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: 29 shift/reduce, [SDM 19/9/2002]
51 10 for abiguity in 'if x then y else z + 1' [State 136]
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 with ?x=3' [State 136]
56 (shift parses as 'if x then y else (z with ?x=3)'
58 1 for ambiguity in 'if x then y else z :: T' [State 136]
59 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
61 4 for ambiguity in 'if x then y else z -< e'
62 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
64 8 for ambiguity in 'e :: a `b` c'. Does this mean [States 160,246]
68 1 for ambiguity in 'let ?x ...' [State 268]
69 the parser can't tell whether the ?x is the lhs of a normal binding or
70 an implicit binding. Fortunately resolving as shift gives it the only
71 sensible meaning, namely the lhs of an implicit binding.
73 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 332]
74 we don't know whether the '[' starts the activation or not: it
75 might be the start of the declaration with the activation being
78 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 394]
79 since 'forall' is a valid variable name, we don't know whether
80 to treat a forall on the input as the beginning of a quantifier
81 or the beginning of the rule itself. Resolving to shift means
82 it's always treated as a quantifier, hence the above is disallowed.
83 This saves explicitly defining a grammar for the rule lhs that
84 doesn't include 'forall'.
86 6 for conflicts between `fdecl' and `fdeclDEPRECATED', [States 384,385]
87 which are resolved correctly, and moreover,
88 should go away when `fdeclDEPRECATED' is removed.
90 -- ---------------------------------------------------------------------------
91 -- Adding location info
93 This is done in a stylised way using the three macros below, L0, L1
94 and LL. Each of these macros can be thought of as having type
96 L0, L1, LL :: a -> Located a
98 They each add a SrcSpan to their argument.
100 L0 adds 'noSrcSpan', used for empty productions
102 L1 for a production with a single token on the lhs. Grabs the SrcSpan
105 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
106 the first and last tokens.
108 These suffice for the majority of cases. However, we must be
109 especially careful with empty productions: LL won't work if the first
110 or last token on the lhs can represent an empty span. In these cases,
111 we have to calculate the span using more of the tokens from the lhs, eg.
113 | 'newtype' tycl_hdr '=' newconstr deriving
115 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
117 We provide comb3 and comb4 functions which are useful in such cases.
119 Be careful: there's no checking that you actually got this right, the
120 only symptom will be that the SrcSpans of your syntax will be
124 * We must expand these macros *before* running Happy, which is why this file is
125 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
127 #define L0 L noSrcSpan
128 #define L1 sL (getLoc $1)
129 #define LL sL (comb2 $1 $>)
131 -- -----------------------------------------------------------------------------
136 '_' { L _ ITunderscore } -- Haskell keywords
138 'case' { L _ ITcase }
139 'class' { L _ ITclass }
140 'data' { L _ ITdata }
141 'default' { L _ ITdefault }
142 'deriving' { L _ ITderiving }
144 'else' { L _ ITelse }
145 'hiding' { L _ IThiding }
147 'import' { L _ ITimport }
149 'infix' { L _ ITinfix }
150 'infixl' { L _ ITinfixl }
151 'infixr' { L _ ITinfixr }
152 'instance' { L _ ITinstance }
154 'module' { L _ ITmodule }
155 'newtype' { L _ ITnewtype }
157 'qualified' { L _ ITqualified }
158 'then' { L _ ITthen }
159 'type' { L _ ITtype }
160 'where' { L _ ITwhere }
161 '_scc_' { L _ ITscc } -- ToDo: remove
163 'forall' { L _ ITforall } -- GHC extension keywords
164 'foreign' { L _ ITforeign }
165 'export' { L _ ITexport }
166 'label' { L _ ITlabel }
167 'dynamic' { L _ ITdynamic }
168 'safe' { L _ ITsafe }
169 'threadsafe' { L _ ITthreadsafe }
170 'unsafe' { L _ ITunsafe }
172 'stdcall' { L _ ITstdcallconv }
173 'ccall' { L _ ITccallconv }
174 'dotnet' { L _ ITdotnet }
175 'proc' { L _ ITproc } -- for arrow notation extension
176 'rec' { L _ ITrec } -- for arrow notation extension
178 '{-# SPECIALISE' { L _ ITspecialise_prag }
179 '{-# SOURCE' { L _ ITsource_prag }
180 '{-# INLINE' { L _ ITinline_prag }
181 '{-# NOINLINE' { L _ ITnoinline_prag }
182 '{-# RULES' { L _ ITrules_prag }
183 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
184 '{-# SCC' { L _ ITscc_prag }
185 '{-# DEPRECATED' { L _ ITdeprecated_prag }
186 '{-# UNPACK' { L _ ITunpack_prag }
187 '#-}' { L _ ITclose_prag }
189 '..' { L _ ITdotdot } -- reserved symbols
191 '::' { L _ ITdcolon }
195 '<-' { L _ ITlarrow }
196 '->' { L _ ITrarrow }
199 '=>' { L _ ITdarrow }
203 '-<' { L _ ITlarrowtail } -- for arrow notation
204 '>-' { L _ ITrarrowtail } -- for arrow notation
205 '-<<' { L _ ITLarrowtail } -- for arrow notation
206 '>>-' { L _ ITRarrowtail } -- for arrow notation
209 '{' { L _ ITocurly } -- special symbols
211 '{|' { L _ ITocurlybar }
212 '|}' { L _ ITccurlybar }
213 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
214 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
217 '[:' { L _ ITopabrack }
