Parser.y.pp 55.2 KB
Newer Older
1 2 3 4 5 6 7 8 9 10
--								-*-haskell-*-
-- ---------------------------------------------------------------------------
-- (c) The University of Glasgow 1997-2003
---
-- The GHC grammar.
--
-- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
-- ---------------------------------------------------------------------------

{
11
module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
12
		parseHeader ) where
13 14 15 16 17 18

#define INCLUDE #include 
INCLUDE "HsVersions.h"

import HsSyn
import RdrHsSyn
19
import HscTypes		( IsBootInterface, DeprecTxt )
20 21 22 23 24
import Lexer
import RdrName
import TysWiredIn	( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
			  listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR )
import Type		( funTyCon )
25
import ForeignCall	( Safety(..), CExportSpec(..), CLabelString,
26 27
			  CCallConv(..), CCallTarget(..), defaultCCallConv
			)
28
import OccName		( varName, dataName, tcClsName, tvName )
29 30
import DataCon		( DataCon, dataConName )
import SrcLoc		( Located(..), unLoc, getLoc, noLoc, combineSrcSpans,
31 32
			  SrcSpan, combineLocs, srcLocFile, 
			  mkSrcLoc, mkSrcSpan )
33
import Module
34
import StaticFlags	( opt_SccProfilingOn )
35 36
import Type		( Kind, mkArrowKind, liftedTypeKind )
import BasicTypes	( Boxity(..), Fixity(..), FixityDirection(..), IPName(..),
37
			  Activation(..), defaultInlineSpec )
38
import OrdList
39 40 41 42

import FastString
import Maybes		( orElse )
import Outputable
43
import GLAEXTS
44 45 46 47
}

{-
-----------------------------------------------------------------------------
48
Conflicts: 36 shift/reduce (1.25)
49

50
10 for abiguity in 'if x then y else z + 1'		[State 178]
51 52 53
	(shift parses as 'if x then y else (z + 1)', as per longest-parse rule)
	10 because op might be: : - ! * . `x` VARSYM CONSYM QVARSYM QCONSYM

54
1 for ambiguity in 'if x then y else z :: T'		[State 178]
55 56
	(shift parses as 'if x then y else (z :: T)', as per longest-parse rule)

57
4 for ambiguity in 'if x then y else z -< e'		[State 178]
58
	(shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
59 60 61 62 63 64 65 66 67 68
	There are four such operators: -<, >-, -<<, >>-


2 for ambiguity in 'case v of { x :: T -> T ... } ' 	[States 11, 253]
 	Which of these two is intended?
	  case v of
	    (x::T) -> T		-- Rhs is T
    or
	  case v of
	    (x::T -> T) -> ..	-- Rhs is ...
69

70
10 for ambiguity in 'e :: a `b` c'.  Does this mean 	[States 11, 253]
71 72
	(e::a) `b` c, or 
	(e :: (a `b` c))
73
    As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
74
    Same duplication between states 11 and 253 as the previous case
75

76
1 for ambiguity in 'let ?x ...'				[State 329]
77 78 79 80
	the parser can't tell whether the ?x is the lhs of a normal binding or
	an implicit binding.  Fortunately resolving as shift gives it the only
	sensible meaning, namely the lhs of an implicit binding.

81
1 for ambiguity in '{-# RULES "name" [ ... #-}		[State 382]
82 83 84 85
	we don't know whether the '[' starts the activation or not: it
  	might be the start of the declaration with the activation being
	empty.  --SDM 1/4/2002

86 87 88 89 90
6 for conflicts between `fdecl' and `fdeclDEPRECATED', 	[States 393,394]
  	which are resolved correctly, and moreover, 
  	should go away when `fdeclDEPRECATED' is removed.

1 for ambiguity in '{-# RULES "name" forall = ... #-}' 	[State 474]
91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185
	since 'forall' is a valid variable name, we don't know whether
	to treat a forall on the input as the beginning of a quantifier
	or the beginning of the rule itself.  Resolving to shift means
	it's always treated as a quantifier, hence the above is disallowed.
	This saves explicitly defining a grammar for the rule lhs that
	doesn't include 'forall'.

-- ---------------------------------------------------------------------------
-- Adding location info

This is done in a stylised way using the three macros below, L0, L1
and LL.  Each of these macros can be thought of as having type

   L0, L1, LL :: a -> Located a

They each add a SrcSpan to their argument.

   L0	adds 'noSrcSpan', used for empty productions

   L1   for a production with a single token on the lhs.  Grabs the SrcSpan
	from that token.

   LL   for a production with >1 token on the lhs.  Makes up a SrcSpan from
        the first and last tokens.

These suffice for the majority of cases.  However, we must be
especially careful with empty productions: LL won't work if the first
or last token on the lhs can represent an empty span.  In these cases,
we have to calculate the span using more of the tokens from the lhs, eg.

	| 'newtype' tycl_hdr '=' newconstr deriving
		{ L (comb3 $1 $4 $5)
		    (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }

We provide comb3 and comb4 functions which are useful in such cases.

Be careful: there's no checking that you actually got this right, the
only symptom will be that the SrcSpans of your syntax will be
incorrect.

/*
 * We must expand these macros *before* running Happy, which is why this file is
 * Parser.y.pp rather than just Parser.y - we run the C pre-processor first.
 */
#define L0   L noSrcSpan
#define L1   sL (getLoc $1)
#define LL   sL (comb2 $1 $>)

-- -----------------------------------------------------------------------------

-}

%token
 '_'            { L _ ITunderscore }		-- Haskell keywords
 'as' 		{ L _ ITas }
 'case' 	{ L _ ITcase }  	
 'class' 	{ L _ ITclass } 
 'data' 	{ L _ ITdata } 
 'default' 	{ L _ ITdefault }
 'deriving' 	{ L _ ITderiving }
 'do' 		{ L _ ITdo }
 'else' 	{ L _ ITelse }
 'hiding' 	{ L _ IThiding }
 'if' 		{ L _ ITif }
 'import' 	{ L _ ITimport }
 'in' 		{ L _ ITin }
 'infix' 	{ L _ ITinfix }
 'infixl' 	{ L _ ITinfixl }
 'infixr' 	{ L _ ITinfixr }
 'instance' 	{ L _ ITinstance }
 'let' 		{ L _ ITlet }
 'module' 	{ L _ ITmodule }
 'newtype' 	{ L _ ITnewtype }
 'of' 		{ L _ ITof }
 'qualified' 	{ L _ ITqualified }
 'then' 	{ L _ ITthen }
 'type' 	{ L _ ITtype }
 'where' 	{ L _ ITwhere }
 '_scc_'	{ L _ ITscc }	      -- ToDo: remove

 'forall'	{ L _ ITforall }			-- GHC extension keywords
 'foreign'	{ L _ ITforeign }
 'export'	{ L _ ITexport }
 'label'	{ L _ ITlabel } 
 'dynamic'	{ L _ ITdynamic }
 'safe'		{ L _ ITsafe }
 'threadsafe'	{ L _ ITthreadsafe }
 'unsafe'	{ L _ ITunsafe }
 'mdo'		{ L _ ITmdo }
 'stdcall'      { L _ ITstdcallconv }
 'ccall'        { L _ ITccallconv }
 'dotnet'       { L _ ITdotnet }
 'proc'		{ L _ ITproc }		-- for arrow notation extension
 'rec'		{ L _ ITrec }		-- for arrow notation extension

186 187 188
 '{-# INLINE'      	  { L _ (ITinline_prag _) }
 '{-# SPECIALISE'  	  { L _ ITspec_prag }
 '{-# SPECIALISE_INLINE'  { L _ (ITspec_inline_prag _) }
189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275
 '{-# SOURCE'	   { L _ ITsource_prag }
 '{-# RULES'	   { L _ ITrules_prag }
 '{-# CORE'        { L _ ITcore_prag }              -- hdaume: annotated core
 '{-# SCC'	   { L _ ITscc_prag }
 '{-# DEPRECATED'  { L _ ITdeprecated_prag }
 '{-# UNPACK'      { L _ ITunpack_prag }
 '#-}'		   { L _ ITclose_prag }

 '..'		{ L _ ITdotdot }  			-- reserved symbols
 ':'		{ L _ ITcolon }
 '::'		{ L _ ITdcolon }
 '='		{ L _ ITequal }
 '\\'		{ L _ ITlam }
 '|'		{ L _ ITvbar }
 '<-'		{ L _ ITlarrow }
 '->'		{ L _ ITrarrow }
 '@'		{ L _ ITat }
 '~'		{ L _ ITtilde }
 '=>'		{ L _ ITdarrow }
 '-'		{ L _ ITminus }
 '!'		{ L _ ITbang }
 '*'		{ L _ ITstar }
 '-<'		{ L _ ITlarrowtail }		-- for arrow notation
 '>-'		{ L _ ITrarrowtail }		-- for arrow notation
 '-<<'		{ L _ ITLarrowtail }		-- for arrow notation
 '>>-'		{ L _ ITRarrowtail }		-- for arrow notation
 '.'		{ L _ ITdot }

 '{'		{ L _ ITocurly } 			-- special symbols
 '}'		{ L _ ITccurly }
 '{|'           { L _ ITocurlybar }
 '|}'           { L _ ITccurlybar }
 vocurly	{ L _ ITvocurly } -- virtual open curly (from layout)
 vccurly	{ L _ ITvccurly } -- virtual close curly (from layout)
 '['		{ L _ ITobrack }
 ']'		{ L _ ITcbrack }
 '[:'		{ L _ ITopabrack }
 ':]'		{ L _ ITcpabrack }
 '('		{ L _ IToparen }
 ')'		{ L _ ITcparen }
 '(#'		{ L _ IToubxparen }
 '#)'		{ L _ ITcubxparen }
 '(|'		{ L _ IToparenbar }
 '|)'		{ L _ ITcparenbar }
 ';'		{ L _ ITsemi }
 ','		{ L _ ITcomma }
 '`'		{ L _ ITbackquote }

