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 ) 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, mkGeneralSrcSpan, srcLocFile )
32 import CmdLineOpts ( opt_SccProfilingOn )
33 import Type ( Kind, mkArrowKind, liftedTypeKind )
34 import BasicTypes ( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
35 NewOrData(..), Activation(..) )
37 import Bag ( emptyBag )
41 import CStrings ( CLabelString )
43 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 8 for ambiguity in 'e :: a `b` c'. Does this mean [States 160,246]
65 1 for ambiguity in 'let ?x ...' [State 268]
66 the parser can't tell whether the ?x is the lhs of a normal binding or
67 an implicit binding. Fortunately resolving as shift gives it the only
68 sensible meaning, namely the lhs of an implicit binding.
70 1 for ambiguity in '{-# RULES "name" [ ... #-} [State 332]
71 we don't know whether the '[' starts the activation or not: it
72 might be the start of the declaration with the activation being
75 1 for ambiguity in '{-# RULES "name" forall = ... #-}' [State 394]
76 since 'forall' is a valid variable name, we don't know whether
77 to treat a forall on the input as the beginning of a quantifier
78 or the beginning of the rule itself. Resolving to shift means
79 it's always treated as a quantifier, hence the above is disallowed.
80 This saves explicitly defining a grammar for the rule lhs that
81 doesn't include 'forall'.
83 6 for conflicts between `fdecl' and `fdeclDEPRECATED', [States 384,385]
84 which are resolved correctly, and moreover,
85 should go away when `fdeclDEPRECATED' is removed.
87 -- ---------------------------------------------------------------------------
88 -- Adding location info
90 This is done in a stylised way using the three macros below, L0, L1
91 and LL. Each of these macros can be thought of as having type
93 L0, L1, LL :: a -> Located a
95 They each add a SrcSpan to their argument.
97 L0 adds 'noSrcSpan', used for empty productions
99 L1 for a production with a single token on the lhs. Grabs the SrcSpan
102 LL for a production with >1 token on the lhs. Makes up a SrcSpan from
103 the first and last tokens.
105 These suffice for the majority of cases. However, we must be
106 especially careful with empty productions: LL won't work if the first
107 or last token on the lhs can represent an empty span. In these cases,
108 we have to calculate the span using more of the tokens from the lhs, eg.
110 | 'newtype' tycl_hdr '=' newconstr deriving
112 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
114 We provide comb3 and comb4 functions which are useful in such cases.
116 Be careful: there's no checking that you actually got this right, the
117 only symptom will be that the SrcSpans of your syntax will be
121 * We must expand these macros *before* running Happy, which is why this file is
122 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
124 #define L0 L noSrcSpan
125 #define L1 sL (getLoc $1)
126 #define LL sL (comb2 $1 $>)
128 -- -----------------------------------------------------------------------------
133 '_' { L _ ITunderscore } -- Haskell keywords
135 'case' { L _ ITcase }
136 'class' { L _ ITclass }
137 'data' { L _ ITdata }
138 'default' { L _ ITdefault }
139 'deriving' { L _ ITderiving }
141 'else' { L _ ITelse }
142 'hiding' { L _ IThiding }
144 'import' { L _ ITimport }
146 'infix' { L _ ITinfix }
147 'infixl' { L _ ITinfixl }
148 'infixr' { L _ ITinfixr }
149 'instance' { L _ ITinstance }
151 'module' { L _ ITmodule }
152 'newtype' { L _ ITnewtype }
154 'qualified' { L _ ITqualified }
155 'then' { L _ ITthen }
156 'type' { L _ ITtype }
157 'where' { L _ ITwhere }
158 '_scc_' { L _ ITscc } -- ToDo: remove
160 'forall' { L _ ITforall } -- GHC extension keywords
161 'foreign' { L _ ITforeign }
162 'export' { L _ ITexport }
163 'label' { L _ ITlabel }
164 'dynamic' { L _ ITdynamic }
165 'safe' { L _ ITsafe }
166 'threadsafe' { L _ ITthreadsafe }
167 'unsafe' { L _ ITunsafe }
169 'stdcall' { L _ ITstdcallconv }
170 'ccall' { L _ ITccallconv }
171 'dotnet' { L _ ITdotnet }
172 'proc' { L _ ITproc } -- for arrow notation extension
173 'rec' { L _ ITrec } -- for arrow notation extension
175 '{-# SPECIALISE' { L _ ITspecialise_prag }
176 '{-# SOURCE' { L _ ITsource_prag }
177 '{-# INLINE' { L _ ITinline_prag }
178 '{-# NOINLINE' { L _ ITnoinline_prag }
179 '{-# RULES' { L _ ITrules_prag }
180 '{-# CORE' { L _ ITcore_prag } -- hdaume: annotated core
181 '{-# SCC' { L _ ITscc_prag }
182 '{-# DEPRECATED' { L _ ITdeprecated_prag }
183 '{-# UNPACK' { L _ ITunpack_prag }
184 '#-}' { L _ ITclose_prag }
186 '..' { L _ ITdotdot } -- reserved symbols
188 '::' { L _ ITdcolon }
192 '<-' { L _ ITlarrow }
193 '->' { L _ ITrarrow }
196 '=>' { L _ ITdarrow }
200 '-<' { L _ ITlarrowtail } -- for arrow notation
201 '>-' { L _ ITrarrowtail } -- for arrow notation
202 '-<<' { L _ ITLarrowtail } -- for arrow notation
203 '>>-' { L _ ITRarrowtail } -- for arrow notation
206 '{' { L _ ITocurly } -- special symbols
208 '{|' { L _ ITocurlybar }
209 '|}' { L _ ITccurlybar }
210 vocurly { L _ ITvocurly } -- virtual open curly (from layout)
211 vccurly { L _ ITvccurly } -- virtual close curly (from layout)
214 '[:' { L _ ITopabrack }
215 ':]' { L _ ITcpabrack }
218 '(#' { L _ IToubxparen }
219 '#)' { L _ ITcubxparen }
220 '(|' { L _ IToparenbar }
221 '|)' { L _ ITcparenbar }
224 '`' { L _ ITbackquote }
226 VARID { L _ (ITvarid _) } -- identifiers
227 CONID { L _ (ITconid _) }
228 VARSYM { L _ (ITvarsym _) }
229 CONSYM { L _ (ITconsym _) }
230 QVARID { L _ (ITqvarid _) }
231 QCONID { L _ (ITqconid _) }
232 QVARSYM { L _ (ITqvarsym _) }
233 QCONSYM { L _ (ITqconsym _) }
235 IPDUPVARID { L _ (ITdupipvarid _) } -- GHC extension
236 IPSPLITVARID { L _ (ITsplitipvarid _) } -- GHC extension
238 CHAR { L _ (ITchar _) }
239 STRING { L _ (ITstring _) }
240 INTEGER { L _ (ITinteger _) }
241 RATIONAL { L _ (ITrational _) }
243 PRIMCHAR { L _ (ITprimchar _) }
244 PRIMSTRING { L _ (ITprimstring _) }
245 PRIMINTEGER { L _ (ITprimint _) }
246 PRIMFLOAT { L _ (ITprimfloat _) }
247 PRIMDOUBLE { L _ (ITprimdouble _) }