218 ':]' { L _ ITcpabrack }
221 '(#' { L _ IToubxparen }
222 '#)' { L _ ITcubxparen }
223 '(|' { L _ IToparenbar }
224 '|)' { L _ ITcparenbar }
227 '`' { L _ ITbackquote }
229 VARID { L _ (ITvarid _) } -- identifiers
230 CONID { L _ (ITconid _) }
231 VARSYM { L _ (ITvarsym _) }
232 CONSYM { L _ (ITconsym _) }
233 QVARID { L _ (ITqvarid _) }
234 QCONID { L _ (ITqconid _) }
235 QVARSYM { L _ (ITqvarsym _) }
236 QCONSYM { L _ (ITqconsym _) }
238 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
239 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
241 CHAR { L _ (ITchar _) }
242 STRING { L _ (ITstring _) }
243 INTEGER { L _ (ITinteger _) }
244 RATIONAL { L _ (ITrational _) }
246 PRIMCHAR { L _ (ITprimchar _) }
247 PRIMSTRING { L _ (ITprimstring _) }
248 PRIMINTEGER { L _ (ITprimint _) }
249 PRIMFLOAT { L _ (ITprimfloat _) }
250 PRIMDOUBLE { L _ (ITprimdouble _) }
253 '[|' { L _ ITopenExpQuote }
254 '[p|' { L _ ITopenPatQuote }
255 '[t|' { L _ ITopenTypQuote }
256 '[d|' { L _ ITopenDecQuote }
257 '|]' { L _ ITcloseQuote }
258 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
259 '$(' { L _ ITparenEscape } -- $( exp )
260 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
261 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
263 %monad { P } { >>= } { return }
264 %lexer { lexer } { L _ ITeof }
265 %name parseModule module
266 %name parseStmt maybe_stmt
267 %name parseIdentifier identifier
268 %name parseIface iface
269 %name parseType ctype
270 %tokentype { Located Token }
273 -----------------------------------------------------------------------------
276 -- The place for module deprecation is really too restrictive, but if it
277 -- was allowed at its natural place just before 'module', we get an ugly
278 -- s/r conflict with the second alternative. Another solution would be the
279 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
280 -- either, and DEPRECATED is only expected to be used by people who really
281 -- know what they are doing. :-)
283 module :: { Located (HsModule RdrName) }
284 : 'module' modid maybemoddeprec maybeexports 'where' body
285 {% fileSrcSpan >>= \ loc ->
286 return (L loc (HsModule (Just (L (getLoc $2)
287 (mkHomeModule (unLoc $2))))
288 $4 (fst $6) (snd $6) $3)) }
289 | missing_module_keyword top close
290 {% fileSrcSpan >>= \ loc ->
291 return (L loc (HsModule Nothing Nothing
292 (fst $2) (snd $2) Nothing)) }
294 missing_module_keyword :: { () }
295 : {- empty -} {% pushCurrentContext }
297 maybemoddeprec :: { Maybe DeprecTxt }
298 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
299 | {- empty -} { Nothing }
301 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
303 | vocurly top close { $2 }
305 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
306 : importdecls { (reverse $1,[]) }
307 | importdecls ';' cvtopdecls { (reverse $1,$3) }
308 | cvtopdecls { ([],$1) }
310 cvtopdecls :: { [LHsDecl RdrName] }
311 : topdecls { cvTopDecls $1 }
313 -----------------------------------------------------------------------------
314 -- Interfaces (.hi-boot files)
316 iface :: { ModIface }
317 : 'module' modid 'where' ifacebody { mkBootIface (unLoc $2) $4 }
319 ifacebody :: { [HsDecl RdrName] }
320 : '{' ifacedecls '}' { $2 }
321 | vocurly ifacedecls close { $2 }
323 ifacedecls :: { [HsDecl RdrName] }
324 : ifacedecl ';' ifacedecls { $1 : $3 }
325 | ';' ifacedecls { $2 }
329 ifacedecl :: { HsDecl RdrName }
332 | 'type' syn_hdr '=' ctype
333 { let (tc,tvs) = $2 in TyClD (TySynonym tc tvs $4) }
334 | 'data' tycl_hdr constrs -- No deriving in hi-boot
335 { TyClD (mkTyData DataType $2 Nothing (reverse (unLoc $3)) Nothing) }
336 | 'data' tycl_hdr 'where' gadt_constrlist
337 { TyClD (mkTyData DataType $2 Nothing (reverse (unLoc $4)) Nothing) }
338 | 'newtype' tycl_hdr -- Constructor is optional
339 { TyClD (mkTyData NewType $2 Nothing [] Nothing) }
340 | 'newtype' tycl_hdr '=' newconstr
341 { TyClD (mkTyData NewType $2 Nothing [$4] Nothing) }
342 | 'class' tycl_hdr fds
343 { TyClD (mkClassDecl (unLoc $2) (unLoc $3) [] emptyBag) }
345 -----------------------------------------------------------------------------
348 maybeexports :: { Maybe [LIE RdrName] }
349 : '(' exportlist ')' { Just $2 }
350 | {- empty -} { Nothing }
352 exportlist :: { [LIE RdrName] }
353 : exportlist ',' export { $3 : $1 }
354 | exportlist ',' { $1 }
358 -- No longer allow things like [] and (,,,) to be exported
359 -- They are built in syntax, always available
360 export :: { LIE RdrName }
361 : qvar { L1 (IEVar (unLoc $1)) }
362 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
363 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
364 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
365 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
366 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
368 qcnames :: { [RdrName] }
369 : qcnames ',' qcname { unLoc $3 : $1 }
370 | qcname { [unLoc $1] }
372 qcname :: { Located RdrName } -- Variable or data constructor
376 -----------------------------------------------------------------------------
377 -- Import Declarations
379 -- import decls can be *empty*, or even just a string of semicolons
380 -- whereas topdecls must contain at least one topdecl.
