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 (unLoc $2) (reverse (unLoc $3)) Nothing) }
336 | 'newtype' tycl_hdr -- Constructor is optional
337 { TyClD (mkTyData NewType (unLoc $2) [] Nothing) }
338 | 'newtype' tycl_hdr '=' newconstr
339 { TyClD (mkTyData NewType (unLoc $2) [$4] Nothing) }
340 | 'class' tycl_hdr fds
341 { TyClD (mkClassDecl (unLoc $2) (unLoc $3) [] emptyBag) }
343 -----------------------------------------------------------------------------
346 maybeexports :: { Maybe [LIE RdrName] }
347 : '(' exportlist ')' { Just $2 }
348 | {- empty -} { Nothing }
350 exportlist :: { [LIE RdrName] }
351 : exportlist ',' export { $3 : $1 }
352 | exportlist ',' { $1 }
356 -- No longer allow things like [] and (,,,) to be exported
357 -- They are built in syntax, always available
358 export :: { LIE RdrName }
359 : qvar { L1 (IEVar (unLoc $1)) }
360 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
361 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
362 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
363 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
364 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
366 qcnames :: { [RdrName] }
367 : qcnames ',' qcname { unLoc $3 : $1 }
368 | qcname { [unLoc $1] }
370 qcname :: { Located RdrName } -- Variable or data constructor
374 -----------------------------------------------------------------------------
375 -- Import Declarations
377 -- import decls can be *empty*, or even just a string of semicolons
378 -- whereas topdecls must contain at least one topdecl.
380 importdecls :: { [LImportDecl RdrName] }
381 : importdecls ';' importdecl { $3 : $1 }
382 | importdecls ';' { $1 }
383 | importdecl { [ $1 ] }
386 importdecl :: { LImportDecl RdrName }
387 : 'import' maybe_src optqualified modid maybeas maybeimpspec
388 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
390 maybe_src :: { IsBootInterface }
391 : '{-# SOURCE' '#-}' { True }
392 | {- empty -} { False }
394 optqualified :: { Bool }
395 : 'qualified' { True }
396 | {- empty -} { False }
398 maybeas :: { Located (Maybe ModuleName) }
399 : 'as' modid { LL (Just (unLoc $2)) }
400 | {- empty -} { noLoc Nothing }
402 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
403 : impspec { L1 (Just (unLoc $1)) }
404 | {- empty -} { noLoc Nothing }
406 impspec :: { Located (Bool, [LIE RdrName]) }
407 : '(' exportlist ')' { LL (False, reverse $2) }
408 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
410 -----------------------------------------------------------------------------
411 -- Fixity Declarations
415 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
417 infix :: { Located FixityDirection }
418 : 'infix' { L1 InfixN }
419 | 'infixl' { L1 InfixL }
420 | 'infixr' { L1 InfixR }
422 ops :: { Located [Located RdrName] }
423 : ops ',' op { LL ($3 : unLoc $1) }
426 -----------------------------------------------------------------------------
427 -- Top-Level Declarations
429 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
430 : topdecls ';' topdecl { $1 `appOL` $3 }
431 | topdecls ';' { $1 }
434 topdecl :: { OrdList (LHsDecl RdrName) }
435 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
436 | 'instance' inst_type where
437 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
438 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
439 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
440 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
441 | '{-# DEPRECATED' deprecations '#-}' { $2 }
442 | '{-# RULES' rules '#-}' { $2 }
443 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
446 tycl_decl :: { LTyClDecl RdrName }
447 : 'type' syn_hdr '=' ctype
448 -- Note ctype, not sigtype.
449 -- We allow an explicit for-all but we don't insert one
450 -- in type Foo a = (b,b)
451 -- Instead we just say b is out of scope
452 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
454 | 'data' tycl_hdr constrs deriving
455 { L (comb4 $1 $2 $3 $4)
456 (mkTyData DataType (unLoc $2) (reverse (unLoc $3)) (unLoc $4)) }
458 | 'newtype' tycl_hdr '=' newconstr deriving
460 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
462 | 'class' tycl_hdr fds where
464 (binds,sigs) = cvBindsAndSigs (unLoc $4)
466 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
469 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
470 -- We don't retain the syntax of an infix
471 -- type synonym declaration. Oh well.
