Parser.y.pp 96.2 KB
Newer Older
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
1
--                                                              -*-haskell-*-
2
3
4
5
6
7
8
9
10
-- ---------------------------------------------------------------------------
-- (c) The University of Glasgow 1997-2003
---
-- The GHC grammar.
--
-- Author(s): Simon Marlow, Sven Panne 1997, 1998, 1999
-- ---------------------------------------------------------------------------

{
11
{-# LANGUAGE BangPatterns #-} -- required for versions of Happy before 1.18.6
12
{-# OPTIONS -Wwarn -w #-}
13
14
15
16
17
18
-- The above warning supression flag is a temporary kludge.
-- While working on this module you are encouraged to remove it and fix
-- any warnings in the module. See
--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
-- for details

19
20
21
22
23
24
25
26
{-# OPTIONS_GHC -O0 -fno-ignore-interface-pragmas #-}
{-
Careful optimisation of the parser: we don't want to throw everything
at it, because that takes too long and doesn't buy much, but we do want
to inline certain key external functions, so we instruct GHC not to
throw away inlinings as it would normally do in -O0 mode.
-}

27
28
29
30
31
32
33
34
35
36
-- CPP tricks because we want the directives in the output of the
-- first CPP pass.
#define __IF_GHC_77__ #if __GLASGOW_HASKELL__ >= 707
#define __ENDIF__     #endif
__IF_GHC_77__
-- Required on x86 to avoid the register allocator running out of
-- stack slots when compiling this module with -fPIC -dynamic.
{-# OPTIONS_GHC -fcmm-sink #-}
__ENDIF__

37
module Parser ( parseModule, parseStmt, parseIdentifier, parseType,
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
38
                parseHeader ) where
39
40
41

import HsSyn
import RdrHsSyn
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
42
import HscTypes         ( IsBootInterface, WarningTxt(..) )
43
44
import Lexer
import RdrName
45
import TcEvidence       ( emptyTcEvBinds )
dreixel's avatar
dreixel committed
46
import TysPrim          ( liftedTypeKindTyConName, eqPrimTyCon )
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
47
import TysWiredIn       ( unitTyCon, unitDataCon, tupleTyCon, tupleCon, nilDataCon,
48
                          unboxedUnitTyCon, unboxedUnitDataCon,
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
49
50
                          listTyCon_RDR, parrTyCon_RDR, consDataCon_RDR, eqTyCon_RDR )
import Type             ( funTyCon )
51
import ForeignCall
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
52
53
import OccName          ( varName, dataName, tcClsName, tvName )
import DataCon          ( DataCon, dataConName )
Ian Lynagh's avatar
Ian Lynagh committed
54
import SrcLoc
55
import Module
dreixel's avatar
dreixel committed
56
import Kind             ( Kind, liftedTypeKind, unliftedTypeKind, mkArrowKind )
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
57
import Class            ( FunDep )
58
import BasicTypes
59
import DynFlags
60
import OrdList
61
import HaddockUtils
62
63

import FastString
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
64
import Maybes           ( orElse )
65
import Outputable
66

67
import Control.Monad    ( unless, liftM )
Simon Marlow's avatar
Simon Marlow committed
68
import GHC.Exts
69
70
import Data.Char
import Control.Monad    ( mplus )
71
72
73
}

{-
74
-----------------------------------------------------------------------------
Gabor Greif's avatar
Gabor Greif committed
75
76
77
78
79
80
81
12 October 2012

Conflicts: 43 shift/reduce
           1 reduce/reduce

-----------------------------------------------------------------------------
24 February 2006
82
83
84
85
86
87
88
89
90

Conflicts: 33 shift/reduce
           1 reduce/reduce

The reduce/reduce conflict is weird.  It's between tyconsym and consym, and I
would think the two should never occur in the same context.

  -=chak

91
92
93
94
95
96
97
98
99
100
101
-----------------------------------------------------------------------------
31 December 2006

Conflicts: 34 shift/reduce
           1 reduce/reduce

The reduce/reduce conflict is weird.  It's between tyconsym and consym, and I
would think the two should never occur in the same context.

  -=chak

102
103
104
105
106
107
108
109
110
111
112
-----------------------------------------------------------------------------
6 December 2006

Conflicts: 32 shift/reduce
           1 reduce/reduce

The reduce/reduce conflict is weird.  It's between tyconsym and consym, and I
would think the two should never occur in the same context.

  -=chak

113
114
115
116
117
118
119
120
121
122
123
-----------------------------------------------------------------------------
26 July 2006

Conflicts: 37 shift/reduce
           1 reduce/reduce

The reduce/reduce conflict is weird.  It's between tyconsym and consym, and I
would think the two should never occur in the same context.

