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 ( ModIface, 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 CmdLineOpts ( opt_SccProfilingOn )
35 import Type ( Kind, mkArrowKind, liftedTypeKind )
36 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
39 import Bag ( emptyBag )
43 import Maybes ( orElse )
49 -----------------------------------------------------------------------------
50 Conflicts: 34 shift/reduce (1.15)
52 10 for abiguity in 'if x then y else z + 1' [State 178]
53 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
54 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
56 1 for ambiguity in 'if x then y else z :: T' [State 178]
57 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
59 4 for ambiguity in 'if x then y else z -< e' [State 178]
60 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
61 There are four such operators: -<, >-, -<<, >>-
64 2 for ambiguity in 'case v of { x :: T -> T ... } ' [States 11, 253]
65 Which of these two is intended?
67 (x::T) -> T -- Rhs is T
70 (x::T -> T) -> .. -- Rhs is ...
72 8 for ambiguity in 'e :: a `b` c'. Does this mean [States 11, 253]
75 As well as `b` we can have !, QCONSYM, and CONSYM, hence 3 cases
76 Same duplication between states 11 and 253 as the previous case
78 1 for ambiguity in 'let ?x ...' [State 329]
79 the parser can't tell whether the ?x is the lhs of a normal binding or
80 an implicit binding. Fortunately resolving as shift gives it the only
81 sensible meaning, namely the lhs of an implicit binding.
83 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 382]
84 we don't know whether the '[' starts the activation or not: it
85 might be the start of the declaration with the activation being
88 6 for conflicts between `fdecl' and `fdeclDEPRECATED', [States 393,394]
89 which are resolved correctly, and moreover,
90 should go away when `fdeclDEPRECATED' is removed.
92 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 474]
93 since 'forall' is a valid variable name, we don't know whether
94 to treat a forall on the input as the beginning of a quantifier
95 or the beginning of the rule itself. Resolving to shift means
96 it's always treated as a quantifier, hence the above is disallowed.
97 This saves explicitly defining a grammar for the rule lhs that
98 doesn't include 'forall'.
100 -- ---------------------------------------------------------------------------
101 -- Adding location info
103 This is done in a stylised way using the three macros below, L0, L1
104 and LL. Each of these macros can be thought of as having type
106 L0, L1, LL :: a -> Located a
108 They each add a SrcSpan to their argument.
110 L0 adds 'noSrcSpan', used for empty productions
112 L1 for a production with a single token on the lhs. Grabs the SrcSpan
115 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
116 the first and last tokens.
118 These suffice for the majority of cases. However, we must be
119 especially careful with empty productions: LL won't work if the first
120 or last token on the lhs can represent an empty span. In these cases,
121 we have to calculate the span using more of the tokens from the lhs, eg.
123 | 'newtype' tycl_hdr '=' newconstr deriving
125 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
127 We provide comb3 and comb4 functions which are useful in such cases.
129 Be careful: there's no checking that you actually got this right, the
130 only symptom will be that the SrcSpans of your syntax will be
134 * We must expand these macros *before* running Happy, which is why this file is
135 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
137 #define L0 L noSrcSpan
138 #define L1 sL (getLoc $1)
139 #define LL sL (comb2 $1 $>)
141 -- -----------------------------------------------------------------------------
146 '_' { L _ ITunderscore } -- Haskell keywords
148 'case' { L _ ITcase }
149 'class' { L _ ITclass }
150 'data' { L _ ITdata }
151 'default' { L _ ITdefault }
152 'deriving' { L _ ITderiving }
154 'else' { L _ ITelse }
155 'hiding' { L _ IThiding }
157 'import' { L _ ITimport }
159 'infix' { L _ ITinfix }
160 'infixl' { L _ ITinfixl }
161 'infixr' { L _ ITinfixr }
162 'instance' { L _ ITinstance }
164 'module' { L _ ITmodule }
165 'newtype' { L _ ITnewtype }
167 'qualified' { L _ ITqualified }
168 'then' { L _ ITthen }
169 'type' { L _ ITtype }
170 'where' { L _ ITwhere }
171 '_scc_' { L _ ITscc } -- ToDo: remove
173 'forall' { L _ ITforall } -- GHC extension keywords
174 'foreign' { L _ ITforeign }
175 'export' { L _ ITexport }
176 'label' { L _ ITlabel }
177 'dynamic' { L _ ITdynamic }
178 'safe' { L _ ITsafe }
179 'threadsafe' { L _ ITthreadsafe }
180 'unsafe' { L _ ITunsafe }
182 'stdcall' { L _ ITstdcallconv }
183 'ccall' { L _ ITccallconv }
184 'dotnet' { L _ ITdotnet }
185 'proc' { L _ ITproc } -- for arrow notation extension
186 'rec' { L _ ITrec } -- for arrow notation extension
188 '{-# SPECIALISE' { L _ ITspecialise_prag }
189 '{-# SOURCE' { L _ ITsource_prag }
190 '{-# INLINE' { L _ ITinline_prag }
191 '{-# NOINLINE' { L _ ITnoinline_prag }
192 '{-# RULES' { L _ ITrules_prag }
193 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
194 '{-# SCC' { L _ ITscc_prag }
195 '{-# DEPRECATED' { L _ ITdeprecated_prag }
196 '{-# UNPACK' { L _ ITunpack_prag }
