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(..),
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 )
41 import CStrings ( CLabelString )
43 import Maybes ( orElse )
49 -----------------------------------------------------------------------------
50 Conflicts: 29 shift/reduce, [SDM 19/9/2002]
52 10 for abiguity in 'if x then y else z + 1' [State 136]
53 (shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
54 10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM
56 1 for ambiguity in 'if x then y else z with ?x=3' [State 136]
57 (shift parses as 'if x then y else (z with ?x=3)'
59 1 for ambiguity in 'if x then y else z :: T' [State 136]
60 (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
62 4 for ambiguity in 'if x then y else z -< e'
63 (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
65 8 for ambiguity in 'e :: a `b` c'. Does this mean [States 160,246]
69 1 for ambiguity in 'let ?x ...' [State 268]
70 the parser can't tell whether the ?x is the lhs of a normal binding or
71 an implicit binding. Fortunately resolving as shift gives it the only
72 sensible meaning, namely the lhs of an implicit binding.
74 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 332]
75 we don't know whether the '[' starts the activation or not: it
76 might be the start of the declaration with the activation being
79 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 394]
80 since 'forall' is a valid variable name, we don't know whether
81 to treat a forall on the input as the beginning of a quantifier
82 or the beginning of the rule itself. Resolving to shift means
83 it's always treated as a quantifier, hence the above is disallowed.
84 This saves explicitly defining a grammar for the rule lhs that
85 doesn't include 'forall'.
87 6 for conflicts between `fdecl' and `fdeclDEPRECATED', [States 384,385]
88 which are resolved correctly, and moreover,
89 should go away when `fdeclDEPRECATED' is removed.
91 -- ---------------------------------------------------------------------------
92 -- Adding location info
94 This is done in a stylised way using the three macros below, L0, L1
95 and LL. Each of these macros can be thought of as having type
97 L0, L1, LL :: a -> Located a
99 They each add a SrcSpan to their argument.
101 L0 adds 'noSrcSpan', used for empty productions
103 L1 for a production with a single token on the lhs. Grabs the SrcSpan
106 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
107 the first and last tokens.
109 These suffice for the majority of cases. However, we must be
110 especially careful with empty productions: LL won't work if the first
111 or last token on the lhs can represent an empty span. In these cases,
112 we have to calculate the span using more of the tokens from the lhs, eg.
114 | 'newtype' tycl_hdr '=' newconstr deriving
116 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
118 We provide comb3 and comb4 functions which are useful in such cases.
120 Be careful: there's no checking that you actually got this right, the
121 only symptom will be that the SrcSpans of your syntax will be
125 * We must expand these macros *before* running Happy, which is why this file is
126 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
128 #define L0 L noSrcSpan
129 #define L1 sL (getLoc $1)
130 #define LL sL (comb2 $1 $>)
132 -- -----------------------------------------------------------------------------
137 '_' { L _ ITunderscore } -- Haskell keywords
139 'case' { L _ ITcase }
140 'class' { L _ ITclass }
141 'data' { L _ ITdata }
142 'default' { L _ ITdefault }
143 'deriving' { L _ ITderiving }
145 'else' { L _ ITelse }
146 'hiding' { L _ IThiding }
148 'import' { L _ ITimport }
150 'infix' { L _ ITinfix }
151 'infixl' { L _ ITinfixl }
152 'infixr' { L _ ITinfixr }
153 'instance' { L _ ITinstance }
155 'module' { L _ ITmodule }
156 'newtype' { L _ ITnewtype }
158 'qualified' { L _ ITqualified }
159 'then' { L _ ITthen }
160 'type' { L _ ITtype }
161 'where' { L _ ITwhere }
162 '_scc_' { L _ ITscc } -- ToDo: remove
164 'forall' { L _ ITforall } -- GHC extension keywords
165 'foreign' { L _ ITforeign }
166 'export' { L _ ITexport }
167 'label' { L _ ITlabel }
168 'dynamic' { L _ ITdynamic }
169 'safe' { L _ ITsafe }
170 'threadsafe' { L _ ITthreadsafe }
171 'unsafe' { L _ ITunsafe }
173 'stdcall' { L _ ITstdcallconv }
174 'ccall' { L _ ITccallconv }
175 'dotnet' { L _ ITdotnet }
176 'proc' { L _ ITproc } -- for arrow notation extension
177 'rec' { L _ ITrec } -- for arrow notation extension
179 '{-# SPECIALISE' { L _ ITspecialise_prag }
180 '{-# SOURCE' { L _ ITsource_prag }
181 '{-# INLINE' { L _ ITinline_prag }
182 '{-# NOINLINE' { L _ ITnoinline_prag }
183 '{-# RULES' { L _ ITrules_prag }
184 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
185 '{-# SCC' { L _ ITscc_prag }
186 '{-# DEPRECATED' { L _ ITdeprecated_prag }
187 '{-# UNPACK' { L _ ITunpack_prag }
188 '#-}' { L _ ITclose_prag }
190 '..' { L _ ITdotdot } -- reserved symbols
192 '::' { L _ ITdcolon }
196 '<-' { L _ ITlarrow }
197 '->' { L _ ITrarrow }
200 '=>' { L _ ITdarrow }
204 '-<' { L _ ITlarrowtail } -- for arrow notation
205 '>-' { L _ ITrarrowtail } -- for arrow notation
206 '-<<' { L _ ITLarrowtail } -- for arrow notation
207 '>>-' { L _ ITRarrowtail } -- for arrow notation
210 '{' { L _ ITocurly } -- special symbols