382 importdecls :: { [LImportDecl RdrName] }
383 : importdecls ';' importdecl { $3 : $1 }
384 | importdecls ';' { $1 }
385 | importdecl { [ $1 ] }
388 importdecl :: { LImportDecl RdrName }
389 : 'import' maybe_src optqualified modid maybeas maybeimpspec
390 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
392 maybe_src :: { IsBootInterface }
393 : '{-# SOURCE' '#-}' { True }
394 | {- empty -} { False }
396 optqualified :: { Bool }
397 : 'qualified' { True }
398 | {- empty -} { False }
400 maybeas :: { Located (Maybe ModuleName) }
401 : 'as' modid { LL (Just (unLoc $2)) }
402 | {- empty -} { noLoc Nothing }
404 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
405 : impspec { L1 (Just (unLoc $1)) }
406 | {- empty -} { noLoc Nothing }
408 impspec :: { Located (Bool, [LIE RdrName]) }
409 : '(' exportlist ')' { LL (False, reverse $2) }
410 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
412 -----------------------------------------------------------------------------
413 -- Fixity Declarations
417 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
419 infix :: { Located FixityDirection }
420 : 'infix' { L1 InfixN }
421 | 'infixl' { L1 InfixL }
422 | 'infixr' { L1 InfixR }
424 ops :: { Located [Located RdrName] }
425 : ops ',' op { LL ($3 : unLoc $1) }
428 -----------------------------------------------------------------------------
429 -- Top-Level Declarations
431 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
432 : topdecls ';' topdecl { $1 `appOL` $3 }
433 | topdecls ';' { $1 }
436 topdecl :: { OrdList (LHsDecl RdrName) }
437 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
438 | 'instance' inst_type where
439 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
440 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
441 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
442 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
443 | '{-# DEPRECATED' deprecations '#-}' { $2 }
444 | '{-# RULES' rules '#-}' { $2 }
445 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
448 tycl_decl :: { LTyClDecl RdrName }
449 : 'type' syn_hdr '=' ctype
450 -- Note ctype, not sigtype.
451 -- We allow an explicit for-all but we don't insert one
452 -- in type Foo a = (b,b)
453 -- Instead we just say b is out of scope
454 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
456 | 'data' tycl_hdr constrs deriving
457 { L (comb4 $1 $2 $3 $4)
458 (mkTyData DataType $2 Nothing (reverse (unLoc $3)) (unLoc $4)) }
460 | 'data' tycl_hdr opt_kind_sig 'where' gadt_constrlist -- No deriving for GADTs
461 { L (comb4 $1 $2 $4 $5)
462 (mkTyData DataType $2 $3 (reverse (unLoc $5)) Nothing) }
464 | 'newtype' tycl_hdr '=' newconstr deriving
466 (mkTyData NewType $2 Nothing [$4] (unLoc $5)) }
468 | 'class' tycl_hdr fds where
470 (binds,sigs) = cvBindsAndSigs (unLoc $4)
472 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
475 opt_kind_sig :: { Maybe Kind }
477 | '::' kind { Just $2 }
479 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
480 -- We don't retain the syntax of an infix
481 -- type synonym declaration. Oh well.
482 : tycon tv_bndrs { ($1, $2) }
483 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
485 -- tycl_hdr parses the header of a type or class decl,
486 -- which takes the form
489 -- (Eq a, Ord b) => T a b
490 -- Rather a lot of inlining here, else we get reduce/reduce errors
491 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
492 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
493 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
495 -----------------------------------------------------------------------------
496 -- Nested declarations
498 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
499 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
500 | decls ';' { LL (unLoc $1) }
502 | {- empty -} { noLoc nilOL }
505 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
506 : '{' decls '}' { LL (unLoc $2) }
507 | vocurly decls close { $2 }
509 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
510 -- No implicit parameters
511 : 'where' decllist { LL (unLoc $2) }
512 | {- empty -} { noLoc nilOL }
514 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
515 : decllist { L1 [cvBindGroup (unLoc $1)] }
516 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
517 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
519 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
520 : 'where' binds { LL (unLoc $2) }
521 | {- empty -} { noLoc [] }
524 -----------------------------------------------------------------------------
525 -- Transformation Rules
527 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
528 : rules ';' rule { $1 `snocOL` $3 }
531 | {- empty -} { nilOL }
533 rule :: { LHsDecl RdrName }
534 : STRING activation rule_forall infixexp '=' exp
535 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
537 activation :: { Activation } -- Omitted means AlwaysActive
538 : {- empty -} { AlwaysActive }
539 | explicit_activation { $1 }
541 inverse_activation :: { Activation } -- Omitted means NeverActive
542 : {- empty -} { NeverActive }
543 | explicit_activation { $1 }
545 explicit_activation :: { Activation } -- In brackets
546 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
547 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
549 rule_forall :: { [RuleBndr RdrName] }
550 : 'forall' rule_var_list '.' { $2 }
553 rule_var_list :: { [RuleBndr RdrName] }
555 | rule_var rule_var_list { $1 : $2 }
557 rule_var :: { RuleBndr RdrName }
558 : varid { RuleBndr $1 }
559 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
561 -----------------------------------------------------------------------------
562 -- Deprecations (c.f. rules)
564 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
565 : deprecations ';' deprecation { $1 `appOL` $3 }
566 | deprecations ';' { $1 }
568 | {- empty -} { nilOL }
570 -- SUP: TEMPORARY HACK, not checking for `module Foo'
571 deprecation :: { OrdList (LHsDecl RdrName) }
573 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
577 -----------------------------------------------------------------------------
578 -- Foreign import and export declarations
580 -- for the time being, the following accepts foreign declarations conforming
581 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
583 -- * a flag indicates whether pre-standard declarations have been used and
584 -- triggers a deprecation warning further down the road
586 -- NB: The first two rules could be combined into one by replacing `safety1'
587 -- with `safety'. However, the combined rule conflicts with the
590 fdecl :: { LHsDecl RdrName }
591 fdecl : 'import' callconv safety1 fspec
592 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
593 | 'import' callconv fspec
594 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
596 | 'export' callconv fspec
597 {% mkExport $2 (unLoc $3) >>= return.LL }
598 -- the following syntax is DEPRECATED
599 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
600 | fdecl2DEPRECATED { L1 (unLoc $1) }
602 fdecl1DEPRECATED :: { LForeignDecl RdrName }
604 ----------- DEPRECATED label decls ------------
605 : 'label' ext_name varid '::' sigtype
606 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
607 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
609 ----------- DEPRECATED ccall/stdcall decls ------------
611 -- NB: This business with the case expression below may seem overly
612 -- complicated, but it is necessary to avoid some conflicts.
