Generate Typeable info at definition sites
[ghc.git] / compiler / deSugar / DsMeta.hs
1 {-# LANGUAGE CPP #-}
2
3 -----------------------------------------------------------------------------
4 --
5 -- (c) The University of Glasgow 2006
6 --
7 -- The purpose of this module is to transform an HsExpr into a CoreExpr which
8 -- when evaluated, returns a (Meta.Q Meta.Exp) computation analogous to the
9 -- input HsExpr. We do this in the DsM monad, which supplies access to
10 -- CoreExpr's of the "smart constructors" of the Meta.Exp datatype.
11 --
12 -- It also defines a bunch of knownKeyNames, in the same way as is done
13 -- in prelude/PrelNames. It's much more convenient to do it here, because
14 -- otherwise we have to recompile PrelNames whenever we add a Name, which is
15 -- a Royal Pain (triggers other recompilation).
16 -----------------------------------------------------------------------------
17
18 module DsMeta( dsBracket ) where
19
20 #include "HsVersions.h"
21
22 import {-# SOURCE #-} DsExpr ( dsExpr )
23
24 import MatchLit
25 import DsMonad
26
27 import qualified Language.Haskell.TH as TH
28
29 import HsSyn
30 import Class
31 import PrelNames
32 -- To avoid clashes with DsMeta.varName we must make a local alias for
33 -- OccName.varName we do this by removing varName from the import of
34 -- OccName above, making a qualified instance of OccName and using
35 -- OccNameAlias.varName where varName ws previously used in this file.
36 import qualified OccName( isDataOcc, isVarOcc, isTcOcc )
37
38 import Module
39 import Id
40 import Name hiding( isVarOcc, isTcOcc, varName, tcName )
41 import THNames
42 import NameEnv
43 import TcType
44 import TyCon
45 import TysWiredIn
46 import TysPrim ( liftedTypeKindTyConName, constraintKindTyConName )
47 import CoreSyn
48 import MkCore
49 import CoreUtils
50 import SrcLoc
51 import Unique
52 import BasicTypes
53 import Outputable
54 import Bag
55 import DynFlags
56 import FastString
57 import ForeignCall
58 import Util
59 import Maybes
60 import MonadUtils
61
62 import Data.ByteString ( unpack )
63 import Control.Monad
64 import Data.List
65
66 -----------------------------------------------------------------------------
67 dsBracket :: HsBracket Name -> [PendingTcSplice] -> DsM CoreExpr
68 -- Returns a CoreExpr of type TH.ExpQ
69 -- The quoted thing is parameterised over Name, even though it has
70 -- been type checked. We don't want all those type decorations!
71
72 dsBracket brack splices
73 = dsExtendMetaEnv new_bit (do_brack brack)
74 where
75 new_bit = mkNameEnv [(n, DsSplice (unLoc e)) | PendingTcSplice n e <- splices]
76
77 do_brack (VarBr _ n) = do { MkC e1 <- lookupOcc n ; return e1 }
78 do_brack (ExpBr e) = do { MkC e1 <- repLE e ; return e1 }
79 do_brack (PatBr p) = do { MkC p1 <- repTopP p ; return p1 }
80 do_brack (TypBr t) = do { MkC t1 <- repLTy t ; return t1 }
81 do_brack (DecBrG gp) = do { MkC ds1 <- repTopDs gp ; return ds1 }
82 do_brack (DecBrL _) = panic "dsBracket: unexpected DecBrL"
83 do_brack (TExpBr e) = do { MkC e1 <- repLE e ; return e1 }
84
85 {- -------------- Examples --------------------
86
87 [| \x -> x |]
88 ====>
89 gensym (unpackString "x"#) `bindQ` \ x1::String ->
90 lam (pvar x1) (var x1)
91
92
93 [| \x -> $(f [| x |]) |]
94 ====>
95 gensym (unpackString "x"#) `bindQ` \ x1::String ->
96 lam (pvar x1) (f (var x1))
97 -}
98
99
100 -------------------------------------------------------
101 -- Declarations
102 -------------------------------------------------------
103
104 repTopP :: LPat Name -> DsM (Core TH.PatQ)
105 repTopP pat = do { ss <- mkGenSyms (collectPatBinders pat)
106 ; pat' <- addBinds ss (repLP pat)
107 ; wrapGenSyms ss pat' }
108
109 repTopDs :: HsGroup Name -> DsM (Core (TH.Q [TH.Dec]))
110 repTopDs group@(HsGroup { hs_valds = valds
111 , hs_splcds = splcds
112 , hs_tyclds = tyclds
113 , hs_instds = instds
114 , hs_derivds = derivds
115 , hs_fixds = fixds
116 , hs_defds = defds
117 , hs_fords = fords
118 , hs_warnds = warnds
119 , hs_annds = annds
120 , hs_ruleds = ruleds
121 , hs_vects = vects
122 , hs_docs = docs })
123 = do { let { tv_bndrs = hsSigTvBinders valds
124 ; bndrs = tv_bndrs ++ hsGroupBinders group } ;
125 ss <- mkGenSyms bndrs ;
126
127 -- Bind all the names mainly to avoid repeated use of explicit strings.
