960 decl :: { Located (OrdList (LHsDecl RdrName)) }
962 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
963 return (LL $ unitOL (LL $ ValD r)) } }
965 rhs :: { Located (GRHSs RdrName) }
966 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
967 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
969 gdrhs :: { Located [LGRHS RdrName] }
970 : gdrhs gdrh { LL ($2 : unLoc $1) }
973 gdrh :: { LGRHS RdrName }
974 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
977 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
978 : infixexp '::' sigtype
979 {% do s <- checkValSig $1 $3;
980 return (LL $ unitOL (LL $ SigD s)) }
981 -- See the above notes for why we need infixexp here
982 | var ',' sig_vars '::' sigtype
983 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
984 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
986 | '{-# INLINE' activation qvar '#-}'
987 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
988 | '{-# NOINLINE' inverse_activation qvar '#-}'
989 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
990 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
991 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
993 | '{-# SPECIALISE' 'instance' inst_type '#-}'
994 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
996 -----------------------------------------------------------------------------
999 exp :: { LHsExpr RdrName }
1000 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
1001 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
1002 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
1003 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
1004 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1007 infixexp :: { LHsExpr RdrName }
1009 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1011 exp10 :: { LHsExpr RdrName }
1012 : '\\' aexp aexps opt_asig '->' exp
1013 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
1014 return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
1015 (GRHSs (unguardedRHS $6) []
1017 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1018 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1019 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1020 | '-' fexp { LL $ mkHsNegApp $2 }
1022 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1023 checkDo loc (unLoc $2) >>= \ stmts ->
1024 return (L loc (mkHsDo DoExpr stmts)) }
1025 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1026 checkMDo loc (unLoc $2) >>= \ stmts ->
1027 return (L loc (mkHsDo MDoExpr stmts)) }
1029 | scc_annot exp { LL $ if opt_SccProfilingOn
1030 then HsSCC (unLoc $1) $2
1033 | 'proc' aexp '->' exp
1034 {% checkPattern $2 >>= \ p ->
1035 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1036 placeHolderType undefined)) }
1037 -- TODO: is LL right here?
1039 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1040 -- hdaume: core annotation
1043 scc_annot :: { Located FastString }
1044 : '_scc_' STRING { LL $ getSTRING $2 }
1045 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1047 fexp :: { LHsExpr RdrName }
1048 : fexp aexp { LL $ HsApp $1 $2 }
1051 aexps :: { [LHsExpr RdrName] }
1052 : aexps aexp { $2 : $1 }
1053 | {- empty -} { [] }
1055 aexp :: { LHsExpr RdrName }
1056 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1057 | '~' aexp { LL $ ELazyPat $2 }
1060 aexp1 :: { LHsExpr RdrName }
1061 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1066 -- Here was the syntax for type applications that I was planning
1067 -- but there are difficulties (e.g. what order for type args)
1068 -- so it's not enabled yet.
1069 -- But this case *is* used for the left hand side of a generic definition,
1070 -- which is parsed as an expression before being munged into a pattern
1071 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1072 (sL (getLoc $3) (HsType $3)) }
1074 aexp2 :: { LHsExpr RdrName }
1075 : ipvar { L1 (HsIPVar $! unLoc $1) }
1076 | qcname { L1 (HsVar $! unLoc $1) }
1077 | literal { L1 (HsLit $! unLoc $1) }
1078 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1079 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1080 | '(' exp ')' { LL (HsPar $2) }
1081 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1082 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1083 | '[' list ']' { LL (unLoc $2) }
1084 | '[:' parr ':]' { LL (unLoc $2) }
1085 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1086 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1087 | '_' { L1 EWildPat }
1089 -- MetaHaskell Extension
1090 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1091 (L1 $ HsVar (mkUnqual varName
1092 (getTH_ID_SPLICE $1)))) } -- $x
1093 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1095 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1096 | TH_VAR_QUOTE gcon { LL $ HsBracket (VarBr (unLoc $2)) }
1097 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1098 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1099 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1100 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1101 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1102 return (LL $ HsBracket (PatBr p)) }
1103 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1105 -- arrow notation extension
1106 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1108 cmdargs :: { [LHsCmdTop RdrName] }
1109 : cmdargs acmd { $2 : $1 }
1110 | {- empty -} { [] }
1112 acmd :: { LHsCmdTop RdrName }
1113 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1115 cvtopbody :: { [LHsDecl RdrName] }
1116 : '{' cvtopdecls0 '}' { $2 }
1117 | vocurly cvtopdecls0 close { $2 }
1119 cvtopdecls0 :: { [LHsDecl RdrName] }
1120 : {- empty -} { [] }
1123 texps :: { [LHsExpr RdrName] }
1124 : texps ',' exp { $3 : $1 }
1128 -----------------------------------------------------------------------------
1131 -- The rules below are little bit contorted to keep lexps left-recursive while
1132 -- avoiding another shift/reduce-conflict.