250 '[|' { L _ ITopenExpQuote }
251 '[p|' { L _ ITopenPatQuote }
252 '[t|' { L _ ITopenTypQuote }
253 '[d|' { L _ ITopenDecQuote }
254 '|]' { L _ ITcloseQuote }
255 TH_ID_SPLICE { L _ (ITidEscape _) } -- $x
256 '$(' { L _ ITparenEscape } -- $( exp )
257 TH_VAR_QUOTE { L _ ITvarQuote } -- 'x
258 TH_TY_QUOTE { L _ ITtyQuote } -- ''T
260 %monad { P } { >>= } { return }
261 %lexer { lexer } { L _ ITeof }
262 %name parseModule module
263 %name parseStmt maybe_stmt
264 %name parseIdentifier identifier
265 %name parseIface iface
266 %tokentype { Located Token }
269 -----------------------------------------------------------------------------
272 -- The place for module deprecation is really too restrictive, but if it
273 -- was allowed at its natural place just before 'module', we get an ugly
274 -- s/r conflict with the second alternative. Another solution would be the
275 -- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
276 -- either, and DEPRECATED is only expected to be used by people who really
277 -- know what they are doing. :-)
279 module :: { Located (HsModule RdrName) }
280 : 'module' modid maybemoddeprec maybeexports 'where' body
281 {% fileSrcSpan >>= \ loc ->
282 return (L loc (HsModule (Just (L (getLoc $2)
283 (mkHomeModule (unLoc $2))))
284 $4 (fst $6) (snd $6) $3)) }
285 | missing_module_keyword top close
286 {% fileSrcSpan >>= \ loc ->
287 return (L loc (HsModule Nothing Nothing
288 (fst $2) (snd $2) Nothing)) }
290 missing_module_keyword :: { () }
291 : {- empty -} {% pushCurrentContext }
293 maybemoddeprec :: { Maybe DeprecTxt }
294 : '{-# DEPRECATED' STRING '#-}' { Just (getSTRING $2) }
295 | {- empty -} { Nothing }
297 body :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
299 | vocurly top close { $2 }
301 top :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
302 : importdecls { (reverse $1,[]) }
303 | importdecls ';' cvtopdecls { (reverse $1,$3) }
304 | cvtopdecls { ([],$1) }
306 cvtopdecls :: { [LHsDecl RdrName] }
307 : topdecls { cvTopDecls $1 }
309 -----------------------------------------------------------------------------
310 -- Interfaces (.hi-boot files)
312 iface :: { ModIface }
313 : 'module' modid 'where' ifacebody { mkBootIface (unLoc $2) $4 }
315 ifacebody :: { [HsDecl RdrName] }
316 : '{' ifacedecls '}' { $2 }
317 | vocurly ifacedecls close { $2 }
319 ifacedecls :: { [HsDecl RdrName] }
320 : ifacedecl ';' ifacedecls { $1 : $3 }
321 | ';' ifacedecls { $2 }
325 ifacedecl :: { HsDecl RdrName }
328 | 'type' syn_hdr '=' ctype
329 { let (tc,tvs) = $2 in TyClD (TySynonym tc tvs $4) }
331 { TyClD (mkTyData DataType (unLoc $2) [] Nothing) }
333 { TyClD (mkTyData NewType (unLoc $2) [] Nothing) }
334 | 'class' tycl_hdr fds
335 { TyClD (mkClassDecl (unLoc $2) (unLoc $3) [] emptyBag) }
337 -----------------------------------------------------------------------------
340 maybeexports :: { Maybe [LIE RdrName] }
341 : '(' exportlist ')' { Just $2 }
342 | {- empty -} { Nothing }
344 exportlist :: { [LIE RdrName] }
345 : exportlist ',' export { $3 : $1 }
346 | exportlist ',' { $1 }
350 -- No longer allow things like [] and (,,,) to be exported
351 -- They are built in syntax, always available
352 export :: { LIE RdrName }
353 : qvar { L1 (IEVar (unLoc $1)) }
354 | oqtycon { L1 (IEThingAbs (unLoc $1)) }
355 | oqtycon '(' '..' ')' { LL (IEThingAll (unLoc $1)) }
356 | oqtycon '(' ')' { LL (IEThingWith (unLoc $1) []) }
357 | oqtycon '(' qcnames ')' { LL (IEThingWith (unLoc $1) (reverse $3)) }
358 | 'module' modid { LL (IEModuleContents (unLoc $2)) }
360 qcnames :: { [RdrName] }
361 : qcnames ',' qcname { unLoc $3 : $1 }
362 | qcname { [unLoc $1] }
364 qcname :: { Located RdrName } -- Variable or data constructor
368 -----------------------------------------------------------------------------
369 -- Import Declarations
371 -- import decls can be *empty*, or even just a string of semicolons
372 -- whereas topdecls must contain at least one topdecl.
374 importdecls :: { [LImportDecl RdrName] }
375 : importdecls ';' importdecl { $3 : $1 }
376 | importdecls ';' { $1 }
377 | importdecl { [ $1 ] }
380 importdecl :: { LImportDecl RdrName }
381 : 'import' maybe_src optqualified modid maybeas maybeimpspec
382 { L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }
384 maybe_src :: { IsBootInterface }
385 : '{-# SOURCE' '#-}' { True }
386 | {- empty -} { False }
388 optqualified :: { Bool }
389 : 'qualified' { True }
390 | {- empty -} { False }
392 maybeas :: { Located (Maybe ModuleName) }
393 : 'as' modid { LL (Just (unLoc $2)) }
394 | {- empty -} { noLoc Nothing }
396 maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
397 : impspec { L1 (Just (unLoc $1)) }
398 | {- empty -} { noLoc Nothing }
400 impspec :: { Located (Bool, [LIE RdrName]) }
401 : '(' exportlist ')' { LL (False, reverse $2) }
402 | 'hiding' '(' exportlist ')' { LL (True, reverse $3) }
404 -----------------------------------------------------------------------------
405 -- Fixity Declarations
409 | INTEGER {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
411 infix :: { Located FixityDirection }
412 : 'infix' { L1 InfixN }
413 | 'infixl' { L1 InfixL }
414 | 'infixr' { L1 InfixR }
416 ops :: { Located [Located RdrName] }
417 : ops ',' op { LL ($3 : unLoc $1) }
420 -----------------------------------------------------------------------------
421 -- Top-Level Declarations
423 topdecls :: { OrdList (LHsDecl RdrName) } -- Reversed
424 : topdecls ';' topdecl { $1 `appOL` $3 }
425 | topdecls ';' { $1 }
428 topdecl :: { OrdList (LHsDecl RdrName) }
429 : tycl_decl { unitOL (L1 (TyClD (unLoc $1))) }
430 | 'instance' inst_type where
431 { let (binds,sigs) = cvBindsAndSigs (unLoc $3)
432 in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
433 | 'default' '(' comma_types0 ')' { unitOL (LL $ DefD (DefaultDecl $3)) }
434 | 'foreign' fdecl { unitOL (LL (unLoc $2)) }
435 | '{-# DEPRECATED' deprecations '#-}' { $2 }
436 | '{-# RULES' rules '#-}' { $2 }
437 | '$(' exp ')' { unitOL (LL $ SpliceD (SpliceDecl $2)) }
440 tycl_decl :: { LTyClDecl RdrName }
441 : 'type' syn_hdr '=' ctype
442 -- Note ctype, not sigtype.