  -=chak

124
-----------------------------------------------------------------------------
125
Conflicts: 38 shift/reduce (1.25)
126

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
127
128
129
10 for abiguity in 'if x then y else z + 1'             [State 178]
        (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
130

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
131
132
1 for ambiguity in 'if x then y else z :: T'            [State 178]
        (shift parses as 'if x then y else (z :: T)', as per longest-parse rule)
133

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
134
135
136
4 for ambiguity in 'if x then y else z -< e'            [State 178]
        (shift parses as 'if x then y else (z -< T)', as per longest-parse rule)
        There are four such operators: -<, >-, -<<, >>-
137
138


chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
139
140
141
142
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
143
    or
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
144
145
          case v of
            (x::T -> T) -> ..   -- Rhs is ...
ross's avatar
ross committed
146

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
147
148
149
10 for ambiguity in 'e :: a `b` c'.  Does this mean     [States 11, 253]
        (e::a) `b` c, or 
        (e :: (a `b` c))
150
    As well as `b` we can have !, VARSYM, QCONSYM, and CONSYM, hence 5 cases
151
    Same duplication between states 11 and 253 as the previous case
152

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
153
154
155
156
1 for ambiguity in 'let ?x ...'                         [State 329]
        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.
157

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
158
159
160
161
1 for ambiguity in '{-# RULES "name" [ ... #-}          [State 382]
        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
162

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
163
164
165
166
167
168
169
1 for ambiguity in '{-# RULES "name" forall = ... #-}'  [State 474]
        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'.
170

171
172
173
174
1 for ambiguity when the source file starts with "-- | doc". We need another
  token of lookahead to determine if a top declaration or the 'module' keyword
  follows. Shift parses as if the 'module' keyword follows.   

175
176
177
178
179
180
181
182
183
184
-- ---------------------------------------------------------------------------
-- 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.

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
185
   L0   adds 'noSrcSpan', used for empty productions
186
     -- This doesn't seem to work anymore -=chak
187
188

   L1   for a production with a single token on the lhs.  Grabs the SrcSpan
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
189
        from that token.
190
191
192
193
194
195
196
197
198

   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.

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
199
200
201
        | 'newtype' tycl_hdr '=' newconstr deriving
                { L (comb3 $1 $4 $5)
                    (mkTyData NewType (unLoc $2) [$4] (unLoc $5)) }
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221

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
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
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
 '_'            { 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 }
255
 'interruptible' { L _ ITinterruptible }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
256
257
258
 'unsafe'       { L _ ITunsafe }
 'mdo'          { L _ ITmdo }
 'family'       { L _ ITfamily }
259
260
 'stdcall'      { L _ ITstdcallconv }
 'ccall'        { L _ ITccallconv }
261
 'capi'         { L _ ITcapiconv }
262
 'prim'         { L _ ITprimcallconv }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
263
264
 'proc'         { L _ ITproc }          -- for arrow notation extension
 'rec'          { L _ ITrec }           -- for arrow notation extension
265
266
267
 'group'    { L _ ITgroup }     -- for list transform extension
 'by'       { L _ ITby }        -- for list transform extension
 'using'    { L _ ITusing }     -- for list transform extension
268

269
270
 '{-# INLINE'             { L _ (ITinline_prag _ _) }
 '{-# SPECIALISE'         { L _ ITspec_prag }
271
 '{-# SPECIALISE_INLINE'  { L _ (ITspec_inline_prag _) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
272
273
274
 '{-# SOURCE'                                   { L _ ITsource_prag }
 '{-# RULES'                                    { L _ ITrules_prag }
 '{-# CORE'                                     { L _ ITcore_prag }              -- hdaume: annotated core
275
276
277
278
279
 '{-# SCC'                { L _ ITscc_prag }
 '{-# GENERATED'          { L _ ITgenerated_prag }
 '{-# DEPRECATED'         { L _ ITdeprecated_prag }
 '{-# WARNING'            { L _ ITwarning_prag }
 '{-# UNPACK'             { L _ ITunpack_prag }
280
 '{-# NOUNPACK'           { L _ ITnounpack_prag }
281
 '{-# ANN'                { L _ ITann_prag }
282
283
 '{-# VECTORISE'          { L _ ITvect_prag }
 '{-# VECTORISE_SCALAR'   { L _ ITvect_scalar_prag }
284
 '{-# NOVECTORISE'        { L _ ITnovect_prag }
285
 '{-# CTYPE'              { L _ ITctype }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
286
287
288
289
290
291
292
 '#-}'                                          { L _ ITclose_prag }

 '..'           { L _ ITdotdot }                        -- reserved symbols
 ':'            { L _ ITcolon }
 '::'           { L _ ITdcolon }
 '='            { L _ ITequal }
 '\\'           { L _ ITlam }
293
 'lcase'        { L _ ITlcase }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
 '|'            { L _ ITvbar }
 '<-'           { L _ ITlarrow }
 '->'           { L _ ITrarrow }
 '@'            { L _ ITat }
 '~'            { L _ ITtilde }
 '~#'           { L _ ITtildehsh }
 '=>'           { 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 }
 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 }
dreixel's avatar
dreixel committed
327
 SIMPLEQUOTE    { L _ ITsimpleQuote      }     -- 'x
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
328
329
330
331
332
333
334
335
336

 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  _) }
337
338
 PREFIXQVARSYM  { L _ (ITprefixqvarsym  _) }
 PREFIXQCONSYM  { L _ (ITprefixqconsym  _) }
339

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
 IPDUPVARID     { L _ (ITdupipvarid   _) }              -- GHC extension

 CHAR           { L _ (ITchar     _) }
 STRING         { L _ (ITstring   _) }
 INTEGER        { L _ (ITinteger  _) }
 RATIONAL       { L _ (ITrational _) }
                    
 PRIMCHAR       { L _ (ITprimchar   _) }
 PRIMSTRING     { L _ (ITprimstring _) }
 PRIMINTEGER    { L _ (ITprimint    _) }
 PRIMWORD       { L _ (ITprimword  _) }
 PRIMFLOAT      { L _ (ITprimfloat  _) }
 PRIMDOUBLE     { L _ (ITprimdouble _) }