 VARID   	{ L _ (ITvarid    _) }		-- identifiers
 CONID   	{ L _ (ITconid    _) }
 VARSYM  	{ L _ (ITvarsym   _) }
 CONSYM  	{ L _ (ITconsym   _) }
 QVARID  	{ L _ (ITqvarid   _) }
 QCONID  	{ L _ (ITqconid   _) }
 QVARSYM 	{ L _ (ITqvarsym  _) }
 QCONSYM 	{ L _ (ITqconsym  _) }

 IPDUPVARID   	{ L _ (ITdupipvarid   _) }		-- GHC extension
 IPSPLITVARID  	{ L _ (ITsplitipvarid _) }		-- GHC extension

 CHAR		{ L _ (ITchar     _) }
 STRING		{ L _ (ITstring   _) }
 INTEGER	{ L _ (ITinteger  _) }
 RATIONAL	{ L _ (ITrational _) }
		    
 PRIMCHAR	{ L _ (ITprimchar   _) }
 PRIMSTRING	{ L _ (ITprimstring _) }
 PRIMINTEGER	{ L _ (ITprimint    _) }
 PRIMFLOAT	{ L _ (ITprimfloat  _) }
 PRIMDOUBLE	{ L _ (ITprimdouble _) }
 		    
-- Template Haskell 
'[|'            { L _ ITopenExpQuote  }       
'[p|'           { L _ ITopenPatQuote  }      
'[t|'           { L _ ITopenTypQuote  }      
'[d|'           { L _ ITopenDecQuote  }      
'|]'            { L _ ITcloseQuote    }
TH_ID_SPLICE    { L _ (ITidEscape _)  }     -- $x
'$('	        { L _ ITparenEscape   }     -- $( exp )
TH_VAR_QUOTE	{ L _ ITvarQuote      }     -- 'x
TH_TY_QUOTE	{ L _ ITtyQuote       }      -- ''T

%monad { P } { >>= } { return }
%lexer { lexer } { L _ ITeof }
%name parseModule module
%name parseStmt   maybe_stmt
%name parseIdentifier  identifier
276
%name parseType ctype
277
%partial parseHeader header
278
%tokentype { (Located Token) }
279 280
%%

281 282 283 284 285 286 287 288
-----------------------------------------------------------------------------
-- Identifiers; one of the entry points
identifier :: { Located RdrName }
	: qvar				{ $1 }
	| qcon				{ $1 }
	| qvarop			{ $1 }
	| qconop			{ $1 }

289 290 291 292 293 294 295 296 297 298 299 300 301
-----------------------------------------------------------------------------
-- Module Header

-- The place for module deprecation is really too restrictive, but if it
-- was allowed at its natural place just before 'module', we get an ugly
-- s/r conflict with the second alternative. Another solution would be the
-- introduction of a new pragma DEPRECATED_MODULE, but this is not very nice,
-- either, and DEPRECATED is only expected to be used by people who really
-- know what they are doing. :-)

module 	:: { Located (HsModule RdrName) }
 	: 'module' modid maybemoddeprec maybeexports 'where' body 
		{% fileSrcSpan >>= \ loc ->
302
		   return (L loc (HsModule (Just $2) $4 (fst $6) (snd $6) $3)) }
303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326
	| missing_module_keyword top close
		{% fileSrcSpan >>= \ loc ->
		   return (L loc (HsModule Nothing Nothing 
				(fst $2) (snd $2) Nothing)) }

missing_module_keyword :: { () }
	: {- empty -}				{% pushCurrentContext }

maybemoddeprec :: { Maybe DeprecTxt }
	: '{-# DEPRECATED' STRING '#-}' 	{ Just (getSTRING $2) }
	|  {- empty -}				{ Nothing }

body 	:: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
	:  '{'            top '}'		{ $2 }
 	|      vocurly    top close		{ $2 }

top 	:: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
	: importdecls				{ (reverse $1,[]) }
	| importdecls ';' cvtopdecls		{ (reverse $1,$3) }
	| cvtopdecls				{ ([],$1) }

cvtopdecls :: { [LHsDecl RdrName] }
	: topdecls				{ cvTopDecls $1 }

327 328 329 330 331 332 333 334 335 336 337 338 339 340 341
-----------------------------------------------------------------------------
-- Module declaration & imports only

header 	:: { Located (HsModule RdrName) }
 	: 'module' modid maybemoddeprec maybeexports 'where' header_body
		{% fileSrcSpan >>= \ loc ->
		   return (L loc (HsModule (Just $2) $4 $6 [] $3)) }
	| missing_module_keyword importdecls
		{% fileSrcSpan >>= \ loc ->
		   return (L loc (HsModule Nothing Nothing $2 [] Nothing)) }

header_body :: { [LImportDecl RdrName] }
	:  '{'            importdecls		{ $2 }
 	|      vocurly    importdecls		{ $2 }

342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370
-----------------------------------------------------------------------------
-- The Export List

maybeexports :: { Maybe [LIE RdrName] }
	:  '(' exportlist ')'			{ Just $2 }
	|  {- empty -}				{ Nothing }

exportlist :: { [LIE RdrName] }
 	:  exportlist ',' export		{ $3 : $1 }
	|  exportlist ','			{ $1 }
 	|  export				{ [$1]  }
	|  {- empty -}				{ [] }

   -- No longer allow things like [] and (,,,) to be exported
   -- They are built in syntax, always available
export 	:: { LIE RdrName }
	:  qvar				{ L1 (IEVar (unLoc $1)) }
	|  oqtycon			{ L1 (IEThingAbs (unLoc $1)) }
	|  oqtycon '(' '..' ')'		{ LL (IEThingAll (unLoc $1)) }
	|  oqtycon '(' ')'		{ LL (IEThingWith (unLoc $1) []) }
	|  oqtycon '(' qcnames ')'	{ LL (IEThingWith (unLoc $1) (reverse $3)) }
	|  'module' modid		{ LL (IEModuleContents (unLoc $2)) }

qcnames :: { [RdrName] }
	:  qcnames ',' qcname			{ unLoc $3 : $1 }
	|  qcname				{ [unLoc $1]  }

qcname 	:: { Located RdrName }	-- Variable or data constructor
	:  qvar					{ $1 }
371
	|  qcon					{ $1 }
372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396

-----------------------------------------------------------------------------
-- Import Declarations

-- import decls can be *empty*, or even just a string of semicolons
-- whereas topdecls must contain at least one topdecl.

importdecls :: { [LImportDecl RdrName] }
	: importdecls ';' importdecl		{ $3 : $1 }
	| importdecls ';'			{ $1 }
	| importdecl				{ [ $1 ] }
	| {- empty -}				{ [] }

importdecl :: { LImportDecl RdrName }
	: 'import' maybe_src optqualified modid maybeas maybeimpspec 
		{ L (comb4 $1 $4 $5 $6) (ImportDecl $4 $2 $3 (unLoc $5) (unLoc $6)) }

maybe_src :: { IsBootInterface }
	: '{-# SOURCE' '#-}'			{ True }
	| {- empty -}				{ False }

optqualified :: { Bool }
      	: 'qualified'                           { True  }
      	| {- empty -}				{ False }

397
maybeas :: { Located (Maybe Module) }
398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427
      	: 'as' modid                            { LL (Just (unLoc $2)) }
      	| {- empty -}				{ noLoc Nothing }

maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
	: impspec				{ L1 (Just (unLoc $1)) }
	| {- empty -}				{ noLoc Nothing }

impspec :: { Located (Bool, [LIE RdrName]) }
	:  '(' exportlist ')'  			{ LL (False, reverse $2) }
	|  'hiding' '(' exportlist ')' 		{ LL (True,  reverse $3) }

-----------------------------------------------------------------------------
-- Fixity Declarations

prec 	:: { Int }
	: {- empty -}		{ 9 }
	| INTEGER		{% checkPrecP (L1 (fromInteger (getINTEGER $1))) }

infix 	:: { Located FixityDirection }
	: 'infix'				{ L1 InfixN  }
	| 'infixl'				{ L1 InfixL  }
	| 'infixr'				{ L1 InfixR }

ops   	:: { Located [Located RdrName] }
	: ops ',' op				{ LL ($3 : unLoc $1) }
	| op					{ L1 [$1] }

-----------------------------------------------------------------------------
-- Top-Level Declarations

428 429
topdecls :: { OrdList (LHsDecl RdrName) }	-- Reversed
	: topdecls ';' topdecl		{ $1 `appOL` $3 }
430
	| topdecls ';'			{ $1 }
431
	| topdecl			{ $1 }
432