472 : tycon tv_bndrs { ($1, $2) }
473 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
475 -- tycl_hdr parses the header of a type or class decl,
476 -- which takes the form
479 -- (Eq a, Ord b) => T a b
480 -- Rather a lot of inlining here, else we get reduce/reduce errors
481 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
482 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
483 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
485 -----------------------------------------------------------------------------
486 -- Nested declarations
488 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
489 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
490 | decls ';' { LL (unLoc $1) }
492 | {- empty -} { noLoc nilOL }
495 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
496 : '{' decls '}' { LL (unLoc $2) }
497 | vocurly decls close { $2 }
499 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
500 -- No implicit parameters
501 : 'where' decllist { LL (unLoc $2) }
502 | {- empty -} { noLoc nilOL }
504 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
505 : decllist { L1 [cvBindGroup (unLoc $1)] }
506 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
507 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
509 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
510 : 'where' binds { LL (unLoc $2) }
511 | {- empty -} { noLoc [] }
514 -----------------------------------------------------------------------------
515 -- Transformation Rules
517 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
518 : rules ';' rule { $1 `snocOL` $3 }
521 | {- empty -} { nilOL }
523 rule :: { LHsDecl RdrName }
524 : STRING activation rule_forall infixexp '=' exp
525 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
527 activation :: { Activation } -- Omitted means AlwaysActive
528 : {- empty -} { AlwaysActive }
529 | explicit_activation { $1 }
531 inverse_activation :: { Activation } -- Omitted means NeverActive
532 : {- empty -} { NeverActive }
533 | explicit_activation { $1 }
535 explicit_activation :: { Activation } -- In brackets
536 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
537 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
539 rule_forall :: { [RuleBndr RdrName] }
540 : 'forall' rule_var_list '.' { $2 }
543 rule_var_list :: { [RuleBndr RdrName] }
545 | rule_var rule_var_list { $1 : $2 }
547 rule_var :: { RuleBndr RdrName }
548 : varid { RuleBndr $1 }
549 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
551 -----------------------------------------------------------------------------
552 -- Deprecations (c.f. rules)
554 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
555 : deprecations ';' deprecation { $1 `appOL` $3 }
556 | deprecations ';' { $1 }
558 | {- empty -} { nilOL }
560 -- SUP: TEMPORARY HACK, not checking for `module Foo'
561 deprecation :: { OrdList (LHsDecl RdrName) }
563 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
567 -----------------------------------------------------------------------------
568 -- Foreign import and export declarations
570 -- for the time being, the following accepts foreign declarations conforming
571 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
573 -- * a flag indicates whether pre-standard declarations have been used and
574 -- triggers a deprecation warning further down the road
576 -- NB: The first two rules could be combined into one by replacing `safety1'
577 -- with `safety'. However, the combined rule conflicts with the
580 fdecl :: { LHsDecl RdrName }
581 fdecl : 'import' callconv safety1 fspec
582 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
583 | 'import' callconv fspec
584 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
586 | 'export' callconv fspec
587 {% mkExport $2 (unLoc $3) >>= return.LL }
588 -- the following syntax is DEPRECATED
589 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
590 | fdecl2DEPRECATED { L1 (unLoc $1) }
592 fdecl1DEPRECATED :: { LForeignDecl RdrName }
594 ----------- DEPRECATED label decls ------------
595 : 'label' ext_name varid '::' sigtype
596 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
597 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
599 ----------- DEPRECATED ccall/stdcall decls ------------
601 -- NB: This business with the case expression below may seem overly
602 -- complicated, but it is necessary to avoid some conflicts.