 DOCNEXT        { L _ (ITdocCommentNext _) }
 DOCPREV        { L _ (ITdocCommentPrev _) }
 DOCNAMED       { L _ (ITdocCommentNamed _) }
 DOCSECTION     { L _ (ITdocSection _ _) }
358

359
360
361
362
363
364
365
-- Template Haskell 
'[|'            { L _ ITopenExpQuote  }       
'[p|'           { L _ ITopenPatQuote  }      
'[t|'           { L _ ITopenTypQuote  }      
'[d|'           { L _ ITopenDecQuote  }      
'|]'            { L _ ITcloseQuote    }
TH_ID_SPLICE    { L _ (ITidEscape _)  }     -- $x
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
366
367
368
'$('            { L _ ITparenEscape   }     -- $( exp )
TH_TY_QUOTE     { L _ ITtyQuote       }      -- ''T
TH_QUASIQUOTE   { L _ (ITquasiQuote _) }
369
TH_QQUASIQUOTE  { L _ (ITqQuasiQuote _) }
370
371
372
373
374
375

%monad { P } { >>= } { return }
%lexer { lexer } { L _ ITeof }
%name parseModule module
%name parseStmt   maybe_stmt
%name parseIdentifier  identifier
376
%name parseType ctype
377
%partial parseHeader header
378
%tokentype { (Located Token) }
379
380
%%

381
382
383
-----------------------------------------------------------------------------
-- Identifiers; one of the entry points
identifier :: { Located RdrName }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
384
385
386
387
        : qvar                          { $1 }
        | qcon                          { $1 }
        | qvarop                        { $1 }
        | qconop                        { $1 }
388
    | '(' '->' ')'      { LL $ getRdrName funTyCon }
389

390
391
392
393
394
395
396
397
398
399
-----------------------------------------------------------------------------
-- 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. :-)

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
400
401
402
403
module  :: { Located (HsModule RdrName) }
        : maybedocheader 'module' modid maybemodwarning maybeexports 'where' body
                {% fileSrcSpan >>= \ loc ->
                   return (L loc (HsModule (Just $3) $5 (fst $7) (snd $7) $4 $1
404
                          ) )}
405
        | body2
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
406
407
                {% fileSrcSpan >>= \ loc ->
                   return (L loc (HsModule Nothing Nothing
408
409
                          (fst $1) (snd $1) Nothing Nothing
                          )) }
410

411
maybedocheader :: { Maybe LHsDocString }
412
        : moduleheader            { $1 }
413
        | {- empty -}             { Nothing }
414
415

missing_module_keyword :: { () }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
416
        : {- empty -}                           {% pushCurrentContext }
417

Ian Lynagh's avatar
Ian Lynagh committed
418
maybemodwarning :: { Maybe WarningTxt }
419
420
    : '{-# DEPRECATED' strings '#-}' { Just (DeprecatedTxt $ unLoc $2) }
    | '{-# WARNING' strings '#-}'    { Just (WarningTxt $ unLoc $2) }
Ian Lynagh's avatar
Ian Lynagh committed
421
    |  {- empty -}                  { Nothing }
422

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
423
424
425
body    :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
        :  '{'            top '}'               { $2 }
        |      vocurly    top close             { $2 }
426

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
427
428
429
body2   :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
        :  '{' top '}'                          { $2 }
        |  missing_module_keyword top close     { $2 }
430

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
431
432
433
434
top     :: { ([LImportDecl RdrName], [LHsDecl RdrName]) }
        : importdecls                           { (reverse $1,[]) }
        | importdecls ';' cvtopdecls            { (reverse $1,$3) }
        | cvtopdecls                            { ([],$1) }
435
436

cvtopdecls :: { [LHsDecl RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
437
        : topdecls                              { cvTopDecls $1 }
438

439
440
441
-----------------------------------------------------------------------------
-- Module declaration & imports only

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
442
443
444
445
header  :: { Located (HsModule RdrName) }
        : maybedocheader 'module' modid maybemodwarning maybeexports 'where' header_body
                {% fileSrcSpan >>= \ loc ->
                   return (L loc (HsModule (Just $3) $5 $7 [] $4 $1
446
                          ))}
447
        | header_body2
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
448
                {% fileSrcSpan >>= \ loc ->
449
                   return (L loc (HsModule Nothing Nothing $1 [] Nothing
450
                          Nothing)) }
451
452

header_body :: { [LImportDecl RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
453
        :  '{'            importdecls           { $2 }
454
455
456
457
458
        |      vocurly    importdecls           { $2 }

header_body2 :: { [LImportDecl RdrName] }
        :  '{' importdecls                      { $2 }
        |  missing_module_keyword importdecls   { $2 }
459

460
461
462
463
-----------------------------------------------------------------------------
-- The Export List

maybeexports :: { Maybe [LIE RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
464
465
        :  '(' exportlist ')'                   { Just $2 }
        |  {- empty -}                          { Nothing }
466

467
exportlist :: { [LIE RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
468
469
        : expdoclist ',' expdoclist             { $1 ++ $3 }
        | exportlist1                           { $1 }
470
471

exportlist1 :: { [LIE RdrName] }
472
        : expdoclist export expdoclist ',' exportlist  { $1 ++ ($2 : $3) ++ $5 }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
473
474
        | expdoclist export expdoclist                 { $1 ++ ($2 : $3) }
        | expdoclist                                   { $1 }
475
476
477
478
479
480
481
482
483

expdoclist :: { [LIE RdrName] }
        : exp_doc expdoclist                           { $1 : $2 }
        | {- empty -}                                  { [] }

exp_doc :: { LIE RdrName }                                                   
        : docsection    { L1 (case (unLoc $1) of (n, doc) -> IEGroup n doc) }
        | docnamed      { L1 (IEDocNamed ((fst . unLoc) $1)) } 
        | docnext       { L1 (IEDoc (unLoc $1)) }       
484
485