433 434
topdecl :: { OrdList (LHsDecl RdrName) }
  	: tycl_decl			{ unitOL (L1 (TyClD (unLoc $1))) }
435 436
	| 'instance' inst_type where
		{ let (binds,sigs) = cvBindsAndSigs (unLoc $3)
437 438 439 440 441 442
		  in unitOL (L (comb3 $1 $2 $3) (InstD (InstDecl $2 binds sigs))) }
	| 'default' '(' comma_types0 ')'	{ unitOL (LL $ DefD (DefaultDecl $3)) }
	| 'foreign' fdecl			{ unitOL (LL (unLoc $2)) }
	| '{-# DEPRECATED' deprecations '#-}'	{ $2 }
	| '{-# RULES' rules '#-}'		{ $2 }
	| '$(' exp ')'				{ unitOL (LL $ SpliceD (SpliceDecl $2)) }
443 444 445
      	| decl					{ unLoc $1 }

tycl_decl :: { LTyClDecl RdrName }
446 447 448 449 450
 	: 'type' type '=' ctype	
		-- Note type on the left of the '='; this allows
		-- infix type constructors to be declared
		-- 
		-- Note ctype, not sigtype, on the right
451 452 453
		-- We allow an explicit for-all but we don't insert one
		-- in 	type Foo a = (b,b)
		-- Instead we just say b is out of scope
454 455
 		{% do { (tc,tvs) <- checkSynHdr $2
		      ; return (LL (TySynonym tc tvs $4)) } }
456

457
	| data_or_newtype tycl_hdr constrs deriving
458 459
		{ L (comb4 $1 $2 $3 $4)	-- We need the location on tycl_hdr 
					-- in case constrs and deriving are both empty
460
		    (mkTyData (unLoc $1) (unLoc $2) Nothing (reverse (unLoc $3)) (unLoc $4)) }
461

462
        | data_or_newtype tycl_hdr opt_kind_sig 
463
		 'where' gadt_constrlist
464
		 deriving
465
		{ L (comb4 $1 $2 $4 $5)
466
		    (mkTyData (unLoc $1) (unLoc $2) $3 (reverse (unLoc $5)) (unLoc $6)) }
467 468 469 470 471 472 473 474

	| 'class' tycl_hdr fds where
		{ let 
			(binds,sigs) = cvBindsAndSigs (unLoc $4)
		  in
	 	  L (comb4 $1 $2 $3 $4) (mkClassDecl (unLoc $2) (unLoc $3) sigs 
					  binds) }

475 476 477 478
data_or_newtype :: { Located NewOrData }
	: 'data'	{ L1 DataType }
	| 'newtype'	{ L1 NewType }

479 480 481 482
opt_kind_sig :: { Maybe Kind }
	: 				{ Nothing }
	| '::' kind			{ Just $2 }

483 484 485 486 487 488 489
-- tycl_hdr parses the header of a type or class decl,
-- which takes the form
--	T a b
-- 	Eq a => T a
--	(Eq a, Ord b) => T a b
-- Rather a lot of inlining here, else we get reduce/reduce errors
tycl_hdr :: { Located (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName]) }
490
	: context '=>' type		{% checkTyClHdr $1         $3 >>= return.LL }
491 492 493 494 495
	| type				{% checkTyClHdr (noLoc []) $1 >>= return.L1 }

-----------------------------------------------------------------------------
-- Nested declarations

496 497
decls 	:: { Located (OrdList (LHsDecl RdrName)) }	-- Reversed
	: decls ';' decl		{ LL (unLoc $1 `appOL` unLoc $3) }
498
	| decls ';'			{ LL (unLoc $1) }
499
	| decl				{ $1 }
500
	| {- empty -}			{ noLoc nilOL }
501 502


503
decllist :: { Located (OrdList (LHsDecl RdrName)) }	-- Reversed
504 505 506
	: '{'            decls '}'	{ LL (unLoc $2) }
	|     vocurly    decls close	{ $2 }

507
where 	:: { Located (OrdList (LHsDecl RdrName)) }	-- Reversed
508 509
				-- No implicit parameters
	: 'where' decllist		{ LL (unLoc $2) }
510
	| {- empty -}			{ noLoc nilOL }
511

512 513 514 515
binds 	::  { Located (HsLocalBinds RdrName) } 		-- May have implicit parameters
	: decllist			{ L1 (HsValBinds (cvBindGroup (unLoc $1))) }
	| '{'            dbinds '}'	{ LL (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
	|     vocurly    dbinds close	{ L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyLHsBinds)) }
516

517
wherebinds :: { Located (HsLocalBinds RdrName) }	-- May have implicit parameters
518
	: 'where' binds			{ LL (unLoc $2) }
519
	| {- empty -}			{ noLoc emptyLocalBinds }
520 521 522 523 524


-----------------------------------------------------------------------------
-- Transformation Rules

525 526
rules	:: { OrdList (LHsDecl RdrName) }	-- Reversed
	:  rules ';' rule			{ $1 `snocOL` $3 }
527
        |  rules ';'				{ $1 }
528 529
        |  rule					{ unitOL $1 }
	|  {- empty -}				{ nilOL }
530

531
rule  	:: { LHsDecl RdrName }
532
	: STRING activation rule_forall infixexp '=' exp
533 534
	     { LL $ RuleD (HsRule (getSTRING $1) 
				  ($2 `orElse` AlwaysActive) 
535
				  $3 $4 placeHolderNames $6 placeHolderNames) }
536

537 538 539
activation :: { Maybe Activation } 
        : {- empty -}                           { Nothing }
        | explicit_activation                   { Just $1 }
540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559

explicit_activation :: { Activation }  -- In brackets
        : '[' INTEGER ']'		{ ActiveAfter  (fromInteger (getINTEGER $2)) }
        | '[' '~' INTEGER ']'		{ ActiveBefore (fromInteger (getINTEGER $3)) }

rule_forall :: { [RuleBndr RdrName] }
	: 'forall' rule_var_list '.'            { $2 }
        | {- empty -}				{ [] }

rule_var_list :: { [RuleBndr RdrName] }
        : rule_var				{ [$1] }
        | rule_var rule_var_list		{ $1 : $2 }

rule_var :: { RuleBndr RdrName }
	: varid                              	{ RuleBndr $1 }
       	| '(' varid '::' ctype ')'             	{ RuleBndrSig $2 $4 }

-----------------------------------------------------------------------------
-- Deprecations (c.f. rules)

560 561
deprecations :: { OrdList (LHsDecl RdrName) }	-- Reversed
	: deprecations ';' deprecation		{ $1 `appOL` $3 }
562
	| deprecations ';' 			{ $1 }
563 564
	| deprecation				{ $1 }
	| {- empty -}				{ nilOL }
565 566

-- SUP: TEMPORARY HACK, not checking for `module Foo'
567
deprecation :: { OrdList (LHsDecl RdrName) }
568
	: depreclist STRING
569 570
		{ toOL [ LL $ DeprecD (Deprecation n (getSTRING $2)) 
		       | n <- unLoc $1 ] }
571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735


-----------------------------------------------------------------------------
-- Foreign import and export declarations

-- for the time being, the following accepts foreign declarations conforming
-- to the FFI Addendum, Version 1.0 as well as pre-standard declarations
--
-- * a flag indicates whether pre-standard declarations have been used and
--   triggers a deprecation warning further down the road
--
-- NB: The first two rules could be combined into one by replacing `safety1'
--     with `safety'.  However, the combined rule conflicts with the
--     DEPRECATED rules.
--
fdecl :: { LHsDecl RdrName }
fdecl : 'import' callconv safety1 fspec
		{% mkImport $2 $3 (unLoc $4) >>= return.LL }
      | 'import' callconv         fspec		
		{% do { d <- mkImport $2 (PlaySafe False) (unLoc $3);
			return (LL d) } }
      | 'export' callconv fspec
		{% mkExport $2 (unLoc $3) >>= return.LL }
        -- the following syntax is DEPRECATED
      | fdecl1DEPRECATED			{ L1 (ForD (unLoc $1)) }
      | fdecl2DEPRECATED			{ L1 (unLoc $1) }

fdecl1DEPRECATED :: { LForeignDecl RdrName }
fdecl1DEPRECATED 
  ----------- DEPRECATED label decls ------------
  : 'label' ext_name varid '::' sigtype
    { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS 
				   (CLabel ($2 `orElse` mkExtName (unLoc $3)))) True }

  ----------- DEPRECATED ccall/stdcall decls ------------
  --
  -- NB: This business with the case expression below may seem overly
  --	 complicated, but it is necessary to avoid some conflicts.

    -- DEPRECATED variant #1: lack of a calling convention specification
    --			      (import) 
  | 'import' {-no callconv-} ext_name safety varid_no_unsafe '::' sigtype
    { let
	target = StaticTarget ($2 `orElse` mkExtName (unLoc $4))
      in
      LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS 
				   (CFunction target)) True }

    -- DEPRECATED variant #2: external name consists of two separate strings
    --			      (module name and function name) (import)
  | 'import' callconv STRING STRING safety varid_no_unsafe '::' sigtype
    {% case $2 of
         DNCall      -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
	 CCall cconv -> return $
           let
	     imp = CFunction (StaticTarget (getSTRING $4))
	   in
	   LL $ ForeignImport $6 $8 (CImport cconv $5 nilFS nilFS imp) True }

    -- DEPRECATED variant #3: `unsafe' after entity
  | 'import' callconv STRING 'unsafe' varid_no_unsafe '::' sigtype
    {% case $2 of
         DNCall      -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
	 CCall cconv -> return $
           let
	     imp = CFunction (StaticTarget (getSTRING $3))
	   in
	   LL $ ForeignImport $5 $7 (CImport cconv PlayRisky nilFS nilFS imp) True }

    -- DEPRECATED variant #4: use of the special identifier `dynamic' without
    --			      an explicit calling convention (import)
  | 'import' {-no callconv-} 'dynamic' safety varid_no_unsafe '::' sigtype
    { LL $ ForeignImport $4 $6 (CImport defaultCCallConv $3 nilFS nilFS 
				   (CFunction DynamicTarget)) True }