128 -- Thus we get
129 -- do { t :: String <- genSym "T" ;
130 -- return (Data t [] ...more t's... }
131 -- The other important reason is that the output must mention
132 -- only "T", not "Foo:T" where Foo is the current module
133
134 decls <- addBinds ss (
135 do { val_ds <- rep_val_binds valds
136 ; _ <- mapM no_splice splcds
137 ; tycl_ds <- mapM repTyClD (tyClGroupConcat tyclds)
138 ; role_ds <- mapM repRoleD (concatMap group_roles tyclds)
139 ; inst_ds <- mapM repInstD instds
140 ; deriv_ds <- mapM repStandaloneDerivD derivds
141 ; fix_ds <- mapM repFixD fixds
142 ; _ <- mapM no_default_decl defds
143 ; for_ds <- mapM repForD fords
144 ; _ <- mapM no_warn (concatMap (wd_warnings . unLoc)
145 warnds)
146 ; ann_ds <- mapM repAnnD annds
147 ; rule_ds <- mapM repRuleD (concatMap (rds_rules . unLoc)
148 ruleds)
149 ; _ <- mapM no_vect vects
150 ; _ <- mapM no_doc docs
151
152 -- more needed
153 ; return (de_loc $ sort_by_loc $
154 val_ds ++ catMaybes tycl_ds ++ role_ds
155 ++ (concat fix_ds)
156 ++ inst_ds ++ rule_ds ++ for_ds
157 ++ ann_ds ++ deriv_ds) }) ;
158
159 decl_ty <- lookupType decQTyConName ;
160 let { core_list = coreList' decl_ty decls } ;
161
162 dec_ty <- lookupType decTyConName ;
163 q_decs <- repSequenceQ dec_ty core_list ;
164
165 wrapGenSyms ss q_decs
166 }
167 where
168 no_splice (L loc _)
169 = notHandledL loc "Splices within declaration brackets" empty
170 no_default_decl (L loc decl)
171 = notHandledL loc "Default declarations" (ppr decl)
172 no_warn (L loc (Warning thing _))
173 = notHandledL loc "WARNING and DEPRECATION pragmas" $
174 text "Pragma for declaration of" <+> ppr thing
175 no_vect (L loc decl)
176 = notHandledL loc "Vectorisation pragmas" (ppr decl)
177 no_doc (L loc _)
178 = notHandledL loc "Haddock documentation" empty
179
180 hsSigTvBinders :: HsValBinds Name -> [Name]
181 -- See Note [Scoped type variables in bindings]
182 hsSigTvBinders binds
183 = [hsLTyVarName tv | L _ (TypeSig _ (L _ (HsForAllTy Explicit _ qtvs _ _)) _) <- sigs
184 , tv <- hsQTvBndrs qtvs]
185 where
186 sigs = case binds of
187 ValBindsIn _ sigs -> sigs
188 ValBindsOut _ sigs -> sigs
189
190
191 {- Notes
192
193 Note [Scoped type variables in bindings]
194 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
195 Consider
196 f :: forall a. a -> a
197 f x = x::a
198 Here the 'forall a' brings 'a' into scope over the binding group.
199 To achieve this we
200
201 a) Gensym a binding for 'a' at the same time as we do one for 'f'
202 collecting the relevant binders with hsSigTvBinders
203
204 b) When processing the 'forall', don't gensym
205
206 The relevant places are signposted with references to this Note
207
208 Note [Binders and occurrences]
209 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
210 When we desugar [d| data T = MkT |]
211 we want to get
212 Data "T" [] [Con "MkT" []] []
213 and *not*
214 Data "Foo:T" [] [Con "Foo:MkT" []] []
215 That is, the new data decl should fit into whatever new module it is
216 asked to fit in. We do *not* clone, though; no need for this:
217 Data "T79" ....
218
219 But if we see this:
220 data T = MkT
221 foo = reifyDecl T
222
223 then we must desugar to
224 foo = Data "Foo:T" [] [Con "Foo:MkT" []] []
225
226 So in repTopDs we bring the binders into scope with mkGenSyms and addBinds.
227 And we use lookupOcc, rather than lookupBinder
228 in repTyClD and repC.
229
230 -}
231
232 -- represent associated family instances
233 --
234 repTyClD :: LTyClDecl Name -> DsM (Maybe (SrcSpan, Core TH.DecQ))
235
236 repTyClD (L loc (FamDecl { tcdFam = fam })) = liftM Just $ repFamilyDecl (L loc fam)
237
238 repTyClD (L loc (SynDecl { tcdLName = tc, tcdTyVars = tvs, tcdRhs = rhs }))
239 = do { tc1 <- lookupLOcc tc -- See note [Binders and occurrences]
240 ; dec <- addTyClTyVarBinds tvs $ \bndrs ->
241 repSynDecl tc1 bndrs rhs
242 ; return (Just (loc, dec)) }
243
244 repTyClD (L loc (DataDecl { tcdLName = tc, tcdTyVars = tvs, tcdDataDefn = defn }))
245 = do { tc1 <- lookupLOcc tc -- See note [Binders and occurrences]
246 ; tc_tvs <- mk_extra_tvs tc tvs defn
247 ; dec <- addTyClTyVarBinds tc_tvs $ \bndrs ->
248 repDataDefn tc1 bndrs Nothing (hsLTyVarNames tc_tvs) defn
249 ; return (Just (loc, dec)) }
250
251 repTyClD (L loc (ClassDecl { tcdCtxt = cxt, tcdLName = cls,
252 tcdTyVars = tvs, tcdFDs = fds,
253 tcdSigs = sigs, tcdMeths = meth_binds,
254 tcdATs = ats, tcdATDefs = atds }))
255 = do { cls1 <- lookupLOcc cls -- See note [Binders and occurrences]
256 ; dec <- addTyVarBinds tvs $ \bndrs ->
257 do { cxt1 <- repLContext cxt
258 ; sigs1 <- rep_sigs sigs
259 ; binds1 <- rep_binds meth_binds
260 ; fds1 <- repLFunDeps fds
261 ; ats1 <- repFamilyDecls ats