212 '{|' { L _ ITocurlybar }
213 '|}' { L _ ITccurlybar }
214 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
215 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
218 '[:' { L _ ITopabrack }
219 ':]' { L _ ITcpabrack }
222 '(#' { L _ IToubxparen }
223 '#)' { L _ ITcubxparen }
224 '(|' { L _ IToparenbar }
225 '|)' { L _ ITcparenbar }
228 '`' { L _ ITbackquote }
230 VARID { L _ (ITvarid _) } -- identifiers
231 CONID { L _ (ITconid _) }
232 VARSYM { L _ (ITvarsym _) }
233 CONSYM { L _ (ITconsym _) }
234 QVARID { L _ (ITqvarid _) }
235 QCONID { L _ (ITqconid _) }
236 QVARSYM { L _ (ITqvarsym _) }
237 QCONSYM { L _ (ITqconsym _) }
239 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
240 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
242 CHAR { L _ (ITchar _) }
243 STRING { L _ (ITstring _) }
244 INTEGER { L _ (ITinteger _) }
245 RATIONAL { L _ (ITrational _) }
247 PRIMCHAR { L _ (ITprimchar _) }
248 PRIMSTRING { L _ (ITprimstring _) }
249 PRIMINTEGER { L _ (ITprimint _) }
250 PRIMFLOAT { L _ (ITprimfloat _) }
251 PRIMDOUBLE { L _ (ITprimdouble _) }
254 '[|' { L _ ITopenExpQuote }
255 '[p|' { L _ ITopenPatQuote }
256 '[t|' { L _ ITopenTypQuote }
257 '[d|' { L _ ITopenDecQuote }
258 '|]' { L _ ITcloseQuote }
259 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
260 '$(' { L _ ITparenEscape } -- $( exp )
261 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
262 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
264 %monad { P } { >>= } { return }
265 %lexer { lexer } { L _ ITeof }
266 %name parseModule module
267 %name parseStmt maybe_stmt
268 %name parseIdentifier identifier
269 %name parseIface iface
270 %name parseType ctype
271 %tokentype { Located Token }
274 -----------------------------------------------------------------------------
277 -- The place for module deprecation is really too restrictive, but if it
278 -- was allowed at its natural place just before 'module', we get an ugly
279 -- s/r conflict with the second alternative. Another solution would be the
280 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
281 -- either, and DEPRECATED is only expected to be used by people who really
282 -- know what they are doing. :-)
284 module :: { Located (HsModule RdrName) }
285 : 'module' modid maybemoddeprec maybeexports 'where' body
286 {% fileSrcSpan >>= \ loc ->
287 return (L loc (HsModule (Just (L (getLoc $2)
288 (mkHomeModule (unLoc $2))))
289 $4 (fst $6) (snd $6) $3)) }
290 | missing_module_keyword top close
291 {% fileSrcSpan >>= \ loc ->
292 return (L loc (HsModule Nothing Nothing
293 (fst $2) (snd $2) Nothing)) }
295 missing_module_keyword :: { () }
296 : {- empty -} {% pushCurrentContext }
298 maybemoddeprec :: { Maybe DeprecTxt }
299 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
300 | {- empty -} { Nothing }
302 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
304 | vocurly top close { $2 }
306 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
307 : importdecls { (reverse $1,[]) }
308 | importdecls ';' cvtopdecls { (reverse $1,$3) }
309 | cvtopdecls { ([],$1) }
311 cvtopdecls :: { [LHsDecl RdrName] }
312 : topdecls { cvTopDecls $1 }
314 -----------------------------------------------------------------------------
315 -- Interfaces (.hi-boot files)
317 iface :: { ModIface }
318 : 'module' modid 'where' ifacebody { mkBootIface (unLoc $2) $4 }
320 ifacebody :: { [HsDecl RdrName] }
321 : '{' ifacedecls '}' { $2 }
322 | vocurly ifacedecls close { $2 }
324 ifacedecls :: { [HsDecl RdrName] }
325 : ifacedecl ';' ifacedecls { $1 : $3 }
326 | ';' ifacedecls { $2 }
330 ifacedecl :: { HsDecl RdrName }
333 | 'type' syn_hdr '=' ctype
334 { let (tc,tvs) = $2 in TyClD (TySynonym tc tvs $4) }
335 | 'data' tycl_hdr constrs -- No deriving in hi-boot
336 { TyClD (mkTyData DataType (unLoc $2) (reverse (unLoc $3)) Nothing) }
337 | 'newtype' tycl_hdr -- Constructor is optional
338 { TyClD (mkTyData NewType (unLoc $2) [] Nothing) }
339 | 'newtype' tycl_hdr '=' newconstr
340 { TyClD (mkTyData NewType (unLoc $2) [$4] Nothing) }
341 | 'class' tycl_hdr fds
342 { TyClD (mkClassDecl (unLoc $2) (unLoc $3) [] emptyBag) }
344 -----------------------------------------------------------------------------
347 maybeexports :: { Maybe [LIE RdrName] }
348 : '(' exportlist ')' { Just $2 }
349 | {- empty -} { Nothing }
351 exportlist :: { [LIE RdrName] }
352 : exportlist ',' export { $3 : $1 }
353 | exportlist ',' { $1 }
357 -- No longer allow things like [] and (,,,) to be exported
358 -- They are built in syntax, always available
359 export :: { LIE RdrName }
360 : qvar { L1 (IEVar (unLoc $1)) }
361 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
362 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
363 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
364 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
365 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
367 qcnames :: { [RdrName] }
368 : qcnames ',' qcname { unLoc $3 : $1 }
369 | qcname { [unLoc $1] }
371 qcname :: { Located RdrName } -- Variable or data constructor
375 -----------------------------------------------------------------------------
376 -- Import Declarations
378 -- import decls can be *empty*, or even just a string of semicolons
379 -- whereas topdecls must contain at least one topdecl.