    -- DEPRECATED variant #5: use of the special identifier `dynamic' (import)
  | 'import' callconv 'dynamic' safety varid_no_unsafe '::' sigtype
    {% case $2 of
         DNCall      -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
	 CCall cconv -> return $
	   LL $ ForeignImport $5 $7 (CImport cconv $4 nilFS nilFS 
					(CFunction DynamicTarget)) True }

    -- DEPRECATED variant #6: lack of a calling convention specification
    --			      (export) 
  | 'export' {-no callconv-} ext_name varid '::' sigtype
    { LL $ ForeignExport $3 $5 (CExport (CExportStatic ($2 `orElse` mkExtName (unLoc $3))
				   defaultCCallConv)) True }

    -- DEPRECATED variant #7: external name consists of two separate strings
    --			      (module name and function name) (export)
  | 'export' callconv STRING STRING varid '::' sigtype
    {% case $2 of
         DNCall      -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
	 CCall cconv -> return $
           LL $ ForeignExport $5 $7 
			 (CExport (CExportStatic (getSTRING $4) cconv)) True }

    -- DEPRECATED variant #8: use of the special identifier `dynamic' without
    --			      an explicit calling convention (export)
  | 'export' {-no callconv-} 'dynamic' varid '::' sigtype
    { LL $ ForeignImport $3 $5 (CImport defaultCCallConv (PlaySafe False) nilFS nilFS 
				   CWrapper) True }

    -- DEPRECATED variant #9: use of the special identifier `dynamic' (export)
  | 'export' callconv 'dynamic' varid '::' sigtype
    {% case $2 of
         DNCall      -> parseError (comb2 $1 $>) "Illegal format of .NET foreign import"
	 CCall cconv -> return $
	   LL $ ForeignImport $4 $6 
		 (CImport cconv (PlaySafe False) nilFS nilFS CWrapper) True }

  ----------- DEPRECATED .NET decls ------------
  -- NB: removed the .NET call declaration, as it is entirely subsumed
  --     by the new standard FFI declarations

fdecl2DEPRECATED :: { LHsDecl RdrName }
fdecl2DEPRECATED 
  : 'import' 'dotnet' 'type' ext_name tycon { LL $ TyClD (ForeignType $5 $4 DNType) }
    -- left this one unchanged for the moment as type imports are not
    -- covered currently by the FFI standard -=chak


callconv :: { CallConv }
	  : 'stdcall'			{ CCall  StdCallConv }
	  | 'ccall'			{ CCall  CCallConv   }
	  | 'dotnet'			{ DNCall	     }

safety :: { Safety }
	: 'unsafe'			{ PlayRisky }
	| 'safe'			{ PlaySafe False }
	| 'threadsafe'			{ PlaySafe True  }
	| {- empty -}			{ PlaySafe False }

safety1 :: { Safety }
	: 'unsafe'			{ PlayRisky }
	| 'safe'			{ PlaySafe  False }
	| 'threadsafe'			{ PlaySafe  True }
	  -- only needed to avoid conflicts with the DEPRECATED rules

fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
       : STRING var '::' sigtype      { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
       |        var '::' sigtype      { LL (noLoc nilFS, $1, $3) }
         -- if the entity string is missing, it defaults to the empty string;
         -- the meaning of an empty entity string depends on the calling
         -- convention

-- DEPRECATED syntax
ext_name :: { Maybe CLabelString }
	: STRING		{ Just (getSTRING $1) }
	| STRING STRING		{ Just (getSTRING $2) }	-- Ignore "module name" for now
	| {- empty -}           { Nothing }


-----------------------------------------------------------------------------
-- Type signatures

opt_sig :: { Maybe (LHsType RdrName) }
	: {- empty -}			{ Nothing }
	| '::' sigtype			{ Just $2 }

opt_asig :: { Maybe (LHsType RdrName) }
	: {- empty -}			{ Nothing }
	| '::' atype			{ Just $2 }

736
sigtypes1 :: { [LHsType RdrName] }
737
	: sigtype			{ [ $1 ] }
738
	| sigtype ',' sigtypes1		{ $1 : $3 }
739 740 741 742 743 744 745 746 747 748 749 750

sigtype :: { LHsType RdrName }
	: ctype				{ L1 (mkImplicitHsForAllTy (noLoc []) $1) }
	-- Wrap an Implicit forall if there isn't one there already

sig_vars :: { Located [Located RdrName] }
	 : sig_vars ',' var		{ LL ($3 : unLoc $1) }
	 | var				{ L1 [$1] }

-----------------------------------------------------------------------------
-- Types

751 752 753 754
strict_mark :: { Located HsBang }
	: '!'				{ L1 HsStrict }
	| '{-# UNPACK' '#-}' '!'	{ LL HsUnbox }

755 756 757 758 759 760 761 762 763 764 765 766 767 768 769
-- A ctype is a for-all type
ctype	:: { LHsType RdrName }
	: 'forall' tv_bndrs '.' ctype	{ LL $ mkExplicitHsForAllTy $2 (noLoc []) $4 }
	| context '=>' type		{ LL $ mkImplicitHsForAllTy   $1 $3 }
	-- A type of form (context => type) is an *implicit* HsForAllTy
	| type				{ $1 }

-- We parse a context as a btype so that we don't get reduce/reduce
-- errors in ctype.  The basic problem is that
--	(Eq a, Ord a)
-- looks so much like a tuple type.  We can't tell until we find the =>
context :: { LHsContext RdrName }
	: btype 			{% checkContext $1 }

type :: { LHsType RdrName }
770
	: ipvar '::' gentype		{ LL (HsPredTy (HsIParam (unLoc $1) $3)) }
771 772 773 774 775
	| gentype			{ $1 }

gentype :: { LHsType RdrName }
        : btype                         { $1 }
        | btype qtyconop gentype        { LL $ HsOpTy $1 $2 $3 }
776
        | btype tyvarop  gentype  	{ LL $ HsOpTy $1 $2 $3 }
777
 	| btype '->' ctype		{ LL $ HsFunTy $1 $3 }
778 779 780 781 782 783 784

btype :: { LHsType RdrName }
	: btype atype			{ LL $ HsAppTy $1 $2 }
	| atype				{ $1 }

atype :: { LHsType RdrName }
	: gtycon			{ L1 (HsTyVar (unLoc $1)) }
785
	| tyvar				{ L1 (HsTyVar (unLoc $1)) }
786
	| strict_mark atype		{ LL (HsBangTy (unLoc $1) $2) }
787
	| '(' ctype ',' comma_types1 ')'  { LL $ HsTupleTy Boxed  ($2:$4) }
788
	| '(#' comma_types1 '#)'	{ LL $ HsTupleTy Unboxed $2     }
789 790
	| '[' ctype ']'			{ LL $ HsListTy  $2 }
	| '[:' ctype ':]'		{ LL $ HsPArrTy  $2 }
791 792 793 794 795 796 797 798 799 800
	| '(' ctype ')'		        { LL $ HsParTy   $2 }
	| '(' ctype '::' kind ')'	{ LL $ HsKindSig $2 $4 }
-- Generics
        | INTEGER                       { L1 (HsNumTy (getINTEGER $1)) }

-- An inst_type is what occurs in the head of an instance decl
--	e.g.  (Foo a, Gaz b) => Wibble a b
-- It's kept as a single type, with a MonoDictTy at the right
-- hand corner, for convenience.
inst_type :: { LHsType RdrName }
801
	: sigtype			{% checkInstType $1 }
802

803 804 805 806
inst_types1 :: { [LHsType RdrName] }
	: inst_type			{ [$1] }
	| inst_type ',' inst_types1	{ $1 : $3 }

807 808 809 810 811
comma_types0  :: { [LHsType RdrName] }
	: comma_types1			{ $1 }
	| {- empty -}			{ [] }

comma_types1	:: { [LHsType RdrName] }
812 813
	: ctype				{ [$1] }
	| ctype  ',' comma_types1	{ $1 : $3 }
814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853

tv_bndrs :: { [LHsTyVarBndr RdrName] }
	 : tv_bndr tv_bndrs		{ $1 : $2 }
	 | {- empty -}			{ [] }

tv_bndr :: { LHsTyVarBndr RdrName }
	: tyvar				{ L1 (UserTyVar (unLoc $1)) }
	| '(' tyvar '::' kind ')'	{ LL (KindedTyVar (unLoc $2) $4) }

fds :: { Located [Located ([RdrName], [RdrName])] }
	: {- empty -}			{ noLoc [] }
	| '|' fds1			{ LL (reverse (unLoc $2)) }

fds1 :: { Located [Located ([RdrName], [RdrName])] }
	: fds1 ',' fd			{ LL ($3 : unLoc $1) }
	| fd				{ L1 [$1] }

fd :: { Located ([RdrName], [RdrName]) }
	: varids0 '->' varids0		{ L (comb3 $1 $2 $3)
					   (reverse (unLoc $1), reverse (unLoc $3)) }

varids0	:: { Located [RdrName] }
	: {- empty -}			{ noLoc [] }
	| varids0 tyvar			{ LL (unLoc $2 : unLoc $1) }

-----------------------------------------------------------------------------
-- Kinds

kind	:: { Kind }
	: akind			{ $1 }
	| akind '->' kind	{ mkArrowKind $1 $3 }

akind	:: { Kind }
	: '*'			{ liftedTypeKind }
	| '(' kind ')'		{ $2 }


-----------------------------------------------------------------------------
-- Datatype declarations

854 855 856 857 858 859
gadt_constrlist :: { Located [LConDecl RdrName] }
	: '{'            gadt_constrs '}'	{ LL (unLoc $2) }
	|     vocurly    gadt_constrs close	{ $2 }

gadt_constrs :: { Located [LConDecl RdrName] }
        : gadt_constrs ';' gadt_constr  { LL ($3 : unLoc $1) }
860
        | gadt_constrs ';' 		{ $1 }
861 862
        | gadt_constr                   { L1 [$1] } 