197 '#-}' { L _ ITclose_prag }
199 '..' { L _ ITdotdot } -- reserved symbols
201 '::' { L _ ITdcolon }
205 '<-' { L _ ITlarrow }
206 '->' { L _ ITrarrow }
209 '=>' { L _ ITdarrow }
213 '-<' { L _ ITlarrowtail } -- for arrow notation
214 '>-' { L _ ITrarrowtail } -- for arrow notation
215 '-<<' { L _ ITLarrowtail } -- for arrow notation
216 '>>-' { L _ ITRarrowtail } -- for arrow notation
219 '{' { L _ ITocurly } -- special symbols
221 '{|' { L _ ITocurlybar }
222 '|}' { L _ ITccurlybar }
223 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
224 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
227 '[:' { L _ ITopabrack }
228 ':]' { L _ ITcpabrack }
231 '(#' { L _ IToubxparen }
232 '#)' { L _ ITcubxparen }
233 '(|' { L _ IToparenbar }
234 '|)' { L _ ITcparenbar }
237 '`' { L _ ITbackquote }
239 VARID { L _ (ITvarid _) } -- identifiers
240 CONID { L _ (ITconid _) }
241 VARSYM { L _ (ITvarsym _) }
242 CONSYM { L _ (ITconsym _) }
243 QVARID { L _ (ITqvarid _) }
244 QCONID { L _ (ITqconid _) }
245 QVARSYM { L _ (ITqvarsym _) }
246 QCONSYM { L _ (ITqconsym _) }
248 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
249 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
251 CHAR { L _ (ITchar _) }
252 STRING { L _ (ITstring _) }
253 INTEGER { L _ (ITinteger _) }
254 RATIONAL { L _ (ITrational _) }
256 PRIMCHAR { L _ (ITprimchar _) }
257 PRIMSTRING { L _ (ITprimstring _) }
258 PRIMINTEGER { L _ (ITprimint _) }
259 PRIMFLOAT { L _ (ITprimfloat _) }
260 PRIMDOUBLE { L _ (ITprimdouble _) }
263 '[|' { L _ ITopenExpQuote }
264 '[p|' { L _ ITopenPatQuote }
265 '[t|' { L _ ITopenTypQuote }
266 '[d|' { L _ ITopenDecQuote }
267 '|]' { L _ ITcloseQuote }
268 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
269 '$(' { L _ ITparenEscape } -- $( exp )
270 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
271 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
273 %monad { P } { >>= } { return }
274 %lexer { lexer } { L _ ITeof }
275 %name parseModule module
276 %name parseStmt maybe_stmt
277 %name parseIdentifier identifier
278 %name parseType ctype
279 %partial parseHeader header
280 %tokentype { Located Token }
283 -----------------------------------------------------------------------------
286 -- The place for module deprecation is really too restrictive, but if it
287 -- was allowed at its natural place just before 'module', we get an ugly
288 -- s/r conflict with the second alternative. Another solution would be the
289 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
290 -- either, and DEPRECATED is only expected to be used by people who really
291 -- know what they are doing. :-)
293 module :: { Located (HsModule RdrName) }
294 : 'module' modid maybemoddeprec maybeexports 'where' body
295 {% fileSrcSpan >>= \ loc ->
296 return (L loc (HsModule (Just $2) $4 (fst $6) (snd $6) $3)) }
297 | missing_module_keyword top close
298 {% fileSrcSpan >>= \ loc ->
299 return (L loc (HsModule Nothing Nothing
300 (fst $2) (snd $2) Nothing)) }
302 missing_module_keyword :: { () }
303 : {- empty -} {% pushCurrentContext }
305 maybemoddeprec :: { Maybe DeprecTxt }
306 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
307 | {- empty -} { Nothing }
309 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
311 | vocurly top close { $2 }
313 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
314 : importdecls { (reverse $1,[]) }
315 | importdecls ';' cvtopdecls { (reverse $1,$3) }
316 | cvtopdecls { ([],$1) }
318 cvtopdecls :: { [LHsDecl RdrName] }
319 : topdecls { cvTopDecls $1 }
321 -----------------------------------------------------------------------------
322 -- Module declaration & imports only
324 header :: { Located (HsModule RdrName) }
325 : 'module' modid maybemoddeprec maybeexports 'where' header_body
326 {% fileSrcSpan >>= \ loc ->
327 return (L loc (HsModule (Just $2) $4 $6 [] $3)) }
328 | missing_module_keyword importdecls
329 {% fileSrcSpan >>= \ loc ->
330 return (L loc (HsModule Nothing Nothing $2 [] Nothing)) }
332 header_body :: { [LImportDecl RdrName] }
333 : '{' importdecls { $2 }
334 | vocurly importdecls { $2 }
336 -----------------------------------------------------------------------------
339 maybeexports :: { Maybe [LIE RdrName] }
340 : '(' exportlist ')' { Just $2 }
341 | {- empty -} { Nothing }
343 exportlist :: { [LIE RdrName] }
344 : exportlist ',' export { $3 : $1 }
345 | exportlist ',' { $1 }
349 -- No longer allow things like [] and (,,,) to be exported
350 -- They are built in syntax, always available
351 export :: { LIE RdrName }
352 : qvar { L1 (IEVar (unLoc $1)) }
353 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
354 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
355 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
356 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
357 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
359 qcnames :: { [RdrName] }
360 : qcnames ',' qcname { unLoc $3 : $1 }
361 | qcname { [unLoc $1] }
363 qcname :: { Located RdrName } -- Variable or data constructor
367 -----------------------------------------------------------------------------
368 -- Import Declarations
370 -- import decls can be *empty*, or even just a string of semicolons
371 -- whereas topdecls must contain at least one topdecl.