443 -- We allow an explicit for-all but we don't insert one
444 -- in type Foo a = (b,b)
445 -- Instead we just say b is out of scope
446 { LL $ let (tc,tvs) = $2 in TySynonym tc tvs $4 }
448 | 'data' tycl_hdr constrs deriving
449 { L (comb4 $1 $2 $3 $4)
450 (mkTyData DataType (unLoc $2) (reverse (unLoc $3)) (unLoc $4)) }
452 | 'newtype' tycl_hdr '=' newconstr deriving
454 (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
456 | 'class' tycl_hdr fds where
458 (binds,sigs) = cvBindsAndSigs (unLoc $4)
460 L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs
463 syn_hdr :: { (Located RdrName, [LHsTyVarBndr RdrName]) }
464 -- We don't retain the syntax of an infix
465 -- type synonym declaration. Oh well.
466 : tycon tv_bndrs { ($1, $2) }
467 | tv_bndr tyconop tv_bndr { ($2, [$1,$3]) }
469 -- tycl_hdr parses the header of a type or class decl,
470 -- which takes the form
473 -- (Eq a, Ord b) => T a b
474 -- Rather a lot of inlining here, else we get reduce/reduce errors
475 tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
476 : context '=>' type {% checkTyClHdr $1 $3 >>= return.LL }
477 | type {% checkTyClHdr (noLoc []) $1 >>= return.L1 }
479 -----------------------------------------------------------------------------
480 -- Nested declarations
482 decls :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
483 : decls ';' decl { LL (unLoc $1 `appOL` unLoc $3) }
484 | decls ';' { LL (unLoc $1) }
485 | decl { L1 (unLoc $1) }
486 | {- empty -} { noLoc nilOL }
489 decllist :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
490 : '{' decls '}' { LL (unLoc $2) }
491 | vocurly decls close { $2 }
493 where :: { Located (OrdList (LHsDecl RdrName)) } -- Reversed
494 -- No implicit parameters
495 : 'where' decllist { LL (unLoc $2) }
496 | {- empty -} { noLoc nilOL }
498 binds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
499 : decllist { L1 [cvBindGroup (unLoc $1)] }
500 | '{' dbinds '}' { LL [HsIPBinds (unLoc $2)] }
501 | vocurly dbinds close { L (getLoc $2) [HsIPBinds (unLoc $2)] }
503 wherebinds :: { Located [HsBindGroup RdrName] } -- May have implicit parameters
504 : 'where' binds { LL (unLoc $2) }
505 | {- empty -} { noLoc [] }
508 -----------------------------------------------------------------------------
509 -- Transformation Rules
511 rules :: { OrdList (LHsDecl RdrName) } -- Reversed
512 : rules ';' rule { $1 `snocOL` $3 }
515 | {- empty -} { nilOL }
517 rule :: { LHsDecl RdrName }
518 : STRING activation rule_forall infixexp '=' exp
519 { LL $ RuleD (HsRule (getSTRING $1) $2 $3 $4 $6) }
521 activation :: { Activation } -- Omitted means AlwaysActive
522 : {- empty -} { AlwaysActive }
523 | explicit_activation { $1 }
525 inverse_activation :: { Activation } -- Omitted means NeverActive
526 : {- empty -} { NeverActive }
527 | explicit_activation { $1 }
529 explicit_activation :: { Activation } -- In brackets
530 : '[' INTEGER ']' { ActiveAfter (fromInteger (getINTEGER $2)) }
531 | '[' '~' INTEGER ']' { ActiveBefore (fromInteger (getINTEGER $3)) }
533 rule_forall :: { [RuleBndr RdrName] }
534 : 'forall' rule_var_list '.' { $2 }
537 rule_var_list :: { [RuleBndr RdrName] }
539 | rule_var rule_var_list { $1 : $2 }
541 rule_var :: { RuleBndr RdrName }
542 : varid { RuleBndr $1 }
543 | '(' varid '::' ctype ')' { RuleBndrSig $2 $4 }
545 -----------------------------------------------------------------------------
546 -- Deprecations (c.f. rules)
548 deprecations :: { OrdList (LHsDecl RdrName) } -- Reversed
549 : deprecations ';' deprecation { $1 `appOL` $3 }
550 | deprecations ';' { $1 }
552 | {- empty -} { nilOL }
554 -- SUP: TEMPORARY HACK, not checking for `module Foo'
555 deprecation :: { OrdList (LHsDecl RdrName) }
557 { toOL [ LL $ DeprecD (Deprecation n (getSTRING $2))
561 -----------------------------------------------------------------------------
562 -- Foreign import and export declarations
564 -- for the time being, the following accepts foreign declarations conforming
565 -- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
567 -- * a flag indicates whether pre-standard declarations have been used and
568 -- triggers a deprecation warning further down the road
570 -- NB: The first two rules could be combined into one by replacing `safety1'
571 -- with `safety'. However, the combined rule conflicts with the
574 fdecl :: { LHsDecl RdrName }
575 fdecl : 'import' callconv safety1 fspec
576 {% mkImport $2 $3 (unLoc $4) >>= return.LL }
577 | 'import' callconv fspec
578 {% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
580 | 'export' callconv fspec
581 {% mkExport $2 (unLoc $3) >>= return.LL }
582 -- the following syntax is DEPRECATED
583 | fdecl1DEPRECATED { L1 (ForD (unLoc $1)) }
584 | fdecl2DEPRECATED { L1 (unLoc $1) }
586 fdecl1DEPRECATED :: { LForeignDecl RdrName }
588 ----------- DEPRECATED label decls ------------
589 : 'label' ext_name varid '::' sigtype
590 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
591 (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }
593 ----------- DEPRECATED ccall/stdcall decls ------------
595 -- NB: This business with the case expression below may seem overly
596 -- complicated, but it is necessary to avoid some conflicts.