863 864 865 866 867 868
-- We allow the following forms:
--	C :: Eq a => a -> T a
--	C :: forall a. Eq a => !a -> T a
--	D { x,y :: a } :: T a
--	forall a. Eq a => D { x,y :: a } :: T a

869
gadt_constr :: { LConDecl RdrName }
870
        : con '::' sigtype
871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886
              { LL (mkGadtDecl $1 $3) } 
        -- Syntax: Maybe merge the record stuff with the single-case above?
        --         (to kill the mostly harmless reduce/reduce error)
        -- XXX revisit autrijus
	| constr_stuff_record '::' sigtype
		{ let (con,details) = unLoc $1 in 
		  LL (ConDecl con Implicit [] (noLoc []) details (ResTyGADT $3)) }
{-
	| forall context '=>' constr_stuff_record '::' sigtype
		{ let (con,details) = unLoc $4 in 
		  LL (ConDecl con Implicit (unLoc $1) $2 details (ResTyGADT $6)) }
	| forall constr_stuff_record '::' sigtype
		{ let (con,details) = unLoc $2 in 
		  LL (ConDecl con Implicit (unLoc $1) (noLoc []) details (ResTyGADT $4)) }
-}

887 888 889 890 891 892 893 894 895 896 897 898

constrs :: { Located [LConDecl RdrName] }
        : {- empty; a GHC extension -}  { noLoc [] }
        | '=' constrs1                  { LL (unLoc $2) }

constrs1 :: { Located [LConDecl RdrName] }
	: constrs1 '|' constr		{ LL ($3 : unLoc $1) }
	| constr			{ L1 [$1] }

constr :: { LConDecl RdrName }
	: forall context '=>' constr_stuff	
		{ let (con,details) = unLoc $4 in 
899
		  LL (ConDecl con Explicit (unLoc $1) $2 details ResTyH98) }
900 901
	| forall constr_stuff
		{ let (con,details) = unLoc $2 in 
902
		  LL (ConDecl con Explicit (unLoc $1) (noLoc []) details ResTyH98) }
903 904 905 906 907 908

forall :: { Located [LHsTyVarBndr RdrName] }
	: 'forall' tv_bndrs '.'		{ LL $2 }
	| {- empty -}			{ noLoc [] }

constr_stuff :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
909 910 911 912 913 914 915
-- We parse the constructor declaration 
--	C t1 t2
-- as a btype (treating C as a type constructor) and then convert C to be
-- a data constructor.  Reason: it might continue like this:
--	C t1 t2 %: D Int
-- in which case C really would be a type constructor.  We can't resolve this
-- ambiguity till we come across the constructor oprerator :% (or not, more usually)
916 917 918
	: btype				{% mkPrefixCon $1 [] >>= return.LL }
	| oqtycon '{' '}' 		{% mkRecCon $1 [] >>= return.LL }
	| oqtycon '{' fielddecls '}' 	{% mkRecCon $1 $3 >>= return.LL }
919
	| btype conop btype		{ LL ($2, InfixCon $1 $3) }
920

921 922 923 924
constr_stuff_record :: { Located (Located RdrName, HsConDetails RdrName (LBangType RdrName)) }
	: oqtycon '{' '}' 		{% mkRecCon $1 [] >>= return.sL (comb2 $1 $>) }
	| oqtycon '{' fielddecls '}' 	{% mkRecCon $1 $3 >>= return.sL (comb2 $1 $>) }

925 926 927 928 929
fielddecls :: { [([Located RdrName], LBangType RdrName)] }
	: fielddecl ',' fielddecls	{ unLoc $1 : $3 }
	| fielddecl			{ [unLoc $1] }

fielddecl :: { Located ([Located RdrName], LBangType RdrName) }
930
	: sig_vars '::' ctype		{ LL (reverse (unLoc $1), $3) }
931

932 933 934 935
-- We allow the odd-looking 'inst_type' in a deriving clause, so that
-- we can do deriving( forall a. C [a] ) in a newtype (GHC extension).
-- The 'C [a]' part is converted to an HsPredTy by checkInstType
-- We don't allow a context, but that's sorted out by the type checker.
936 937
deriving :: { Located (Maybe [LHsType RdrName]) }
	: {- empty -}				{ noLoc Nothing }
938 939 940
	| 'deriving' qtycon	{% do { let { L loc tv = $2 }
				      ; p <- checkInstType (L loc (HsTyVar tv))
				      ; return (LL (Just [p])) } }
941 942
	| 'deriving' '(' ')'	 		{ LL (Just []) }
	| 'deriving' '(' inst_types1 ')' 	{ LL (Just $3) }
943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968
             -- Glasgow extension: allow partial 
             -- applications in derivings

-----------------------------------------------------------------------------
-- Value definitions

{- There's an awkward overlap with a type signature.  Consider
	f :: Int -> Int = ...rhs...
   Then we can't tell whether it's a type signature or a value
   definition with a result signature until we see the '='.
   So we have to inline enough to postpone reductions until we know.
-}

{-
  ATTENTION: Dirty Hackery Ahead! If the second alternative of vars is var
  instead of qvar, we get another shift/reduce-conflict. Consider the
  following programs:
  
     { (^^) :: Int->Int ; }          Type signature; only var allowed

     { (^^) :: Int->Int = ... ; }    Value defn with result signature;
				     qvar allowed (because of instance decls)
  
  We can't tell whether to reduce var to qvar until after we've read the signatures.
-}

969
decl 	:: { Located (OrdList (LHsDecl RdrName)) }
970
	: sigdecl			{ $1 }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
971 972 973 974
	| '!' infixexp rhs		{% do { pat <- checkPattern $2;
					        return (LL $ unitOL $ LL $ ValD $ 
							PatBind (LL $ BangPat pat) (unLoc $3)
								placeHolderType placeHolderNames) } }
975
	| infixexp opt_sig rhs		{% do { r <- checkValDef $1 $2 $3;
976
						return (LL $ unitOL (LL $ ValD r)) } }
977 978

rhs	:: { Located (GRHSs RdrName) }
979 980
	: '=' exp wherebinds	{ L (comb3 $1 $2 $3) $ GRHSs (unguardedRHS $2) (unLoc $3) }
	| gdrhs	wherebinds	{ LL $ GRHSs (reverse (unLoc $1)) (unLoc $2) }
981 982 983 984 985 986

gdrhs :: { Located [LGRHS RdrName] }
	: gdrhs gdrh		{ LL ($2 : unLoc $1) }
	| gdrh			{ L1 [$1] }

gdrh :: { LGRHS RdrName }
987
	: '|' quals '=' exp  	{ sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
988

989
sigdecl :: { Located (OrdList (LHsDecl RdrName)) }
990 991
	: infixexp '::' sigtype
				{% do s <- checkValSig $1 $3; 
992
				      return (LL $ unitOL (LL $ SigD s)) }
993 994
		-- See the above notes for why we need infixexp here
	| var ',' sig_vars '::' sigtype	
995
				{ LL $ toOL [ LL $ SigD (TypeSig n $5) | n <- $1 : unLoc $3 ] }
996
	| infix prec ops	{ LL $ toOL [ LL $ SigD (FixSig (FixitySig n (Fixity $2 (unLoc $1))))
997 998
					     | n <- unLoc $3 ] }
	| '{-# INLINE'   activation qvar '#-}'	      
999
				{ LL $ unitOL (LL $ SigD (InlineSig $3 (mkInlineSpec $2 (getINLINE $1)))) }
1000
	| '{-# SPECIALISE' qvar '::' sigtypes1 '#-}'
1001
			 	{ LL $ toOL [ LL $ SigD (SpecSig $2 t defaultInlineSpec)
1002
					    | t <- $4] }
1003
	| '{-# SPECIALISE_INLINE' activation qvar '::' sigtypes1 '#-}'
1004
			 	{ LL $ toOL [ LL $ SigD (SpecSig $3 t (mkInlineSpec $2 (getSPEC_INLINE $1)))
1005
					    | t <- $5] }
1006
	| '{-# SPECIALISE' 'instance' inst_type '#-}'
1007
				{ LL $ unitOL (LL $ SigD (SpecInstSig $3)) }
1008 1009 1010 1011 1012 1013