604 -- DEPRECATED variant #1: lack of a calling convention specification
606 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
608 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
610 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
611 (CFunction target)) True }
613 -- DEPRECATED variant #2: external name consists of two separate strings
614 -- (module name and function name) (import)
615 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
617 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
618 CCall cconv -> return $
620 imp = CFunction (StaticTarget (getSTRING $4))
622 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
624 -- DEPRECATED variant #3: `unsafe' after entity
625 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
627 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
628 CCall cconv -> return $
630 imp = CFunction (StaticTarget (getSTRING $3))
632 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
634 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
635 -- an explicit calling convention (import)
636 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
637 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
638 (CFunction DynamicTarget)) True }
640 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
641 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
643 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
644 CCall cconv -> return $
645 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
646 (CFunction DynamicTarget)) True }
648 -- DEPRECATED variant #6: lack of a calling convention specification
650 | 'export' {-no callconv-} ext_name varid '::' sigtype
651 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
652 defaultCCallConv)) True }
654 -- DEPRECATED variant #7: external name consists of two separate strings
655 -- (module name and function name) (export)
656 | 'export' callconv STRING STRING varid '::' sigtype
658 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
659 CCall cconv -> return $
660 LL $ ForeignExport $5 $7
661 (CExport (CExportStatic (getSTRING $4) cconv)) True }
663 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
664 -- an explicit calling convention (export)
665 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
666 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
669 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
670 | 'export' callconv 'dynamic' varid '::' sigtype
672 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
673 CCall cconv -> return $
674 LL $ ForeignImport $4 $6
675 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
677 ----------- DEPRECATED .NET decls ------------
678 -- NB: removed the .NET call declaration, as it is entirely subsumed
679 -- by the new standard FFI declarations
681 fdecl2DEPRECATED :: { LHsDecl RdrName }
683 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
684 -- left this one unchanged for the moment as type imports are not
685 -- covered currently by the FFI standard -=chak
688 callconv :: { CallConv }
689 : 'stdcall' { CCall StdCallConv }
690 | 'ccall' { CCall CCallConv }
691 | 'dotnet' { DNCall }
694 : 'unsafe' { PlayRisky }
695 | 'safe' { PlaySafe False }
696 | 'threadsafe' { PlaySafe True }
697 | {- empty -} { PlaySafe False }
699 safety1 :: { Safety }
700 : 'unsafe' { PlayRisky }
701 | 'safe' { PlaySafe False }
702 | 'threadsafe' { PlaySafe True }
703 -- only needed to avoid conflicts with the DEPRECATED rules
705 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
706 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
707 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
708 -- if the entity string is missing, it defaults to the empty string;
709 -- the meaning of an empty entity string depends on the calling
713 ext_name :: { Maybe CLabelString }
714 : STRING { Just (getSTRING $1) }
715 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
716 | {- empty -} { Nothing }
719 -----------------------------------------------------------------------------
722 opt_sig :: { Maybe (LHsType RdrName) }
723 : {- empty -} { Nothing }
724 | '::' sigtype { Just $2 }
726 opt_asig :: { Maybe (LHsType RdrName) }
727 : {- empty -} { Nothing }
728 | '::' atype { Just $2 }
730 sigtypes1 :: { [LHsType RdrName] }
732 | sigtype ',' sigtypes1 { $1 : $3 }
734 sigtype :: { LHsType RdrName }
735 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
736 -- Wrap an Implicit forall if there isn't one there already
738 sig_vars :: { Located [Located RdrName] }
739 : sig_vars ',' var { LL ($3 : unLoc $1) }
742 -----------------------------------------------------------------------------
745 -- A ctype is a for-all type
746 ctype :: { LHsType RdrName }
747 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
748 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
749 -- A type of form (context => type) is an *implicit* HsForAllTy
752 -- We parse a context as a btype so that we don't get reduce/reduce
753 -- errors in ctype. The basic problem is that
755 -- looks so much like a tuple type. We can't tell until we find the =>
756 context :: { LHsContext RdrName }
757 : btype {% checkContext $1 }
759 type :: { LHsType RdrName }
760 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
763 gentype :: { LHsType RdrName }
765 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
766 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
767 | btype '->' gentype { LL $ HsFunTy $1 $3 }
769 btype :: { LHsType RdrName }
770 : btype atype { LL $ HsAppTy $1 $2 }
773 atype :: { LHsType RdrName }
774 : gtycon { L1 (HsTyVar (unLoc $1)) }
775 | tyvar { L1 (HsTyVar (unLoc $1)) }
776 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
777 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
778 | '[' type ']' { LL $ HsListTy $2 }
779 | '[:' type ':]' { LL $ HsPArrTy $2 }
780 | '(' ctype ')' { LL $ HsParTy $2 }
781 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
783 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
785 -- An inst_type is what occurs in the head of an instance decl
786 -- e.g. (Foo a, Gaz b) => Wibble a b
787 -- It's kept as a single type, with a MonoDictTy at the right
788 -- hand corner, for convenience.