373 importdecls :: { [LImportDecl RdrName] }
374 : importdecls ';' importdecl { $3 : $1 }
375 | importdecls ';' { $1 }
376 | importdecl { [ $1 ] }
379 importdecl :: { LImportDecl RdrName }
380 : 'import' maybe_src optqualified modid maybeas maybeimpspec
381 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
383 maybe_src :: { IsBootInterface }
384 : '{-# SOURCE' '#-}' { True }
385 | {- empty -} { False }
387 optqualified :: { Bool }
388 : 'qualified' { True }
389 | {- empty -} { False }
391 maybeas :: { Located (Maybe Module) }
392 : 'as' modid { LL (Just (unLoc $2)) }
393 | {- empty -} { noLoc Nothing }
395 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
396 : impspec { L1 (Just (unLoc $1)) }
397 | {- empty -} { noLoc Nothing }
399 impspec :: { Located (Bool, [LIE RdrName]) }
400 : '(' exportlist ')' { LL (False, reverse $2) }
401 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
403 -----------------------------------------------------------------------------
404 -- Fixity Declarations
408 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
410 infix :: { Located FixityDirection }
411 : 'infix' { L1 InfixN }
412 | 'infixl' { L1 InfixL }
413 | 'infixr' { L1 InfixR }
415 ops :: { Located [Located RdrName] }
416 : ops ',' op { LL ($3 : unLoc $1) }
419 -----------------------------------------------------------------------------
420 -- Top-Level Declarations
422 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
423 : topdecls ';' topdecl { $1 `appOL` $3 }
424 | topdecls ';' { $1 }
427 topdecl :: { OrdList (LHsDecl RdrName) }
428 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
429 | 'instance' inst_type where
430 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
431 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
432 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
433 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
434 | '{-# DEPRECATED' deprecations '#-}' { $2 }
435 | '{-# RULES' rules '#-}' { $2 }
436 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
439 tycl_decl :: { LTyClDecl RdrName }
440 : 'type' syn_hdr '=' ctype
441 -- Note ctype, not sigtype.
442 -- We allow an explicit for-all but we don't insert one
443 -- in type Foo a = (b,b)
444 -- Instead we just say b is out of scope
445 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
447 | 'data' tycl_hdr constrs deriving
448 { L (comb4 $1 $2 $3 $4)
449 (mkTyData DataType $2 Nothing (reverse (unLoc $3)) (unLoc $4)) }
451 | 'data' tycl_hdr opt_kind_sig 'where' gadt_constrlist -- No deriving for GADTs
452 { L (comb4 $1 $2 $4 $5)
453 (mkTyData DataType $2 $3 (reverse (unLoc $5)) Nothing) }
455 | 'newtype' tycl_hdr '=' newconstr deriving
457 (mkTyData NewType $2 Nothing [$4] (unLoc $5)) }
459 | 'class' tycl_hdr fds where
461 (binds,sigs) = cvBindsAndSigs (unLoc $4)
463 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
466 opt_kind_sig :: { Maybe Kind }
468 | '::' kind { Just $2 }
470 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
471 -- We don't retain the syntax of an infix
472 -- type synonym declaration. Oh well.
473 : tycon tv_bndrs { ($1, $2) }
474 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
476 -- tycl_hdr parses the header of a type or class decl,
477 -- which takes the form
480 -- (Eq a, Ord b) => T a b
481 -- Rather a lot of inlining here, else we get reduce/reduce errors
482 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
483 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
484 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
486 -----------------------------------------------------------------------------
487 -- Nested declarations
489 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
490 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
491 | decls ';' { LL (unLoc $1) }
493 | {- empty -} { noLoc nilOL }
496 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
497 : '{' decls '}' { LL (unLoc $2) }
498 | vocurly decls close { $2 }
500 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
501 -- No implicit parameters
502 : 'where' decllist { LL (unLoc $2) }
503 | {- empty -} { noLoc nilOL }
505 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
506 : decllist { L1 [cvBindGroup (unLoc $1)] }
507 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
508 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
510 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
511 : 'where' binds { LL (unLoc $2) }
512 | {- empty -} { noLoc [] }
515 -----------------------------------------------------------------------------
516 -- Transformation Rules
518 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
519 : rules ';' rule { $1 `snocOL` $3 }
522 | {- empty -} { nilOL }
524 rule :: { LHsDecl RdrName }
525 : STRING activation rule_forall infixexp '=' exp
526 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
528 activation :: { Activation } -- Omitted means AlwaysActive
529 : {- empty -} { AlwaysActive }
530 | explicit_activation { $1 }
532 inverse_activation :: { Activation } -- Omitted means NeverActive
533 : {- empty -} { NeverActive }
534 | explicit_activation { $1 }
536 explicit_activation :: { Activation } -- In brackets
537 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
538 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
540 rule_forall :: { [RuleBndr RdrName] }
541 : 'forall' rule_var_list '.' { $2 }
544 rule_var_list :: { [RuleBndr RdrName] }
546 | rule_var rule_var_list { $1 : $2 }
548 rule_var :: { RuleBndr RdrName }
549 : varid { RuleBndr $1 }
550 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
552 -----------------------------------------------------------------------------
553 -- Deprecations (c.f. rules)
555 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
556 : deprecations ';' deprecation { $1 `appOL` $3 }
557 | deprecations ';' { $1 }
559 | {- empty -} { nilOL }
561 -- SUP: TEMPORARY HACK, not checking for `module Foo'
562 deprecation :: { OrdList (LHsDecl RdrName) }
564 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
568 -----------------------------------------------------------------------------
569 -- Foreign import and export declarations
571 -- for the time being, the following accepts foreign declarations conforming
572 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
574 -- * a flag indicates whether pre-standard declarations have been used and
575 -- triggers a deprecation warning further down the road
577 -- NB: The first two rules could be combined into one by replacing `safety1'
578 -- with `safety'. However, the combined rule conflicts with the
581 fdecl :: { LHsDecl RdrName }
582 fdecl : 'import' callconv safety1 fspec
583 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
584 | 'import' callconv fspec
585 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
587 | 'export' callconv fspec
588 {% mkExport $2 (unLoc $3) >>= return.LL }
589 -- the following syntax is DEPRECATED
590 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
591 | fdecl2DEPRECATED { L1 (unLoc $1) }
593 fdecl1DEPRECATED :: { LForeignDecl RdrName }
595 ----------- DEPRECATED label decls ------------
596 : 'label' ext_name varid '::' sigtype
597 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
598 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
600 ----------- DEPRECATED ccall/stdcall decls ------------
602 -- NB: This business with the case expression below may seem overly
603 -- complicated, but it is necessary to avoid some conflicts.