-----------------------------------------------------------------------------
-- Expressions

exp   :: { LHsExpr RdrName }
	: infixexp '::' sigtype		{ LL $ ExprWithTySig $1 $3 }
1014 1015 1016 1017
	| infixexp '-<' exp		{ LL $ HsArrApp $1 $3 placeHolderType HsFirstOrderApp True }
	| infixexp '>-' exp		{ LL $ HsArrApp $3 $1 placeHolderType HsFirstOrderApp False }
	| infixexp '-<<' exp		{ LL $ HsArrApp $1 $3 placeHolderType HsHigherOrderApp True }
	| infixexp '>>-' exp		{ LL $ HsArrApp $3 $1 placeHolderType HsHigherOrderApp False}
1018 1019 1020 1021 1022 1023 1024 1025 1026
	| infixexp			{ $1 }

infixexp :: { LHsExpr RdrName }
	: exp10				{ $1 }
	| infixexp qop exp10		{ LL (OpApp $1 $2 (panic "fixity") $3) }

exp10 :: { LHsExpr RdrName }
	: '\\' aexp aexps opt_asig '->' exp	
			{% checkPatterns ($2 : reverse $3) >>= \ ps -> 
1027
			   return (LL $ HsLam (mkMatchGroup [LL $ Match ps $4
1028
					    (GRHSs (unguardedRHS $6) emptyLocalBinds
1029
							)])) }
1030 1031
  	| 'let' binds 'in' exp			{ LL $ HsLet (unLoc $2) $4 }
	| 'if' exp 'then' exp 'else' exp	{ LL $ HsIf $2 $4 $6 }
1032
   	| 'case' exp 'of' altslist		{ LL $ HsCase $2 (mkMatchGroup (unLoc $4)) }
1033 1034 1035
	| '-' fexp				{ LL $ mkHsNegApp $2 }

  	| 'do' stmtlist			{% let loc = comb2 $1 $2 in
1036 1037
					   checkDo loc (unLoc $2)  >>= \ (stmts,body) ->
					   return (L loc (mkHsDo DoExpr stmts body)) }
1038
  	| 'mdo' stmtlist		{% let loc = comb2 $1 $2 in
1039 1040
					   checkDo loc (unLoc $2)  >>= \ (stmts,body) ->
					   return (L loc (mkHsDo (MDoExpr noPostTcTable) stmts body)) }
1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069
        | scc_annot exp		    		{ LL $ if opt_SccProfilingOn
							then HsSCC (unLoc $1) $2
							else HsPar $2 }

	| 'proc' aexp '->' exp	
			{% checkPattern $2 >>= \ p -> 
			   return (LL $ HsProc p (LL $ HsCmdTop $4 [] 
						   placeHolderType undefined)) }
						-- TODO: is LL right here?

        | '{-# CORE' STRING '#-}' exp           { LL $ HsCoreAnn (getSTRING $2) $4 }
						    -- hdaume: core annotation
	| fexp					{ $1 }

scc_annot :: { Located FastString }
	: '_scc_' STRING			{ LL $ getSTRING $2 }
	| '{-# SCC' STRING '#-}'		{ LL $ getSTRING $2 }

fexp 	:: { LHsExpr RdrName }
	: fexp aexp				{ LL $ HsApp $1 $2 }
  	| aexp					{ $1 }

aexps 	:: { [LHsExpr RdrName] }
	: aexps aexp				{ $2 : $1 }
  	| {- empty -}				{ [] }

aexp	:: { LHsExpr RdrName }
	: qvar '@' aexp			{ LL $ EAsPat $1 $3 }
	| '~' aexp			{ LL $ ELazyPat $2 }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1070
--	| '!' aexp			{ LL $ EBangPat $2 }
1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093
	| aexp1				{ $1 }

aexp1	:: { LHsExpr RdrName }
        : aexp1 '{' fbinds '}' 	{% do { r <- mkRecConstrOrUpdate $1 (comb2 $2 $4) 
							(reverse $3);
				        return (LL r) }}
  	| aexp2			{ $1 }

-- Here was the syntax for type applications that I was planning
-- but there are difficulties (e.g. what order for type args)
-- so it's not enabled yet.
-- But this case *is* used for the left hand side of a generic definition,
-- which is parsed as an expression before being munged into a pattern
 	| qcname '{|' gentype '|}'      { LL $ HsApp (sL (getLoc $1) (HsVar (unLoc $1)))
						     (sL (getLoc $3) (HsType $3)) }

aexp2	:: { LHsExpr RdrName }
	: ipvar				{ L1 (HsIPVar $! unLoc $1) }
	| qcname			{ L1 (HsVar   $! unLoc $1) }
	| literal			{ L1 (HsLit   $! unLoc $1) }
	| INTEGER			{ L1 (HsOverLit $! mkHsIntegral (getINTEGER $1)) }
	| RATIONAL			{ L1 (HsOverLit $! mkHsFractional (getRATIONAL $1)) }
	| '(' exp ')'			{ LL (HsPar $2) }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1094
	| '(' texp ',' texps ')'	{ LL $ ExplicitTuple ($2 : reverse $4) Boxed }
1095 1096 1097 1098 1099 1100 1101 1102
	| '(#' texps '#)'		{ LL $ ExplicitTuple (reverse $2)      Unboxed }
	| '[' list ']'                  { LL (unLoc $2) }
	| '[:' parr ':]'                { LL (unLoc $2) }
	| '(' infixexp qop ')'		{ LL $ SectionL $2 $3 }
	| '(' qopm infixexp ')'		{ LL $ SectionR $2 $3 }
	| '_'				{ L1 EWildPat }
	
	-- MetaHaskell Extension
1103
	| TH_ID_SPLICE          { L1 $ HsSpliceE (mkHsSplice 
1104
					(L1 $ HsVar (mkUnqual varName 
1105 1106 1107
							(getTH_ID_SPLICE $1)))) } -- $x
	| '$(' exp ')'   	{ LL $ HsSpliceE (mkHsSplice $2) }               -- $( exp )

1108
	| TH_VAR_QUOTE qvar 	{ LL $ HsBracket (VarBr (unLoc $2)) }
1109
	| TH_VAR_QUOTE qcon 	{ LL $ HsBracket (VarBr (unLoc $2)) }
1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128
	| TH_TY_QUOTE tyvar 	{ LL $ HsBracket (VarBr (unLoc $2)) }
 	| TH_TY_QUOTE gtycon	{ LL $ HsBracket (VarBr (unLoc $2)) }
	| '[|' exp '|]'         { LL $ HsBracket (ExpBr $2) }                       
	| '[t|' ctype '|]'      { LL $ HsBracket (TypBr $2) }                       
	| '[p|' infixexp '|]'   {% checkPattern $2 >>= \p ->
					   return (LL $ HsBracket (PatBr p)) }
	| '[d|' cvtopbody '|]'	{ LL $ HsBracket (DecBr (mkGroup $2)) }

	-- arrow notation extension
	| '(|' aexp2 cmdargs '|)'	{ LL $ HsArrForm $2 Nothing (reverse $3) }

cmdargs	:: { [LHsCmdTop RdrName] }
	: cmdargs acmd			{ $2 : $1 }
  	| {- empty -}			{ [] }

acmd	:: { LHsCmdTop RdrName }
	: aexp2			{ L1 $ HsCmdTop $1 [] placeHolderType undefined }

cvtopbody :: { [LHsDecl RdrName] }
1129 1130 1131 1132 1133 1134
	:  '{'            cvtopdecls0 '}'		{ $2 }
	|      vocurly    cvtopdecls0 close		{ $2 }

cvtopdecls0 :: { [LHsDecl RdrName] }
	: {- empty -}		{ [] }
	| cvtopdecls		{ $1 }
1135

simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1136 1137 1138 1139 1140 1141
texp :: { LHsExpr RdrName }
	: exp				{ $1 }
	| qopm infixexp			{ LL $ SectionR $1 $2 }
	-- The second production is really here only for bang patterns
	-- but 

1142
texps :: { [LHsExpr RdrName] }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1143 1144
	: texps ',' texp		{ $3 : $1 }
	| texp				{ [$1] }
1145 1146 1147 1148 1149 1150 1151 1152 1153


-----------------------------------------------------------------------------
-- List expressions

-- The rules below are little bit contorted to keep lexps left-recursive while
-- avoiding another shift/reduce-conflict.

list :: { LHsExpr RdrName }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1154
	: texp			{ L1 $ ExplicitList placeHolderType [$1] }
1155
	| lexps 		{ L1 $ ExplicitList placeHolderType (reverse (unLoc $1)) }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1156 1157 1158 1159 1160
	| texp '..'		{ LL $ ArithSeq noPostTcExpr (From $1) }
	| texp ',' exp '..' 	{ LL $ ArithSeq noPostTcExpr (FromThen $1 $3) }
	| texp '..' exp	 	{ LL $ ArithSeq noPostTcExpr (FromTo $1 $3) }
	| texp ',' exp '..' exp	{ LL $ ArithSeq noPostTcExpr (FromThenTo $1 $3 $5) }
	| texp pquals		{ sL (comb2 $1 $>) $ mkHsDo ListComp (reverse (unLoc $2)) $1 }
1161 1162

lexps :: { Located [LHsExpr RdrName] }
simonpj@microsoft.com's avatar
simonpj@microsoft.com committed
1163 1164
	: lexps ',' texp 		{ LL ($3 : unLoc $1) }
	| texp ',' texp			{ LL [$3,$1] }
1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199

-----------------------------------------------------------------------------
-- List Comprehensions

pquals :: { Located [LStmt RdrName] }	-- Either a singleton ParStmt, 
					-- or a reversed list of Stmts
	: pquals1			{ case unLoc $1 of
					    [qs] -> L1 qs
					    qss  -> L1 [L1 (ParStmt stmtss)]
						 where
						    stmtss = [ (reverse qs, undefined) 
						    	     | qs <- qss ]
					}
			
pquals1 :: { Located [[LStmt RdrName]] }
	: pquals1 '|' quals		{ LL (unLoc $3 : unLoc $1) }
	| '|' quals			{ L (getLoc $2) [unLoc $2] }

quals :: { Located [LStmt RdrName] }
	: quals ',' qual		{ LL ($3 : unLoc $1) }
	| qual				{ L1 [$1] }

-----------------------------------------------------------------------------
-- Parallel array expressions

-- The rules below are little bit contorted; see the list case for details.
-- Note that, in contrast to lists, we only have finite arithmetic sequences.
-- Moreover, we allow explicit arrays with no element (represented by the nil
-- constructor in the list case).

parr :: { LHsExpr RdrName }
	: 				{ noLoc (ExplicitPArr placeHolderType []) }
	| exp				{ L1 $ ExplicitPArr placeHolderType [$1] }
	| lexps 			{ L1 $ ExplicitPArr placeHolderType 
						       (reverse (unLoc $1)) }
1200 1201 1202
	| exp '..' exp	 		{ LL $ PArrSeq noPostTcExpr (FromTo $1 $3) }
	| exp ',' exp '..' exp		{ LL $ PArrSeq noPostTcExpr (FromThenTo $1 $3 $5) }
	| exp pquals			{ sL (comb2 $1 $>) $ mkHsDo PArrComp (reverse (unLoc $2)) $1 }
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226

-- We are reusing `lexps' and `pquals' from the list case.