381 importdecls :: { [LImportDecl RdrName] }
382 : importdecls ';' importdecl { $3 : $1 }
383 | importdecls ';' { $1 }
384 | importdecl { [ $1 ] }
387 importdecl :: { LImportDecl RdrName }
388 : 'import' maybe_src optqualified modid maybeas maybeimpspec
389 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
391 maybe_src :: { IsBootInterface }
392 : '{-# SOURCE' '#-}' { True }
393 | {- empty -} { False }
395 optqualified :: { Bool }
396 : 'qualified' { True }
397 | {- empty -} { False }
399 maybeas :: { Located (Maybe ModuleName) }
400 : 'as' modid { LL (Just (unLoc $2)) }
401 | {- empty -} { noLoc Nothing }
403 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
404 : impspec { L1 (Just (unLoc $1)) }
405 | {- empty -} { noLoc Nothing }
407 impspec :: { Located (Bool, [LIE RdrName]) }
408 : '(' exportlist ')' { LL (False, reverse $2) }
409 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
411 -----------------------------------------------------------------------------
412 -- Fixity Declarations
416 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
418 infix :: { Located FixityDirection }
419 : 'infix' { L1 InfixN }
420 | 'infixl' { L1 InfixL }
421 | 'infixr' { L1 InfixR }
423 ops :: { Located [Located RdrName] }
424 : ops ',' op { LL ($3 : unLoc $1) }
427 -----------------------------------------------------------------------------
428 -- Top-Level Declarations
430 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
431 : topdecls ';' topdecl { $1 `appOL` $3 }
432 | topdecls ';' { $1 }
435 topdecl :: { OrdList (LHsDecl RdrName) }
436 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
437 | 'instance' inst_type where
438 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
439 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
440 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
441 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
442 | '{-# DEPRECATED' deprecations '#-}' { $2 }
443 | '{-# RULES' rules '#-}' { $2 }
444 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
447 tycl_decl :: { LTyClDecl RdrName }
448 : 'type' syn_hdr '=' ctype
449 -- Note ctype, not sigtype.
450 -- We allow an explicit for-all but we don't insert one
451 -- in type Foo a = (b,b)
452 -- Instead we just say b is out of scope
453 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
455 | 'data' tycl_hdr constrs deriving
456 { L (comb4 $1 $2 $3 $4)
457 (mkTyData DataType (unLoc $2) (reverse (unLoc $3)) (unLoc $4)) }
459 | 'newtype' tycl_hdr '=' newconstr deriving
461 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
463 | 'class' tycl_hdr fds where
465 (binds,sigs) = cvBindsAndSigs (unLoc $4)
467 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
470 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
471 -- We don't retain the syntax of an infix
472 -- type synonym declaration. Oh well.
473 : tycon tv_bndrs { ($1, $2) }
474 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
476 -- tycl_hdr parses the header of a type or class decl,
477 -- which takes the form
480 -- (Eq a, Ord b) => T a b
481 -- Rather a lot of inlining here, else we get reduce/reduce errors
482 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
483 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
484 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
486 -----------------------------------------------------------------------------
487 -- Nested declarations
489 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
490 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
491 | decls ';' { LL (unLoc $1) }
493 | {- empty -} { noLoc nilOL }
496 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
497 : '{' decls '}' { LL (unLoc $2) }
498 | vocurly decls close { $2 }
500 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
501 -- No implicit parameters
502 : 'where' decllist { LL (unLoc $2) }
503 | {- empty -} { noLoc nilOL }
505 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
506 : decllist { L1 [cvBindGroup (unLoc $1)] }
507 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
508 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
510 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
511 : 'where' binds { LL (unLoc $2) }
512 | {- empty -} { noLoc [] }
515 -----------------------------------------------------------------------------
516 -- Transformation Rules
518 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
519 : rules ';' rule { $1 `snocOL` $3 }
522 | {- empty -} { nilOL }
524 rule :: { LHsDecl RdrName }
525 : STRING activation rule_forall infixexp '=' exp
526 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
528 activation :: { Activation } -- Omitted means AlwaysActive
529 : {- empty -} { AlwaysActive }
530 | explicit_activation { $1 }
532 inverse_activation :: { Activation } -- Omitted means NeverActive
533 : {- empty -} { NeverActive }
534 | explicit_activation { $1 }
536 explicit_activation :: { Activation } -- In brackets
537 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
538 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
540 rule_forall :: { [RuleBndr RdrName] }
541 : 'forall' rule_var_list '.' { $2 }
544 rule_var_list :: { [RuleBndr RdrName] }
546 | rule_var rule_var_list { $1 : $2 }
548 rule_var :: { RuleBndr RdrName }
549 : varid { RuleBndr $1 }
550 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
552 -----------------------------------------------------------------------------
553 -- Deprecations (c.f. rules)
555 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
556 : deprecations ';' deprecation { $1 `appOL` $3 }
557 | deprecations ';' { $1 }
559 | {- empty -} { nilOL }
561 -- SUP: TEMPORARY HACK, not checking for `module Foo'
562 deprecation :: { OrdList (LHsDecl RdrName) }
564 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
568 -----------------------------------------------------------------------------
569 -- Foreign import and export declarations
571 -- for the time being, the following accepts foreign declarations conforming
572 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
574 -- * a flag indicates whether pre-standard declarations have been used and
575 -- triggers a deprecation warning further down the road
577 -- NB: The first two rules could be combined into one by replacing `safety1'
578 -- with `safety'. However, the combined rule conflicts with the
581 fdecl :: { LHsDecl RdrName }
582 fdecl : 'import' callconv safety1 fspec
583 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
584 | 'import' callconv fspec
585 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
587 | 'export' callconv fspec
588 {% mkExport $2 (unLoc $3) >>= return.LL }
589 -- the following syntax is DEPRECATED
590 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
591 | fdecl2DEPRECATED { L1 (unLoc $1) }
593 fdecl1DEPRECATED :: { LForeignDecl RdrName }
595 ----------- DEPRECATED label decls ------------
596 : 'label' ext_name varid '::' sigtype
597 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
598 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
600 ----------- DEPRECATED ccall/stdcall decls ------------
602 -- NB: This business with the case expression below may seem overly
603 -- complicated, but it is necessary to avoid some conflicts.