605 -- DEPRECATED variant #1: lack of a calling convention specification
607 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
609 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
611 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
612 (CFunction target)) True }
614 -- DEPRECATED variant #2: external name consists of two separate strings
615 -- (module name and function name) (import)
616 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
618 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
619 CCall cconv -> return $
621 imp = CFunction (StaticTarget (getSTRING $4))
623 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
625 -- DEPRECATED variant #3: `unsafe' after entity
626 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
628 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
629 CCall cconv -> return $
631 imp = CFunction (StaticTarget (getSTRING $3))
633 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
635 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
636 -- an explicit calling convention (import)
637 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
638 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
639 (CFunction DynamicTarget)) True }
641 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
642 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
644 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
645 CCall cconv -> return $
646 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
647 (CFunction DynamicTarget)) True }
649 -- DEPRECATED variant #6: lack of a calling convention specification
651 | 'export' {-no callconv-} ext_name varid '::' sigtype
652 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
653 defaultCCallConv)) True }
655 -- DEPRECATED variant #7: external name consists of two separate strings
656 -- (module name and function name) (export)
657 | 'export' callconv STRING STRING varid '::' sigtype
659 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
660 CCall cconv -> return $
661 LL $ ForeignExport $5 $7
662 (CExport (CExportStatic (getSTRING $4) cconv)) True }
664 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
665 -- an explicit calling convention (export)
666 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
667 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
670 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
671 | 'export' callconv 'dynamic' varid '::' sigtype
673 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
674 CCall cconv -> return $
675 LL $ ForeignImport $4 $6
676 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
678 ----------- DEPRECATED .NET decls ------------
679 -- NB: removed the .NET call declaration, as it is entirely subsumed
680 -- by the new standard FFI declarations
682 fdecl2DEPRECATED :: { LHsDecl RdrName }
684 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
685 -- left this one unchanged for the moment as type imports are not
686 -- covered currently by the FFI standard -=chak
689 callconv :: { CallConv }
690 : 'stdcall' { CCall StdCallConv }
691 | 'ccall' { CCall CCallConv }
692 | 'dotnet' { DNCall }
695 : 'unsafe' { PlayRisky }
696 | 'safe' { PlaySafe False }
697 | 'threadsafe' { PlaySafe True }
698 | {- empty -} { PlaySafe False }
700 safety1 :: { Safety }
701 : 'unsafe' { PlayRisky }
702 | 'safe' { PlaySafe False }
703 | 'threadsafe' { PlaySafe True }
704 -- only needed to avoid conflicts with the DEPRECATED rules
706 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
707 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
708 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
709 -- if the entity string is missing, it defaults to the empty string;
710 -- the meaning of an empty entity string depends on the calling
714 ext_name :: { Maybe CLabelString }
715 : STRING { Just (getSTRING $1) }
716 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
717 | {- empty -} { Nothing }
720 -----------------------------------------------------------------------------
723 opt_sig :: { Maybe (LHsType RdrName) }
724 : {- empty -} { Nothing }
725 | '::' sigtype { Just $2 }
727 opt_asig :: { Maybe (LHsType RdrName) }
728 : {- empty -} { Nothing }
729 | '::' atype { Just $2 }
731 sigtypes1 :: { [LHsType RdrName] }
733 | sigtype ',' sigtypes1 { $1 : $3 }
735 sigtype :: { LHsType RdrName }
736 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
737 -- Wrap an Implicit forall if there isn't one there already
739 sig_vars :: { Located [Located RdrName] }
740 : sig_vars ',' var { LL ($3 : unLoc $1) }
743 -----------------------------------------------------------------------------
746 strict_mark :: { Located HsBang }
747 : '!' { L1 HsStrict }
748 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
750 -- A ctype is a for-all type
751 ctype :: { LHsType RdrName }
752 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
753 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
754 -- A type of form (context => type) is an *implicit* HsForAllTy
757 -- We parse a context as a btype so that we don't get reduce/reduce
758 -- errors in ctype. The basic problem is that
760 -- looks so much like a tuple type. We can't tell until we find the =>
761 context :: { LHsContext RdrName }
762 : btype {% checkContext $1 }
764 type :: { LHsType RdrName }
765 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
768 gentype :: { LHsType RdrName }
770 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
771 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
772 | btype '->' gentype { LL $ HsFunTy $1 $3 }
774 btype :: { LHsType RdrName }
775 : btype atype { LL $ HsAppTy $1 $2 }
778 atype :: { LHsType RdrName }
779 : gtycon { L1 (HsTyVar (unLoc $1)) }
780 | tyvar { L1 (HsTyVar (unLoc $1)) }
781 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
782 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
783 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
784 | '[' type ']' { LL $ HsListTy $2 }
785 | '[:' type ':]' { LL $ HsPArrTy $2 }
786 | '(' ctype ')' { LL $ HsParTy $2 }
787 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
789 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
791 -- An inst_type is what occurs in the head of an instance decl
792 -- e.g. (Foo a, Gaz b) => Wibble a b
793 -- It's kept as a single type, with a MonoDictTy at the right
794 -- hand corner, for convenience.