-----------------------------------------------------------------------------
-- Case alternatives

altslist :: { Located [LMatch RdrName] }
	: '{'            alts '}'	{ LL (reverse (unLoc $2)) }
	|     vocurly    alts  close	{ L (getLoc $2) (reverse (unLoc $2)) }

alts    :: { Located [LMatch RdrName] }
        : alts1				{ L1 (unLoc $1) }
	| ';' alts			{ LL (unLoc $2) }

alts1 	:: { Located [LMatch RdrName] }
	: alts1 ';' alt			{ LL ($3 : unLoc $1) }
	| alts1 ';'			{ LL (unLoc $1) }
	| alt				{ L1 [$1] }

alt 	:: { LMatch RdrName }
	: infixexp opt_sig alt_rhs	{%  checkPattern $1 >>= \p ->
			    		    return (LL (Match [p] $2 (unLoc $3))) }

alt_rhs :: { Located (GRHSs RdrName) }
1227
	: ralt wherebinds		{ LL (GRHSs (unLoc $1) (unLoc $2)) }
1228 1229 1230 1231 1232 1233 1234 1235 1236 1237

ralt :: { Located [LGRHS RdrName] }
	: '->' exp			{ LL (unguardedRHS $2) }
	| gdpats			{ L1 (reverse (unLoc $1)) }

gdpats :: { Located [LGRHS RdrName] }
	: gdpats gdpat			{ LL ($2 : unLoc $1) }
	| gdpat				{ L1 [$1] }

gdpat	:: { LGRHS RdrName }
1238
	: '|' quals '->' exp	 	{ sL (comb2 $1 $>) $ GRHS (reverse (unLoc $2)) $4 }
1239 1240 1241 1242 1243 1244 1245 1246 1247

-----------------------------------------------------------------------------
-- Statement sequences

stmtlist :: { Located [LStmt RdrName] }
	: '{'         	stmts '}'	{ LL (unLoc $2) }
	|     vocurly   stmts close	{ $2 }

--	do { ;; s ; s ; ; s ;; }
1248
-- The last Stmt should be an expression, but that's hard to enforce
1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269
-- here, because we need too much lookahead if we see do { e ; }
-- So we use ExprStmts throughout, and switch the last one over
-- in ParseUtils.checkDo instead
stmts :: { Located [LStmt RdrName] }
	: stmt stmts_help		{ LL ($1 : unLoc $2) }
	| ';' stmts			{ LL (unLoc $2) }
	| {- empty -}			{ noLoc [] }

stmts_help :: { Located [LStmt RdrName] } -- might be empty
	: ';' stmts			{ LL (unLoc $2) }
	| {- empty -}			{ noLoc [] }

-- For typing stmts at the GHCi prompt, where 
-- the input may consist of just comments.
maybe_stmt :: { Maybe (LStmt RdrName) }
	: stmt				{ Just $1 }
	| {- nothing -}			{ Nothing }

stmt  :: { LStmt RdrName }
	: qual				{ $1 }
	| infixexp '->' exp		{% checkPattern $3 >>= \p ->
1270 1271
					   return (LL $ mkBindStmt p $1) }
  	| 'rec' stmtlist		{ LL $ mkRecStmt (unLoc $2) }
1272 1273

qual  :: { LStmt RdrName }
1274
	: exp '<-' exp			{% checkPattern $1 >>= \p ->
1275 1276
					   return (LL $ mkBindStmt p $3) }
	| exp				{ L1 $ mkExprStmt $1 }
1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304
  	| 'let' binds			{ LL $ LetStmt (unLoc $2) }

-----------------------------------------------------------------------------
-- Record Field Update/Construction

fbinds 	:: { HsRecordBinds RdrName }
	: fbinds1			{ $1 }
  	| {- empty -}			{ [] }

fbinds1	:: { HsRecordBinds RdrName }
	: fbinds1 ',' fbind		{ $3 : $1 }
	| fbind				{ [$1] }
  
fbind	:: { (Located RdrName, LHsExpr RdrName) }
	: qvar '=' exp			{ ($1,$3) }

-----------------------------------------------------------------------------
-- Implicit Parameter Bindings

dbinds 	:: { Located [LIPBind RdrName] }
	: dbinds ';' dbind		{ LL ($3 : unLoc $1) }
	| dbinds ';'			{ LL (unLoc $1) }
	| dbind				{ L1 [$1] }
--	| {- empty -}			{ [] }

dbind	:: { LIPBind RdrName }
dbind	: ipvar '=' exp			{ LL (IPBind (unLoc $1) $3) }

1305 1306 1307
ipvar	:: { Located (IPName RdrName) }
	: IPDUPVARID		{ L1 (Dupable (mkUnqual varName (getIPDUPVARID $1))) }
	| IPSPLITVARID		{ L1 (Linear  (mkUnqual varName (getIPSPLITVARID $1))) }
1308

1309 1310
-----------------------------------------------------------------------------
-- Deprecations
1311 1312 1313 1314 1315 1316 1317

depreclist :: { Located [RdrName] }
depreclist : deprec_var			{ L1 [unLoc $1] }
	   | deprec_var ',' depreclist	{ LL (unLoc $1 : unLoc $3) }

deprec_var :: { Located RdrName }
deprec_var : var			{ $1 }
1318
	   | con			{ $1 }
1319

1320 1321
-----------------------------------------
-- Data constructors
1322 1323 1324
qcon	:: { Located RdrName }
	: qconid		{ $1 }
	| '(' qconsym ')'	{ LL (unLoc $2) }
1325 1326
	| sysdcon		{ L1 $ nameRdrName (dataConName (unLoc $1)) }
-- The case of '[:' ':]' is part of the production `parr'
1327

1328 1329 1330 1331
con	:: { Located RdrName }
	: conid			{ $1 }
	| '(' consym ')'	{ LL (unLoc $2) }
	| sysdcon		{ L1 $ nameRdrName (dataConName (unLoc $1)) }
1332

1333 1334 1335 1336
sysdcon	:: { Located DataCon }	-- Wired in data constructors
	: '(' ')'		{ LL unitDataCon }
	| '(' commas ')'	{ LL $ tupleCon Boxed $2 }
	| '[' ']'		{ LL nilDataCon }
1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379

conop :: { Located RdrName }
	: consym		{ $1 }	
	| '`' conid '`'		{ LL (unLoc $2) }

qconop :: { Located RdrName }
	: qconsym		{ $1 }
	| '`' qconid '`'	{ LL (unLoc $2) }

-----------------------------------------------------------------------------
-- Type constructors

gtycon 	:: { Located RdrName }	-- A "general" qualified tycon
	: oqtycon			{ $1 }
	| '(' ')'			{ LL $ getRdrName unitTyCon }
	| '(' commas ')'		{ LL $ getRdrName (tupleTyCon Boxed $2) }
	| '(' '->' ')'			{ LL $ getRdrName funTyCon }
	| '[' ']'			{ LL $ listTyCon_RDR }
	| '[:' ':]'			{ LL $ parrTyCon_RDR }

oqtycon :: { Located RdrName }	-- An "ordinary" qualified tycon
	: qtycon			{ $1 }
 	| '(' qtyconsym ')'		{ LL (unLoc $2) }

qtyconop :: { Located RdrName }	-- Qualified or unqualified
	: qtyconsym			{ $1 }
	| '`' qtycon '`'		{ LL (unLoc $2) }

qtycon :: { Located RdrName }	-- Qualified or unqualified
	: QCONID			{ L1 $! mkQual tcClsName (getQCONID $1) }
	| tycon				{ $1 }

tycon 	:: { Located RdrName }	-- Unqualified
	: CONID				{ L1 $! mkUnqual tcClsName (getCONID $1) }

qtyconsym :: { Located RdrName }
	: QCONSYM			{ L1 $! mkQual tcClsName (getQCONSYM $1) }
	| tyconsym			{ $1 }

tyconsym :: { Located RdrName }
	: CONSYM			{ L1 $! mkUnqual tcClsName (getCONSYM $1) }

-----------------------------------------------------------------------------
1380
-- Operators
1381 1382 1383 1384 1385

op	:: { Located RdrName }   -- used in infix decls
	: varop			{ $1 }
	| conop 		{ $1 }

1386 1387 1388 1389
varop	:: { Located RdrName }
	: varsym		{ $1 }
	| '`' varid '`'		{ LL (unLoc $2) }

1390 1391 1392 1393 1394 1395 1396 1397
qop	:: { LHsExpr RdrName }   -- used in sections
	: qvarop		{ L1 $ HsVar (unLoc $1) }
	| qconop		{ L1 $ HsVar (unLoc $1) }

qopm	:: { LHsExpr RdrName }   -- used in sections
	: qvaropm		{ L1 $ HsVar (unLoc $1) }
	| qconop		{ L1 $ HsVar (unLoc $1) }

1398 1399 1400
qvarop :: { Located RdrName }
	: qvarsym		{ $1 }
	| '`' qvarid '`'	{ LL (unLoc $2) }
1401