789 inst_type :: { LHsType RdrName }
790 : ctype {% checkInstType $1 }
792 inst_types1 :: { [LHsType RdrName] }
794 | inst_type ',' inst_types1 { $1 : $3 }
796 comma_types0 :: { [LHsType RdrName] }
797 : comma_types1 { $1 }
800 comma_types1 :: { [LHsType RdrName] }
802 | type ',' comma_types1 { $1 : $3 }
804 tv_bndrs :: { [LHsTyVarBndr RdrName] }
805 : tv_bndr tv_bndrs { $1 : $2 }
808 tv_bndr :: { LHsTyVarBndr RdrName }
809 : tyvar { L1 (UserTyVar (unLoc $1)) }
810 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
812 fds :: { Located [Located ([RdrName], [RdrName])] }
813 : {- empty -} { noLoc [] }
814 | '|' fds1 { LL (reverse (unLoc $2)) }
816 fds1 :: { Located [Located ([RdrName], [RdrName])] }
817 : fds1 ',' fd { LL ($3 : unLoc $1) }
820 fd :: { Located ([RdrName], [RdrName]) }
821 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
822 (reverse (unLoc $1), reverse (unLoc $3)) }
824 varids0 :: { Located [RdrName] }
825 : {- empty -} { noLoc [] }
826 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
828 -----------------------------------------------------------------------------
833 | akind '->' kind { mkArrowKind $1 $3 }
836 : '*' { liftedTypeKind }
837 | '(' kind ')' { $2 }
840 -----------------------------------------------------------------------------
841 -- Datatype declarations
843 newconstr :: { LConDecl RdrName }
844 : conid atype { LL $ ConDecl $1 [] (noLoc [])
845 (PrefixCon [(unbangedType $2)]) }
846 | conid '{' var '::' ctype '}'
847 { LL $ ConDecl $1 [] (noLoc [])
848 (RecCon [($3, (unbangedType $5))]) }
850 constrs :: { Located [LConDecl RdrName] }
851 : {- empty; a GHC extension -} { noLoc [] }
852 | '=' constrs1 { LL (unLoc $2) }
854 constrs1 :: { Located [LConDecl RdrName] }
855 : constrs1 '|' constr { LL ($3 : unLoc $1) }
858 constr :: { LConDecl RdrName }
859 : forall context '=>' constr_stuff
860 { let (con,details) = unLoc $4 in
861 LL (ConDecl con (unLoc $1) $2 details) }
862 | forall constr_stuff
863 { let (con,details) = unLoc $2 in
864 LL (ConDecl con (unLoc $1) (noLoc []) details) }
866 forall :: { Located [LHsTyVarBndr RdrName] }
867 : 'forall' tv_bndrs '.' { LL $2 }
868 | {- empty -} { noLoc [] }
870 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
871 : btype {% mkPrefixCon $1 [] >>= return.LL }
872 | btype bang_atype satypes {% do { r <- mkPrefixCon $1 ($2 : unLoc $3);
873 return (L (comb3 $1 $2 $3) r) } }
874 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
875 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
876 | sbtype conop sbtype { LL ($2, InfixCon $1 $3) }
878 bang_atype :: { LBangType RdrName }
879 : strict_mark atype { LL (BangType (unLoc $1) $2) }
881 satypes :: { Located [LBangType RdrName] }
882 : atype satypes { LL (unbangedType $1 : unLoc $2) }
883 | bang_atype satypes { LL ($1 : unLoc $2) }
884 | {- empty -} { noLoc [] }
886 sbtype :: { LBangType RdrName }
887 : btype { unbangedType $1 }
888 | strict_mark atype { LL (BangType (unLoc $1) $2) }
890 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
891 : fielddecl ',' fielddecls { unLoc $1 : $3 }
892 | fielddecl { [unLoc $1] }
894 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
895 : sig_vars '::' stype { LL (reverse (unLoc $1), $3) }
897 stype :: { LBangType RdrName }
898 : ctype { unbangedType $1 }
899 | strict_mark atype { LL (BangType (unLoc $1) $2) }
901 strict_mark :: { Located HsBang }
902 : '!' { L1 HsStrict }
903 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
905 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
906 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
907 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
908 -- We don't allow a context, but that's sorted out by the type checker.
909 deriving :: { Located (Maybe [LHsType RdrName]) }
910 : {- empty -} { noLoc Nothing }
911 | 'deriving' qtycon {% do { let { L loc tv = $2 }
912 ; p <- checkInstType (L loc (HsTyVar tv))
913 ; return (LL (Just [p])) } }
914 | 'deriving' '(' ')' { LL (Just []) }
915 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
916 -- Glasgow extension: allow partial
917 -- applications in derivings
919 -----------------------------------------------------------------------------
922 {- There's an awkward overlap with a type signature. Consider
923 f :: Int -> Int = ...rhs...
924 Then we can't tell whether it's a type signature or a value
925 definition with a result signature until we see the '='.