795 inst_type :: { LHsType RdrName }
796 : sigtype {% checkInstType $1 }
798 inst_types1 :: { [LHsType RdrName] }
800 | inst_type ',' inst_types1 { $1 : $3 }
802 comma_types0 :: { [LHsType RdrName] }
803 : comma_types1 { $1 }
806 comma_types1 :: { [LHsType RdrName] }
808 | type ',' comma_types1 { $1 : $3 }
810 tv_bndrs :: { [LHsTyVarBndr RdrName] }
811 : tv_bndr tv_bndrs { $1 : $2 }
814 tv_bndr :: { LHsTyVarBndr RdrName }
815 : tyvar { L1 (UserTyVar (unLoc $1)) }
816 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
818 fds :: { Located [Located ([RdrName], [RdrName])] }
819 : {- empty -} { noLoc [] }
820 | '|' fds1 { LL (reverse (unLoc $2)) }
822 fds1 :: { Located [Located ([RdrName], [RdrName])] }
823 : fds1 ',' fd { LL ($3 : unLoc $1) }
826 fd :: { Located ([RdrName], [RdrName]) }
827 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
828 (reverse (unLoc $1), reverse (unLoc $3)) }
830 varids0 :: { Located [RdrName] }
831 : {- empty -} { noLoc [] }
832 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
834 -----------------------------------------------------------------------------
839 | akind '->' kind { mkArrowKind $1 $3 }
842 : '*' { liftedTypeKind }
843 | '(' kind ')' { $2 }
846 -----------------------------------------------------------------------------
847 -- Datatype declarations
849 newconstr :: { LConDecl RdrName }
850 : conid atype { LL $ ConDecl $1 [] (noLoc []) (PrefixCon [$2]) }
851 | conid '{' var '::' ctype '}'
852 { LL $ ConDecl $1 [] (noLoc []) (RecCon [($3, $5)]) }
854 gadt_constrlist :: { Located [LConDecl RdrName] }
855 : '{' gadt_constrs '}' { LL (unLoc $2) }
856 | vocurly gadt_constrs close { $2 }
858 gadt_constrs :: { Located [LConDecl RdrName] }
859 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
860 | gadt_constrs ';' { $1 }
861 | gadt_constr { L1 [$1] }
863 gadt_constr :: { LConDecl RdrName }
865 { LL (GadtDecl $1 $3) }
867 constrs :: { Located [LConDecl RdrName] }
868 : {- empty; a GHC extension -} { noLoc [] }
869 | '=' constrs1 { LL (unLoc $2) }
871 constrs1 :: { Located [LConDecl RdrName] }
872 : constrs1 '|' constr { LL ($3 : unLoc $1) }
875 constr :: { LConDecl RdrName }
876 : forall context '=>' constr_stuff
877 { let (con,details) = unLoc $4 in
878 LL (ConDecl con (unLoc $1) $2 details) }
879 | forall constr_stuff
880 { let (con,details) = unLoc $2 in
881 LL (ConDecl con (unLoc $1) (noLoc []) details) }
883 forall :: { Located [LHsTyVarBndr RdrName] }
884 : 'forall' tv_bndrs '.' { LL $2 }
885 | {- empty -} { noLoc [] }
887 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
888 -- We parse the constructor declaration
890 -- as a btype (treating C as a type constructor) and then convert C to be
891 -- a data constructor. Reason: it might continue like this:
893 -- in which case C really would be a type constructor. We can't resolve this
894 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
895 : btype {% mkPrefixCon $1 [] >>= return.LL }
896 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
897 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
898 | btype conop btype { LL ($2, InfixCon $1 $3) }
900 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
901 : fielddecl ',' fielddecls { unLoc $1 : $3 }
902 | fielddecl { [unLoc $1] }
904 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
905 : sig_vars '::' ctype { LL (reverse (unLoc $1), $3) }
907 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
908 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
909 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
910 -- We don't allow a context, but that's sorted out by the type checker.
911 deriving :: { Located (Maybe [LHsType RdrName]) }
912 : {- empty -} { noLoc Nothing }
913 | 'deriving' qtycon {% do { let { L loc tv = $2 }
914 ; p <- checkInstType (L loc (HsTyVar tv))
915 ; return (LL (Just [p])) } }
916 | 'deriving' '(' ')' { LL (Just []) }
917 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
918 -- Glasgow extension: allow partial
919 -- applications in derivings
921 -----------------------------------------------------------------------------
924 {- There's an awkward overlap with a type signature. Consider
925 f :: Int -> Int = ...rhs...
926 Then we can't tell whether it's a type signature or a value
927 definition with a result signature until we see the '='.
928 So we have to inline enough to postpone reductions until we know.
932 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
933 instead of qvar, we get another shift/reduce-conflict. Consider the
936 { (^^) :: Int->Int ; } Type signature; only var allowed
938 { (^^) :: Int->Int = ... ; } Value defn with result signature;
939 qvar allowed (because of instance decls)