1402 1403 1404
qvaropm :: { Located RdrName }
	: qvarsym_no_minus	{ $1 }
	| '`' qvarid '`'	{ LL (unLoc $2) }
1405

1406 1407
-----------------------------------------------------------------------------
-- Type variables
1408

1409 1410 1411 1412 1413 1414 1415 1416 1417
tyvar   :: { Located RdrName }
tyvar   : tyvarid		{ $1 }
	| '(' tyvarsym ')'	{ LL (unLoc $2) }

tyvarop :: { Located RdrName }
tyvarop : '`' tyvarid '`'	{ LL (unLoc $2) }
	| tyvarsym		{ $1 }

tyvarid	:: { Located RdrName }
1418 1419 1420 1421 1422 1423
	: VARID			{ L1 $! mkUnqual tvName (getVARID $1) }
	| special_id		{ L1 $! mkUnqual tvName (unLoc $1) }
	| 'unsafe' 		{ L1 $! mkUnqual tvName FSLIT("unsafe") }
	| 'safe' 		{ L1 $! mkUnqual tvName FSLIT("safe") }
	| 'threadsafe' 		{ L1 $! mkUnqual tvName FSLIT("threadsafe") }

1424 1425 1426 1427 1428 1429
tyvarsym :: { Located RdrName }
-- Does not include "!", because that is used for strictness marks
--	         or ".", because that separates the quantified type vars from the rest
--		 or "*", because that's used for kinds
tyvarsym : VARSYM		{ L1 $! mkUnqual tvName (getVARSYM $1) }

1430 1431 1432
-----------------------------------------------------------------------------
-- Variables 

1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459
var 	:: { Located RdrName }
	: varid			{ $1 }
	| '(' varsym ')'	{ LL (unLoc $2) }

qvar 	:: { Located RdrName }
	: qvarid		{ $1 }
	| '(' varsym ')'	{ LL (unLoc $2) }
	| '(' qvarsym1 ')'	{ LL (unLoc $2) }
-- We've inlined qvarsym here so that the decision about
-- whether it's a qvar or a var can be postponed until
-- *after* we see the close paren.

qvarid :: { Located RdrName }
	: varid			{ $1 }
	| QVARID		{ L1 $ mkQual varName (getQVARID $1) }

varid :: { Located RdrName }
	: varid_no_unsafe 	{ $1 }
	| 'unsafe'		{ L1 $! mkUnqual varName FSLIT("unsafe") }
	| 'safe'		{ L1 $! mkUnqual varName FSLIT("safe") }
	| 'threadsafe'		{ L1 $! mkUnqual varName FSLIT("threadsafe") }

varid_no_unsafe :: { Located RdrName }
	: VARID			{ L1 $! mkUnqual varName (getVARID $1) }
	| special_id		{ L1 $! mkUnqual varName (unLoc $1) }
	| 'forall'		{ L1 $! mkUnqual varName FSLIT("forall") }

1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479
qvarsym :: { Located RdrName }
	: varsym		{ $1 }
	| qvarsym1		{ $1 }

qvarsym_no_minus :: { Located RdrName }
	: varsym_no_minus	{ $1 }
	| qvarsym1		{ $1 }

qvarsym1 :: { Located RdrName }
qvarsym1 : QVARSYM		{ L1 $ mkQual varName (getQVARSYM $1) }

varsym :: { Located RdrName }
	: varsym_no_minus 	{ $1 }
	| '-'			{ L1 $ mkUnqual varName FSLIT("-") }

varsym_no_minus :: { Located RdrName } -- varsym not including '-'
	: VARSYM		{ L1 $ mkUnqual varName (getVARSYM $1) }
	| special_sym		{ L1 $ mkUnqual varName (unLoc $1) }


1480 1481 1482
-- These special_ids are treated as keywords in various places, 
-- but as ordinary ids elsewhere.   'special_id' collects all these
-- except 'unsafe' and 'forall' whose treatment differs depending on context
1483
special_id :: { Located FastString }
1484 1485 1486 1487 1488 1489 1490 1491 1492 1493
special_id
	: 'as'			{ L1 FSLIT("as") }
	| 'qualified'		{ L1 FSLIT("qualified") }
	| 'hiding'		{ L1 FSLIT("hiding") }
	| 'export'		{ L1 FSLIT("export") }
	| 'label'		{ L1 FSLIT("label")  }
	| 'dynamic'		{ L1 FSLIT("dynamic") }
	| 'stdcall'             { L1 FSLIT("stdcall") }
	| 'ccall'               { L1 FSLIT("ccall") }

1494
special_sym :: { Located FastString }
1495 1496 1497 1498 1499 1500 1501
special_sym : '!'	{ L1 FSLIT("!") }
	    | '.' 	{ L1 FSLIT(".") }
 	    | '*' 	{ L1 FSLIT("*") }

-----------------------------------------------------------------------------
-- Data constructors

1502
qconid :: { Located RdrName }	-- Qualified or unqualified
1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541
	: conid			{ $1 }
	| QCONID		{ L1 $ mkQual dataName (getQCONID $1) }

conid 	:: { Located RdrName }
	: CONID			{ L1 $ mkUnqual dataName (getCONID $1) }

qconsym :: { Located RdrName }	-- Qualified or unqualified
	: consym		{ $1 }
	| QCONSYM		{ L1 $ mkQual dataName (getQCONSYM $1) }

consym :: { Located RdrName }
	: CONSYM		{ L1 $ mkUnqual dataName (getCONSYM $1) }

	-- ':' means only list cons
	| ':'			{ L1 $ consDataCon_RDR }


-----------------------------------------------------------------------------
-- Literals

literal :: { Located HsLit }
	: CHAR 			{ L1 $ HsChar       $ getCHAR $1 }
	| STRING		{ L1 $ HsString     $ getSTRING $1 }
	| PRIMINTEGER		{ L1 $ HsIntPrim    $ getPRIMINTEGER $1 }
	| PRIMCHAR		{ L1 $ HsCharPrim   $ getPRIMCHAR $1 }
	| PRIMSTRING		{ L1 $ HsStringPrim $ getPRIMSTRING $1 }
	| PRIMFLOAT		{ L1 $ HsFloatPrim  $ getPRIMFLOAT $1 }
	| PRIMDOUBLE		{ L1 $ HsDoublePrim $ getPRIMDOUBLE $1 }

-----------------------------------------------------------------------------
-- Layout

close :: { () }
	: vccurly		{ () } -- context popped in lexer.
	| error			{% popContext }

-----------------------------------------------------------------------------
-- Miscellaneous (mostly renamings)

1542 1543
modid 	:: { Located Module }
	: CONID			{ L1 $ mkModuleFS (getCONID $1) }
1544
        | QCONID		{ L1 $ let (mod,c) = getQCONID $1 in
1545
				  mkModuleFS
1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579
				   (mkFastString
				     (unpackFS mod ++ '.':unpackFS c))
				}

commas :: { Int }
	: commas ','			{ $1 + 1 }
	| ','				{ 2 }

-----------------------------------------------------------------------------

{
happyError :: P a
happyError = srcParseFail

getVARID   	(L _ (ITvarid    x)) = x
getCONID   	(L _ (ITconid    x)) = x
getVARSYM  	(L _ (ITvarsym   x)) = x
getCONSYM  	(L _ (ITconsym   x)) = x
getQVARID  	(L _ (ITqvarid   x)) = x
getQCONID  	(L _ (ITqconid   x)) = x
getQVARSYM 	(L _ (ITqvarsym  x)) = x
getQCONSYM 	(L _ (ITqconsym  x)) = x
getIPDUPVARID   (L _ (ITdupipvarid   x)) = x
getIPSPLITVARID (L _ (ITsplitipvarid x)) = x
getCHAR		(L _ (ITchar     x)) = x
getSTRING	(L _ (ITstring   x)) = x
getINTEGER	(L _ (ITinteger  x)) = x
getRATIONAL	(L _ (ITrational x)) = x
getPRIMCHAR	(L _ (ITprimchar   x)) = x
getPRIMSTRING	(L _ (ITprimstring x)) = x
getPRIMINTEGER	(L _ (ITprimint    x)) = x
getPRIMFLOAT	(L _ (ITprimfloat  x)) = x
getPRIMDOUBLE	(L _ (ITprimdouble x)) = x
getTH_ID_SPLICE (L _ (ITidEscape x)) = x
1580 1581
getINLINE	(L _ (ITinline_prag b)) = b
getSPEC_INLINE	(L _ (ITspec_inline_prag b)) = b
1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598

-- Utilities for combining source spans
comb2 :: Located a -> Located b -> SrcSpan
comb2 = combineLocs

comb3 :: Located a -> Located b -> Located c -> SrcSpan
comb3 a b c = combineSrcSpans (getLoc a) (combineSrcSpans (getLoc b) (getLoc c))

comb4 :: Located a -> Located b -> Located c -> Located d -> SrcSpan
comb4 a b c d = combineSrcSpans (getLoc a) $ combineSrcSpans (getLoc b) $
		combineSrcSpans (getLoc c) (getLoc d)

-- strict constructor version:
{-# INLINE sL #-}
sL :: SrcSpan -> a -> Located a
sL span a = span `seq` L span a

1599 1600 1601
-- Make a source location for the file.  We're a bit lazy here and just
-- make a point SrcSpan at line 1, column 0.  Strictly speaking we should
-- try to find the span of the whole file (ToDo).
1602
fileSrcSpan :: P SrcSpan
1603 1604 1605 1606
fileSrcSpan = do 
  l <- getSrcLoc; 
  let loc = mkSrcLoc (srcLocFile l) 1 0;
  return (mkSrcSpan loc loc)
1607
}