614 -- DEPRECATED variant #1: lack of a calling convention specification
616 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
618 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
620 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
621 (CFunction target)) True }
623 -- DEPRECATED variant #2: external name consists of two separate strings
624 -- (module name and function name) (import)
625 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
627 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
628 CCall cconv -> return $
630 imp = CFunction (StaticTarget (getSTRING $4))
632 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
634 -- DEPRECATED variant #3: `unsafe' after entity
635 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
637 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
638 CCall cconv -> return $
640 imp = CFunction (StaticTarget (getSTRING $3))
642 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
644 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
645 -- an explicit calling convention (import)
646 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
647 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
648 (CFunction DynamicTarget)) True }
650 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
651 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
653 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
654 CCall cconv -> return $
655 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
656 (CFunction DynamicTarget)) True }
658 -- DEPRECATED variant #6: lack of a calling convention specification
660 | 'export' {-no callconv-} ext_name varid '::' sigtype
661 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
662 defaultCCallConv)) True }
664 -- DEPRECATED variant #7: external name consists of two separate strings
665 -- (module name and function name) (export)
666 | 'export' callconv STRING STRING varid '::' sigtype
668 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
669 CCall cconv -> return $
670 LL $ ForeignExport $5 $7
671 (CExport (CExportStatic (getSTRING $4) cconv)) True }
673 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
674 -- an explicit calling convention (export)
675 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
676 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
679 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
680 | 'export' callconv 'dynamic' varid '::' sigtype
682 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
683 CCall cconv -> return $
684 LL $ ForeignImport $4 $6
685 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
687 ----------- DEPRECATED .NET decls ------------
688 -- NB: removed the .NET call declaration, as it is entirely subsumed
689 -- by the new standard FFI declarations
691 fdecl2DEPRECATED :: { LHsDecl RdrName }
693 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
694 -- left this one unchanged for the moment as type imports are not
695 -- covered currently by the FFI standard -=chak
698 callconv :: { CallConv }
699 : 'stdcall' { CCall StdCallConv }
700 | 'ccall' { CCall CCallConv }
701 | 'dotnet' { DNCall }
704 : 'unsafe' { PlayRisky }
705 | 'safe' { PlaySafe False }
706 | 'threadsafe' { PlaySafe True }
707 | {- empty -} { PlaySafe False }
709 safety1 :: { Safety }
710 : 'unsafe' { PlayRisky }
711 | 'safe' { PlaySafe False }
712 | 'threadsafe' { PlaySafe True }
713 -- only needed to avoid conflicts with the DEPRECATED rules
715 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
716 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
717 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
718 -- if the entity string is missing, it defaults to the empty string;
719 -- the meaning of an empty entity string depends on the calling
723 ext_name :: { Maybe CLabelString }
724 : STRING { Just (getSTRING $1) }
725 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
726 | {- empty -} { Nothing }
729 -----------------------------------------------------------------------------
732 opt_sig :: { Maybe (LHsType RdrName) }
733 : {- empty -} { Nothing }
734 | '::' sigtype { Just $2 }
736 opt_asig :: { Maybe (LHsType RdrName) }
737 : {- empty -} { Nothing }
738 | '::' atype { Just $2 }
740 sigtypes1 :: { [LHsType RdrName] }
742 | sigtype ',' sigtypes1 { $1 : $3 }
744 sigtype :: { LHsType RdrName }
745 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
746 -- Wrap an Implicit forall if there isn't one there already
748 sig_vars :: { Located [Located RdrName] }
749 : sig_vars ',' var { LL ($3 : unLoc $1) }
752 -----------------------------------------------------------------------------
755 strict_mark :: { Located HsBang }
756 : '!' { L1 HsStrict }
757 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
759 -- A ctype is a for-all type
760 ctype :: { LHsType RdrName }
761 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
762 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
763 -- A type of form (context => type) is an *implicit* HsForAllTy
766 -- We parse a context as a btype so that we don't get reduce/reduce
767 -- errors in ctype. The basic problem is that
769 -- looks so much like a tuple type. We can't tell until we find the =>
770 context :: { LHsContext RdrName }
771 : btype {% checkContext $1 }
773 type :: { LHsType RdrName }
774 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
777 gentype :: { LHsType RdrName }
779 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
780 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
781 | btype '->' gentype { LL $ HsFunTy $1 $3 }
783 btype :: { LHsType RdrName }
784 : btype atype { LL $ HsAppTy $1 $2 }
787 atype :: { LHsType RdrName }
788 : gtycon { L1 (HsTyVar (unLoc $1)) }
789 | tyvar { L1 (HsTyVar (unLoc $1)) }
790 | strict_mark atype { LL (HsBangTy (unLoc $1) $2) }
791 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
792 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
793 | '[' type ']' { LL $ HsListTy $2 }
794 | '[:' type ':]' { LL $ HsPArrTy $2 }
795 | '(' ctype ')' { LL $ HsParTy $2 }
796 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
798 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
800 -- An inst_type is what occurs in the head of an instance decl
801 -- e.g. (Foo a, Gaz b) => Wibble a b
802 -- It's kept as a single type, with a MonoDictTy at the right
803 -- hand corner, for convenience.