262 ; atds1 <- repAssocTyFamDefaults atds
263 ; decls1 <- coreList decQTyConName (ats1 ++ atds1 ++ sigs1 ++ binds1)
264 ; repClass cxt1 cls1 bndrs fds1 decls1
265 }
266 ; return $ Just (loc, dec)
267 }
268
269 -------------------------
270 repRoleD :: LRoleAnnotDecl Name -> DsM (SrcSpan, Core TH.DecQ)
271 repRoleD (L loc (RoleAnnotDecl tycon roles))
272 = do { tycon1 <- lookupLOcc tycon
273 ; roles1 <- mapM repRole roles
274 ; roles2 <- coreList roleTyConName roles1
275 ; dec <- repRoleAnnotD tycon1 roles2
276 ; return (loc, dec) }
277
278 -------------------------
279 repDataDefn :: Core TH.Name -> Core [TH.TyVarBndr]
280 -> Maybe (Core [TH.TypeQ])
281 -> [Name] -> HsDataDefn Name
282 -> DsM (Core TH.DecQ)
283 repDataDefn tc bndrs opt_tys tv_names
284 (HsDataDefn { dd_ND = new_or_data, dd_ctxt = cxt
285 , dd_cons = cons, dd_derivs = mb_derivs })
286 = do { cxt1 <- repLContext cxt
287 ; derivs1 <- repDerivs mb_derivs
288 ; case new_or_data of
289 NewType -> do { con1 <- repC tv_names (head cons)
290 ; case con1 of
291 [c] -> repNewtype cxt1 tc bndrs opt_tys c derivs1
292 _cs -> failWithDs (ptext
293 (sLit "Multiple constructors for newtype:")
294 <+> pprQuotedList
295 (con_names $ unLoc $ head cons))
296 }
297 DataType -> do { consL <- concatMapM (repC tv_names) cons
298 ; cons1 <- coreList conQTyConName consL
299 ; repData cxt1 tc bndrs opt_tys cons1 derivs1 } }
300
301 repSynDecl :: Core TH.Name -> Core [TH.TyVarBndr]
302 -> LHsType Name
303 -> DsM (Core TH.DecQ)
304 repSynDecl tc bndrs ty
305 = do { ty1 <- repLTy ty
306 ; repTySyn tc bndrs ty1 }
307
308 repFamilyDecl :: LFamilyDecl Name -> DsM (SrcSpan, Core TH.DecQ)
309 repFamilyDecl decl@(L loc (FamilyDecl { fdInfo = info,
310 fdLName = tc,
311 fdTyVars = tvs,
312 fdResultSig = L _ resultSig,
313 fdInjectivityAnn = injectivity }))
314 = do { tc1 <- lookupLOcc tc -- See note [Binders and occurrences]
315 ; let mkHsQTvs tvs = HsQTvs { hsq_kvs = [], hsq_tvs = tvs }
316 resTyVar = case resultSig of
317 TyVarSig bndr -> mkHsQTvs [bndr]
318 _ -> mkHsQTvs []
319 ; dec <- addTyClTyVarBinds tvs $ \bndrs ->
320 addTyClTyVarBinds resTyVar $ \_ ->
321 case info of
322 ClosedTypeFamily Nothing ->
323 notHandled "abstract closed type family" (ppr decl)
324 ClosedTypeFamily (Just eqns) ->
325 do { eqns1 <- mapM repTyFamEqn eqns
326 ; eqns2 <- coreList tySynEqnQTyConName eqns1
327 ; result <- repFamilyResultSig resultSig
328 ; inj <- repInjectivityAnn injectivity
329 ; repClosedFamilyD tc1 bndrs result inj eqns2 }
330 OpenTypeFamily ->
331 do { result <- repFamilyResultSig resultSig
332 ; inj <- repInjectivityAnn injectivity
333 ; repOpenFamilyD tc1 bndrs result inj }
334 DataFamily ->
335 do { kind <- repFamilyResultSigToMaybeKind resultSig
336 ; repDataFamilyD tc1 bndrs kind }
337 ; return (loc, dec)
338 }
339
340 -- | Represent result signature of a type family
341 repFamilyResultSig :: FamilyResultSig Name -> DsM (Core TH.FamilyResultSig)
342 repFamilyResultSig NoSig = repNoSig
343 repFamilyResultSig (KindSig ki) = do { ki' <- repLKind ki
344 ; repKindSig ki' }
345 repFamilyResultSig (TyVarSig bndr) = do { bndr' <- repTyVarBndr bndr
346 ; repTyVarSig bndr' }
347
348 -- | Represent result signature using a Maybe Kind. Used with data families,
349 -- where the result signature can be either missing or a kind but never a named
350 -- result variable.
351 repFamilyResultSigToMaybeKind :: FamilyResultSig Name
352 -> DsM (Core (Maybe TH.Kind))
353 repFamilyResultSigToMaybeKind NoSig =
354 do { coreNothing kindTyConName }
355 repFamilyResultSigToMaybeKind (KindSig ki) =
356 do { ki' <- repLKind ki
357 ; coreJust kindTyConName ki' }
358 repFamilyResultSigToMaybeKind _ = panic "repFamilyResultSigToMaybeKind"
359
360 -- | Represent injectivity annotation of a type family
361 repInjectivityAnn :: Maybe (LInjectivityAnn Name)
362 -> DsM (Core (Maybe TH.InjectivityAnn))
363 repInjectivityAnn Nothing =
364 do { coreNothing injAnnTyConName }
365 repInjectivityAnn (Just (L _ (InjectivityAnn lhs rhs))) =
366 do { lhs' <- lookupBinder (unLoc lhs)
367 ; rhs1 <- mapM (lookupBinder . unLoc) rhs
368 ; rhs2 <- coreList nameTyConName rhs1
369 ; injAnn <- rep2 injectivityAnnName [unC lhs', unC rhs2]
370 ; coreJust injAnnTyConName injAnn }
371
372 repFamilyDecls :: [LFamilyDecl Name] -> DsM [Core TH.DecQ]
373 repFamilyDecls fds = liftM de_loc (mapM repFamilyDecl fds)
374
375 repAssocTyFamDefaults :: [LTyFamDefltEqn Name] -> DsM [Core TH.DecQ]
376 repAssocTyFamDefaults = mapM rep_deflt
377 where
378 -- very like repTyFamEqn, but different in the details
379 rep_deflt :: LTyFamDefltEqn Name -> DsM (Core TH.DecQ)
380 rep_deflt (L _ (TyFamEqn { tfe_tycon = tc
381 , tfe_pats = bndrs
382 , tfe_rhs = rhs }))