926 So we have to inline enough to postpone reductions until we know.
930 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
931 instead of qvar, we get another shift/reduce-conflict. Consider the
934 { (^^) :: Int->Int ; } Type signature; only var allowed
936 { (^^) :: Int->Int = ... ; } Value defn with result signature;
937 qvar allowed (because of instance decls)
939 We can't tell whether to reduce var to qvar until after we've read the signatures.
942 decl :: { Located (OrdList (LHsDecl RdrName)) }
944 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 (unLoc $3);
945 return (LL $ unitOL (LL $ ValD r)) } }
947 rhs :: { Located (GRHSs RdrName) }
948 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) placeHolderType }
949 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) placeHolderType }
951 gdrhs :: { Located [LGRHS RdrName] }
952 : gdrhs gdrh { LL ($2 : unLoc $1) }
955 gdrh :: { LGRHS RdrName }
956 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
959 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
960 : infixexp '::' sigtype
961 {% do s <- checkValSig $1 $3;
962 return (LL $ unitOL (LL $ SigD s)) }
963 -- See the above notes for why we need infixexp here
964 | var ',' sig_vars '::' sigtype
965 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
966 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
968 | '{-# INLINE' activation qvar '#-}'
969 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
970 | '{-# NOINLINE' inverse_activation qvar '#-}'
971 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
972 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
973 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
975 | '{-# SPECIALISE' 'instance' inst_type '#-}'
976 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
978 -----------------------------------------------------------------------------
981 exp :: { LHsExpr RdrName }
982 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
983 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
984 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
985 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
986 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
989 infixexp :: { LHsExpr RdrName }
991 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
993 exp10 :: { LHsExpr RdrName }
994 : '\\' aexp aexps opt_asig '->' exp
995 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
996 return (LL $ HsLam (LL $ Match ps $4
997 (GRHSs (unguardedRHS $6) []
999 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1000 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1001 | 'case' exp 'of' altslist { LL $ HsCase $2 (unLoc $4) }
1002 | '-' fexp { LL $ mkHsNegApp $2 }
1004 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1005 checkDo loc (unLoc $2) >>= \ stmts ->
1006 return (L loc (mkHsDo DoExpr stmts)) }
1007 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1008 checkMDo loc (unLoc $2) >>= \ stmts ->
1009 return (L loc (mkHsDo MDoExpr stmts)) }
1011 | scc_annot exp { LL $ if opt_SccProfilingOn
1012 then HsSCC (unLoc $1) $2
1015 | 'proc' aexp '->' exp
1016 {% checkPattern $2 >>= \ p ->
1017 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1018 placeHolderType undefined)) }
1019 -- TODO: is LL right here?
1021 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1022 -- hdaume: core annotation
1025 scc_annot :: { Located FastString }
1026 : '_scc_' STRING { LL $ getSTRING $2 }
1027 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1029 fexp :: { LHsExpr RdrName }
1030 : fexp aexp { LL $ HsApp $1 $2 }
1033 aexps :: { [LHsExpr RdrName] }
1034 : aexps aexp { $2 : $1 }
1035 | {- empty -} { [] }
1037 aexp :: { LHsExpr RdrName }
1038 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1039 | '~' aexp { LL $ ELazyPat $2 }
1042 aexp1 :: { LHsExpr RdrName }
1043 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1048 -- Here was the syntax for type applications that I was planning
1049 -- but there are difficulties (e.g. what order for type args)
1050 -- so it's not enabled yet.
1051 -- But this case *is* used for the left hand side of a generic definition,
1052 -- which is parsed as an expression before being munged into a pattern
1053 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1054 (sL (getLoc $3) (HsType $3)) }
1056 aexp2 :: { LHsExpr RdrName }
1057 : ipvar { L1 (HsIPVar $! unLoc $1) }
1058 | qcname { L1 (HsVar $! unLoc $1) }
1059 | literal { L1 (HsLit $! unLoc $1) }
1060 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1061 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1062 | '(' exp ')' { LL (HsPar $2) }
1063 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1064 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1065 | '[' list ']' { LL (unLoc $2) }
1066 | '[:' parr ':]' { LL (unLoc $2) }
1067 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1068 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1069 | '_' { L1 EWildPat }
1071 -- MetaHaskell Extension
1072 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1073 (L1 $ HsVar (mkUnqual varName
1074 (getTH_ID_SPLICE $1)))) } -- $x
1075 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1077 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1078 | TH_VAR_QUOTE gcon { LL $ HsBracket (VarBr (unLoc $2)) }
1079 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1080 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1081 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1082 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1083 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1084 return (LL $ HsBracket (PatBr p)) }
1085 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1087 -- arrow notation extension
1088 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1090 cmdargs :: { [LHsCmdTop RdrName] }
1091 : cmdargs acmd { $2 : $1 }
1092 | {- empty -} { [] }
1094 acmd :: { LHsCmdTop RdrName }
1095 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1097 cvtopbody :: { [LHsDecl RdrName] }
1098 : '{' cvtopdecls0 '}' { $2 }
1099 | vocurly cvtopdecls0 close { $2 }
1101 cvtopdecls0 :: { [LHsDecl RdrName] }
1102 : {- empty -} { [] }
1105 texps :: { [LHsExpr RdrName] }
1106 : texps ',' exp { $3 : $1 }
1110 -----------------------------------------------------------------------------
1113 -- The rules below are little bit contorted to keep lexps left-recursive while
1114 -- avoiding another shift/reduce-conflict.