1134 list :: { LHsExpr RdrName }
1135 : exp { L1 $ ExplicitList placeHolderType [$1] }
1136 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1137 | exp '..' { LL $ ArithSeqIn (From $1) }
1138 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1139 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1140 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1141 | exp pquals { LL $ mkHsDo ListComp
1142 (reverse (L (getLoc $1) (ResultStmt $1) :
1145 lexps :: { Located [LHsExpr RdrName] }
1146 : lexps ',' exp { LL ($3 : unLoc $1) }
1147 | exp ',' exp { LL [$3,$1] }
1149 -----------------------------------------------------------------------------
1150 -- List Comprehensions
1152 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1153 -- or a reversed list of Stmts
1154 : pquals1 { case unLoc $1 of
1156 qss -> L1 [L1 (ParStmt stmtss)]
1158 stmtss = [ (reverse qs, undefined)
1162 pquals1 :: { Located [[LStmt RdrName]] }
1163 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1164 | '|' quals { L (getLoc $2) [unLoc $2] }
1166 quals :: { Located [LStmt RdrName] }
1167 : quals ',' qual { LL ($3 : unLoc $1) }
1170 -----------------------------------------------------------------------------
1171 -- Parallel array expressions
1173 -- The rules below are little bit contorted; see the list case for details.
1174 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1175 -- Moreover, we allow explicit arrays with no element (represented by the nil
1176 -- constructor in the list case).
1178 parr :: { LHsExpr RdrName }
1179 : { noLoc (ExplicitPArr placeHolderType []) }
1180 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1181 | lexps { L1 $ ExplicitPArr placeHolderType
1182 (reverse (unLoc $1)) }
1183 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1184 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1185 | exp pquals { LL $ mkHsDo PArrComp
1186 (reverse (L (getLoc $1) (ResultStmt $1) :
1190 -- We are reusing `lexps' and `pquals' from the list case.
1192 -----------------------------------------------------------------------------
1193 -- Case alternatives
1195 altslist :: { Located [LMatch RdrName] }
1196 : '{' alts '}' { LL (reverse (unLoc $2)) }
1197 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1199 alts :: { Located [LMatch RdrName] }
1200 : alts1 { L1 (unLoc $1) }
1201 | ';' alts { LL (unLoc $2) }
1203 alts1 :: { Located [LMatch RdrName] }
1204 : alts1 ';' alt { LL ($3 : unLoc $1) }
1205 | alts1 ';' { LL (unLoc $1) }
1208 alt :: { LMatch RdrName }
1209 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1210 return (LL (Match [p] $2 (unLoc $3))) }
1212 alt_rhs :: { Located (GRHSs RdrName) }
1213 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1215 ralt :: { Located [LGRHS RdrName] }
1216 : '->' exp { LL (unguardedRHS $2) }
1217 | gdpats { L1 (reverse (unLoc $1)) }
1219 gdpats :: { Located [LGRHS RdrName] }
1220 : gdpats gdpat { LL ($2 : unLoc $1) }
1223 gdpat :: { LGRHS RdrName }
1224 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1225 in LL $ GRHS (reverse (r : unLoc $2)) }
1227 -----------------------------------------------------------------------------
1228 -- Statement sequences
1230 stmtlist :: { Located [LStmt RdrName] }
1231 : '{' stmts '}' { LL (unLoc $2) }
1232 | vocurly stmts close { $2 }
1234 -- do { ;; s ; s ; ; s ;; }
1235 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1236 -- here, because we need too much lookahead if we see do { e ; }
1237 -- So we use ExprStmts throughout, and switch the last one over
1238 -- in ParseUtils.checkDo instead
1239 stmts :: { Located [LStmt RdrName] }
1240 : stmt stmts_help { LL ($1 : unLoc $2) }
1241 | ';' stmts { LL (unLoc $2) }
1242 | {- empty -} { noLoc [] }
1244 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1245 : ';' stmts { LL (unLoc $2) }
1246 | {- empty -} { noLoc [] }
1248 -- For typing stmts at the GHCi prompt, where
1249 -- the input may consist of just comments.