486
487
   -- No longer allow things like [] and (,,,) to be exported
   -- They are built in syntax, always available
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
488
export  :: { LIE RdrName }
489
490
        : qcname_ext export_subspec     { LL (mkModuleImpExp (unLoc $1)
                                                             (unLoc $2)) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
491
        |  'module' modid               { LL (IEModuleContents (unLoc $2)) }
492

493
494
495
496
export_subspec :: { Located ImpExpSubSpec }
        : {- empty -}                   { L0 ImpExpAbs }
        | '(' '..' ')'                  { LL ImpExpAll }
        | '(' ')'                       { LL (ImpExpList []) }
497
        | '(' qcnames ')'               { LL (ImpExpList (reverse $2)) }
498

499
qcnames :: { [RdrName] }     -- A reversed list
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
500
501
        :  qcnames ',' qcname_ext       { unLoc $3 : $1 }
        |  qcname_ext                   { [unLoc $1]  }
502

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
503
504
505
qcname_ext :: { Located RdrName }       -- Variable or data constructor
                                        -- or tagged type constructor
        :  qcname                       { $1 }
506
        |  'type' qcname                {% mkTypeImpExp (LL (unLoc $2)) }
507
508

-- Cannot pull into qcname_ext, as qcname is also used in expression.
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
509
510
511
qcname  :: { Located RdrName }  -- Variable or data constructor
        :  qvar                         { $1 }
        |  qcon                         { $1 }
512
513
514
515
516
517
518
519

-----------------------------------------------------------------------------
-- 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] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
520
521
522
523
        : importdecls ';' importdecl            { $3 : $1 }
        | importdecls ';'                       { $1 }
        | importdecl                            { [ $1 ] }
        | {- empty -}                           { [] }
524
525

importdecl :: { LImportDecl RdrName }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
526
527
        : 'import' maybe_src maybe_safe optqualified maybe_pkg modid maybeas maybeimpspec 
                { L (comb4 $1 $6 $7 $8) $
528
529
530
531
                  ImportDecl { ideclName = $6, ideclPkgQual = $5
                             , ideclSource = $2, ideclSafe = $3
                             , ideclQualified = $4, ideclImplicit = False
                             , ideclAs = unLoc $7, ideclHiding = unLoc $8 } }
532
533

maybe_src :: { IsBootInterface }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
534
535
        : '{-# SOURCE' '#-}'                    { True }
        | {- empty -}                           { False }
536

537
maybe_safe :: { Bool }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
538
539
        : 'safe'                                { True }
        | {- empty -}                           { False }
540

541
542
543
544
maybe_pkg :: { Maybe FastString }
        : STRING                                { Just (getSTRING $1) }
        | {- empty -}                           { Nothing }

545
optqualified :: { Bool }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
546
547
        : 'qualified'                           { True  }
        | {- empty -}                           { False }
548

Simon Marlow's avatar
Simon Marlow committed
549
maybeas :: { Located (Maybe ModuleName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
550
551
        : 'as' modid                            { LL (Just (unLoc $2)) }
        | {- empty -}                           { noLoc Nothing }
552
553

maybeimpspec :: { Located (Maybe (Bool, [LIE RdrName])) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
554
555
        : impspec                               { L1 (Just (unLoc $1)) }
        | {- empty -}                           { noLoc Nothing }
556
557

impspec :: { Located (Bool, [LIE RdrName]) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
558
559
        :  '(' exportlist ')'                   { LL (False, $2) }
        |  'hiding' '(' exportlist ')'          { LL (True,  $3) }
560
561
562
563

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

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
564
565
566
prec    :: { Int }
        : {- empty -}           { 9 }
        | INTEGER               {% checkPrecP (L1 (fromInteger (getINTEGER $1))) }
567

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
568
569
570
571
infix   :: { Located FixityDirection }
        : 'infix'                               { L1 InfixN  }
        | 'infixl'                              { L1 InfixL  }
        | 'infixr'                              { L1 InfixR }
572

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
573
574
575
ops     :: { Located [Located RdrName] }
        : ops ',' op                            { LL ($3 : unLoc $1) }
        | op                                    { L1 [$1] }
576
577
578
579

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

580
topdecls :: { OrdList (LHsDecl RdrName) }
581
582
583
        : topdecls ';' topdecl                  { $1 `appOL` $3 }
        | topdecls ';'                          { $1 }
        | topdecl                               { $1 }
584