1116 list :: { LHsExpr RdrName }
1117 : exp { L1 $ ExplicitList placeHolderType [$1] }
1118 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1119 | exp '..' { LL $ ArithSeqIn (From $1) }
1120 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1121 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1122 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1123 | exp pquals { LL $ mkHsDo ListComp
1124 (reverse (L (getLoc $1) (ResultStmt $1) :
1127 lexps :: { Located [LHsExpr RdrName] }
1128 : lexps ',' exp { LL ($3 : unLoc $1) }
1129 | exp ',' exp { LL [$3,$1] }
1131 -----------------------------------------------------------------------------
1132 -- List Comprehensions
1134 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1135 -- or a reversed list of Stmts
1136 : pquals1 { case unLoc $1 of
1138 qss -> L1 [L1 (ParStmt stmtss)]
1140 stmtss = [ (reverse qs, undefined)
1144 pquals1 :: { Located [[LStmt RdrName]] }
1145 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1146 | '|' quals { L (getLoc $2) [unLoc $2] }
1148 quals :: { Located [LStmt RdrName] }
1149 : quals ',' qual { LL ($3 : unLoc $1) }
1152 -----------------------------------------------------------------------------
1153 -- Parallel array expressions
1155 -- The rules below are little bit contorted; see the list case for details.
1156 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1157 -- Moreover, we allow explicit arrays with no element (represented by the nil
1158 -- constructor in the list case).
1160 parr :: { LHsExpr RdrName }
1161 : { noLoc (ExplicitPArr placeHolderType []) }
1162 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1163 | lexps { L1 $ ExplicitPArr placeHolderType
1164 (reverse (unLoc $1)) }
1165 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1166 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1167 | exp pquals { LL $ mkHsDo PArrComp
1168 (reverse (L (getLoc $1) (ResultStmt $1) :
1172 -- We are reusing `lexps' and `pquals' from the list case.
1174 -----------------------------------------------------------------------------
1175 -- Case alternatives
1177 altslist :: { Located [LMatch RdrName] }
1178 : '{' alts '}' { LL (reverse (unLoc $2)) }
1179 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1181 alts :: { Located [LMatch RdrName] }
1182 : alts1 { L1 (unLoc $1) }
1183 | ';' alts { LL (unLoc $2) }
1185 alts1 :: { Located [LMatch RdrName] }
1186 : alts1 ';' alt { LL ($3 : unLoc $1) }
1187 | alts1 ';' { LL (unLoc $1) }
1190 alt :: { LMatch RdrName }
1191 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1192 return (LL (Match [p] $2 (unLoc $3))) }
1194 alt_rhs :: { Located (GRHSs RdrName) }
1195 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)
1198 ralt :: { Located [LGRHS RdrName] }
1199 : '->' exp { LL (unguardedRHS $2) }
1200 | gdpats { L1 (reverse (unLoc $1)) }
1202 gdpats :: { Located [LGRHS RdrName] }
1203 : gdpats gdpat { LL ($2 : unLoc $1) }
1206 gdpat :: { LGRHS RdrName }
1207 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1208 in LL $ GRHS (reverse (r : unLoc $2)) }
1210 -----------------------------------------------------------------------------
1211 -- Statement sequences
1213 stmtlist :: { Located [LStmt RdrName] }
1214 : '{' stmts '}' { LL (unLoc $2) }
1215 | vocurly stmts close { $2 }
1217 -- do { ;; s ; s ; ; s ;; }
1218 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1219 -- here, because we need too much lookahead if we see do { e ; }
1220 -- So we use ExprStmts throughout, and switch the last one over
1221 -- in ParseUtils.checkDo instead
1222 stmts :: { Located [LStmt RdrName] }
1223 : stmt stmts_help { LL ($1 : unLoc $2) }
1224 | ';' stmts { LL (unLoc $2) }
1225 | {- empty -} { noLoc [] }
1227 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1228 : ';' stmts { LL (unLoc $2) }
1229 | {- empty -} { noLoc [] }
1231 -- For typing stmts at the GHCi prompt, where
1232 -- the input may consist of just comments.