383 = addTyClTyVarBinds bndrs $ \ _ ->
384 do { tc1 <- lookupLOcc tc
385 ; tys1 <- repLTys (hsLTyVarBndrsToTypes bndrs)
386 ; tys2 <- coreList typeQTyConName tys1
387 ; rhs1 <- repLTy rhs
388 ; eqn1 <- repTySynEqn tys2 rhs1
389 ; repTySynInst tc1 eqn1 }
390
391 -------------------------
392 mk_extra_tvs :: Located Name -> LHsTyVarBndrs Name
393 -> HsDataDefn Name -> DsM (LHsTyVarBndrs Name)
394 -- If there is a kind signature it must be of form
395 -- k1 -> .. -> kn -> *
396 -- Return type variables [tv1:k1, tv2:k2, .., tvn:kn]
397 mk_extra_tvs tc tvs defn
398 | HsDataDefn { dd_kindSig = Just hs_kind } <- defn
399 = do { extra_tvs <- go hs_kind
400 ; return (tvs { hsq_tvs = hsq_tvs tvs ++ extra_tvs }) }
401 | otherwise
402 = return tvs
403 where
404 go :: LHsKind Name -> DsM [LHsTyVarBndr Name]
405 go (L loc (HsFunTy kind rest))
406 = do { uniq <- newUnique
407 ; let { occ = mkTyVarOccFS (fsLit "t")
408 ; nm = mkInternalName uniq occ loc
409 ; hs_tv = L loc (KindedTyVar (noLoc nm) kind) }
410 ; hs_tvs <- go rest
411 ; return (hs_tv : hs_tvs) }
412
413 go (L _ (HsTyVar n))
414 | n == liftedTypeKindTyConName
415 = return []
416
417 go _ = failWithDs (ptext (sLit "Malformed kind signature for") <+> ppr tc)
418
419 -------------------------
420 -- represent fundeps
421 --
422 repLFunDeps :: [Located (FunDep (Located Name))] -> DsM (Core [TH.FunDep])
423 repLFunDeps fds = repList funDepTyConName repLFunDep fds
424
425 repLFunDep :: Located (FunDep (Located Name)) -> DsM (Core TH.FunDep)
426 repLFunDep (L _ (xs, ys))
427 = do xs' <- repList nameTyConName (lookupBinder . unLoc) xs
428 ys' <- repList nameTyConName (lookupBinder . unLoc) ys
429 repFunDep xs' ys'
430
431 -- Represent instance declarations
432 --
433 repInstD :: LInstDecl Name -> DsM (SrcSpan, Core TH.DecQ)
434 repInstD (L loc (TyFamInstD { tfid_inst = fi_decl }))
435 = do { dec <- repTyFamInstD fi_decl
436 ; return (loc, dec) }
437 repInstD (L loc (DataFamInstD { dfid_inst = fi_decl }))
438 = do { dec <- repDataFamInstD fi_decl
439 ; return (loc, dec) }
440 repInstD (L loc (ClsInstD { cid_inst = cls_decl }))
441 = do { dec <- repClsInstD cls_decl
442 ; return (loc, dec) }
443
444 repClsInstD :: ClsInstDecl Name -> DsM (Core TH.DecQ)
445 repClsInstD (ClsInstDecl { cid_poly_ty = ty, cid_binds = binds
446 , cid_sigs = prags, cid_tyfam_insts = ats
447 , cid_datafam_insts = adts })
448 = addTyVarBinds tvs $ \_ ->
449 -- We must bring the type variables into scope, so their
450 -- occurrences don't fail, even though the binders don't
451 -- appear in the resulting data structure
452 --
453 -- But we do NOT bring the binders of 'binds' into scope
454 -- because they are properly regarded as occurrences
455 -- For example, the method names should be bound to
456 -- the selector Ids, not to fresh names (Trac #5410)
457 --
458 do { cxt1 <- repContext cxt
459 ; cls_tcon <- repTy (HsTyVar (unLoc cls))
460 ; cls_tys <- repLTys tys
461 ; inst_ty1 <- repTapps cls_tcon cls_tys
462 ; binds1 <- rep_binds binds
463 ; prags1 <- rep_sigs prags
464 ; ats1 <- mapM (repTyFamInstD . unLoc) ats
465 ; adts1 <- mapM (repDataFamInstD . unLoc) adts
466 ; decls <- coreList decQTyConName (ats1 ++ adts1 ++ binds1 ++ prags1)
467 ; repInst cxt1 inst_ty1 decls }
468 where
469 Just (tvs, cxt, cls, tys) = splitLHsInstDeclTy_maybe ty
470
471 repStandaloneDerivD :: LDerivDecl Name -> DsM (SrcSpan, Core TH.DecQ)
472 repStandaloneDerivD (L loc (DerivDecl { deriv_type = ty }))
473 = do { dec <- addTyVarBinds tvs $ \_ ->
474 do { cxt' <- repContext cxt
475 ; cls_tcon <- repTy (HsTyVar (unLoc cls))
476 ; cls_tys <- repLTys tys
477 ; inst_ty <- repTapps cls_tcon cls_tys
478 ; repDeriv cxt' inst_ty }
479 ; return (loc, dec) }
480 where
481 Just (tvs, cxt, cls, tys) = splitLHsInstDeclTy_maybe ty
482
483 repTyFamInstD :: TyFamInstDecl Name -> DsM (Core TH.DecQ)
484 repTyFamInstD decl@(TyFamInstDecl { tfid_eqn = eqn })
485 = do { let tc_name = tyFamInstDeclLName decl
486 ; tc <- lookupLOcc tc_name -- See note [Binders and occurrences]
487 ; eqn1 <- repTyFamEqn eqn
488 ; repTySynInst tc eqn1 }
489
490 repTyFamEqn :: LTyFamInstEqn Name -> DsM (Core TH.TySynEqnQ)
491 repTyFamEqn (L loc (TyFamEqn { tfe_pats = HsWB { hswb_cts = tys
492 , hswb_kvs = kv_names
493 , hswb_tvs = tv_names }
494 , tfe_rhs = rhs }))
495 = do { let hs_tvs = HsQTvs { hsq_kvs = kv_names
496 , hsq_tvs = userHsTyVarBndrs loc tv_names } -- Yuk
497 ; addTyClTyVarBinds hs_tvs $ \ _ ->
498 do { tys1 <- repLTys tys
499 ; tys2 <- coreList typeQTyConName tys1
500 ; rhs1 <- repLTy rhs
501 ; repTySynEqn tys2 rhs1 } }
502
503 repDataFamInstD :: DataFamInstDecl Name -> DsM (Core TH.DecQ)
504 repDataFamInstD (DataFamInstDecl { dfid_tycon = tc_name