598 -- DEPRECATED variant #1: lack of a calling convention specification
600 | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
602 target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
604 LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
605 (CFunction target)) True }
607 -- DEPRECATED variant #2: external name consists of two separate strings
608 -- (module name and function name) (import)
609 | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
611 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
612 CCall cconv -> return $
614 imp = CFunction (StaticTarget (getSTRING $4))
616 LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }
618 -- DEPRECATED variant #3: `unsafe' after entity
619 | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
621 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
622 CCall cconv -> return $
624 imp = CFunction (StaticTarget (getSTRING $3))
626 LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }
628 -- DEPRECATED variant #4: use of the special identifier `dynamic' without
629 -- an explicit calling convention (import)
630 | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
631 { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS
632 (CFunction DynamicTarget)) True }
634 -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
635 | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
637 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
638 CCall cconv -> return $
639 LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS
640 (CFunction DynamicTarget)) True }
642 -- DEPRECATED variant #6: lack of a calling convention specification
644 | 'export' {-no callconv-} ext_name varid '::' sigtype
645 { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
646 defaultCCallConv)) True }
648 -- DEPRECATED variant #7: external name consists of two separate strings
649 -- (module name and function name) (export)
650 | 'export' callconv STRING STRING varid '::' sigtype
652 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
653 CCall cconv -> return $
654 LL $ ForeignExport $5 $7
655 (CExport (CExportStatic (getSTRING $4) cconv)) True }
657 -- DEPRECATED variant #8: use of the special identifier `dynamic' without
658 -- an explicit calling convention (export)
659 | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
660 { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS
663 -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
664 | 'export' callconv 'dynamic' varid '::' sigtype
666 DNCall -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
667 CCall cconv -> return $
668 LL $ ForeignImport $4 $6
669 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }
671 ----------- DEPRECATED .NET decls ------------
672 -- NB: removed the .NET call declaration, as it is entirely subsumed
673 -- by the new standard FFI declarations
675 fdecl2DEPRECATED :: { LHsDecl RdrName }
677 : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
678 -- left this one unchanged for the moment as type imports are not
679 -- covered currently by the FFI standard -=chak
682 callconv :: { CallConv }
683 : 'stdcall' { CCall StdCallConv }
684 | 'ccall' { CCall CCallConv }
685 | 'dotnet' { DNCall }
688 : 'unsafe' { PlayRisky }
689 | 'safe' { PlaySafe False }
690 | 'threadsafe' { PlaySafe True }
691 | {- empty -} { PlaySafe False }
693 safety1 :: { Safety }
694 : 'unsafe' { PlayRisky }
695 | 'safe' { PlaySafe False }
696 | 'threadsafe' { PlaySafe True }
697 -- only needed to avoid conflicts with the DEPRECATED rules
699 fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
700 : STRING var '::' sigtype { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
701 | var '::' sigtype { LL (noLoc nilFS, $1, $3) }
702 -- if the entity string is missing, it defaults to the empty string;
703 -- the meaning of an empty entity string depends on the calling
707 ext_name :: { Maybe CLabelString }
708 : STRING { Just (getSTRING $1) }
709 | STRING STRING { Just (getSTRING $2) } -- Ignore "module name" for now
710 | {- empty -} { Nothing }
713 -----------------------------------------------------------------------------
716 opt_sig :: { Maybe (LHsType RdrName) }
717 : {- empty -} { Nothing }
718 | '::' sigtype { Just $2 }
720 opt_asig :: { Maybe (LHsType RdrName) }
721 : {- empty -} { Nothing }
722 | '::' atype { Just $2 }
724 sigtypes :: { [LHsType RdrName] }
726 | sigtypes ',' sigtype { $3 : $1 }
728 sigtype :: { LHsType RdrName }
729 : ctype { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
730 -- Wrap an Implicit forall if there isn't one there already
732 sig_vars :: { Located [Located RdrName] }
733 : sig_vars ',' var { LL ($3 : unLoc $1) }
736 -----------------------------------------------------------------------------
739 -- A ctype is a for-all type
740 ctype :: { LHsType RdrName }
741 : 'forall' tv_bndrs '.' ctype { LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
742 | context '=>' type { LL $ mkImplicitHsForAllTy $1 $3 }
743 -- A type of form (context => type) is an *implicit* HsForAllTy
746 -- We parse a context as a btype so that we don't get reduce/reduce
747 -- errors in ctype. The basic problem is that
749 -- looks so much like a tuple type. We can't tell until we find the =>
750 context :: { LHsContext RdrName }
751 : btype {% checkContext $1 }
753 type :: { LHsType RdrName }
754 : ipvar '::' gentype { LL (HsPredTy (LL $ HsIParam (unLoc $1) $3)) }
757 gentype :: { LHsType RdrName }
759 | btype qtyconop gentype { LL $ HsOpTy $1 $2 $3 }
760 | btype '`' tyvar '`' gentype { LL $ HsOpTy $1 $3 $5 }
761 | btype '->' gentype { LL $ HsFunTy $1 $3 }
763 btype :: { LHsType RdrName }
764 : btype atype { LL $ HsAppTy $1 $2 }
767 atype :: { LHsType RdrName }
768 : gtycon { L1 (HsTyVar (unLoc $1)) }
769 | tyvar { L1 (HsTyVar (unLoc $1)) }
770 | '(' type ',' comma_types1 ')' { LL $ HsTupleTy Boxed ($2:$4) }
771 | '(#' comma_types1 '#)' { LL $ HsTupleTy Unboxed $2 }
772 | '[' type ']' { LL $ HsListTy $2 }
773 | '[:' type ':]' { LL $ HsPArrTy $2 }
774 | '(' ctype ')' { LL $ HsParTy $2 }
775 | '(' ctype '::' kind ')' { LL $ HsKindSig $2 $4 }
777 | INTEGER { L1 (HsNumTy (getINTEGER $1)) }
779 -- An inst_type is what occurs in the head of an instance decl
780 -- e.g. (Foo a, Gaz b) => Wibble a b
781 -- It's kept as a single type, with a MonoDictTy at the right
782 -- hand corner, for convenience.
783 inst_type :: { LHsType RdrName }
784 : ctype {% checkInstType $1 }
786 comma_types0 :: { [LHsType RdrName] }
787 : comma_types1 { $1 }
790 comma_types1 :: { [LHsType RdrName] }
792 | type ',' comma_types1 { $1 : $3 }
794 tv_bndrs :: { [LHsTyVarBndr RdrName] }
795 : tv_bndr tv_bndrs { $1 : $2 }
798 tv_bndr :: { LHsTyVarBndr RdrName }
799 : tyvar { L1 (UserTyVar (unLoc $1)) }
800 | '(' tyvar '::' kind ')' { LL (KindedTyVar (unLoc $2) $4) }
802 fds :: { Located [Located ([RdrName], [RdrName])] }
803 : {- empty -} { noLoc [] }
804 | '|' fds1 { LL (reverse (unLoc $2)) }
806 fds1 :: { Located [Located ([RdrName], [RdrName])] }
807 : fds1 ',' fd { LL ($3 : unLoc $1) }
810 fd :: { Located ([RdrName], [RdrName]) }
811 : varids0 '->' varids0 { L (comb3 $1 $2 $3)
812 (reverse (unLoc $1), reverse (unLoc $3)) }
814 varids0 :: { Located [RdrName] }