1233 maybe_stmt :: { Maybe (LStmt RdrName) }
1235 | {- nothing -} { Nothing }
1237 stmt :: { LStmt RdrName }
1239 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1240 return (LL $ BindStmt p $1) }
1241 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1243 qual :: { LStmt RdrName }
1244 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1245 return (LL $ BindStmt p $3) }
1246 | exp { L1 $ ExprStmt $1 placeHolderType }
1247 | 'let' binds { LL $ LetStmt (unLoc $2) }
1249 -----------------------------------------------------------------------------
1250 -- Record Field Update/Construction
1252 fbinds :: { HsRecordBinds RdrName }
1254 | {- empty -} { [] }
1256 fbinds1 :: { HsRecordBinds RdrName }
1257 : fbinds1 ',' fbind { $3 : $1 }
1260 fbind :: { (Located RdrName, LHsExpr RdrName) }
1261 : qvar '=' exp { ($1,$3) }
1263 -----------------------------------------------------------------------------
1264 -- Implicit Parameter Bindings
1266 dbinds :: { Located [LIPBind RdrName] }
1267 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1268 | dbinds ';' { LL (unLoc $1) }
1270 -- | {- empty -} { [] }
1272 dbind :: { LIPBind RdrName }
1273 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1275 -----------------------------------------------------------------------------
1276 -- Variables, Constructors and Operators.
1278 identifier :: { Located RdrName }
1284 depreclist :: { Located [RdrName] }
1285 depreclist : deprec_var { L1 [unLoc $1] }
1286 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1288 deprec_var :: { Located RdrName }
1289 deprec_var : var { $1 }
1292 gcon :: { Located RdrName } -- Data constructor namespace
1293 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1295 -- the case of '[:' ':]' is part of the production `parr'
1297 sysdcon :: { Located DataCon } -- Wired in data constructors
1298 : '(' ')' { LL unitDataCon }
1299 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1300 | '[' ']' { LL nilDataCon }
1302 var :: { Located RdrName }
1304 | '(' varsym ')' { LL (unLoc $2) }
1306 qvar :: { Located RdrName }
1308 | '(' varsym ')' { LL (unLoc $2) }
1309 | '(' qvarsym1 ')' { LL (unLoc $2) }
1310 -- We've inlined qvarsym here so that the decision about
1311 -- whether it's a qvar or a var can be postponed until
1312 -- *after* we see the close paren.
1314 ipvar :: { Located (IPName RdrName) }
1315 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1316 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1318 qcon :: { Located RdrName }
1320 | '(' qconsym ')' { LL (unLoc $2) }
1322 varop :: { Located RdrName }
1324 | '`' varid '`' { LL (unLoc $2) }
1326 qvarop :: { Located RdrName }
1328 | '`' qvarid '`' { LL (unLoc $2) }
1330 qvaropm :: { Located RdrName }
1331 : qvarsym_no_minus { $1 }
1332 | '`' qvarid '`' { LL (unLoc $2) }
1334 conop :: { Located RdrName }
1336 | '`' conid '`' { LL (unLoc $2) }
1338 qconop :: { Located RdrName }
1340 | '`' qconid '`' { LL (unLoc $2) }
1342 -----------------------------------------------------------------------------
1343 -- Type constructors
1345 gtycon :: { Located RdrName } -- A "general" qualified tycon
1347 | '(' ')' { LL $ getRdrName unitTyCon }
1348 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1349 | '(' '->' ')' { LL $ getRdrName funTyCon }
1350 | '[' ']' { LL $ listTyCon_RDR }
1351 | '[:' ':]' { LL $ parrTyCon_RDR }
1353 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1355 | '(' qtyconsym ')' { LL (unLoc $2) }
1357 qtyconop :: { Located RdrName } -- Qualified or unqualified
1359 | '`' qtycon '`' { LL (unLoc $2) }
1361 tyconop :: { Located RdrName } -- Unqualified
1363 | '`' tycon '`' { LL (unLoc $2) }
1365 qtycon :: { Located RdrName } -- Qualified or unqualified
1366 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1369 tycon :: { Located RdrName } -- Unqualified
1370 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1372 qtyconsym :: { Located RdrName }
1373 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1376 tyconsym :: { Located RdrName }
1377 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1379 -----------------------------------------------------------------------------
1382 op :: { Located RdrName } -- used in infix decls
1386 qop :: { LHsExpr RdrName } -- used in sections
1387 : qvarop { L1 $ HsVar (unLoc $1) }
1388 | qconop { L1 $ HsVar (unLoc $1) }
1390 qopm :: { LHsExpr RdrName } -- used in sections
1391 : qvaropm { L1 $ HsVar (unLoc $1) }
1392 | qconop { L1 $ HsVar (unLoc $1) }
1394 -----------------------------------------------------------------------------
1397 qvarid :: { Located RdrName }
1399 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1401 varid :: { Located RdrName }
1402 : varid_no_unsafe { $1 }
1403 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1404 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1405 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1407 varid_no_unsafe :: { Located RdrName }
1408 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1409 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1410 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1412 tyvar :: { Located RdrName }