941 We can't tell whether to reduce var to qvar until after we've read the signatures.
944 decl :: { Located (OrdList (LHsDecl RdrName)) }
946 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
947 return (LL $ unitOL (LL $ ValD r)) } }
949 rhs :: { Located (GRHSs RdrName) }
950 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
951 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
953 gdrhs :: { Located [LGRHS RdrName] }
954 : gdrhs gdrh { LL ($2 : unLoc $1) }
957 gdrh :: { LGRHS RdrName }
958 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
961 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
962 : infixexp '::' sigtype
963 {% do s <- checkValSig $1 $3;
964 return (LL $ unitOL (LL $ SigD s)) }
965 -- See the above notes for why we need infixexp here
966 | var ',' sig_vars '::' sigtype
967 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
968 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
970 | '{-# INLINE' activation qvar '#-}'
971 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
972 | '{-# NOINLINE' inverse_activation qvar '#-}'
973 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
974 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
975 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
977 | '{-# SPECIALISE' 'instance' inst_type '#-}'
978 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
980 -----------------------------------------------------------------------------
983 exp :: { LHsExpr RdrName }
984 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
985 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
986 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
987 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
988 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
991 infixexp :: { LHsExpr RdrName }
993 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
995 exp10 :: { LHsExpr RdrName }
996 : '\\' aexp aexps opt_asig '->' exp
997 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
998 return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
999 (GRHSs (unguardedRHS $6) []
1001 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1002 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1003 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1004 | '-' fexp { LL $ mkHsNegApp $2 }
1006 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1007 checkDo loc (unLoc $2) >>= \ stmts ->
1008 return (L loc (mkHsDo DoExpr stmts)) }
1009 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1010 checkMDo loc (unLoc $2) >>= \ stmts ->
1011 return (L loc (mkHsDo MDoExpr stmts)) }
1013 | scc_annot exp { LL $ if opt_SccProfilingOn
1014 then HsSCC (unLoc $1) $2
1017 | 'proc' aexp '->' exp
1018 {% checkPattern $2 >>= \ p ->
1019 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1020 placeHolderType undefined)) }
1021 -- TODO: is LL right here?
1023 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1024 -- hdaume: core annotation
1027 scc_annot :: { Located FastString }
1028 : '_scc_' STRING { LL $ getSTRING $2 }
1029 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1031 fexp :: { LHsExpr RdrName }
1032 : fexp aexp { LL $ HsApp $1 $2 }
1035 aexps :: { [LHsExpr RdrName] }
1036 : aexps aexp { $2 : $1 }
1037 | {- empty -} { [] }
1039 aexp :: { LHsExpr RdrName }
1040 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1041 | '~' aexp { LL $ ELazyPat $2 }
1044 aexp1 :: { LHsExpr RdrName }
1045 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1050 -- Here was the syntax for type applications that I was planning
1051 -- but there are difficulties (e.g. what order for type args)
1052 -- so it's not enabled yet.
1053 -- But this case *is* used for the left hand side of a generic definition,
1054 -- which is parsed as an expression before being munged into a pattern
1055 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1056 (sL (getLoc $3) (HsType $3)) }
1058 aexp2 :: { LHsExpr RdrName }
1059 : ipvar { L1 (HsIPVar $! unLoc $1) }
1060 | qcname { L1 (HsVar $! unLoc $1) }
1061 | literal { L1 (HsLit $! unLoc $1) }
1062 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1063 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1064 | '(' exp ')' { LL (HsPar $2) }
1065 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1066 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1067 | '[' list ']' { LL (unLoc $2) }
1068 | '[:' parr ':]' { LL (unLoc $2) }
1069 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1070 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1071 | '_' { L1 EWildPat }
1073 -- MetaHaskell Extension
1074 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1075 (L1 $ HsVar (mkUnqual varName
1076 (getTH_ID_SPLICE $1)))) } -- $x
1077 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1079 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1080 | TH_VAR_QUOTE gcon { LL $ HsBracket (VarBr (unLoc $2)) }
1081 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1082 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1083 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1084 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1085 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1086 return (LL $ HsBracket (PatBr p)) }
1087 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1089 -- arrow notation extension
1090 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1092 cmdargs :: { [LHsCmdTop RdrName] }
1093 : cmdargs acmd { $2 : $1 }
1094 | {- empty -} { [] }
1096 acmd :: { LHsCmdTop RdrName }
1097 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1099 cvtopbody :: { [LHsDecl RdrName] }
1100 : '{' cvtopdecls0 '}' { $2 }
1101 | vocurly cvtopdecls0 close { $2 }
1103 cvtopdecls0 :: { [LHsDecl RdrName] }
1104 : {- empty -} { [] }
1107 texps :: { [LHsExpr RdrName] }
1108 : texps ',' exp { $3 : $1 }
1112 -----------------------------------------------------------------------------
1115 -- The rules below are little bit contorted to keep lexps left-recursive while
1116 -- avoiding another shift/reduce-conflict.
1118 list :: { LHsExpr RdrName }
1119 : exp { L1 $ ExplicitList placeHolderType [$1] }
1120 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1121 | exp '..' { LL $ ArithSeqIn (From $1) }
1122 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1123 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1124 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1125 | exp pquals { LL $ mkHsDo ListComp
1126 (reverse (L (getLoc $1) (ResultStmt $1) :
1129 lexps :: { Located [LHsExpr RdrName] }
1130 : lexps ',' exp { LL ($3 : unLoc $1) }
1131 | exp ',' exp { LL [$3,$1] }
1133 -----------------------------------------------------------------------------
1134 -- List Comprehensions
1136 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1137 -- or a reversed list of Stmts
1138 : pquals1 { case unLoc $1 of
1140 qss -> L1 [L1 (ParStmt stmtss)]
1142 stmtss = [ (reverse qs, undefined)
1146 pquals1 :: { Located [[LStmt RdrName]] }
1147 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1148 | '|' quals { L (getLoc $2) [unLoc $2] }
1150 quals :: { Located [LStmt RdrName] }
1151 : quals ',' qual { LL ($3 : unLoc $1) }
1154 -----------------------------------------------------------------------------
1155 -- Parallel array expressions
1157 -- The rules below are little bit contorted; see the list case for details.
1158 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1159 -- Moreover, we allow explicit arrays with no element (represented by the nil
1160 -- constructor in the list case).
1162 parr :: { LHsExpr RdrName }
1163 : { noLoc (ExplicitPArr placeHolderType []) }
1164 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1165 | lexps { L1 $ ExplicitPArr placeHolderType
1166 (reverse (unLoc $1)) }
1167 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1168 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1169 | exp pquals { LL $ mkHsDo PArrComp
1170 (reverse (L (getLoc $1) (ResultStmt $1) :
1174 -- We are reusing `lexps' and `pquals' from the list case.