585
topdecl :: { OrdList (LHsDecl RdrName) }
586
587
        : cl_decl                               { unitOL (L1 (TyClD (unLoc $1))) }
        | ty_decl                               { unitOL (L1 (TyClD (unLoc $1))) }
588
        | inst_decl                             { unitOL (L1 (InstD (unLoc $1))) }
589
        | stand_alone_deriving                  { unitOL (LL (DerivD (unLoc $1))) }
590
591
        | 'default' '(' comma_types0 ')'        { unitOL (LL $ DefD (DefaultDecl $3)) }
        | 'foreign' fdecl                       { unitOL (LL (unLoc $2)) }
592
593
        | '{-# DEPRECATED' deprecations '#-}'   { $2 }
        | '{-# WARNING' warnings '#-}'          { $2 }
594
        | '{-# RULES' rules '#-}'               { $2 }
595
596
597
        | '{-# VECTORISE_SCALAR' qvar '#-}'     { unitOL $ LL $ VectD (HsVect       $2 Nothing) }
        | '{-# VECTORISE' qvar '=' exp '#-}'    { unitOL $ LL $ VectD (HsVect       $2 (Just $4)) }
        | '{-# NOVECTORISE' qvar '#-}'          { unitOL $ LL $ VectD (HsNoVect     $2) }
598
599
600
601
602
603
604
605
606
        | '{-# VECTORISE' 'type' gtycon '#-}'     
                                                { unitOL $ LL $ 
                                                    VectD (HsVectTypeIn False $3 Nothing) }
        | '{-# VECTORISE_SCALAR' 'type' gtycon '#-}'     
                                                { unitOL $ LL $ 
                                                    VectD (HsVectTypeIn True $3 Nothing) }
        | '{-# VECTORISE' 'type' gtycon '=' gtycon '#-}'     
                                                { unitOL $ LL $ 
                                                    VectD (HsVectTypeIn False $3 (Just $5)) }
607
608
609
        | '{-# VECTORISE_SCALAR' 'type' gtycon '=' gtycon '#-}'     
                                                { unitOL $ LL $ 
                                                    VectD (HsVectTypeIn True $3 (Just $5)) }
610
611
        | '{-# VECTORISE' 'class' gtycon '#-}'  { unitOL $ LL $ VectD (HsVectClassIn $3) }
        | '{-# VECTORISE_SCALAR' 'instance' type '#-}'     
612
                                                { unitOL $ LL $ VectD (HsVectInstIn $3) }
613
614
615
616
617
618
619
620
        | annotation { unitOL $1 }
        | decl                                  { unLoc $1 }

        -- Template Haskell Extension
        -- The $(..) form is one possible form of infixexp
        -- but we treat an arbitrary expression just as if 
        -- it had a $(..) wrapped around it
        | infixexp                              { unitOL (LL $ mkTopSpliceDecl $1) } 
621

622
623
624
-- Type classes
--
cl_decl :: { LTyClDecl RdrName }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
625
        : 'class' tycl_hdr fds where_cls        {% mkClassDecl (comb4 $1 $2 $3 $4) $2 $3 $4 }
626

627
-- Type declarations (toplevel)
628
629
--
ty_decl :: { LTyClDecl RdrName }
630
           -- ordinary type synonyms
631
        : 'type' type '=' ctypedoc
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
632
633
634
635
636
637
638
                -- Note ctype, not sigtype, on the right of '='
                -- 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
                --
                -- Note the use of type for the head; this allows
                -- infix type constructors to be declared 
639
                {% mkTySynonym (comb2 $1 $4) $2 $4 }
640
641

           -- type family declarations
642
        | 'type' 'family' type opt_kind_sig 
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
643
644
645
                -- Note the use of type for the head; this allows
                -- infix type constructors to be declared
                {% mkTyFamily (comb3 $1 $3 $4) TypeFamily $3 (unLoc $4) }
646

647
          -- ordinary data type or newtype declaration
648
        | data_or_newtype capi_ctype tycl_hdr constrs deriving
649
                {% mkTyData (comb4 $1 $3 $4 $5) (unLoc $1) $2 $3 
650
                            Nothing (reverse (unLoc $4)) (unLoc $5) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
651
652
                                   -- We need the location on tycl_hdr in case 
                                   -- constrs and deriving are both empty
653

654
          -- ordinary GADT declaration
655
        | data_or_newtype capi_ctype tycl_hdr opt_kind_sig 
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
656
657
                 gadt_constrlist
                 deriving
658
                {% mkTyData (comb4 $1 $3 $5 $6) (unLoc $1) $2 $3 
659
                            (unLoc $4) (unLoc $5) (unLoc $6) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
660
661
                                   -- We need the location on tycl_hdr in case 
                                   -- constrs and deriving are both empty
662

663
          -- data/newtype family
664
        | 'data' 'family' type opt_kind_sig
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
665
                {% mkTyFamily (comb3 $1 $2 $4) DataFamily $3 (unLoc $4) }
666

667
668
inst_decl :: { LInstDecl RdrName }
        : 'instance' inst_type where_inst
669
                 { let (binds, sigs, _, ats, _) = cvBindsAndSigs (unLoc $3)
670
                   in L (comb3 $1 $2 $3) (ClsInstD { cid_poly_ty = $2, cid_binds = binds
671
                                                   , cid_sigs = sigs, cid_fam_insts = ats }) }
672
673

           -- type instance declarations
674
        | 'type' 'instance' type '=' ctype
675
676
                -- Note the use of type for the head; this allows
                -- infix type constructors and type patterns
677
                {% do { L loc d <- mkFamInstSynonym (comb2 $1 $5) $3 $5
678
                      ; return (L loc (FamInstD { lid_inst = d })) } }
679

680
          -- data/newtype instance declaration
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
681
        | data_or_newtype 'instance' tycl_hdr constrs deriving
682
                {% do { L loc d <- mkFamInstData (comb4 $1 $3 $4 $5) (unLoc $1) Nothing $3
683
                                      Nothing (reverse (unLoc $4)) (unLoc $5)
684
                      ; return (L loc (FamInstD { lid_inst = d })) } }
685