505 , dfid_pats = HsWB { hswb_cts = tys, hswb_kvs = kv_names, hswb_tvs = tv_names }
506 , dfid_defn = defn })
507 = do { tc <- lookupLOcc tc_name -- See note [Binders and occurrences]
508 ; let loc = getLoc tc_name
509 hs_tvs = HsQTvs { hsq_kvs = kv_names, hsq_tvs = userHsTyVarBndrs loc tv_names } -- Yuk
510 ; addTyClTyVarBinds hs_tvs $ \ bndrs ->
511 do { tys1 <- repList typeQTyConName repLTy tys
512 ; repDataDefn tc bndrs (Just tys1) tv_names defn } }
513
514 repForD :: Located (ForeignDecl Name) -> DsM (SrcSpan, Core TH.DecQ)
515 repForD (L loc (ForeignImport name typ _ (CImport (L _ cc) (L _ s) mch cis _)))
516 = do MkC name' <- lookupLOcc name
517 MkC typ' <- repLTy typ
518 MkC cc' <- repCCallConv cc
519 MkC s' <- repSafety s
520 cis' <- conv_cimportspec cis
521 MkC str <- coreStringLit (static ++ chStr ++ cis')
522 dec <- rep2 forImpDName [cc', s', str, name', typ']
523 return (loc, dec)
524 where
525 conv_cimportspec (CLabel cls) = notHandled "Foreign label" (doubleQuotes (ppr cls))
526 conv_cimportspec (CFunction DynamicTarget) = return "dynamic"
527 conv_cimportspec (CFunction (StaticTarget _ fs _ True))
528 = return (unpackFS fs)
529 conv_cimportspec (CFunction (StaticTarget _ _ _ False))
530 = panic "conv_cimportspec: values not supported yet"
531 conv_cimportspec CWrapper = return "wrapper"
532 -- these calling conventions do not support headers and the static keyword
533 raw_cconv = cc == PrimCallConv || cc == JavaScriptCallConv
534 static = case cis of
535 CFunction (StaticTarget _ _ _ _) | not raw_cconv -> "static "
536 _ -> ""
537 chStr = case mch of
538 Just (Header _ h) | not raw_cconv -> unpackFS h ++ " "
539 _ -> ""
540 repForD decl = notHandled "Foreign declaration" (ppr decl)
541
542 repCCallConv :: CCallConv -> DsM (Core TH.Callconv)
543 repCCallConv CCallConv = rep2 cCallName []
544 repCCallConv StdCallConv = rep2 stdCallName []
545 repCCallConv CApiConv = rep2 cApiCallName []
546 repCCallConv PrimCallConv = rep2 primCallName []
547 repCCallConv JavaScriptCallConv = rep2 javaScriptCallName []
548
549 repSafety :: Safety -> DsM (Core TH.Safety)
550 repSafety PlayRisky = rep2 unsafeName []
551 repSafety PlayInterruptible = rep2 interruptibleName []
552 repSafety PlaySafe = rep2 safeName []
553
554 repFixD :: LFixitySig Name -> DsM [(SrcSpan, Core TH.DecQ)]
555 repFixD (L loc (FixitySig names (Fixity prec dir)))
556 = do { MkC prec' <- coreIntLit prec
557 ; let rep_fn = case dir of
558 InfixL -> infixLDName
559 InfixR -> infixRDName
560 InfixN -> infixNDName
561 ; let do_one name
562 = do { MkC name' <- lookupLOcc name
563 ; dec <- rep2 rep_fn [prec', name']
564 ; return (loc,dec) }
565 ; mapM do_one names }
566
567 repRuleD :: LRuleDecl Name -> DsM (SrcSpan, Core TH.DecQ)
568 repRuleD (L loc (HsRule n act bndrs lhs _ rhs _))
569 = do { let bndr_names = concatMap ruleBndrNames bndrs
570 ; ss <- mkGenSyms bndr_names
571 ; rule1 <- addBinds ss $
572 do { bndrs' <- repList ruleBndrQTyConName repRuleBndr bndrs
573 ; n' <- coreStringLit $ unpackFS $ snd $ unLoc n
574 ; act' <- repPhases act
575 ; lhs' <- repLE lhs
576 ; rhs' <- repLE rhs
577 ; repPragRule n' bndrs' lhs' rhs' act' }
578 ; rule2 <- wrapGenSyms ss rule1
579 ; return (loc, rule2) }
580
581 ruleBndrNames :: LRuleBndr Name -> [Name]
582 ruleBndrNames (L _ (RuleBndr n)) = [unLoc n]
583 ruleBndrNames (L _ (RuleBndrSig n (HsWB { hswb_kvs = kvs, hswb_tvs = tvs })))
584 = unLoc n : kvs ++ tvs
585
586 repRuleBndr :: LRuleBndr Name -> DsM (Core TH.RuleBndrQ)
587 repRuleBndr (L _ (RuleBndr n))
588 = do { MkC n' <- lookupLBinder n
589 ; rep2 ruleVarName [n'] }
590 repRuleBndr (L _ (RuleBndrSig n (HsWB { hswb_cts = ty })))
591 = do { MkC n' <- lookupLBinder n
592 ; MkC ty' <- repLTy ty
593 ; rep2 typedRuleVarName [n', ty'] }
594
595 repAnnD :: LAnnDecl Name -> DsM (SrcSpan, Core TH.DecQ)
596 repAnnD (L loc (HsAnnotation _ ann_prov (L _ exp)))
597 = do { target <- repAnnProv ann_prov
598 ; exp' <- repE exp
599 ; dec <- repPragAnn target exp'
600 ; return (loc, dec) }
601
602 repAnnProv :: AnnProvenance Name -> DsM (Core TH.AnnTarget)
603 repAnnProv (ValueAnnProvenance (L _ n))
604 = do { MkC n' <- globalVar n -- ANNs are allowed only at top-level
605 ; rep2 valueAnnotationName [ n' ] }
606 repAnnProv (TypeAnnProvenance (L _ n))
607 = do { MkC n' <- globalVar n
608 ; rep2 typeAnnotationName [ n' ] }
609 repAnnProv ModuleAnnProvenance
610 = rep2 moduleAnnotationName []
611
612 -------------------------------------------------------
613 -- Constructors
614 -------------------------------------------------------
615
616 repC :: [Name] -> LConDecl Name -> DsM [Core TH.ConQ]
617 repC _ (L _ (ConDecl { con_names = con, con_qvars = con_tvs, con_cxt = L _ []