1176 -----------------------------------------------------------------------------
1177 -- Case alternatives
1179 altslist :: { Located [LMatch RdrName] }
1180 : '{' alts '}' { LL (reverse (unLoc $2)) }
1181 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1183 alts :: { Located [LMatch RdrName] }
1184 : alts1 { L1 (unLoc $1) }
1185 | ';' alts { LL (unLoc $2) }
1187 alts1 :: { Located [LMatch RdrName] }
1188 : alts1 ';' alt { LL ($3 : unLoc $1) }
1189 | alts1 ';' { LL (unLoc $1) }
1192 alt :: { LMatch RdrName }
1193 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1194 return (LL (Match [p] $2 (unLoc $3))) }
1196 alt_rhs :: { Located (GRHSs RdrName) }
1197 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1199 ralt :: { Located [LGRHS RdrName] }
1200 : '->' exp { LL (unguardedRHS $2) }
1201 | gdpats { L1 (reverse (unLoc $1)) }
1203 gdpats :: { Located [LGRHS RdrName] }
1204 : gdpats gdpat { LL ($2 : unLoc $1) }
1207 gdpat :: { LGRHS RdrName }
1208 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1209 in LL $ GRHS (reverse (r : unLoc $2)) }
1211 -----------------------------------------------------------------------------
1212 -- Statement sequences
1214 stmtlist :: { Located [LStmt RdrName] }
1215 : '{' stmts '}' { LL (unLoc $2) }
1216 | vocurly stmts close { $2 }
1218 -- do { ;; s ; s ; ; s ;; }
1219 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1220 -- here, because we need too much lookahead if we see do { e ; }
1221 -- So we use ExprStmts throughout, and switch the last one over
1222 -- in ParseUtils.checkDo instead
1223 stmts :: { Located [LStmt RdrName] }
1224 : stmt stmts_help { LL ($1 : unLoc $2) }
1225 | ';' stmts { LL (unLoc $2) }
1226 | {- empty -} { noLoc [] }
1228 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1229 : ';' stmts { LL (unLoc $2) }
1230 | {- empty -} { noLoc [] }
1232 -- For typing stmts at the GHCi prompt, where
1233 -- the input may consist of just comments.
1234 maybe_stmt :: { Maybe (LStmt RdrName) }
1236 | {- nothing -} { Nothing }
1238 stmt :: { LStmt RdrName }
1240 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1241 return (LL $ BindStmt p $1) }
1242 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1244 qual :: { LStmt RdrName }
1245 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1246 return (LL $ BindStmt p $3) }
1247 | exp { L1 $ ExprStmt $1 placeHolderType }
1248 | 'let' binds { LL $ LetStmt (unLoc $2) }
1250 -----------------------------------------------------------------------------
1251 -- Record Field Update/Construction
1253 fbinds :: { HsRecordBinds RdrName }
1255 | {- empty -} { [] }
1257 fbinds1 :: { HsRecordBinds RdrName }
1258 : fbinds1 ',' fbind { $3 : $1 }
1261 fbind :: { (Located RdrName, LHsExpr RdrName) }
1262 : qvar '=' exp { ($1,$3) }
1264 -----------------------------------------------------------------------------
1265 -- Implicit Parameter Bindings
1267 dbinds :: { Located [LIPBind RdrName] }
1268 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1269 | dbinds ';' { LL (unLoc $1) }
1271 -- | {- empty -} { [] }
1273 dbind :: { LIPBind RdrName }
1274 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1276 -----------------------------------------------------------------------------
1277 -- Variables, Constructors and Operators.
1279 identifier :: { Located RdrName }
1285 depreclist :: { Located [RdrName] }
1286 depreclist : deprec_var { L1 [unLoc $1] }
1287 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1289 deprec_var :: { Located RdrName }
1290 deprec_var : var { $1 }
1293 gcon :: { Located RdrName } -- Data constructor namespace
1294 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1296 -- the case of '[:' ':]' is part of the production `parr'
1298 sysdcon :: { Located DataCon } -- Wired in data constructors
1299 : '(' ')' { LL unitDataCon }
1300 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1301 | '[' ']' { LL nilDataCon }
1303 var :: { Located RdrName }
1305 | '(' varsym ')' { LL (unLoc $2) }
1307 qvar :: { Located RdrName }
1309 | '(' varsym ')' { LL (unLoc $2) }
1310 | '(' qvarsym1 ')' { LL (unLoc $2) }
1311 -- We've inlined qvarsym here so that the decision about
1312 -- whether it's a qvar or a var can be postponed until
1313 -- *after* we see the close paren.