686
          -- GADT instance declaration
687
        | data_or_newtype 'instance' tycl_hdr opt_kind_sig 
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
688
689
                 gadt_constrlist
                 deriving
690
                {% do { L loc d <- mkFamInstData (comb4 $1 $3 $5 $6) (unLoc $1) Nothing $3
691
                                            (unLoc $4) (unLoc $5) (unLoc $6)
692
                      ; return (L loc (FamInstD { lid_inst = d })) } }
693
        
694
-- Associated type family declarations
695
696
697
698
699
700
701
--
-- * They have a different syntax than on the toplevel (no family special
--   identifier).
--
-- * They also need to be separate from instances; otherwise, data family
--   declarations without a kind signature cause parsing conflicts with empty
--   data declarations. 
702
--
703
704
at_decl_cls :: { LHsDecl RdrName }
           -- family declarations
705
        : 'type' type opt_kind_sig
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
706
                -- Note the use of type for the head; this allows
707
                -- infix type constructors to be declared.
708
709
710
711
712
713
                {% do { L loc decl <- mkTyFamily (comb3 $1 $2 $3) TypeFamily $2 (unLoc $3)
                      ; return (L loc (TyClD decl)) } }

        | 'data' type opt_kind_sig
                {% do { L loc decl <- mkTyFamily (comb3 $1 $2 $3) DataFamily $2 (unLoc $3)
                      ; return (L loc (TyClD decl)) } }
714

715
           -- default type instance
716
        | 'type' type '=' ctype
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
717
718
                -- Note the use of type for the head; this allows
                -- infix type constructors and type patterns
719
                {% do { L loc fid <- mkFamInstSynonym (comb2 $1 $4) $2 $4
720
                      ; return (L loc (InstD (FamInstD { lid_inst = fid }))) } }
721
722

-- Associated type instances
723
--
724
at_decl_inst :: { LFamInstDecl RdrName }
725
           -- type instance declarations
726
        : 'type' type '=' ctype
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
727
728
                -- Note the use of type for the head; this allows
                -- infix type constructors and type patterns
729
                {% mkFamInstSynonym (comb2 $1 $4) $2 $4 }
730
731

        -- data/newtype instance declaration
732
        | data_or_newtype capi_ctype tycl_hdr constrs deriving
733
734
                {% mkFamInstData (comb4 $1 $3 $4 $5) (unLoc $1) $2 $3 
                                 Nothing (reverse (unLoc $4)) (unLoc $5) }
735
736

        -- GADT instance declaration
737
        | data_or_newtype capi_ctype tycl_hdr opt_kind_sig 
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
738
739
                 gadt_constrlist
                 deriving
740
741
                {% mkFamInstData (comb4 $1 $3 $5 $6) (unLoc $1) $2 $3 
                                 (unLoc $4) (unLoc $5) (unLoc $6) }
742

743
data_or_newtype :: { Located NewOrData }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
744
745
        : 'data'        { L1 DataType }
        | 'newtype'     { L1 NewType }
746

747
opt_kind_sig :: { Located (Maybe (LHsKind RdrName)) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
748
        :                               { noLoc Nothing }
749
        | '::' kind                     { LL (Just $2) }
750

751
-- tycl_hdr parses the header of a class or data type decl,
752
-- which takes the form
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
753
754
755
756
--      T a b
--      Eq a => T a
--      (Eq a, Ord b) => T a b
--      T Int [a]                       -- for associated types
757
-- Rather a lot of inlining here, else we get reduce/reduce errors
758
tycl_hdr :: { Located (Maybe (LHsContext RdrName), LHsType RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
759
760
        : context '=>' type             { LL (Just $1, $3) }
        | type                          { L1 (Nothing, $1) }
761

762
capi_ctype :: { Maybe CType }
763
764
capi_ctype : '{-# CTYPE' STRING STRING '#-}' { Just (CType (Just (Header (getSTRING $2))) (getSTRING $3)) }
           | '{-# CTYPE'        STRING '#-}' { Just (CType Nothing                        (getSTRING $2)) }
765
           |                                 { Nothing }
766

767
768
769
770
771
-----------------------------------------------------------------------------
-- Stand-alone deriving

-- Glasgow extension: stand-alone deriving declarations
stand_alone_deriving :: { LDerivDecl RdrName }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
772
        : 'deriving' 'instance' inst_type { LL (DerivDecl $3) }
773

774
775
776
-----------------------------------------------------------------------------
-- Nested declarations

777
-- Declaration in class bodies
778
--
779
decl_cls  :: { Located (OrdList (LHsDecl RdrName)) }
780
decl_cls  : at_decl_cls                 { LL (unitOL $1) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
781
          | decl                        { $1 }
782

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
783
          -- A 'default' signature used with the generic-programming extension
784
785
786
787
          | 'default' infixexp '::' sigtypedoc
                    {% do { (TypeSig l ty) <- checkValSig $2 $4
                          ; return (LL $ unitOL (LL $ SigD (GenericSig l ty))) } }

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
788
789
790
791
792
decls_cls :: { Located (OrdList (LHsDecl RdrName)) }    -- Reversed
          : decls_cls ';' decl_cls      { LL (unLoc $1 `appOL` unLoc $3) }
          | decls_cls ';'               { LL (unLoc $1) }
          | decl_cls                    { $1 }
          | {- empty -}                 { noLoc nilOL }
793
794