815 : {- empty -} { noLoc [] }
816 | varids0 tyvar { LL (unLoc $2 : unLoc $1) }
818 -----------------------------------------------------------------------------
823 | akind '->' kind { mkArrowKind $1 $3 }
826 : '*' { liftedTypeKind }
827 | '(' kind ')' { $2 }
830 -----------------------------------------------------------------------------
831 -- Datatype declarations
833 newconstr :: { LConDecl RdrName }
834 : conid atype { LL $ ConDecl $1 [] (noLoc [])
835 (PrefixCon [(unbangedType $2)]) }
836 | conid '{' var '::' ctype '}'
837 { LL $ ConDecl $1 [] (noLoc [])
838 (RecCon [($3, (unbangedType $5))]) }
840 constrs :: { Located [LConDecl RdrName] }
841 : {- empty; a GHC extension -} { noLoc [] }
842 | '=' constrs1 { LL (unLoc $2) }
844 constrs1 :: { Located [LConDecl RdrName] }
845 : constrs1 '|' constr { LL ($3 : unLoc $1) }
848 constr :: { LConDecl RdrName }
849 : forall context '=>' constr_stuff
850 { let (con,details) = unLoc $4 in
851 LL (ConDecl con (unLoc $1) $2 details) }
852 | forall constr_stuff
853 { let (con,details) = unLoc $2 in
854 LL (ConDecl con (unLoc $1) (noLoc []) details) }
856 forall :: { Located [LHsTyVarBndr RdrName] }
857 : 'forall' tv_bndrs '.' { LL $2 }
858 | {- empty -} { noLoc [] }
860 constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
861 : btype {% mkPrefixCon $1 [] >>= return.LL }
862 | btype bang_atype satypes {% do { r <- mkPrefixCon $1 ($2 : unLoc $3);
863 return (L (comb3 $1 $2 $3) r) } }
864 | oqtycon '{' '}' {% mkRecCon $1 [] >>= return.LL }
865 | oqtycon '{' fielddecls '}' {% mkRecCon $1 $3 >>= return.LL }
866 | sbtype conop sbtype { LL ($2, InfixCon $1 $3) }
868 bang_atype :: { LBangType RdrName }
869 : strict_mark atype { LL (BangType (unLoc $1) $2) }
871 satypes :: { Located [LBangType RdrName] }
872 : atype satypes { LL (unbangedType $1 : unLoc $2) }
873 | bang_atype satypes { LL ($1 : unLoc $2) }
874 | {- empty -} { noLoc [] }
876 sbtype :: { LBangType RdrName }
877 : btype { unbangedType $1 }
878 | strict_mark atype { LL (BangType (unLoc $1) $2) }
880 fielddecls :: { [([Located RdrName], LBangType RdrName)] }
881 : fielddecl ',' fielddecls { unLoc $1 : $3 }
882 | fielddecl { [unLoc $1] }
884 fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
885 : sig_vars '::' stype { LL (reverse (unLoc $1), $3) }
887 stype :: { LBangType RdrName }
888 : ctype { unbangedType $1 }
889 | strict_mark atype { LL (BangType (unLoc $1) $2) }
891 strict_mark :: { Located HsBang }
892 : '!' { L1 HsStrict }
893 | '{-# UNPACK' '#-}' '!' { LL HsUnbox }
895 deriving :: { Located (Maybe (LHsContext RdrName)) }
896 : {- empty -} { noLoc Nothing }
897 | 'deriving' context { LL (Just $2) }
898 -- Glasgow extension: allow partial
899 -- applications in derivings
901 -----------------------------------------------------------------------------
904 {- There's an awkward overlap with a type signature. Consider
905 f :: Int -> Int = ...rhs...
906 Then we can't tell whether it's a type signature or a value
907 definition with a result signature until we see the '='.
908 So we have to inline enough to postpone reductions until we know.
912 ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
913 instead of qvar, we get another shift/reduce-conflict. Consider the
916 { (^^) :: Int->Int ; } Type signature; only var allowed
918 { (^^) :: Int->Int = ... ; } Value defn with result signature;
919 qvar allowed (because of instance decls)
921 We can't tell whether to reduce var to qvar until after we've read the signatures.
924 decl :: { Located (OrdList (LHsDecl RdrName)) }
926 | infixexp opt_sig rhs {% do { r <- checkValDef $1 $2 (unLoc $3);
927 return (LL $ unitOL (LL $ ValD r)) } }
929 rhs :: { Located (GRHSs RdrName) }
930 : '=' exp wherebinds { L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) placeHolderType }
931 | gdrhs wherebinds { LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) placeHolderType }
933 gdrhs :: { Located [LGRHS RdrName] }
934 : gdrhs gdrh { LL ($2 : unLoc $1) }
937 gdrh :: { LGRHS RdrName }
938 : '|' quals '=' exp { LL $ GRHS (reverse (L (getLoc $4) (ResultStmt $4) :
941 sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
942 : infixexp '::' sigtype
943 {% do s <- checkValSig $1 $3;
944 return (LL $ unitOL (LL $ SigD s)) }
945 -- See the above notes for why we need infixexp here
946 | var ',' sig_vars '::' sigtype
947 { LL $ toOL [ LL $ SigD (Sig n $5) | n <- $1 : unLoc $3 ] }
948 | infix prec ops { LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
950 | '{-# INLINE' activation qvar '#-}'
951 { LL $ unitOL (LL $ SigD (InlineSig True $3 $2)) }
952 | '{-# NOINLINE' inverse_activation qvar '#-}'
953 { LL $ unitOL (LL $ SigD (InlineSig False $3 $2)) }
954 | '{-# SPECIALISE' qvar '::' sigtypes '#-}'
955 { LL $ toOL [ LL $ SigD (SpecSig $2 t)
957 | '{-# SPECIALISE' 'instance' inst_type '#-}'
958 { LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
960 -----------------------------------------------------------------------------
963 exp :: { LHsExpr RdrName }
964 : infixexp '::' sigtype { LL $ ExprWithTySig $1 $3 }
965 | fexp '-<' exp { LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
966 | fexp '>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
967 | fexp '-<<' exp { LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
968 | fexp '>>-' exp { LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
971 infixexp :: { LHsExpr RdrName }
973 | infixexp qop exp10 { LL (OpApp $1 $2 (panic "fixity") $3) }
975 exp10 :: { LHsExpr RdrName }
976 : '\\' aexp aexps opt_asig '->' exp
977 {% checkPatterns ($2 : reverse $3) >>= \ ps ->
978 return (LL $ HsLam (LL $ Match ps $4
979 (GRHSs (unguardedRHS $6) []
981 | 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
982 | 'if' exp 'then' exp 'else' exp { LL $ HsIf $2 $4 $6 }
983 | 'case' exp 'of' altslist { LL $ HsCase $2 (unLoc $4) }
984 | '-' fexp { LL $ mkHsNegApp $2 }
986 | 'do' stmtlist {% let loc = comb2 $1 $2 in
987 checkDo loc (unLoc $2) >>= \ stmts ->
988 return (L loc (mkHsDo DoExpr stmts)) }
989 | 'mdo' stmtlist {% let loc = comb2 $1 $2 in
990 checkMDo loc (unLoc $2) >>= \ stmts ->
991 return (L loc (mkHsDo MDoExpr stmts)) }
993 | scc_annot exp { LL $ if opt_SccProfilingOn
994 then HsSCC (unLoc $1) $2
997 | 'proc' aexp '->' exp
998 {% checkPattern $2 >>= \ p ->
999 return (LL $ HsProc p (LL $ HsCmdTop $4 []
1000 placeHolderType undefined)) }
1001 -- TODO: is LL right here?
1003 | '{-# CORE' STRING '#-}' exp { LL $ HsCoreAnn (getSTRING $2) $4 }
1004 -- hdaume: core annotation
1007 scc_annot :: { Located FastString }
1008 : '_scc_' STRING { LL $ getSTRING $2 }
1009 | '{-# SCC' STRING '#-}' { LL $ getSTRING $2 }
1011 fexp :: { LHsExpr RdrName }
1012 : fexp aexp { LL $ HsApp $1 $2 }
1015 aexps :: { [LHsExpr RdrName] }
1016 : aexps aexp { $2 : $1 }
1017 | {- empty -} { [] }
1019 aexp :: { LHsExpr RdrName }
1020 : qvar '@' aexp { LL $ EAsPat $1 $3 }
1021 | '~' aexp { LL $ ELazyPat $2 }
1024 aexp1 :: { LHsExpr RdrName }
1025 : aexp1 '{' fbinds '}' {% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4)
1030 -- Here was the syntax for type applications that I was planning
1031 -- but there are difficulties (e.g. what order for type args)
1032 -- so it's not enabled yet.