605 -- DEPRECATED variant #1: lack of a calling convention specification
607 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
609 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
611 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
612 (CFunction target)) True }
614 -- DEPRECATED variant #2: external name consists of two separate strings
615 -- (module name and function name) (import)
616 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
618 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
619 CCall cconv -> return $
621 imp = CFunction (StaticTarget (getSTRING $4))
623 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
625 -- DEPRECATED variant #3: `unsafe' after entity
626 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
628 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
629 CCall cconv -> return $
631 imp = CFunction (StaticTarget (getSTRING $3))
633 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
635 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
636 -- an explicit calling convention (import)
637 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
638 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
639 (CFunction DynamicTarget)) True }
641 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
642 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
644 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
645 CCall cconv -> return $
646 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
647 (CFunction DynamicTarget)) True }
649 -- DEPRECATED variant #6: lack of a calling convention specification
651 | 'export' {-no callconv-} ext_name varid '::' sigtype
652 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
653 defaultCCallConv)) True }
655 -- DEPRECATED variant #7: external name consists of two separate strings
656 -- (module name and function name) (export)
657 | 'export' callconv STRING STRING varid '::' sigtype
659 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
660 CCall cconv -> return $
661 LL $ ForeignExport $5 $7
662 (CExport (CExportStatic (getSTRING $4) cconv)) True }
664 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
665 -- an explicit calling convention (export)
666 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
667 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
670 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
671 | 'export' callconv 'dynamic' varid '::' sigtype
673 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
674 CCall cconv -> return $
675 LL $ ForeignImport $4 $6
676 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
678 ----------- DEPRECATED .NET decls ------------
679 -- NB: removed the .NET call declaration, as it is entirely subsumed
680 -- by the new standard FFI declarations
682 fdecl2DEPRECATED :: { LHsDecl RdrName }
684 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
685 -- left this one unchanged for the moment as type imports are not
686 -- covered currently by the FFI standard -=chak
689 callconv :: { CallConv }
690 : 'stdcall' { CCall StdCallConv }
691 | 'ccall' { CCall CCallConv }
692 | 'dotnet' { DNCall }
695 : 'unsafe' { PlayRisky }
696 | 'safe' { PlaySafe False }
697 | 'threadsafe' { PlaySafe True }
698 | {- empty -} { PlaySafe False }
700 safety1 :: { Safety }
701 : 'unsafe' { PlayRisky }
702 | 'safe' { PlaySafe False }
703 | 'threadsafe' { PlaySafe True }
704 -- only needed to avoid conflicts with the DEPRECATED rules
706 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
707 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
708 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
709 -- if the entity string is missing, it defaults to the empty string;
710 -- the meaning of an empty entity string depends on the calling
714 ext_name :: { Maybe CLabelString }
715 : STRING { Just (getSTRING $1) }
716 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
717 | {- empty -} { Nothing }
720 -----------------------------------------------------------------------------
723 opt_sig :: { Maybe (LHsType RdrName) }
724 : {- empty -} { Nothing }
725 | '::' sigtype { Just $2 }
727 opt_asig :: { Maybe (LHsType RdrName) }
728 : {- empty -} { Nothing }
729 | '::' atype { Just $2 }
731 sigtypes1 :: { [LHsType RdrName] }
733 | sigtype ',' sigtypes1 { $1 : $3 }
735 sigtype :: { LHsType RdrName }
736 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
737 -- Wrap an Implicit forall if there isn't one there already
739 sig_vars :: { Located [Located RdrName] }
740 : sig_vars ',' var { LL ($3 : unLoc $1) }
743 -----------------------------------------------------------------------------
746 -- A ctype is a for-all type
747 ctype :: { LHsType RdrName }
748 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
749 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
750 -- A type of form (context => type) is an *implicit* HsForAllTy
753 -- We parse a context as a btype so that we don't get reduce/reduce
754 -- errors in ctype. The basic problem is that
756 -- looks so much like a tuple type. We can't tell until we find the =>
757 context :: { LHsContext RdrName }
758 : btype {% checkContext $1 }
760 type :: { LHsType RdrName }
761 : ipvar '::' gentype { LL (HsPredTy (HsIParam (unLoc $1) $3)) }
764 gentype :: { LHsType RdrName }
766 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
767 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
768 | btype '->' gentype { LL $ HsFunTy $1 $3 }
770 btype :: { LHsType RdrName }
771 : btype atype { LL $ HsAppTy $1 $2 }
774 atype :: { LHsType RdrName }
775 : gtycon { L1 (HsTyVar (unLoc $1)) }
776 | tyvar { L1 (HsTyVar (unLoc $1)) }
777 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
778 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
779 | '[' type ']' { LL $ HsListTy $2 }
780 | '[:' type ':]' { LL $ HsPArrTy $2 }
781 | '(' ctype ')' { LL $ HsParTy $2 }
782 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
784 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
786 -- An inst_type is what occurs in the head of an instance decl
787 -- e.g. (Foo a, Gaz b) => Wibble a b
788 -- It's kept as a single type, with a MonoDictTy at the right
789 -- hand corner, for convenience.