618 , con_details = details, con_res = ResTyH98 }))
619 | null (hsQTvBndrs con_tvs)
620 = do { con1 <- mapM lookupLOcc con -- See Note [Binders and occurrences]
621 ; mapM (\c -> repConstr c details) con1 }
622
623 repC tvs (L _ (ConDecl { con_names = cons
624 , con_qvars = con_tvs, con_cxt = L _ ctxt
625 , con_details = details
626 , con_res = res_ty }))
627 = do { (eq_ctxt, con_tv_subst) <- mkGadtCtxt tvs res_ty
628 ; let ex_tvs = HsQTvs { hsq_kvs = filterOut (in_subst con_tv_subst) (hsq_kvs con_tvs)
629 , hsq_tvs = filterOut (in_subst con_tv_subst . hsLTyVarName) (hsq_tvs con_tvs) }
630
631 ; binds <- mapM dupBinder con_tv_subst
632 ; b <- dsExtendMetaEnv (mkNameEnv binds) $ -- Binds some of the con_tvs
633 addTyVarBinds ex_tvs $ \ ex_bndrs -> -- Binds the remaining con_tvs
634 do { cons1 <- mapM lookupLOcc cons -- See Note [Binders and occurrences]
635 ; c' <- mapM (\c -> repConstr c details) cons1
636 ; ctxt' <- repContext (eq_ctxt ++ ctxt)
637 ; rep2 forallCName ([unC ex_bndrs, unC ctxt'] ++ (map unC c')) }
638 ; return [b]
639 }
640
641 in_subst :: [(Name,Name)] -> Name -> Bool
642 in_subst [] _ = False
643 in_subst ((n',_):ns) n = n==n' || in_subst ns n
644
645 mkGadtCtxt :: [Name] -- Tyvars of the data type
646 -> ResType (LHsType Name)
647 -> DsM (HsContext Name, [(Name,Name)])
648 -- Given a data type in GADT syntax, figure out the equality
649 -- context, so that we can represent it with an explicit
650 -- equality context, because that is the only way to express
651 -- the GADT in TH syntax
652 --
653 -- Example:
654 -- data T a b c where { MkT :: forall d e. d -> e -> T d [e] e
655 -- mkGadtCtxt [a,b,c] [d,e] (T d [e] e)
656 -- returns
657 -- (b~[e], c~e), [d->a]
658 --
659 -- This function is fiddly, but not really hard
660 mkGadtCtxt _ ResTyH98
661 = return ([], [])
662 mkGadtCtxt data_tvs (ResTyGADT _ res_ty)
663 | Just (_, tys) <- hsTyGetAppHead_maybe res_ty
664 , data_tvs `equalLength` tys
665 = return (go [] [] (data_tvs `zip` tys))
666
667 | otherwise
668 = failWithDs (ptext (sLit "Malformed constructor result type:") <+> ppr res_ty)
669 where
670 go cxt subst [] = (cxt, subst)
671 go cxt subst ((data_tv, ty) : rest)
672 | Just con_tv <- is_hs_tyvar ty
673 , isTyVarName con_tv
674 , not (in_subst subst con_tv)
675 = go cxt ((con_tv, data_tv) : subst) rest
676 | otherwise
677 = go (eq_pred : cxt) subst rest
678 where
679 loc = getLoc ty
680 eq_pred = L loc (HsEqTy (L loc (HsTyVar data_tv)) ty)
681
682 is_hs_tyvar (L _ (HsTyVar n)) = Just n -- Type variables *and* tycons
683 is_hs_tyvar (L _ (HsParTy ty)) = is_hs_tyvar ty
684 is_hs_tyvar _ = Nothing
685
686
687 repBangTy :: LBangType Name -> DsM (Core (TH.StrictTypeQ))
688 repBangTy ty = do
689 MkC s <- rep2 str []
690 MkC t <- repLTy ty'
691 rep2 strictTypeName [s, t]
692 where
693 (str, ty') = case ty of
694 L _ (HsBangTy (HsSrcBang _ SrcUnpack SrcStrict) ty)
695 -> (unpackedName, ty)
696 L _ (HsBangTy (HsSrcBang _ _ SrcStrict) ty)
697 -> (isStrictName, ty)
698 _ -> (notStrictName, ty)
699
700 -------------------------------------------------------
701 -- Deriving clause
702 -------------------------------------------------------
703
704 repDerivs :: Maybe (Located [LHsType Name]) -> DsM (Core [TH.Name])
705 repDerivs Nothing = coreList nameTyConName []
706 repDerivs (Just (L _ ctxt))
707 = repList nameTyConName rep_deriv ctxt
708 where
709 rep_deriv :: LHsType Name -> DsM (Core TH.Name)
710 -- Deriving clauses must have the simple H98 form
711 rep_deriv ty
712 | Just (cls, []) <- splitHsClassTy_maybe (unLoc ty)
713 = lookupOcc cls
714 | otherwise
715 = notHandled "Non-H98 deriving clause" (ppr ty)
716
717
718 -------------------------------------------------------
719 -- Signatures in a class decl, or a group of bindings
720 -------------------------------------------------------
721
722 rep_sigs :: [LSig Name] -> DsM [Core TH.DecQ]
723 rep_sigs sigs = do locs_cores <- rep_sigs' sigs
724 return $ de_loc $ sort_by_loc locs_cores
725
726 rep_sigs' :: [LSig Name] -> DsM [(SrcSpan, Core TH.DecQ)]
727 -- We silently ignore ones we don't recognise
728 rep_sigs' sigs = do { sigs1 <- mapM rep_sig sigs ;
729 return (concat sigs1) }
730
731 rep_sig :: LSig Name -> DsM [(SrcSpan, Core TH.DecQ)]
732 rep_sig (L loc (TypeSig nms ty _)) = mapM (rep_ty_sig sigDName loc ty) nms
733 rep_sig (L _ (PatSynSig {})) = notHandled "Pattern type signatures" empty
734 rep_sig (L loc (GenericSig nms ty)) = mapM (rep_ty_sig defaultSigDName loc ty) nms
735 rep_sig d@(L _ (IdSig {})) = pprPanic "rep_sig IdSig" (ppr d)
736 rep_sig (L _ (FixSig {})) = return [] -- fixity sigs at top level
737 rep_sig (L loc (InlineSig nm ispec)) = rep_inline nm ispec loc
738 rep_sig (L loc (SpecSig nm tys ispec))