1033 -- But this case *is* used for the left hand side of a generic definition,
1034 -- which is parsed as an expression before being munged into a pattern
1035 | qcname '{|' gentype '|}' { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
1036 (sL (getLoc $3) (HsType $3)) }
1038 aexp2 :: { LHsExpr RdrName }
1039 : ipvar { L1 (HsIPVar $! unLoc $1) }
1040 | qcname { L1 (HsVar $! unLoc $1) }
1041 | literal { L1 (HsLit $! unLoc $1) }
1042 | INTEGER { L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
1043 | RATIONAL { L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
1044 | '(' exp ')' { LL (HsPar $2) }
1045 | '(' exp ',' texps ')' { LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1046 | '(#' texps '#)' { LL $ ExplicitTuple (reverse $2) Unboxed }
1047 | '[' list ']' { LL (unLoc $2) }
1048 | '[:' parr ':]' { LL (unLoc $2) }
1049 | '(' infixexp qop ')' { LL $ SectionL $2 $3 }
1050 | '(' qopm infixexp ')' { LL $ SectionR $2 $3 }
1051 | '_' { L1 EWildPat }
1053 -- MetaHaskell Extension
1054 | TH_ID_SPLICE { L1 $ mkHsSplice
1055 (L1 $ HsVar (mkUnqual varName
1056 (getTH_ID_SPLICE $1))) } -- $x
1057 | '$(' exp ')' { LL $ mkHsSplice $2 } -- $( exp )
1058 | TH_VAR_QUOTE qvar { LL $ HsBracket (VarBr (unLoc $2)) }
1059 | TH_VAR_QUOTE qcon { LL $ HsBracket (VarBr (unLoc $2)) }
1060 | TH_TY_QUOTE tyvar { LL $ HsBracket (VarBr (unLoc $2)) }
1061 | TH_TY_QUOTE gtycon { LL $ HsBracket (VarBr (unLoc $2)) }
1062 | '[|' exp '|]' { LL $ HsBracket (ExpBr $2) }
1063 | '[t|' ctype '|]' { LL $ HsBracket (TypBr $2) }
1064 | '[p|' infixexp '|]' {% checkPattern $2 >>= \p ->
1065 return (LL $ HsBracket (PatBr p)) }
1066 | '[d|' cvtopbody '|]' { LL $ HsBracket (DecBr (mkGroup $2)) }
1068 -- arrow notation extension
1069 | '(|' aexp2 cmdargs '|)' { LL $ HsArrForm $2 Nothing (reverse $3) }
1071 cmdargs :: { [LHsCmdTop RdrName] }
1072 : cmdargs acmd { $2 : $1 }
1073 | {- empty -} { [] }
1075 acmd :: { LHsCmdTop RdrName }
1076 : aexp2 { L1 $ HsCmdTop $1 [] placeHolderType undefined }
1078 cvtopbody :: { [LHsDecl RdrName] }
1079 : '{' cvtopdecls '}' { $2 }
1080 | vocurly cvtopdecls close { $2 }
1082 texps :: { [LHsExpr RdrName] }
1083 : texps ',' exp { $3 : $1 }
1087 -----------------------------------------------------------------------------
1090 -- The rules below are little bit contorted to keep lexps left-recursive while
1091 -- avoiding another shift/reduce-conflict.
1093 list :: { LHsExpr RdrName }
1094 : exp { L1 $ ExplicitList placeHolderType [$1] }
1095 | lexps { L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
1096 | exp '..' { LL $ ArithSeqIn (From $1) }
1097 | exp ',' exp '..' { LL $ ArithSeqIn (FromThen $1 $3) }
1098 | exp '..' exp { LL $ ArithSeqIn (FromTo $1 $3) }
1099 | exp ',' exp '..' exp { LL $ ArithSeqIn (FromThenTo $1 $3 $5) }
1100 | exp pquals { LL $ mkHsDo ListComp
1101 (reverse (L (getLoc $1) (ResultStmt $1) :
1104 lexps :: { Located [LHsExpr RdrName] }
1105 : lexps ',' exp { LL ($3 : unLoc $1) }
1106 | exp ',' exp { LL [$3,$1] }
1108 -----------------------------------------------------------------------------
1109 -- List Comprehensions
1111 pquals :: { Located [LStmt RdrName] } -- Either a singleton ParStmt,
1112 -- or a reversed list of Stmts
1113 : pquals1 { case unLoc $1 of
1115 qss -> L1 [L1 (ParStmt stmtss)]
1117 stmtss = [ (reverse qs, undefined)
1121 pquals1 :: { Located [[LStmt RdrName]] }
1122 : pquals1 '|' quals { LL (unLoc $3 : unLoc $1) }
1123 | '|' quals { L (getLoc $2) [unLoc $2] }
1125 quals :: { Located [LStmt RdrName] }
1126 : quals ',' qual { LL ($3 : unLoc $1) }
1129 -----------------------------------------------------------------------------
1130 -- Parallel array expressions
1132 -- The rules below are little bit contorted; see the list case for details.
1133 -- Note that, in contrast to lists, we only have finite arithmetic sequences.
1134 -- Moreover, we allow explicit arrays with no element (represented by the nil
1135 -- constructor in the list case).
1137 parr :: { LHsExpr RdrName }
1138 : { noLoc (ExplicitPArr placeHolderType []) }
1139 | exp { L1 $ ExplicitPArr placeHolderType [$1] }
1140 | lexps { L1 $ ExplicitPArr placeHolderType
1141 (reverse (unLoc $1)) }
1142 | exp '..' exp { LL $ PArrSeqIn (FromTo $1 $3) }
1143 | exp ',' exp '..' exp { LL $ PArrSeqIn (FromThenTo $1 $3 $5) }
1144 | exp pquals { LL $ mkHsDo PArrComp
1145 (reverse (L (getLoc $1) (ResultStmt $1) :
1149 -- We are reusing `lexps' and `pquals' from the list case.