804 inst_type :: { LHsType RdrName }
805 : sigtype {% checkInstType $1 }
807 inst_types1 :: { [LHsType RdrName] }
809 | inst_type ',' inst_types1 { $1 : $3 }
811 comma_types0 :: { [LHsType RdrName] }
812 : comma_types1 { $1 }
815 comma_types1 :: { [LHsType RdrName] }
817 | type ',' comma_types1 { $1 : $3 }
819 tv_bndrs :: { [LHsTyVarBndr RdrName] }
820 : tv_bndr tv_bndrs { $1 : $2 }
823 tv_bndr :: { LHsTyVarBndr RdrName }
824 : tyvar { L1 (UserTyVar (unLoc $1)) }
825 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
827 fds :: { Located [Located ([RdrName], [RdrName])] }
828 : {- empty -} { noLoc [] }
829 | '|' fds1 { LL (reverse (unLoc $2)) }
831 fds1 :: { Located [Located ([RdrName], [RdrName])] }
832 : fds1 ',' fd { LL ($3 : unLoc $1) }
835 fd :: { Located ([RdrName], [RdrName]) }
836 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
837 (reverse (unLoc $1), reverse (unLoc $3)) }
839 varids0 :: { Located [RdrName] }
840 : {- empty -} { noLoc [] }
841 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
843 -----------------------------------------------------------------------------
848 | akind '->' kind { mkArrowKind $1 $3 }
851 : '*' { liftedTypeKind }
852 | '(' kind ')' { $2 }
855 -----------------------------------------------------------------------------
856 -- Datatype declarations
858 newconstr :: { LConDecl RdrName }
859 : conid atype { LL $ ConDecl $1 [] (noLoc []) (PrefixCon [$2]) }
860 | conid '{' var '::' ctype '}'
861 { LL $ ConDecl $1 [] (noLoc []) (RecCon [($3, $5)]) }
863 gadt_constrlist :: { Located [LConDecl RdrName] }
864 : '{' gadt_constrs '}' { LL (unLoc $2) }
865 | vocurly gadt_constrs close { $2 }
867 gadt_constrs :: { Located [LConDecl RdrName] }
868 : gadt_constrs ';' gadt_constr { LL ($3 : unLoc $1) }
869 | gadt_constr { L1 [$1] }
871 gadt_constr :: { LConDecl RdrName }
873 { LL (GadtDecl $1 $3) }
875 constrs :: { Located [LConDecl RdrName] }
876 : {- empty; a GHC extension -} { noLoc [] }
877 | '=' constrs1 { LL (unLoc $2) }
879 constrs1 :: { Located [LConDecl RdrName] }
880 : constrs1 '|' constr { LL ($3 : unLoc $1) }
883 constr :: { LConDecl RdrName }
884 : forall context '=>' constr_stuff
885 { let (con,details) = unLoc $4 in
886 LL (ConDecl con (unLoc $1) $2 details) }
887 | forall constr_stuff
888 { let (con,details) = unLoc $2 in
889 LL (ConDecl con (unLoc $1) (noLoc []) details) }
891 forall :: { Located [LHsTyVarBndr RdrName] }
892 : 'forall' tv_bndrs '.' { LL $2 }
893 | {- empty -} { noLoc [] }
895 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
896 -- We parse the constructor declaration
898 -- as a btype (treating C as a type constructor) and then convert C to be
899 -- a data constructor. Reason: it might continue like this:
901 -- in which case C really would be a type constructor. We can't resolve this
902 -- ambiguity till we come across the constructor oprerator :% (or not, more usually)
903 : btype {% mkPrefixCon $1 [] >>= return.LL }
904 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
905 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
906 | btype conop btype { LL ($2, InfixCon $1 $3) }
908 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
909 : fielddecl ',' fielddecls { unLoc $1 : $3 }
910 | fielddecl { [unLoc $1] }
912 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
913 : sig_vars '::' ctype { LL (reverse (unLoc $1), $3) }
915 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
916 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
917 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
918 -- We don't allow a context, but that's sorted out by the type checker.
919 deriving :: { Located (Maybe [LHsType RdrName]) }
920 : {- empty -} { noLoc Nothing }
921 | 'deriving' qtycon {% do { let { L loc tv = $2 }
922 ; p <- checkInstType (L loc (HsTyVar tv))
923 ; return (LL (Just [p])) } }
924 | 'deriving' '(' ')' { LL (Just []) }
925 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
926 -- Glasgow extension: allow partial
927 -- applications in derivings
929 -----------------------------------------------------------------------------
932 {- There's an awkward overlap with a type signature. Consider
933 f :: Int -> Int = ...rhs...
934 Then we can't tell whether it's a type signature or a value
935 definition with a result signature until we see the '='.
936 So we have to inline enough to postpone reductions until we know.
940 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
941 instead of qvar, we get another shift/reduce-conflict. Consider the
944 { (^^) :: Int->Int ; } Type signature; only var allowed
946 { (^^) :: Int->Int = ... ; } Value defn with result signature;
947 qvar allowed (because of instance decls)