795
decllist_cls
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
796
797
798
        :: { Located (OrdList (LHsDecl RdrName)) }      -- Reversed
        : '{'         decls_cls '}'     { LL (unLoc $2) }
        |     vocurly decls_cls close   { $2 }
799

800
-- Class body
801
--
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
802
803
804
805
806
where_cls :: { Located (OrdList (LHsDecl RdrName)) }    -- Reversed
                                -- No implicit parameters
                                -- May have type declarations
        : 'where' decllist_cls          { LL (unLoc $2) }
        | {- empty -}                   { noLoc nilOL }
807
808
809
810

-- Declarations in instance bodies
--
decl_inst  :: { Located (OrdList (LHsDecl RdrName)) }
811
decl_inst  : at_decl_inst               { LL (unitOL (L1 (InstD (FamInstD { lid_inst = unLoc $1 })))) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
812
           | decl                       { $1 }
813

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
814
815
816
817
818
decls_inst :: { Located (OrdList (LHsDecl RdrName)) }   -- Reversed
           : decls_inst ';' decl_inst   { LL (unLoc $1 `appOL` unLoc $3) }
           | decls_inst ';'             { LL (unLoc $1) }
           | decl_inst                  { $1 }
           | {- empty -}                { noLoc nilOL }
819
820

decllist_inst 
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
821
822
823
        :: { Located (OrdList (LHsDecl RdrName)) }      -- Reversed
        : '{'         decls_inst '}'    { LL (unLoc $2) }
        |     vocurly decls_inst close  { $2 }
824
825
826

-- Instance body
--
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
827
828
829
830
831
where_inst :: { Located (OrdList (LHsDecl RdrName)) }   -- Reversed
                                -- No implicit parameters
                                -- May have type declarations
        : 'where' decllist_inst         { LL (unLoc $2) }
        | {- empty -}                   { noLoc nilOL }
832

833
834
-- Declarations in binding groups other than classes and instances
--
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
835
836
decls   :: { Located (OrdList (LHsDecl RdrName)) }      
        : decls ';' decl                { let { this = unLoc $3;
Ian Lynagh's avatar
Ian Lynagh committed
837
                                    rest = unLoc $1;
Ian Lynagh's avatar
Ian Lynagh committed
838
                                    these = rest `appOL` this }
Ian Lynagh's avatar
Ian Lynagh committed
839
840
                              in rest `seq` this `seq` these `seq`
                                    LL these }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
841
842
843
        | decls ';'                     { LL (unLoc $1) }
        | decl                          { $1 }
        | {- empty -}                   { noLoc nilOL }
844

845
decllist :: { Located (OrdList (LHsDecl RdrName)) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
846
847
        : '{'            decls '}'      { LL (unLoc $2) }
        |     vocurly    decls close    { $2 }
848

849
850
-- Binding groups other than those of class and instance declarations
--
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
851
852
853
854
855
binds   ::  { Located (HsLocalBinds RdrName) }          -- May have implicit parameters
                                                -- No type declarations
        : decllist                      { L1 (HsValBinds (cvBindGroup (unLoc $1))) }
        | '{'            dbinds '}'     { LL (HsIPBinds (IPBinds (unLoc $2) emptyTcEvBinds)) }
        |     vocurly    dbinds close   { L (getLoc $2) (HsIPBinds (IPBinds (unLoc $2) emptyTcEvBinds)) }
856

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
857
858
859
860
wherebinds :: { Located (HsLocalBinds RdrName) }        -- May have implicit parameters
                                                -- No type declarations
        : 'where' binds                 { LL (unLoc $2) }
        | {- empty -}                   { noLoc emptyLocalBinds }
861
862
863
864
865


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

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
866
867
868
869
870
rules   :: { OrdList (LHsDecl RdrName) }
        :  rules ';' rule                       { $1 `snocOL` $3 }
        |  rules ';'                            { $1 }
        |  rule                                 { unitOL $1 }
        |  {- empty -}                          { nilOL }
871

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
872
873
874
875
876
rule    :: { LHsDecl RdrName }
        : STRING activation rule_forall infixexp '=' exp
             { LL $ RuleD (HsRule (getSTRING $1) 
                                  ($2 `orElse` AlwaysActive) 
                                  $3 $4 placeHolderNames $6 placeHolderNames) }
877

878
879
880
activation :: { Maybe Activation } 
        : {- empty -}                           { Nothing }
        | explicit_activation                   { Just $1 }
881
882

explicit_activation :: { Activation }  -- In brackets
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
883
884
        : '[' INTEGER ']'               { ActiveAfter  (fromInteger (getINTEGER $2)) }
        | '[' '~' INTEGER ']'           { ActiveBefore (fromInteger (getINTEGER $3)) }
885
	| '[' '~' ']'                   { NeverActive }
886
887

rule_forall :: { [RuleBndr RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
888
889
        : 'forall' rule_var_list '.'            { $2 }
        | {- empty -}                           { [] }
890
891

rule_var_list :: { [RuleBndr RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
892
893
        : rule_var                              { [$1] }
        | rule_var rule_var_list                { $1 : $2 }
894
895

rule_var :: { RuleBndr RdrName }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
896
        : varid                                 { RuleBndr $1 }
897
        | '(' varid '::' ctype ')'              { RuleBndrSig $2 (mkHsWithBndrs $4) }
898
899