739 = concatMapM (\t -> rep_specialise nm t ispec loc) tys
740 rep_sig (L loc (SpecInstSig _ ty)) = rep_specialiseInst ty loc
741 rep_sig (L _ (MinimalSig {})) = notHandled "MINIMAL pragmas" empty
742
743 rep_ty_sig :: Name -> SrcSpan -> LHsType Name -> Located Name
744 -> DsM (SrcSpan, Core TH.DecQ)
745 rep_ty_sig mk_sig loc (L _ ty) nm
746 = do { nm1 <- lookupLOcc nm
747 ; ty1 <- rep_ty ty
748 ; sig <- repProto mk_sig nm1 ty1
749 ; return (loc, sig) }
750 where
751 -- We must special-case the top-level explicit for-all of a TypeSig
752 -- See Note [Scoped type variables in bindings]
753 rep_ty (HsForAllTy Explicit _ tvs ctxt ty)
754 = do { let rep_in_scope_tv tv = do { name <- lookupBinder (hsLTyVarName tv)
755 ; repTyVarBndrWithKind tv name }
756 ; bndrs1 <- repList tyVarBndrTyConName rep_in_scope_tv (hsQTvBndrs tvs)
757 ; ctxt1 <- repLContext ctxt
758 ; ty1 <- repLTy ty
759 ; repTForall bndrs1 ctxt1 ty1 }
760
761 rep_ty ty = repTy ty
762
763 rep_inline :: Located Name
764 -> InlinePragma -- Never defaultInlinePragma
765 -> SrcSpan
766 -> DsM [(SrcSpan, Core TH.DecQ)]
767 rep_inline nm ispec loc
768 = do { nm1 <- lookupLOcc nm
769 ; inline <- repInline $ inl_inline ispec
770 ; rm <- repRuleMatch $ inl_rule ispec
771 ; phases <- repPhases $ inl_act ispec
772 ; pragma <- repPragInl nm1 inline rm phases
773 ; return [(loc, pragma)]
774 }
775
776 rep_specialise :: Located Name -> LHsType Name -> InlinePragma -> SrcSpan
777 -> DsM [(SrcSpan, Core TH.DecQ)]
778 rep_specialise nm ty ispec loc
779 = do { nm1 <- lookupLOcc nm
780 ; ty1 <- repLTy ty
781 ; phases <- repPhases $ inl_act ispec
782 ; let inline = inl_inline ispec
783 ; pragma <- if isEmptyInlineSpec inline
784 then -- SPECIALISE
785 repPragSpec nm1 ty1 phases
786 else -- SPECIALISE INLINE
787 do { inline1 <- repInline inline
788 ; repPragSpecInl nm1 ty1 inline1 phases }
789 ; return [(loc, pragma)]
790 }
791
792 rep_specialiseInst :: LHsType Name -> SrcSpan -> DsM [(SrcSpan, Core TH.DecQ)]
793 rep_specialiseInst ty loc
794 = do { ty1 <- repLTy ty
795 ; pragma <- repPragSpecInst ty1
796 ; return [(loc, pragma)] }
797
798 repInline :: InlineSpec -> DsM (Core TH.Inline)
799 repInline NoInline = dataCon noInlineDataConName
800 repInline Inline = dataCon inlineDataConName
801 repInline Inlinable = dataCon inlinableDataConName
802 repInline spec = notHandled "repInline" (ppr spec)
803
804 repRuleMatch :: RuleMatchInfo -> DsM (Core TH.RuleMatch)
805 repRuleMatch ConLike = dataCon conLikeDataConName
806 repRuleMatch FunLike = dataCon funLikeDataConName
807
808 repPhases :: Activation -> DsM (Core TH.Phases)
809 repPhases (ActiveBefore i) = do { MkC arg <- coreIntLit i
810 ; dataCon' beforePhaseDataConName [arg] }
811 repPhases (ActiveAfter i) = do { MkC arg <- coreIntLit i
812 ; dataCon' fromPhaseDataConName [arg] }
813 repPhases _ = dataCon allPhasesDataConName
814
815 -------------------------------------------------------
816 -- Types
817 -------------------------------------------------------
818
819 addTyVarBinds :: LHsTyVarBndrs Name -- the binders to be added
820 -> (Core [TH.TyVarBndr] -> DsM (Core (TH.Q a))) -- action in the ext env
821 -> DsM (Core (TH.Q a))
822 -- gensym a list of type variables and enter them into the meta environment;
823 -- the computations passed as the second argument is executed in that extended
824 -- meta environment and gets the *new* names on Core-level as an argument
825
826 addTyVarBinds (HsQTvs { hsq_kvs = kvs, hsq_tvs = tvs }) m
827 = do { fresh_kv_names <- mkGenSyms kvs
828 ; fresh_tv_names <- mkGenSyms (map hsLTyVarName tvs)
829 ; let fresh_names = fresh_kv_names ++ fresh_tv_names
830 ; term <- addBinds fresh_names $
831 do { kbs <- repList tyVarBndrTyConName mk_tv_bndr (tvs `zip` fresh_tv_names)
832 ; m kbs }
833 ; wrapGenSyms fresh_names term }
834 where
835 mk_tv_bndr (tv, (_,v)) = repTyVarBndrWithKind tv (coreVar v)
836
837 addTyClTyVarBinds :: LHsTyVarBndrs Name
838 -> (Core [TH.TyVarBndr] -> DsM (Core (TH.Q a)))
839 -> DsM (Core (TH.Q a))
840
841 -- Used for data/newtype declarations, and family instances,
842 -- so that the nested type variables work right
843 -- instance C (T a) where
844 -- type W (T a) = blah
845 -- The 'a' in the type instance is the one bound by the instance decl
846 addTyClTyVarBinds tvs m
847 = do { let tv_names = hsLKiTyVarNames tvs
848 ; env <- dsGetMetaEnv
849 ; freshNames <- mkGenSyms (filterOut (`elemNameEnv` env) tv_names)
850 -- Make fresh names for the ones that are not already in scope
851 -- This makes things work for family declarations
852
853 ; term <- addBinds freshNames $
854 do { kbs <- repList tyVarBndrTyConName mk_tv_bndr (hsQTvBndrs tvs)
855 ; m kbs }
856