949 We can't tell whether to reduce var to qvar until after we've read the signatures.
952 decl :: { Located (OrdList (LHsDecl RdrName)) }
954 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 $3;
955 return (LL $ unitOL (LL $ ValD r)) } }
957 rhs :: { Located (GRHSs RdrName) }
958 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
959 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
961 gdrhs :: { Located [LGRHS RdrName] }
962 : gdrhs gdrh { LL ($2 : unLoc $1) }
965 gdrh :: { LGRHS RdrName }
966 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
969 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
970 : infixexp '::' sigtype
971 {% do s <- checkValSig $1 $3;
972 return (LL $ unitOL (LL $ SigD s)) }
973 -- See the above notes for why we need infixexp here
974 | var ',' sig_vars '::' sigtype
975 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
976 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
978 | '{-# INLINE' activation qvar '#-}'
979 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
980 | '{-# NOINLINE' inverse_activation qvar '#-}'
981 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
982 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
983 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
985 | '{-# SPECIALISE' 'instance' inst_type '#-}'
986 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
988 -----------------------------------------------------------------------------
991 exp :: { LHsExpr RdrName }
992 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
993 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
994 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
995 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
996 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
999 infixexp :: { LHsExpr RdrName }
1001 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
1003 exp10 :: { LHsExpr RdrName }
1004 : '\\' aexp aexps opt_asig '->' exp
1005 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
1006 return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
1007 (GRHSs (unguardedRHS $6) []
1009 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1010 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1011 | 'case' exp 'of' altslist { LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1012 | '-' fexp { LL $ mkHsNegApp $2 }
1014 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1015 checkDo loc (unLoc $2) >>= \ stmts ->
1016 return (L loc (mkHsDo DoExpr stmts)) }
1017 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1018 checkMDo loc (unLoc $2) >>= \ stmts ->
1019 return (L loc (mkHsDo MDoExpr stmts)) }
1021 | scc_annot exp { LL $ if opt_SccProfilingOn
1022 then HsSCC (unLoc $1) $2
1025 | 'proc' aexp '->' exp
1026 {% checkPattern $2 >>= \ p ->
1027 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1028 placeHolderType undefined)) }
1029 -- TODO: is LL right here?
1031 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1032 -- hdaume: core annotation
1035 scc_annot :: { Located FastString }
1036 : '_scc_' STRING { LL $ getSTRING $2 }
1037 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1039 fexp :: { LHsExpr RdrName }
1040 : fexp aexp { LL $ HsApp $1 $2 }
1043 aexps :: { [LHsExpr RdrName] }
1044 : aexps aexp { $2 : $1 }
1045 | {- empty -} { [] }
1047 aexp :: { LHsExpr RdrName }
1048 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1049 | '~' aexp { LL $ ELazyPat $2 }
1052 aexp1 :: { LHsExpr RdrName }
1053 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1058 -- Here was the syntax for type applications that I was planning
1059 -- but there are difficulties (e.g. what order for type args)
1060 -- so it's not enabled yet.
1061 -- But this case *is* used for the left hand side of a generic definition,
1062 -- which is parsed as an expression before being munged into a pattern
1063 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1064 (sL (getLoc $3) (HsType $3)) }
1066 aexp2 :: { LHsExpr RdrName }
1067 : ipvar { L1 (HsIPVar $! unLoc $1) }
1068 | qcname { L1 (HsVar $! unLoc $1) }
1069 | literal { L1 (HsLit $! unLoc $1) }
1070 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1071 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1072 | '(' exp ')' { LL (HsPar $2) }
1073 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1074 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1075 | '[' list ']' { LL (unLoc $2) }
1076 | '[:' parr ':]' { LL (unLoc $2) }
1077 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1078 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1079 | '_' { L1 EWildPat }
1081 -- MetaHaskell Extension
1082 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1083 (L1 $ HsVar (mkUnqual varName
1084 (getTH_ID_SPLICE $1)))) } -- $x
1085 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1087 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1088 | TH_VAR_QUOTE gcon { LL $ HsBracket (VarBr (unLoc $2)) }
1089 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1090 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1091 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1092 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1093 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1094 return (LL $ HsBracket (PatBr p)) }
1095 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1097 -- arrow notation extension
1098 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1100 cmdargs :: { [LHsCmdTop RdrName] }
1101 : cmdargs acmd { $2 : $1 }
1102 | {- empty -} { [] }
1104 acmd :: { LHsCmdTop RdrName }
1105 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1107 cvtopbody :: { [LHsDecl RdrName] }
1108 : '{' cvtopdecls0 '}' { $2 }
1109 | vocurly cvtopdecls0 close { $2 }
1111 cvtopdecls0 :: { [LHsDecl RdrName] }
1112 : {- empty -} { [] }
1115 texps :: { [LHsExpr RdrName] }
1116 : texps ',' exp { $3 : $1 }
1120 -----------------------------------------------------------------------------
1123 -- The rules below are little bit contorted to keep lexps left-recursive while
1124 -- avoiding another shift/reduce-conflict.
1126 list :: { LHsExpr RdrName }
1127 : exp { L1 $ ExplicitList placeHolderType [$1] }
1128 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1129 | exp '..' { LL $ ArithSeqIn (From $1) }
1130 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1131 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1132 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1133 | exp pquals { LL $ mkHsDo ListComp
1134 (reverse (L (getLoc $1) (ResultStmt $1) :
1137 lexps :: { Located [LHsExpr RdrName] }
1138 : lexps ',' exp { LL ($3 : unLoc $1) }
1139 | exp ',' exp { LL [$3,$1] }
1141 -----------------------------------------------------------------------------
1142 -- List Comprehensions
1144 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1145 -- or a reversed list of Stmts
1146 : pquals1 { case unLoc $1 of
1148 qss -> L1 [L1 (ParStmt stmtss)]
1150 stmtss = [ (reverse qs, undefined)
1154 pquals1 :: { Located [[LStmt RdrName]] }
1155 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1156 | '|' quals { L (getLoc $2) [unLoc $2] }
1158 quals :: { Located [LStmt RdrName] }
1159 : quals ',' qual { LL ($3 : unLoc $1) }
1162 -----------------------------------------------------------------------------
1163 -- Parallel array expressions
1165 -- The rules below are little bit contorted; see the list case for details.
1166 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1167 -- Moreover, we allow explicit arrays with no element (represented by the nil
1168 -- constructor in the list case).
1170 parr :: { LHsExpr RdrName }
1171 : { noLoc (ExplicitPArr placeHolderType []) }
1172 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1173 | lexps { L1 $ ExplicitPArr placeHolderType
1174 (reverse (unLoc $1)) }
1175 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1176 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1177 | exp pquals { LL $ mkHsDo PArrComp
1178 (reverse (L (getLoc $1) (ResultStmt $1) :
1182 -- We are reusing `lexps' and `pquals' from the list case.