1151 -----------------------------------------------------------------------------
1152 -- Case alternatives
1154 altslist :: { Located [LMatch RdrName] }
1155 : '{' alts '}' { LL (reverse (unLoc $2)) }
1156 | vocurly alts close { L (getLoc $2) (reverse (unLoc $2)) }
1158 alts :: { Located [LMatch RdrName] }
1159 : alts1 { L1 (unLoc $1) }
1160 | ';' alts { LL (unLoc $2) }
1162 alts1 :: { Located [LMatch RdrName] }
1163 : alts1 ';' alt { LL ($3 : unLoc $1) }
1164 | alts1 ';' { LL (unLoc $1) }
1167 alt :: { LMatch RdrName }
1168 : infixexp opt_sig alt_rhs {% checkPattern $1 >>= \p ->
1169 return (LL (Match [p] $2 (unLoc $3))) }
1171 alt_rhs :: { Located (GRHSs RdrName) }
1172 : ralt wherebinds { LL (GRHSs (unLoc $1) (unLoc $2)
1175 ralt :: { Located [LGRHS RdrName] }
1176 : '->' exp { LL (unguardedRHS $2) }
1177 | gdpats { L1 (reverse (unLoc $1)) }
1179 gdpats :: { Located [LGRHS RdrName] }
1180 : gdpats gdpat { LL ($2 : unLoc $1) }
1183 gdpat :: { LGRHS RdrName }
1184 : '|' quals '->' exp { let r = L (getLoc $4) (ResultStmt $4)
1185 in LL $ GRHS (reverse (r : unLoc $2)) }
1187 -----------------------------------------------------------------------------
1188 -- Statement sequences
1190 stmtlist :: { Located [LStmt RdrName] }
1191 : '{' stmts '}' { LL (unLoc $2) }
1192 | vocurly stmts close { $2 }
1194 -- do { ;; s ; s ; ; s ;; }
1195 -- The last Stmt should be a ResultStmt, but that's hard to enforce
1196 -- here, because we need too much lookahead if we see do { e ; }
1197 -- So we use ExprStmts throughout, and switch the last one over
1198 -- in ParseUtils.checkDo instead
1199 stmts :: { Located [LStmt RdrName] }
1200 : stmt stmts_help { LL ($1 : unLoc $2) }
1201 | ';' stmts { LL (unLoc $2) }
1202 | {- empty -} { noLoc [] }
1204 stmts_help :: { Located [LStmt RdrName] } -- might be empty
1205 : ';' stmts { LL (unLoc $2) }
1206 | {- empty -} { noLoc [] }
1208 -- For typing stmts at the GHCi prompt, where
1209 -- the input may consist of just comments.
1210 maybe_stmt :: { Maybe (LStmt RdrName) }
1212 | {- nothing -} { Nothing }
1214 stmt :: { LStmt RdrName }
1216 | infixexp '->' exp {% checkPattern $3 >>= \p ->
1217 return (LL $ BindStmt p $1) }
1218 | 'rec' stmtlist { LL $ RecStmt (unLoc $2) undefined undefined undefined }
1220 qual :: { LStmt RdrName }
1221 : infixexp '<-' exp {% checkPattern $1 >>= \p ->
1222 return (LL $ BindStmt p $3) }
1223 | exp { L1 $ ExprStmt $1 placeHolderType }
1224 | 'let' binds { LL $ LetStmt (unLoc $2) }
1226 -----------------------------------------------------------------------------
1227 -- Record Field Update/Construction
1229 fbinds :: { HsRecordBinds RdrName }
1231 | {- empty -} { [] }
1233 fbinds1 :: { HsRecordBinds RdrName }
1234 : fbinds1 ',' fbind { $3 : $1 }
1237 fbind :: { (Located RdrName, LHsExpr RdrName) }
1238 : qvar '=' exp { ($1,$3) }
1240 -----------------------------------------------------------------------------
1241 -- Implicit Parameter Bindings
1243 dbinds :: { Located [LIPBind RdrName] }
1244 : dbinds ';' dbind { LL ($3 : unLoc $1) }
1245 | dbinds ';' { LL (unLoc $1) }
1247 -- | {- empty -} { [] }
1249 dbind :: { LIPBind RdrName }
1250 dbind : ipvar '=' exp { LL (IPBind (unLoc $1) $3) }
1252 -----------------------------------------------------------------------------
1253 -- Variables, Constructors and Operators.
1255 identifier :: { Located RdrName }
1261 depreclist :: { Located [RdrName] }
1262 depreclist : deprec_var { L1 [unLoc $1] }
1263 | deprec_var ',' depreclist { LL (unLoc $1 : unLoc $3) }
1265 deprec_var :: { Located RdrName }
1266 deprec_var : var { $1 }
1269 gcon :: { Located RdrName } -- Data constructor namespace
1270 : sysdcon { L1 $ nameRdrName (dataConName (unLoc $1)) }
1272 -- the case of '[:' ':]' is part of the production `parr'
1274 sysdcon :: { Located DataCon } -- Wired in data constructors
1275 : '(' ')' { LL unitDataCon }
1276 | '(' commas ')' { LL $ tupleCon Boxed $2 }
1277 | '[' ']' { LL nilDataCon }
1279 var :: { Located RdrName }
1281 | '(' varsym ')' { LL (unLoc $2) }
1283 qvar :: { Located RdrName }
1285 | '(' varsym ')' { LL (unLoc $2) }
1286 | '(' qvarsym1 ')' { LL (unLoc $2) }
1287 -- We've inlined qvarsym here so that the decision about
1288 -- whether it's a qvar or a var can be postponed until
1289 -- *after* we see the close paren.
1291 ipvar :: { Located (IPName RdrName) }
1292 : IPDUPVARID { L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
1293 | IPSPLITVARID { L1 (Linear (mkUnqual varName (getIPSPLITVARID $1))) }
1295 qcon :: { Located RdrName }
1297 | '(' qconsym ')' { LL (unLoc $2) }
1299 varop :: { Located RdrName }
1301 | '`' varid '`' { LL (unLoc $2) }
1303 qvarop :: { Located RdrName }
1305 | '`' qvarid '`' { LL (unLoc $2) }
1307 qvaropm :: { Located RdrName }
1308 : qvarsym_no_minus { $1 }
1309 | '`' qvarid '`' { LL (unLoc $2) }
1311 conop :: { Located RdrName }
1313 | '`' conid '`' { LL (unLoc $2) }
1315 qconop :: { Located RdrName }
1317 | '`' qconid '`' { LL (unLoc $2) }
1319 -----------------------------------------------------------------------------
1320 -- Type constructors
1322 gtycon :: { Located RdrName } -- A "general" qualified tycon
1324 | '(' ')' { LL $ getRdrName unitTyCon }
1325 | '(' commas ')' { LL $ getRdrName (tupleTyCon Boxed $2) }
1326 | '(' '->' ')' { LL $ getRdrName funTyCon }
1327 | '[' ']' { LL $ listTyCon_RDR }
1328 | '[:' ':]' { LL $ parrTyCon_RDR }
1330 oqtycon :: { Located RdrName } -- An "ordinary" qualified tycon
1332 | '(' qtyconsym ')' { LL (unLoc $2) }
1334 qtyconop :: { Located RdrName } -- Qualified or unqualified
1336 | '`' qtycon '`' { LL (unLoc $2) }
1338 tyconop :: { Located RdrName } -- Unqualified
1340 | '`' tycon '`' { LL (unLoc $2) }
1342 qtycon :: { Located RdrName } -- Qualified or unqualified
1343 : QCONID { L1 $! mkQual tcClsName (getQCONID $1) }
1346 tycon :: { Located RdrName } -- Unqualified
1347 : CONID { L1 $! mkUnqual tcClsName (getCONID $1) }
1349 qtyconsym :: { Located RdrName }
1350 : QCONSYM { L1 $! mkQual tcClsName (getQCONSYM $1) }
1353 tyconsym :: { Located RdrName }