1413 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1414 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1415 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1416 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1417 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1419 -- These special_ids are treated as keywords in various places,
1420 -- but as ordinary ids elsewhere. 'special_id' collects all these
1421 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1422 special_id :: { Located UserFS }
1424 : 'as' { L1 FSLIT("as") }
1425 | 'qualified' { L1 FSLIT("qualified") }
1426 | 'hiding' { L1 FSLIT("hiding") }
1427 | 'export' { L1 FSLIT("export") }
1428 | 'label' { L1 FSLIT("label") }
1429 | 'dynamic' { L1 FSLIT("dynamic") }
1430 | 'stdcall' { L1 FSLIT("stdcall") }
1431 | 'ccall' { L1 FSLIT("ccall") }
1433 -----------------------------------------------------------------------------
1436 qvarsym :: { Located RdrName }
1440 qvarsym_no_minus :: { Located RdrName }
1441 : varsym_no_minus { $1 }
1444 qvarsym1 :: { Located RdrName }
1445 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1447 varsym :: { Located RdrName }
1448 : varsym_no_minus { $1 }
1449 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1451 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1452 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1453 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1456 -- See comments with special_id
1457 special_sym :: { Located UserFS }
1458 special_sym : '!' { L1 FSLIT("!") }
1459 | '.' { L1 FSLIT(".") }
1460 | '*' { L1 FSLIT("*") }
1462 -----------------------------------------------------------------------------
1463 -- Data constructors
1465 qconid :: { Located RdrName } -- Qualified or unqualifiedb
1467 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1469 conid :: { Located RdrName }
1470 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1472 qconsym :: { Located RdrName } -- Qualified or unqualified
1474 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1476 consym :: { Located RdrName }
1477 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1479 -- ':' means only list cons
1480 | ':' { L1 $ consDataCon_RDR }
1483 -----------------------------------------------------------------------------
1486 literal :: { Located HsLit }
1487 : CHAR { L1 $ HsChar $ getCHAR $1 }
1488 | STRING { L1 $ HsString $ getSTRING $1 }
1489 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1490 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1491 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1492 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1493 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1495 -----------------------------------------------------------------------------
1499 : vccurly { () } -- context popped in lexer.
1500 | error {% popContext }
1502 -----------------------------------------------------------------------------
1503 -- Miscellaneous (mostly renamings)
1505 modid :: { Located ModuleName }
1506 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1507 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1510 (unpackFS mod ++ '.':unpackFS c))
1514 : commas ',' { $1 + 1 }
1517 -----------------------------------------------------------------------------
1521 happyError = srcParseFail
1523 getVARID (L _ (ITvarid x)) = x
1524 getCONID (L _ (ITconid x)) = x
1525 getVARSYM (L _ (ITvarsym x)) = x
1526 getCONSYM (L _ (ITconsym x)) = x
1527 getQVARID (L _ (ITqvarid x)) = x
1528 getQCONID (L _ (ITqconid x)) = x
1529 getQVARSYM (L _ (ITqvarsym x)) = x
1530 getQCONSYM (L _ (ITqconsym x)) = x
1531 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1532 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1533 getCHAR (L _ (ITchar x)) = x
1534 getSTRING (L _ (ITstring x)) = x
1535 getINTEGER (L _ (ITinteger x)) = x
1536 getRATIONAL (L _ (ITrational x)) = x
1537 getPRIMCHAR (L _ (ITprimchar x)) = x
1538 getPRIMSTRING (L _ (ITprimstring x)) = x
1539 getPRIMINTEGER (L _ (ITprimint x)) = x
1540 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1541 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1542 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1544 -- Utilities for combining source spans
1545 comb2 :: Located a -> Located b -> SrcSpan
1548 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1549 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1551 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1552 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1553 combineSrcSpans (getLoc c) (getLoc d)
1555 -- strict constructor version:
1557 sL :: SrcSpan -> a -> Located a
1558 sL span a = span `seq` L span a
1560 -- Make a source location for the file. We're a bit lazy here and just
1561 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1562 -- try to find the span of the whole file (ToDo).
1563 fileSrcSpan :: P SrcSpan
1566 let loc = mkSrcLoc (srcLocFile l) 1 0;
1567 return (mkSrcSpan loc loc)