1184 -----------------------------------------------------------------------------
1185 -- Case alternatives
1187 altslist :: { Located [LMatch RdrName] }
1188 : '{' alts '}' { LL (reverse (unLoc $2)) }
1189 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1191 alts :: { Located [LMatch RdrName] }
1192 : alts1 { L1 (unLoc $1) }
1193 | ';' alts { LL (unLoc $2) }
1195 alts1 :: { Located [LMatch RdrName] }
1196 : alts1 ';' alt { LL ($3 : unLoc $1) }
1197 | alts1 ';' { LL (unLoc $1) }
1200 alt :: { LMatch RdrName }
1201 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1202 return (LL (Match [p] $2 (unLoc $3))) }
1204 alt_rhs :: { Located (GRHSs RdrName) }
1205 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)) }
1207 ralt :: { Located [LGRHS RdrName] }
1208 : '->' exp { LL (unguardedRHS $2) }
1209 | gdpats { L1 (reverse (unLoc $1)) }
1211 gdpats :: { Located [LGRHS RdrName] }
1212 : gdpats gdpat { LL ($2 : unLoc $1) }
1215 gdpat :: { LGRHS RdrName }
1216 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1217 in LL $ GRHS (reverse (r : unLoc $2)) }
1219 -----------------------------------------------------------------------------
1220 -- Statement sequences
1222 stmtlist :: { Located [LStmt RdrName] }
1223 : '{' stmts '}' { LL (unLoc $2) }
1224 | vocurly stmts close { $2 }
1226 -- do { ;; s ; s ; ; s ;; }
1227 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1228 -- here, because we need too much lookahead if we see do { e ; }
1229 -- So we use ExprStmts throughout, and switch the last one over
1230 -- in ParseUtils.checkDo instead
1231 stmts :: { Located [LStmt RdrName] }
1232 : stmt stmts_help { LL ($1 : unLoc $2) }
1233 | ';' stmts { LL (unLoc $2) }
1234 | {- empty -} { noLoc [] }
1236 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1237 : ';' stmts { LL (unLoc $2) }
1238 | {- empty -} { noLoc [] }
1240 -- For typing stmts at the GHCi prompt, where
1241 -- the input may consist of just comments.
1242 maybe_stmt :: { Maybe (LStmt RdrName) }
1244 | {- nothing -} { Nothing }
1246 stmt :: { LStmt RdrName }
1248 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1249 return (LL $ BindStmt p $1) }
1250 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1252 qual :: { LStmt RdrName }
1253 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1254 return (LL $ BindStmt p $3) }
1255 | exp { L1 $ ExprStmt $1 placeHolderType }
1256 | 'let' binds { LL $ LetStmt (unLoc $2) }
1258 -----------------------------------------------------------------------------
1259 -- Record Field Update/Construction
1261 fbinds :: { HsRecordBinds RdrName }
1263 | {- empty -} { [] }
1265 fbinds1 :: { HsRecordBinds RdrName }
1266 : fbinds1 ',' fbind { $3 : $1 }
1269 fbind :: { (Located RdrName, LHsExpr RdrName) }
1270 : qvar '=' exp { ($1,$3) }
1272 -----------------------------------------------------------------------------
1273 -- Implicit Parameter Bindings
1275 dbinds :: { Located [LIPBind RdrName] }
1276 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1277 | dbinds ';' { LL (unLoc $1) }
1279 -- | {- empty -} { [] }
1281 dbind :: { LIPBind RdrName }
1282 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1284 -----------------------------------------------------------------------------
1285 -- Variables, Constructors and Operators.
1287 identifier :: { Located RdrName }
1293 depreclist :: { Located [RdrName] }
1294 depreclist : deprec_var { L1 [unLoc $1] }
1295 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1297 deprec_var :: { Located RdrName }
1298 deprec_var : var { $1 }
1301 gcon :: { Located RdrName } -- Data constructor namespace
1302 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1304 -- the case of '[:' ':]' is part of the production `parr'
1306 sysdcon :: { Located DataCon } -- Wired in data constructors
1307 : '(' ')' { LL unitDataCon }
1308 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1309 | '[' ']' { LL nilDataCon }
1311 var :: { Located RdrName }
1313 | '(' varsym ')' { LL (unLoc $2) }
1315 qvar :: { Located RdrName }
1317 | '(' varsym ')' { LL (unLoc $2) }
1318 | '(' qvarsym1 ')' { LL (unLoc $2) }
1319 -- We've inlined qvarsym here so that the decision about
1320 -- whether it's a qvar or a var can be postponed until
1321 -- *after* we see the close paren.