1250 maybe_stmt :: { Maybe (LStmt RdrName) }
1252 | {- nothing -} { Nothing }
1254 stmt :: { LStmt RdrName }
1256 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1257 return (LL $ BindStmt p $1) }
1258 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1260 qual :: { LStmt RdrName }
1261 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1262 return (LL $ BindStmt p $3) }
1263 | exp { L1 $ ExprStmt $1 placeHolderType }
1264 | 'let' binds { LL $ LetStmt (unLoc $2) }
1266 -----------------------------------------------------------------------------
1267 -- Record Field Update/Construction
1269 fbinds :: { HsRecordBinds RdrName }
1271 | {- empty -} { [] }
1273 fbinds1 :: { HsRecordBinds RdrName }
1274 : fbinds1 ',' fbind { $3 : $1 }
1277 fbind :: { (Located RdrName, LHsExpr RdrName) }
1278 : qvar '=' exp { ($1,$3) }
1280 -----------------------------------------------------------------------------
1281 -- Implicit Parameter Bindings
1283 dbinds :: { Located [LIPBind RdrName] }
1284 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1285 | dbinds ';' { LL (unLoc $1) }
1287 -- | {- empty -} { [] }
1289 dbind :: { LIPBind RdrName }
1290 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1292 -----------------------------------------------------------------------------
1293 -- Variables, Constructors and Operators.
1295 identifier :: { Located RdrName }
1301 depreclist :: { Located [RdrName] }
1302 depreclist : deprec_var { L1 [unLoc $1] }
1303 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1305 deprec_var :: { Located RdrName }
1306 deprec_var : var { $1 }
1309 gcon :: { Located RdrName } -- Data constructor namespace
1310 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1312 -- the case of '[:' ':]' is part of the production `parr'
1314 sysdcon :: { Located DataCon } -- Wired in data constructors
1315 : '(' ')' { LL unitDataCon }
1316 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1317 | '[' ']' { LL nilDataCon }
1319 var :: { Located RdrName }
1321 | '(' varsym ')' { LL (unLoc $2) }
1323 qvar :: { Located RdrName }
1325 | '(' varsym ')' { LL (unLoc $2) }
1326 | '(' qvarsym1 ')' { LL (unLoc $2) }
1327 -- We've inlined qvarsym here so that the decision about
1328 -- whether it's a qvar or a var can be postponed until
1329 -- *after* we see the close paren.
1331 ipvar :: { Located (IPName RdrName) }
1332 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1333 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1335 qcon :: { Located RdrName }
1337 | '(' qconsym ')' { LL (unLoc $2) }
1339 varop :: { Located RdrName }
1341 | '`' varid '`' { LL (unLoc $2) }
1343 qvarop :: { Located RdrName }
1345 | '`' qvarid '`' { LL (unLoc $2) }
1347 qvaropm :: { Located RdrName }
1348 : qvarsym_no_minus { $1 }
1349 | '`' qvarid '`' { LL (unLoc $2) }
1351 conop :: { Located RdrName }
1353 | '`' conid '`' { LL (unLoc $2) }
1355 qconop :: { Located RdrName }
1357 | '`' qconid '`' { LL (unLoc $2) }
1359 -----------------------------------------------------------------------------
1360 -- Type constructors
1362 gtycon :: { Located RdrName } -- A "general" qualified tycon
1364 | '(' ')' { LL $ getRdrName unitTyCon }
1365 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1366 | '(' '->' ')' { LL $ getRdrName funTyCon }
1367 | '[' ']' { LL $ listTyCon_RDR }
1368 | '[:' ':]' { LL $ parrTyCon_RDR }
1370 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1372 | '(' qtyconsym ')' { LL (unLoc $2) }
1374 qtyconop :: { Located RdrName } -- Qualified or unqualified
1376 | '`' qtycon '`' { LL (unLoc $2) }
1378 tyconop :: { Located RdrName } -- Unqualified
1380 | '`' tycon '`' { LL (unLoc $2) }
1382 qtycon :: { Located RdrName } -- Qualified or unqualified
1383 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1386 tycon :: { Located RdrName } -- Unqualified
1387 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1389 qtyconsym :: { Located RdrName }
1390 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1393 tyconsym :: { Located RdrName }
1394 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1396 -----------------------------------------------------------------------------
1399 op :: { Located RdrName } -- used in infix decls
1403 qop :: { LHsExpr RdrName } -- used in sections
1404 : qvarop { L1 $ HsVar (unLoc $1) }
1405 | qconop { L1 $ HsVar (unLoc $1) }
1407 qopm :: { LHsExpr RdrName } -- used in sections
1408 : qvaropm { L1 $ HsVar (unLoc $1) }
1409 | qconop { L1 $ HsVar (unLoc $1) }
1411 -----------------------------------------------------------------------------
1414 qvarid :: { Located RdrName }
1416 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1418 varid :: { Located RdrName }
1419 : varid_no_unsafe { $1 }