790 inst_type :: { LHsType RdrName }
791 : ctype {% checkInstType $1 }
793 inst_types1 :: { [LHsType RdrName] }
795 | inst_type ',' inst_types1 { $1 : $3 }
797 comma_types0 :: { [LHsType RdrName] }
798 : comma_types1 { $1 }
801 comma_types1 :: { [LHsType RdrName] }
803 | type ',' comma_types1 { $1 : $3 }
805 tv_bndrs :: { [LHsTyVarBndr RdrName] }
806 : tv_bndr tv_bndrs { $1 : $2 }
809 tv_bndr :: { LHsTyVarBndr RdrName }
810 : tyvar { L1 (UserTyVar (unLoc $1)) }
811 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
813 fds :: { Located [Located ([RdrName], [RdrName])] }
814 : {- empty -} { noLoc [] }
815 | '|' fds1 { LL (reverse (unLoc $2)) }
817 fds1 :: { Located [Located ([RdrName], [RdrName])] }
818 : fds1 ',' fd { LL ($3 : unLoc $1) }
821 fd :: { Located ([RdrName], [RdrName]) }
822 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
823 (reverse (unLoc $1), reverse (unLoc $3)) }
825 varids0 :: { Located [RdrName] }
826 : {- empty -} { noLoc [] }
827 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
829 -----------------------------------------------------------------------------
834 | akind '->' kind { mkArrowKind $1 $3 }
837 : '*' { liftedTypeKind }
838 | '(' kind ')' { $2 }
841 -----------------------------------------------------------------------------
842 -- Datatype declarations
844 newconstr :: { LConDecl RdrName }
845 : conid atype { LL $ ConDecl $1 [] (noLoc [])
846 (PrefixCon [(unbangedType $2)]) }
847 | conid '{' var '::' ctype '}'
848 { LL $ ConDecl $1 [] (noLoc [])
849 (RecCon [($3, (unbangedType $5))]) }
851 constrs :: { Located [LConDecl RdrName] }
852 : {- empty; a GHC extension -} { noLoc [] }
853 | '=' constrs1 { LL (unLoc $2) }
855 constrs1 :: { Located [LConDecl RdrName] }
856 : constrs1 '|' constr { LL ($3 : unLoc $1) }
859 constr :: { LConDecl RdrName }
860 : forall context '=>' constr_stuff
861 { let (con,details) = unLoc $4 in
862 LL (ConDecl con (unLoc $1) $2 details) }
863 | forall constr_stuff
864 { let (con,details) = unLoc $2 in
865 LL (ConDecl con (unLoc $1) (noLoc []) details) }
867 forall :: { Located [LHsTyVarBndr RdrName] }
868 : 'forall' tv_bndrs '.' { LL $2 }
869 | {- empty -} { noLoc [] }
871 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
872 : btype {% mkPrefixCon $1 [] >>= return.LL }
873 | btype bang_atype satypes {% do { r <- mkPrefixCon $1 ($2 : unLoc $3);
874 return (L (comb3 $1 $2 $3) r) } }
875 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
876 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
877 | sbtype conop sbtype { LL ($2, InfixCon $1 $3) }
879 bang_atype :: { LBangType RdrName }
880 : strict_mark atype { LL (BangType (unLoc $1) $2) }
882 satypes :: { Located [LBangType RdrName] }
883 : atype satypes { LL (unbangedType $1 : unLoc $2) }
884 | bang_atype satypes { LL ($1 : unLoc $2) }
885 | {- empty -} { noLoc [] }
887 sbtype :: { LBangType RdrName }
888 : btype { unbangedType $1 }
889 | strict_mark atype { LL (BangType (unLoc $1) $2) }
891 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
892 : fielddecl ',' fielddecls { unLoc $1 : $3 }
893 | fielddecl { [unLoc $1] }
895 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
896 : sig_vars '::' stype { LL (reverse (unLoc $1), $3) }
898 stype :: { LBangType RdrName }
899 : ctype { unbangedType $1 }
900 | strict_mark atype { LL (BangType (unLoc $1) $2) }
902 strict_mark :: { Located HsBang }
903 : '!' { L1 HsStrict }
904 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
906 -- We allow the odd-looking 'inst_type' in a deriving clause, so that
907 -- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
908 -- The 'C [a]' part is converted to an HsPredTy by checkInstType
909 -- We don't allow a context, but that's sorted out by the type checker.
910 deriving :: { Located (Maybe [LHsType RdrName]) }
911 : {- empty -} { noLoc Nothing }
912 | 'deriving' qtycon {% do { let { L loc tv = $2 }
913 ; p <- checkInstType (L loc (HsTyVar tv))
914 ; return (LL (Just [p])) } }
915 | 'deriving' '(' ')' { LL (Just []) }
916 | 'deriving' '(' inst_types1 ')' { LL (Just $3) }
917 -- Glasgow extension: allow partial
918 -- applications in derivings
920 -----------------------------------------------------------------------------
923 {- There's an awkward overlap with a type signature. Consider
924 f :: Int -> Int = ...rhs...
925 Then we can't tell whether it's a type signature or a value
926 definition with a result signature until we see the '='.
927 So we have to inline enough to postpone reductions until we know.
931 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
932 instead of qvar, we get another shift/reduce-conflict. Consider the
935 { (^^) :: Int->Int ; } Type signature; only var allowed
937 { (^^) :: Int->Int = ... ; } Value defn with result signature;
938 qvar allowed (because of instance decls)