1354 : CONSYM { L1 $! mkUnqual tcClsName (getCONSYM $1) }
1356 -----------------------------------------------------------------------------
1359 op :: { Located RdrName } -- used in infix decls
1363 qop :: { LHsExpr RdrName } -- used in sections
1364 : qvarop { L1 $ HsVar (unLoc $1) }
1365 | qconop { L1 $ HsVar (unLoc $1) }
1367 qopm :: { LHsExpr RdrName } -- used in sections
1368 : qvaropm { L1 $ HsVar (unLoc $1) }
1369 | qconop { L1 $ HsVar (unLoc $1) }
1371 -----------------------------------------------------------------------------
1374 qvarid :: { Located RdrName }
1376 | QVARID { L1 $ mkQual varName (getQVARID $1) }
1378 varid :: { Located RdrName }
1379 : varid_no_unsafe { $1 }
1380 | 'unsafe' { L1 $! mkUnqual varName FSLIT("unsafe") }
1381 | 'safe' { L1 $! mkUnqual varName FSLIT("safe") }
1382 | 'threadsafe' { L1 $! mkUnqual varName FSLIT("threadsafe") }
1384 varid_no_unsafe :: { Located RdrName }
1385 : VARID { L1 $! mkUnqual varName (getVARID $1) }
1386 | special_id { L1 $! mkUnqual varName (unLoc $1) }
1387 | 'forall' { L1 $! mkUnqual varName FSLIT("forall") }
1389 tyvar :: { Located RdrName }
1390 : VARID { L1 $! mkUnqual tvName (getVARID $1) }
1391 | special_id { L1 $! mkUnqual tvName (unLoc $1) }
1392 | 'unsafe' { L1 $! mkUnqual tvName FSLIT("unsafe") }
1393 | 'safe' { L1 $! mkUnqual tvName FSLIT("safe") }
1394 | 'threadsafe' { L1 $! mkUnqual tvName FSLIT("threadsafe") }
1396 -- These special_ids are treated as keywords in various places,
1397 -- but as ordinary ids elsewhere. 'special_id' collects all these
1398 -- except 'unsafe' and 'forall' whose treatment differs depending on context
1399 special_id :: { Located UserFS }
1401 : 'as' { L1 FSLIT("as") }
1402 | 'qualified' { L1 FSLIT("qualified") }
1403 | 'hiding' { L1 FSLIT("hiding") }
1404 | 'export' { L1 FSLIT("export") }
1405 | 'label' { L1 FSLIT("label") }
1406 | 'dynamic' { L1 FSLIT("dynamic") }
1407 | 'stdcall' { L1 FSLIT("stdcall") }
1408 | 'ccall' { L1 FSLIT("ccall") }
1410 -----------------------------------------------------------------------------
1413 qvarsym :: { Located RdrName }
1417 qvarsym_no_minus :: { Located RdrName }
1418 : varsym_no_minus { $1 }
1421 qvarsym1 :: { Located RdrName }
1422 qvarsym1 : QVARSYM { L1 $ mkQual varName (getQVARSYM $1) }
1424 varsym :: { Located RdrName }
1425 : varsym_no_minus { $1 }
1426 | '-' { L1 $ mkUnqual varName FSLIT("-") }
1428 varsym_no_minus :: { Located RdrName } -- varsym not including '-'
1429 : VARSYM { L1 $ mkUnqual varName (getVARSYM $1) }
1430 | special_sym { L1 $ mkUnqual varName (unLoc $1) }
1433 -- See comments with special_id
1434 special_sym :: { Located UserFS }
1435 special_sym : '!' { L1 FSLIT("!") }
1436 | '.' { L1 FSLIT(".") }
1437 | '*' { L1 FSLIT("*") }
1439 -----------------------------------------------------------------------------
1440 -- Data constructors
1442 qconid :: { Located RdrName } -- Qualified or unqualifiedb
1444 | QCONID { L1 $ mkQual dataName (getQCONID $1) }
1446 conid :: { Located RdrName }
1447 : CONID { L1 $ mkUnqual dataName (getCONID $1) }
1449 qconsym :: { Located RdrName } -- Qualified or unqualified
1451 | QCONSYM { L1 $ mkQual dataName (getQCONSYM $1) }
1453 consym :: { Located RdrName }
1454 : CONSYM { L1 $ mkUnqual dataName (getCONSYM $1) }
1456 -- ':' means only list cons
1457 | ':' { L1 $ consDataCon_RDR }
1460 -----------------------------------------------------------------------------
1463 literal :: { Located HsLit }
1464 : CHAR { L1 $ HsChar $ getCHAR $1 }
1465 | STRING { L1 $ HsString $ getSTRING $1 }
1466 | PRIMINTEGER { L1 $ HsIntPrim $ getPRIMINTEGER $1 }
1467 | PRIMCHAR { L1 $ HsCharPrim $ getPRIMCHAR $1 }
1468 | PRIMSTRING { L1 $ HsStringPrim $ getPRIMSTRING $1 }
1469 | PRIMFLOAT { L1 $ HsFloatPrim $ getPRIMFLOAT $1 }
1470 | PRIMDOUBLE { L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }
1472 -----------------------------------------------------------------------------
1476 : vccurly { () } -- context popped in lexer.
1477 | error {% popContext }
1479 -----------------------------------------------------------------------------
1480 -- Miscellaneous (mostly renamings)
1482 modid :: { Located ModuleName }
1483 : CONID { L1 $ mkModuleNameFS (getCONID $1) }
1484 | QCONID { L1 $ let (mod,c) = getQCONID $1 in
1487 (unpackFS mod ++ '.':unpackFS c))
1491 : commas ',' { $1 + 1 }
1494 -----------------------------------------------------------------------------
1498 happyError = srcParseFail
1500 getVARID (L _ (ITvarid x)) = x
1501 getCONID (L _ (ITconid x)) = x
1502 getVARSYM (L _ (ITvarsym x)) = x
1503 getCONSYM (L _ (ITconsym x)) = x
1504 getQVARID (L _ (ITqvarid x)) = x
1505 getQCONID (L _ (ITqconid x)) = x
1506 getQVARSYM (L _ (ITqvarsym x)) = x
1507 getQCONSYM (L _ (ITqconsym x)) = x
1508 getIPDUPVARID (L _ (ITdupipvarid x)) = x
1509 getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
1510 getCHAR (L _ (ITchar x)) = x
1511 getSTRING (L _ (ITstring x)) = x
1512 getINTEGER (L _ (ITinteger x)) = x
1513 getRATIONAL (L _ (ITrational x)) = x
1514 getPRIMCHAR (L _ (ITprimchar x)) = x
1515 getPRIMSTRING (L _ (ITprimstring x)) = x
1516 getPRIMINTEGER (L _ (ITprimint x)) = x
1517 getPRIMFLOAT (L _ (ITprimfloat x)) = x
1518 getPRIMDOUBLE (L _ (ITprimdouble x)) = x
1519 getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1521 -- Utilities for combining source spans
1522 comb2 :: Located a -> Located b -> SrcSpan
1525 comb3 :: Located a -> Located b -> Located c -> SrcSpan
1526 comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))
1528 comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
1529 comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
1530 combineSrcSpans (getLoc c) (getLoc d)
1532 -- strict constructor version:
1534 sL :: SrcSpan -> a -> Located a
1535 sL span a = span `seq` L span a
1537 -- Make a source location that is just the filename. This seems slightly
1538 -- neater than trying to construct the span of the text within the file.
1539 fileSrcSpan :: P SrcSpan
1540 fileSrcSpan = do l <- getSrcLoc; return (mkGeneralSrcSpan (srcLocFile l))