1420 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1421 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1422 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1424 varid_no_unsafe :: { Located RdrName }
1425 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1426 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1427 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1429 tyvar :: { Located RdrName }
1430 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1431 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1432 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1433 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1434 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1436 -- These special_ids are treated as keywords in various places,
1437 -- but as ordinary ids elsewhere. 'special_id' collects all these
1438 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1439 special_id :: { Located UserFS }
1441 : 'as' { L1 FSLIT("as") }
1442 | 'qualified' { L1 FSLIT("qualified") }
1443 | 'hiding' { L1 FSLIT("hiding") }
1444 | 'export' { L1 FSLIT("export") }
1445 | 'label' { L1 FSLIT("label") }
1446 | 'dynamic' { L1 FSLIT("dynamic") }
1447 | 'stdcall' { L1 FSLIT("stdcall") }
1448 | 'ccall' { L1 FSLIT("ccall") }
1450 -----------------------------------------------------------------------------
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 -- See comments with special_id
1474 special_sym :: { Located UserFS }
1475 special_sym : '!' { L1 FSLIT("!") }
1476 | '.' { L1 FSLIT(".") }
1477 | '*' { L1 FSLIT("*") }
1479 -----------------------------------------------------------------------------
1480 -- Data constructors
1482 qconid :: { Located RdrName } -- Qualified or unqualified
1484 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1486 conid :: { Located RdrName }
1487 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1489 qconsym :: { Located RdrName } -- Qualified or unqualified
1491 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1493 consym :: { Located RdrName }
1494 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1496 -- ':' means only list cons
1497 | ':' { L1 $ consDataCon_RDR }
1500 -----------------------------------------------------------------------------
1503 literal :: { Located HsLit }
1504 : CHAR { L1 $ HsChar $ getCHAR $1 }
1505 | STRING { L1 $ HsString $ getSTRING $1 }
1506 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1507 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1508 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1509 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1510 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1512 -----------------------------------------------------------------------------
1516 : vccurly { () } -- context popped in lexer.
1517 | error {% popContext }
1519 -----------------------------------------------------------------------------
1520 -- Miscellaneous (mostly renamings)
1522 modid :: { Located Module }
1523 : CONID { L1 $ mkModuleFS (getCONID $1) }
1524 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1527 (unpackFS mod ++ '.':unpackFS c))
1531 : commas ',' { $1 + 1 }
1534 -----------------------------------------------------------------------------
1538 happyError = srcParseFail
1540 getVARID (L _ (ITvarid x)) = x
1541 getCONID (L _ (ITconid x)) = x
1542 getVARSYM (L _ (ITvarsym x)) = x
1543 getCONSYM (L _ (ITconsym x)) = x
1544 getQVARID (L _ (ITqvarid x)) = x
1545 getQCONID (L _ (ITqconid x)) = x
1546 getQVARSYM (L _ (ITqvarsym x)) = x
1547 getQCONSYM (L _ (ITqconsym x)) = x
1548 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1549 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1550 getCHAR (L _ (ITchar x)) = x
1551 getSTRING (L _ (ITstring x)) = x
1552 getINTEGER (L _ (ITinteger x)) = x
1553 getRATIONAL (L _ (ITrational x)) = x
1554 getPRIMCHAR (L _ (ITprimchar x)) = x
1555 getPRIMSTRING (L _ (ITprimstring x)) = x
1556 getPRIMINTEGER (L _ (ITprimint x)) = x
1557 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1558 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1559 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1561 -- Utilities for combining source spans
1562 comb2 :: Located a -> Located b -> SrcSpan
1565 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1566 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1568 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1569 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1570 combineSrcSpans (getLoc c) (getLoc d)
1572 -- strict constructor version:
1574 sL :: SrcSpan -> a -> Located a
1575 sL span a = span `seq` L span a
1577 -- Make a source location for the file. We're a bit lazy here and just
1578 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1579 -- try to find the span of the whole file (ToDo).
1580 fileSrcSpan :: P SrcSpan
1583 let loc = mkSrcLoc (srcLocFile l) 1 0;
1584 return (mkSrcSpan loc loc)