940 We can't tell whether to reduce var to qvar until after we've read the signatures.
943 decl :: { Located (OrdList (LHsDecl RdrName)) }
945 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 (unLoc $3);
946 return (LL $ unitOL (LL $ ValD r)) } }
948 rhs :: { Located (GRHSs RdrName) }
949 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) placeHolderType }
950 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) placeHolderType }
952 gdrhs :: { Located [LGRHS RdrName] }
953 : gdrhs gdrh { LL ($2 : unLoc $1) }
956 gdrh :: { LGRHS RdrName }
957 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
960 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
961 : infixexp '::' sigtype
962 {% do s <- checkValSig $1 $3;
963 return (LL $ unitOL (LL $ SigD s)) }
964 -- See the above notes for why we need infixexp here
965 | var ',' sig_vars '::' sigtype
966 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
967 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
969 | '{-# INLINE' activation qvar '#-}'
970 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
971 | '{-# NOINLINE' inverse_activation qvar '#-}'
972 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
973 | '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
974 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
976 | '{-# SPECIALISE' 'instance' inst_type '#-}'
977 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
979 -----------------------------------------------------------------------------
982 exp :: { LHsExpr RdrName }
983 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
984 | infixexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
985 | infixexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
986 | infixexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
987 | infixexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
990 infixexp :: { LHsExpr RdrName }
992 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
994 exp10 :: { LHsExpr RdrName }
995 : '\\' aexp aexps opt_asig '->' exp
996 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
997 return (LL $ HsLam (LL $ Match ps $4
998 (GRHSs (unguardedRHS $6) []
1000 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
1001 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
1002 | 'case' exp 'of' altslist { LL $ HsCase $2 (unLoc $4) }
1003 | '-' fexp { LL $ mkHsNegApp $2 }
1005 | 'do' stmtlist {% let loc = comb2 $1 $2 in
1006 checkDo loc (unLoc $2) >>= \ stmts ->
1007 return (L loc (mkHsDo DoExpr stmts)) }
1008 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
1009 checkMDo loc (unLoc $2) >>= \ stmts ->
1010 return (L loc (mkHsDo MDoExpr stmts)) }
1012 | scc_annot exp { LL $ if opt_SccProfilingOn
1013 then HsSCC (unLoc $1) $2
1016 | 'proc' aexp '->' exp
1017 {% checkPattern $2 >>= \ p ->
1018 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1019 placeHolderType undefined)) }
1020 -- TODO: is LL right here?
1022 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1023 -- hdaume: core annotation
1026 scc_annot :: { Located FastString }
1027 : '_scc_' STRING { LL $ getSTRING $2 }
1028 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1030 fexp :: { LHsExpr RdrName }
1031 : fexp aexp { LL $ HsApp $1 $2 }
1034 aexps :: { [LHsExpr RdrName] }
1035 : aexps aexp { $2 : $1 }
1036 | {- empty -} { [] }
1038 aexp :: { LHsExpr RdrName }
1039 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1040 | '~' aexp { LL $ ELazyPat $2 }
1043 aexp1 :: { LHsExpr RdrName }
1044 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1049 -- Here was the syntax for type applications that I was planning
1050 -- but there are difficulties (e.g. what order for type args)
1051 -- so it's not enabled yet.
1052 -- But this case *is* used for the left hand side of a generic definition,
1053 -- which is parsed as an expression before being munged into a pattern
1054 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1055 (sL (getLoc $3) (HsType $3)) }
1057 aexp2 :: { LHsExpr RdrName }
1058 : ipvar { L1 (HsIPVar $! unLoc $1) }
1059 | qcname { L1 (HsVar $! unLoc $1) }
1060 | literal { L1 (HsLit $! unLoc $1) }
1061 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1062 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1063 | '(' exp ')' { LL (HsPar $2) }
1064 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1065 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1066 | '[' list ']' { LL (unLoc $2) }
1067 | '[:' parr ':]' { LL (unLoc $2) }
1068 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1069 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1070 | '_' { L1 EWildPat }
1072 -- MetaHaskell Extension
1073 | TH_ID_SPLICE { L1 $ HsSpliceE (mkHsSplice
1074 (L1 $ HsVar (mkUnqual varName
1075 (getTH_ID_SPLICE $1)))) } -- $x
1076 | '$(' exp ')' { LL $ HsSpliceE (mkHsSplice $2) } -- $( exp )
1078 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1079 | TH_VAR_QUOTE gcon { LL $ HsBracket (VarBr (unLoc $2)) }
1080 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1081 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1082 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1083 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1084 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1085 return (LL $ HsBracket (PatBr p)) }
1086 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1088 -- arrow notation extension
1089 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1091 cmdargs :: { [LHsCmdTop RdrName] }
1092 : cmdargs acmd { $2 : $1 }
1093 | {- empty -} { [] }
1095 acmd :: { LHsCmdTop RdrName }
1096 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1098 cvtopbody :: { [LHsDecl RdrName] }
1099 : '{' cvtopdecls0 '}' { $2 }
1100 | vocurly cvtopdecls0 close { $2 }
1102 cvtopdecls0 :: { [LHsDecl RdrName] }
1103 : {- empty -} { [] }
1106 texps :: { [LHsExpr RdrName] }
1107 : texps ',' exp { $3 : $1 }
1111 -----------------------------------------------------------------------------
1114 -- The rules below are little bit contorted to keep lexps left-recursive while
1115 -- avoiding another shift/reduce-conflict.
1117 list :: { LHsExpr RdrName }
1118 : exp { L1 $ ExplicitList placeHolderType [$1] }
1119 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1120 | exp '..' { LL $ ArithSeqIn (From $1) }
1121 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1122 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1123 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1124 | exp pquals { LL $ mkHsDo ListComp
1125 (reverse (L (getLoc $1) (ResultStmt $1) :
1128 lexps :: { Located [LHsExpr RdrName] }
1129 : lexps ',' exp { LL ($3 : unLoc $1) }
1130 | exp ',' exp { LL [$3,$1] }
1132 -----------------------------------------------------------------------------
1133 -- List Comprehensions
1135 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1136 -- or a reversed list of Stmts
1137 : pquals1 { case unLoc $1 of
1139 qss -> L1 [L1 (ParStmt stmtss)]
1141 stmtss = [ (reverse qs, undefined)
1145 pquals1 :: { Located [[LStmt RdrName]] }
1146 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1147 | '|' quals { L (getLoc $2) [unLoc $2] }
1149 quals :: { Located [LStmt RdrName] }
1150 : quals ',' qual { LL ($3 : unLoc $1) }
1153 -----------------------------------------------------------------------------
1154 -- Parallel array expressions
1156 -- The rules below are little bit contorted; see the list case for details.
1157 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1158 -- Moreover, we allow explicit arrays with no element (represented by the nil
1159 -- constructor in the list case).
1161 parr :: { LHsExpr RdrName }
1162 : { noLoc (ExplicitPArr placeHolderType []) }
1163 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1164 | lexps { L1 $ ExplicitPArr placeHolderType
1165 (reverse (unLoc $1)) }
1166 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1167 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1168 | exp pquals { LL $ mkHsDo PArrComp
1169 (reverse (L (getLoc $1) (ResultStmt $1) :
1173 -- We are reusing `lexps' and `pquals' from the list case.