1315 ipvar :: { Located (IPName RdrName) }
1316 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1317 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1319 qcon :: { Located RdrName }
1321 | '(' qconsym ')' { LL (unLoc $2) }
1323 varop :: { Located RdrName }
1325 | '`' varid '`' { LL (unLoc $2) }
1327 qvarop :: { Located RdrName }
1329 | '`' qvarid '`' { LL (unLoc $2) }
1331 qvaropm :: { Located RdrName }
1332 : qvarsym_no_minus { $1 }
1333 | '`' qvarid '`' { LL (unLoc $2) }
1335 conop :: { Located RdrName }
1337 | '`' conid '`' { LL (unLoc $2) }
1339 qconop :: { Located RdrName }
1341 | '`' qconid '`' { LL (unLoc $2) }
1343 -----------------------------------------------------------------------------
1344 -- Type constructors
1346 gtycon :: { Located RdrName } -- A "general" qualified tycon
1348 | '(' ')' { LL $ getRdrName unitTyCon }
1349 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1350 | '(' '->' ')' { LL $ getRdrName funTyCon }
1351 | '[' ']' { LL $ listTyCon_RDR }
1352 | '[:' ':]' { LL $ parrTyCon_RDR }
1354 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1356 | '(' qtyconsym ')' { LL (unLoc $2) }
1358 qtyconop :: { Located RdrName } -- Qualified or unqualified
1360 | '`' qtycon '`' { LL (unLoc $2) }
1362 tyconop :: { Located RdrName } -- Unqualified
1364 | '`' tycon '`' { LL (unLoc $2) }
1366 qtycon :: { Located RdrName } -- Qualified or unqualified
1367 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1370 tycon :: { Located RdrName } -- Unqualified
1371 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1373 qtyconsym :: { Located RdrName }
1374 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1377 tyconsym :: { Located RdrName }
1378 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1380 -----------------------------------------------------------------------------
1383 op :: { Located RdrName } -- used in infix decls
1387 qop :: { LHsExpr RdrName } -- used in sections
1388 : qvarop { L1 $ HsVar (unLoc $1) }
1389 | qconop { L1 $ HsVar (unLoc $1) }
1391 qopm :: { LHsExpr RdrName } -- used in sections
1392 : qvaropm { L1 $ HsVar (unLoc $1) }
1393 | qconop { L1 $ HsVar (unLoc $1) }
1395 -----------------------------------------------------------------------------
1398 qvarid :: { Located RdrName }
1400 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1402 varid :: { Located RdrName }
1403 : varid_no_unsafe { $1 }
1404 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1405 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1406 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1408 varid_no_unsafe :: { Located RdrName }
1409 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1410 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1411 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1413 tyvar :: { Located RdrName }
1414 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1415 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1416 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1417 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1418 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1420 -- These special_ids are treated as keywords in various places,
1421 -- but as ordinary ids elsewhere. 'special_id' collects all these
1422 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1423 special_id :: { Located UserFS }
1425 : 'as' { L1 FSLIT("as") }
1426 | 'qualified' { L1 FSLIT("qualified") }
1427 | 'hiding' { L1 FSLIT("hiding") }
1428 | 'export' { L1 FSLIT("export") }
1429 | 'label' { L1 FSLIT("label") }
1430 | 'dynamic' { L1 FSLIT("dynamic") }
1431 | 'stdcall' { L1 FSLIT("stdcall") }
1432 | 'ccall' { L1 FSLIT("ccall") }
1434 -----------------------------------------------------------------------------
1437 qvarsym :: { Located RdrName }
1441 qvarsym_no_minus :: { Located RdrName }
1442 : varsym_no_minus { $1 }
1445 qvarsym1 :: { Located RdrName }
1446 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1448 varsym :: { Located RdrName }
1449 : varsym_no_minus { $1 }
1450 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1452 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1453 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1454 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1457 -- See comments with special_id
1458 special_sym :: { Located UserFS }
1459 special_sym : '!' { L1 FSLIT("!") }
1460 | '.' { L1 FSLIT(".") }
1461 | '*' { L1 FSLIT("*") }
1463 -----------------------------------------------------------------------------
1464 -- Data constructors
1466 qconid :: { Located RdrName } -- Qualified or unqualified
1468 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1470 conid :: { Located RdrName }
1471 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1473 qconsym :: { Located RdrName } -- Qualified or unqualified
1475 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1477 consym :: { Located RdrName }
1478 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1480 -- ':' means only list cons
1481 | ':' { L1 $ consDataCon_RDR }
1484 -----------------------------------------------------------------------------
1487 literal :: { Located HsLit }
1488 : CHAR { L1 $ HsChar $ getCHAR $1 }
1489 | STRING { L1 $ HsString $ getSTRING $1 }
1490 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1491 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1492 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1493 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1494 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1496 -----------------------------------------------------------------------------
1500 : vccurly { () } -- context popped in lexer.
1501 | error {% popContext }
1503 -----------------------------------------------------------------------------
1504 -- Miscellaneous (mostly renamings)
1506 modid :: { Located Module }
1507 : CONID { L1 $ mkModuleFS (getCONID $1) }
1508 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1511 (unpackFS mod ++ '.':unpackFS c))
1515 : commas ',' { $1 + 1 }
1518 -----------------------------------------------------------------------------
1522 happyError = srcParseFail
1524 getVARID (L _ (ITvarid x)) = x
1525 getCONID (L _ (ITconid x)) = x
1526 getVARSYM (L _ (ITvarsym x)) = x
1527 getCONSYM (L _ (ITconsym x)) = x
1528 getQVARID (L _ (ITqvarid x)) = x
1529 getQCONID (L _ (ITqconid x)) = x
1530 getQVARSYM (L _ (ITqvarsym x)) = x
1531 getQCONSYM (L _ (ITqconsym x)) = x
1532 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1533 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1534 getCHAR (L _ (ITchar x)) = x
1535 getSTRING (L _ (ITstring x)) = x
1536 getINTEGER (L _ (ITinteger x)) = x
1537 getRATIONAL (L _ (ITrational x)) = x
1538 getPRIMCHAR (L _ (ITprimchar x)) = x
1539 getPRIMSTRING (L _ (ITprimstring x)) = x
1540 getPRIMINTEGER (L _ (ITprimint x)) = x
1541 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1542 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1543 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1545 -- Utilities for combining source spans
1546 comb2 :: Located a -> Located b -> SrcSpan
1549 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1550 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1552 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1553 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1554 combineSrcSpans (getLoc c) (getLoc d)
1556 -- strict constructor version:
1558 sL :: SrcSpan -> a -> Located a
1559 sL span a = span `seq` L span a
1561 -- Make a source location for the file. We're a bit lazy here and just
1562 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1563 -- try to find the span of the whole file (ToDo).
1564 fileSrcSpan :: P SrcSpan
1567 let loc = mkSrcLoc (srcLocFile l) 1 0;
1568 return (mkSrcSpan loc loc)