1323 ipvar :: { Located (IPName RdrName) }
1324 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1325 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1327 qcon :: { Located RdrName }
1329 | '(' qconsym ')' { LL (unLoc $2) }
1331 varop :: { Located RdrName }
1333 | '`' varid '`' { LL (unLoc $2) }
1335 qvarop :: { Located RdrName }
1337 | '`' qvarid '`' { LL (unLoc $2) }
1339 qvaropm :: { Located RdrName }
1340 : qvarsym_no_minus { $1 }
1341 | '`' qvarid '`' { LL (unLoc $2) }
1343 conop :: { Located RdrName }
1345 | '`' conid '`' { LL (unLoc $2) }
1347 qconop :: { Located RdrName }
1349 | '`' qconid '`' { LL (unLoc $2) }
1351 -----------------------------------------------------------------------------
1352 -- Type constructors
1354 gtycon :: { Located RdrName } -- A "general" qualified tycon
1356 | '(' ')' { LL $ getRdrName unitTyCon }
1357 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1358 | '(' '->' ')' { LL $ getRdrName funTyCon }
1359 | '[' ']' { LL $ listTyCon_RDR }
1360 | '[:' ':]' { LL $ parrTyCon_RDR }
1362 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1364 | '(' qtyconsym ')' { LL (unLoc $2) }
1366 qtyconop :: { Located RdrName } -- Qualified or unqualified
1368 | '`' qtycon '`' { LL (unLoc $2) }
1370 tyconop :: { Located RdrName } -- Unqualified
1372 | '`' tycon '`' { LL (unLoc $2) }
1374 qtycon :: { Located RdrName } -- Qualified or unqualified
1375 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1378 tycon :: { Located RdrName } -- Unqualified
1379 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1381 qtyconsym :: { Located RdrName }
1382 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1385 tyconsym :: { Located RdrName }
1386 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1388 -----------------------------------------------------------------------------
1391 op :: { Located RdrName } -- used in infix decls
1395 qop :: { LHsExpr RdrName } -- used in sections
1396 : qvarop { L1 $ HsVar (unLoc $1) }
1397 | qconop { L1 $ HsVar (unLoc $1) }
1399 qopm :: { LHsExpr RdrName } -- used in sections
1400 : qvaropm { L1 $ HsVar (unLoc $1) }
1401 | qconop { L1 $ HsVar (unLoc $1) }
1403 -----------------------------------------------------------------------------
1406 qvarid :: { Located RdrName }
1408 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1410 varid :: { Located RdrName }
1411 : varid_no_unsafe { $1 }
1412 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1413 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1414 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1416 varid_no_unsafe :: { Located RdrName }
1417 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1418 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1419 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1421 tyvar :: { Located RdrName }
1422 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1423 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1424 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1425 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1426 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1428 -- These special_ids are treated as keywords in various places,
1429 -- but as ordinary ids elsewhere. 'special_id' collects all these
1430 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1431 special_id :: { Located UserFS }
1433 : 'as' { L1 FSLIT("as") }
1434 | 'qualified' { L1 FSLIT("qualified") }
1435 | 'hiding' { L1 FSLIT("hiding") }
1436 | 'export' { L1 FSLIT("export") }
1437 | 'label' { L1 FSLIT("label") }
1438 | 'dynamic' { L1 FSLIT("dynamic") }
1439 | 'stdcall' { L1 FSLIT("stdcall") }
1440 | 'ccall' { L1 FSLIT("ccall") }
1442 -----------------------------------------------------------------------------
1445 qvarsym :: { Located RdrName }
1449 qvarsym_no_minus :: { Located RdrName }
1450 : varsym_no_minus { $1 }
1453 qvarsym1 :: { Located RdrName }
1454 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1456 varsym :: { Located RdrName }
1457 : varsym_no_minus { $1 }
1458 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1460 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1461 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1462 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1465 -- See comments with special_id
1466 special_sym :: { Located UserFS }
1467 special_sym : '!' { L1 FSLIT("!") }
1468 | '.' { L1 FSLIT(".") }
1469 | '*' { L1 FSLIT("*") }
1471 -----------------------------------------------------------------------------
1472 -- Data constructors
1474 qconid :: { Located RdrName } -- Qualified or unqualified
1476 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1478 conid :: { Located RdrName }
1479 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1481 qconsym :: { Located RdrName } -- Qualified or unqualified
1483 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1485 consym :: { Located RdrName }
1486 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1488 -- ':' means only list cons
1489 | ':' { L1 $ consDataCon_RDR }
1492 -----------------------------------------------------------------------------
1495 literal :: { Located HsLit }
1496 : CHAR { L1 $ HsChar $ getCHAR $1 }
1497 | STRING { L1 $ HsString $ getSTRING $1 }
1498 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1499 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1500 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1501 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1502 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1504 -----------------------------------------------------------------------------
1508 : vccurly { () } -- context popped in lexer.
1509 | error {% popContext }
1511 -----------------------------------------------------------------------------
1512 -- Miscellaneous (mostly renamings)
1514 modid :: { Located ModuleName }
1515 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1516 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1519 (unpackFS mod ++ '.':unpackFS c))
1523 : commas ',' { $1 + 1 }
1526 -----------------------------------------------------------------------------
1530 happyError = srcParseFail
1532 getVARID (L _ (ITvarid x)) = x
1533 getCONID (L _ (ITconid x)) = x
1534 getVARSYM (L _ (ITvarsym x)) = x
1535 getCONSYM (L _ (ITconsym x)) = x
1536 getQVARID (L _ (ITqvarid x)) = x
1537 getQCONID (L _ (ITqconid x)) = x
1538 getQVARSYM (L _ (ITqvarsym x)) = x
1539 getQCONSYM (L _ (ITqconsym x)) = x
1540 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1541 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1542 getCHAR (L _ (ITchar x)) = x
1543 getSTRING (L _ (ITstring x)) = x
1544 getINTEGER (L _ (ITinteger x)) = x
1545 getRATIONAL (L _ (ITrational x)) = x
1546 getPRIMCHAR (L _ (ITprimchar x)) = x
1547 getPRIMSTRING (L _ (ITprimstring x)) = x
1548 getPRIMINTEGER (L _ (ITprimint x)) = x
1549 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1550 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1551 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1553 -- Utilities for combining source spans
1554 comb2 :: Located a -> Located b -> SrcSpan
1557 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1558 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1560 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1561 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1562 combineSrcSpans (getLoc c) (getLoc d)
1564 -- strict constructor version:
1566 sL :: SrcSpan -> a -> Located a
1567 sL span a = span `seq` L span a
1569 -- Make a source location for the file. We're a bit lazy here and just
1570 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1571 -- try to find the span of the whole file (ToDo).
1572 fileSrcSpan :: P SrcSpan
1575 let loc = mkSrcLoc (srcLocFile l) 1 0;
1576 return (mkSrcSpan loc loc)