1175 -----------------------------------------------------------------------------
1176 -- Case alternatives
1178 altslist :: { Located [LMatch RdrName] }
1179 : '{' alts '}' { LL (reverse (unLoc $2)) }
1180 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1182 alts :: { Located [LMatch RdrName] }
1183 : alts1 { L1 (unLoc $1) }
1184 | ';' alts { LL (unLoc $2) }
1186 alts1 :: { Located [LMatch RdrName] }
1187 : alts1 ';' alt { LL ($3 : unLoc $1) }
1188 | alts1 ';' { LL (unLoc $1) }
1191 alt :: { LMatch RdrName }
1192 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1193 return (LL (Match [p] $2 (unLoc $3))) }
1195 alt_rhs :: { Located (GRHSs RdrName) }
1196 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)
1199 ralt :: { Located [LGRHS RdrName] }
1200 : '->' exp { LL (unguardedRHS $2) }
1201 | gdpats { L1 (reverse (unLoc $1)) }
1203 gdpats :: { Located [LGRHS RdrName] }
1204 : gdpats gdpat { LL ($2 : unLoc $1) }
1207 gdpat :: { LGRHS RdrName }
1208 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1209 in LL $ GRHS (reverse (r : unLoc $2)) }
1211 -----------------------------------------------------------------------------
1212 -- Statement sequences
1214 stmtlist :: { Located [LStmt RdrName] }
1215 : '{' stmts '}' { LL (unLoc $2) }
1216 | vocurly stmts close { $2 }
1218 -- do { ;; s ; s ; ; s ;; }
1219 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1220 -- here, because we need too much lookahead if we see do { e ; }
1221 -- So we use ExprStmts throughout, and switch the last one over
1222 -- in ParseUtils.checkDo instead
1223 stmts :: { Located [LStmt RdrName] }
1224 : stmt stmts_help { LL ($1 : unLoc $2) }
1225 | ';' stmts { LL (unLoc $2) }
1226 | {- empty -} { noLoc [] }
1228 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1229 : ';' stmts { LL (unLoc $2) }
1230 | {- empty -} { noLoc [] }
1232 -- For typing stmts at the GHCi prompt, where
1233 -- the input may consist of just comments.
1234 maybe_stmt :: { Maybe (LStmt RdrName) }
1236 | {- nothing -} { Nothing }
1238 stmt :: { LStmt RdrName }
1240 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1241 return (LL $ BindStmt p $1) }
1242 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1244 qual :: { LStmt RdrName }
1245 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1246 return (LL $ BindStmt p $3) }
1247 | exp { L1 $ ExprStmt $1 placeHolderType }
1248 | 'let' binds { LL $ LetStmt (unLoc $2) }
1250 -----------------------------------------------------------------------------
1251 -- Record Field Update/Construction
1253 fbinds :: { HsRecordBinds RdrName }
1255 | {- empty -} { [] }
1257 fbinds1 :: { HsRecordBinds RdrName }
1258 : fbinds1 ',' fbind { $3 : $1 }
1261 fbind :: { (Located RdrName, LHsExpr RdrName) }
1262 : qvar '=' exp { ($1,$3) }
1264 -----------------------------------------------------------------------------
1265 -- Implicit Parameter Bindings
1267 dbinds :: { Located [LIPBind RdrName] }
1268 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1269 | dbinds ';' { LL (unLoc $1) }
1271 -- | {- empty -} { [] }
1273 dbind :: { LIPBind RdrName }
1274 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1276 -----------------------------------------------------------------------------
1277 -- Variables, Constructors and Operators.
1279 identifier :: { Located RdrName }
1285 depreclist :: { Located [RdrName] }
1286 depreclist : deprec_var { L1 [unLoc $1] }
1287 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1289 deprec_var :: { Located RdrName }
1290 deprec_var : var { $1 }
1293 gcon :: { Located RdrName } -- Data constructor namespace
1294 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1296 -- the case of '[:' ':]' is part of the production `parr'
1298 sysdcon :: { Located DataCon } -- Wired in data constructors
1299 : '(' ')' { LL unitDataCon }
1300 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1301 | '[' ']' { LL nilDataCon }
1303 var :: { Located RdrName }
1305 | '(' varsym ')' { LL (unLoc $2) }
1307 qvar :: { Located RdrName }
1309 | '(' varsym ')' { LL (unLoc $2) }
1310 | '(' qvarsym1 ')' { LL (unLoc $2) }
1311 -- We've inlined qvarsym here so that the decision about
1312 -- whether it's a qvar or a var can be postponed until
1313 -- *after* we see the close paren.