-----------------------------------------------------------------------------
Ian Lynagh's avatar
Ian Lynagh committed
900
901
902
-- Warnings and deprecations (c.f. rules)

warnings :: { OrdList (LHsDecl RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
903
904
905
906
        : warnings ';' warning          { $1 `appOL` $3 }
        | warnings ';'                  { $1 }
        | warning                               { $1 }
        | {- empty -}                           { nilOL }
Ian Lynagh's avatar
Ian Lynagh committed
907
908
909

-- SUP: TEMPORARY HACK, not checking for `module Foo'
warning :: { OrdList (LHsDecl RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
910
911
912
        : namelist strings
                { toOL [ LL $ WarningD (Warning n (WarningTxt $ unLoc $2))
                       | n <- unLoc $1 ] }
913

914
deprecations :: { OrdList (LHsDecl RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
915
916
917
918
        : deprecations ';' deprecation          { $1 `appOL` $3 }
        | deprecations ';'                      { $1 }
        | deprecation                           { $1 }
        | {- empty -}                           { nilOL }
919
920

-- SUP: TEMPORARY HACK, not checking for `module Foo'
921
deprecation :: { OrdList (LHsDecl RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
922
923
924
        : namelist strings
                { toOL [ LL $ WarningD (Warning n (DeprecatedTxt $ unLoc $2))
                       | n <- unLoc $1 ] }
925

926
927
928
929
930
931
932
933
strings :: { Located [FastString] }
    : STRING { L1 [getSTRING $1] }
    | '[' stringlist ']' { LL $ fromOL (unLoc $2) }

stringlist :: { Located (OrdList FastString) }
    : stringlist ',' STRING { LL (unLoc $1 `snocOL` getSTRING $3) }
    | STRING                { LL (unitOL (getSTRING $1)) }

934
935
936
937
938
939
940
-----------------------------------------------------------------------------
-- Annotations
annotation :: { LHsDecl RdrName }
    : '{-# ANN' name_var aexp '#-}'      { LL (AnnD $ HsAnnotation (ValueAnnProvenance (unLoc $2)) $3) }
    | '{-# ANN' 'type' tycon aexp '#-}'  { LL (AnnD $ HsAnnotation (TypeAnnProvenance (unLoc $3)) $4) }
    | '{-# ANN' 'module' aexp '#-}'      { LL (AnnD $ HsAnnotation ModuleAnnProvenance $3) }

941
942
943
944
945

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

fdecl :: { LHsDecl RdrName }
Simon Marlow's avatar
Simon Marlow committed
946
fdecl : 'import' callconv safety fspec
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
947
948
949
950
                {% mkImport $2 $3 (unLoc $4) >>= return.LL }
      | 'import' callconv        fspec          
                {% do { d <- mkImport $2 PlaySafe (unLoc $3);
                        return (LL d) } }
951
      | 'export' callconv fspec
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
952
                {% mkExport $2 (unLoc $3) >>= return.LL }
953

954
callconv :: { CCallConv }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
955
956
          : 'stdcall'                   { StdCallConv }
          | 'ccall'                     { CCallConv   }
957
          | 'capi'                      { CApiConv    }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
958
          | 'prim'                      { PrimCallConv}
959
960

safety :: { Safety }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
961
962
963
        : 'unsafe'                      { PlayRisky }
        | 'safe'                        { PlaySafe }
        | 'interruptible'               { PlayInterruptible }
964
965

fspec :: { Located (Located FastString, Located RdrName, LHsType RdrName) }
966
967
       : STRING var '::' sigtypedoc     { LL (L (getLoc $1) (getSTRING $1), $2, $4) }
       |        var '::' sigtypedoc     { LL (noLoc nilFS, $1, $3) }
968
969
970
971
972
973
974
975
         -- if the entity string is missing, it defaults to the empty string;
         -- the meaning of an empty entity string depends on the calling
         -- convention

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

opt_sig :: { Maybe (LHsType RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
976
977
        : {- empty -}                   { Nothing }
        | '::' sigtype                  { Just $2 }
978
979

opt_asig :: { Maybe (LHsType RdrName) }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
980
981
        : {- empty -}                   { Nothing }
        | '::' atype                    { Just $2 }
982

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
983
sigtype :: { LHsType RdrName }          -- Always a HsForAllTy,
984
                                        -- to tell the renamer where to generalise
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
985
986
        : ctype                         { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
        -- Wrap an Implicit forall if there isn't one there already
987

988
sigtypedoc :: { LHsType RdrName }       -- Always a HsForAllTy
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
989
990
        : ctypedoc                      { L1 (mkImplicitHsForAllTy (noLoc []) $1) }
        -- Wrap an Implicit forall if there isn't one there already
991

992
sig_vars :: { Located [Located RdrName] }
chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
993
994
         : sig_vars ',' var             { LL ($3 : unLoc $1) }
         | var                          { L1 [$1] }
995

chak@cse.unsw.edu.au.'s avatar
chak@cse.unsw.edu.au. committed
996
997
998
sigtypes1 :: { [LHsType RdrName] }      -- Always HsForAllTys
        : sigtype                       { [ $1 ] }
        | sigtype ',' sigtypes1         { $1 : $3 }
999

1000
1001
1002
-----------------------------------------------------------------------------
-- Types

1003
infixtype :: { LHsType RdrName }
dreixel's avatar
dreixel committed
1004
1005
        : btype qtyconop type         { LL $ mkHsOpTy $1 $2 $3 }
        | btype tyvarop  type    { LL $ mkHsOpTy $1 $2 $3 }
1006

1007
strict_mark :: { Located HsBang }