1315 ipvar :: { Located (IPName RdrName) }
1316 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1317 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1319 qcon :: { Located RdrName }
1321 | '(' qconsym ')' { LL (unLoc $2) }
1323 varop :: { Located RdrName }
1325 | '`' varid '`' { LL (unLoc $2) }
1327 qvarop :: { Located RdrName }
1329 | '`' qvarid '`' { LL (unLoc $2) }
1331 qvaropm :: { Located RdrName }
1332 : qvarsym_no_minus { $1 }
1333 | '`' qvarid '`' { LL (unLoc $2) }
1335 conop :: { Located RdrName }
1337 | '`' conid '`' { LL (unLoc $2) }
1339 qconop :: { Located RdrName }
1341 | '`' qconid '`' { LL (unLoc $2) }
1343 -----------------------------------------------------------------------------
1344 -- Type constructors
1346 gtycon :: { Located RdrName } -- A "general" qualified tycon
1348 | '(' ')' { LL $ getRdrName unitTyCon }
1349 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1350 | '(' '->' ')' { LL $ getRdrName funTyCon }
1351 | '[' ']' { LL $ listTyCon_RDR }
1352 | '[:' ':]' { LL $ parrTyCon_RDR }
1354 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1356 | '(' qtyconsym ')' { LL (unLoc $2) }
1358 qtyconop :: { Located RdrName } -- Qualified or unqualified
1360 | '`' qtycon '`' { LL (unLoc $2) }
1362 tyconop :: { Located RdrName } -- Unqualified
1364 | '`' tycon '`' { LL (unLoc $2) }
1366 qtycon :: { Located RdrName } -- Qualified or unqualified
1367 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1370 tycon :: { Located RdrName } -- Unqualified
1371 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1373 qtyconsym :: { Located RdrName }
1374 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1377 tyconsym :: { Located RdrName }
1378 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1380 -----------------------------------------------------------------------------
1383 op :: { Located RdrName } -- used in infix decls
1387 qop :: { LHsExpr RdrName } -- used in sections
1388 : qvarop { L1 $ HsVar (unLoc $1) }
1389 | qconop { L1 $ HsVar (unLoc $1) }
1391 qopm :: { LHsExpr RdrName } -- used in sections
1392 : qvaropm { L1 $ HsVar (unLoc $1) }
1393 | qconop { L1 $ HsVar (unLoc $1) }
1395 -----------------------------------------------------------------------------
1398 qvarid :: { Located RdrName }
1400 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1402 varid :: { Located RdrName }
1403 : varid_no_unsafe { $1 }
1404 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1405 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1406 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1408 varid_no_unsafe :: { Located RdrName }
1409 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1410 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1411 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1413 tyvar :: { Located RdrName }
1414 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1415 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1416 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1417 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1418 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1420 -- These special_ids are treated as keywords in various places,
1421 -- but as ordinary ids elsewhere. 'special_id' collects all these
1422 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1423 special_id :: { Located UserFS }
1425 : 'as' { L1 FSLIT("as") }
1426 | 'qualified' { L1 FSLIT("qualified") }
1427 | 'hiding' { L1 FSLIT("hiding") }
1428 | 'export' { L1 FSLIT("export") }
1429 | 'label' { L1 FSLIT("label") }
1430 | 'dynamic' { L1 FSLIT("dynamic") }
1431 | 'stdcall' { L1 FSLIT("stdcall") }
1432 | 'ccall' { L1 FSLIT("ccall") }
1434 -----------------------------------------------------------------------------
1437 qvarsym :: { Located RdrName }
1441 qvarsym_no_minus :: { Located RdrName }
1442 : varsym_no_minus { $1 }
1445 qvarsym1 :: { Located RdrName }
1446 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1448 varsym :: { Located RdrName }
1449 : varsym_no_minus { $1 }
1450 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1452 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1453 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1454 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1457 -- See comments with special_id
1458 special_sym :: { Located UserFS }
1459 special_sym : '!' { L1 FSLIT("!") }
1460 | '.' { L1 FSLIT(".") }
1461 | '*' { L1 FSLIT("*") }
1463 -----------------------------------------------------------------------------
1464 -- Data constructors
1466 qconid :: { Located RdrName } -- Qualified or unqualifiedb
1468 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1470 conid :: { Located RdrName }
1471 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1473 qconsym :: { Located RdrName } -- Qualified or unqualified
1475 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1477 consym :: { Located RdrName }
1478 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1480 -- ':' means only list cons
1481 | ':' { L1 $ consDataCon_RDR }
1484 -----------------------------------------------------------------------------
1487 literal :: { Located HsLit }
1488 : CHAR { L1 $ HsChar $ getCHAR $1 }
1489 | STRING { L1 $ HsString $ getSTRING $1 }
1490 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1491 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1492 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1493 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1494 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1496 -----------------------------------------------------------------------------
1500 : vccurly { () } -- context popped in lexer.
1501 | error {% popContext }
1503 -----------------------------------------------------------------------------
1504 -- Miscellaneous (mostly renamings)
1506 modid :: { Located ModuleName }
1507 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1508 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1511 (unpackFS mod ++ '.':unpackFS c))
1515 : commas ',' { $1 + 1 }
1518 -----------------------------------------------------------------------------
1522 happyError = srcParseFail
1524 getVARID (L _ (ITvarid x)) = x
1525 getCONID (L _ (ITconid x)) = x
1526 getVARSYM (L _ (ITvarsym x)) = x
1527 getCONSYM (L _ (ITconsym x)) = x
1528 getQVARID (L _ (ITqvarid x)) = x
1529 getQCONID (L _ (ITqconid x)) = x
1530 getQVARSYM (L _ (ITqvarsym x)) = x
1531 getQCONSYM (L _ (ITqconsym x)) = x
1532 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1533 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1534 getCHAR (L _ (ITchar x)) = x
1535 getSTRING (L _ (ITstring x)) = x
1536 getINTEGER (L _ (ITinteger x)) = x
1537 getRATIONAL (L _ (ITrational x)) = x
1538 getPRIMCHAR (L _ (ITprimchar x)) = x
1539 getPRIMSTRING (L _ (ITprimstring x)) = x
1540 getPRIMINTEGER (L _ (ITprimint x)) = x
1541 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1542 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1543 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1545 -- Utilities for combining source spans
1546 comb2 :: Located a -> Located b -> SrcSpan
1549 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1550 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1552 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1553 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1554 combineSrcSpans (getLoc c) (getLoc d)
1556 -- strict constructor version:
1558 sL :: SrcSpan -> a -> Located a
1559 sL span a = span `seq` L span a
1561 -- Make a source location for the file. We're a bit lazy here and just
1562 -- make a point SrcSpan at line 1, column 0. Strictly speaking we should
1563 -- try to find the span of the whole file (ToDo).
1564 fileSrcSpan :: P SrcSpan
1567 let loc = mkSrcLoc (srcLocFile l) 1 0;
1568 return (mkSrcSpan loc loc)