857 ; wrapGenSyms freshNames term }
858 where
859 mk_tv_bndr tv = do { v <- lookupBinder (hsLTyVarName tv)
860 ; repTyVarBndrWithKind tv v }
861
862 -- Produce kinded binder constructors from the Haskell tyvar binders
863 --
864 repTyVarBndrWithKind :: LHsTyVarBndr Name
865 -> Core TH.Name -> DsM (Core TH.TyVarBndr)
866 repTyVarBndrWithKind (L _ (UserTyVar _)) nm
867 = repPlainTV nm
868 repTyVarBndrWithKind (L _ (KindedTyVar _ ki)) nm
869 = repLKind ki >>= repKindedTV nm
870
871 -- | Represent a type variable binder
872 repTyVarBndr :: LHsTyVarBndr Name -> DsM (Core TH.TyVarBndr)
873 repTyVarBndr (L _ (UserTyVar nm)) = do { nm' <- lookupBinder nm
874 ; repPlainTV nm' }
875 repTyVarBndr (L _ (KindedTyVar (L _ nm) ki)) = do { nm' <- lookupBinder nm
876 ; ki' <- repLKind ki
877 ; repKindedTV nm' ki' }
878
879 -- represent a type context
880 --
881 repLContext :: LHsContext Name -> DsM (Core TH.CxtQ)
882 repLContext (L _ ctxt) = repContext ctxt
883
884 repContext :: HsContext Name -> DsM (Core TH.CxtQ)
885 repContext ctxt = do preds <- repList typeQTyConName repLTy ctxt
886 repCtxt preds
887
888 -- yield the representation of a list of types
889 --
890 repLTys :: [LHsType Name] -> DsM [Core TH.TypeQ]
891 repLTys tys = mapM repLTy tys
892
893 -- represent a type
894 --
895 repLTy :: LHsType Name -> DsM (Core TH.TypeQ)
896 repLTy (L _ ty) = repTy ty
897
898 repTy :: HsType Name -> DsM (Core TH.TypeQ)
899 repTy (HsForAllTy _ extra tvs ctxt ty) =
900 addTyVarBinds tvs $ \bndrs -> do
901 ctxt1 <- repLContext ctxt'
902 ty1 <- repLTy ty
903 repTForall bndrs ctxt1 ty1
904 where
905 -- If extra is not Nothing, an extra-constraints wild card was removed
906 -- (just) before renaming. It must be put back now, otherwise the
907 -- represented type won't include this extra-constraints wild card.
908 ctxt'
909 | Just loc <- extra
910 = let uniq = panic "addExtraCtsWC"
911 -- This unique will be discarded by repLContext, but is required
912 -- to make a Name
913 name = mkInternalName uniq (mkTyVarOcc "_") loc
914 in (++ [L loc (HsWildCardTy (AnonWildCard name))]) `fmap` ctxt
915 | otherwise
916 = ctxt
917
918
919
920 repTy (HsTyVar n)
921 | isTvOcc occ = do tv1 <- lookupOcc n
922 repTvar tv1
923 | isDataOcc occ = do tc1 <- lookupOcc n
924 repPromotedTyCon tc1
925 | otherwise = do tc1 <- lookupOcc n
926 repNamedTyCon tc1
927 where
928 occ = nameOccName n
929
930 repTy (HsAppTy f a) = do
931 f1 <- repLTy f
932 a1 <- repLTy a
933 repTapp f1 a1
934 repTy (HsFunTy f a) = do
935 f1 <- repLTy f
936 a1 <- repLTy a
937 tcon <- repArrowTyCon
938 repTapps tcon [f1, a1]
939 repTy (HsListTy t) = do
940 t1 <- repLTy t
941 tcon <- repListTyCon
942 repTapp tcon t1
943 repTy (HsPArrTy t) = do
944 t1 <- repLTy t
945 tcon <- repTy (HsTyVar (tyConName parrTyCon))
946 repTapp tcon t1
947 repTy (HsTupleTy HsUnboxedTuple tys) = do
948 tys1 <- repLTys tys
949 tcon <- repUnboxedTupleTyCon (length tys)
950 repTapps tcon tys1
951 repTy (HsTupleTy _ tys) = do tys1 <- repLTys tys
952 tcon <- repTupleTyCon (length tys)
953 repTapps tcon tys1
954 repTy (HsOpTy ty1 (_, n) ty2) = repLTy ((nlHsTyVar (unLoc n) `nlHsAppTy` ty1)
955 `nlHsAppTy` ty2)
956 repTy (HsParTy t) = repLTy t
957 repTy (HsEqTy t1 t2) = do
958 t1' <- repLTy t1
959 t2' <- repLTy t2
960 eq <- repTequality
961 repTapps eq [t1', t2']
962 repTy (HsKindSig t k) = do
963 t1 <- repLTy t
964 k1 <- repLKind k
965 repTSig t1 k1
966 repTy (HsSpliceTy splice _) = repSplice splice
967 repTy (HsExplicitListTy _ tys) = do
968 tys1 <- repLTys tys
969 repTPromotedList tys1
970 repTy (HsExplicitTupleTy _ tys) = do
971 tys1 <- repLTys tys
972 tcon <- repPromotedTupleTyCon (length tys)
973 repTapps tcon tys1
974 repTy (HsTyLit lit) = do
975 lit' <- repTyLit lit
976 repTLit lit'
977 repTy (HsWildCardTy (AnonWildCard _)) = repTWildCard
978 repTy (HsWildCardTy (NamedWildCard n)) = do
979 nwc <- lookupOcc n
980 repTNamedWildCard nwc
981
982 repTy ty = notHandled "Exotic form of type" (ppr ty)
983
984 repTyLit :: HsTyLit -> DsM (Core TH.TyLitQ)
985 repTyLit (HsNumTy _ i) = do iExpr <- mkIntegerExpr i
986 rep2 numTyLitName [iExpr]
987 repTyLit (HsStrTy _ s) = do { s' <- mkStringExprFS s
988 ; rep2 strTyLitName [s']
989 }
990
991 -- represent a kind
992 --
993 repLKind :: LHsKind Name -> DsM (Core TH.Kind)
994 repLKind ki
995 = do { let (kis, ki') = splitHsFunType ki
996 ; kis_rep <- mapM repLKind kis
997 ; ki'_rep <- repNonArrowLKind ki'
998 ; kcon <- repKArrow
999 ; let f k1 k2 = repKApp kcon k1 >>= flip repKApp k2
1000 ; foldrM f ki'_rep kis_rep
1001 }
1002
1003 repNonArrowLKind :: LHsKind Name -> DsM (Core TH.Kind)
1004 repNonArrowLKind (L _ ki) = repNonArrowKind ki
1005
1006 repNonArrowKind :: HsKind Name -> DsM (Core TH.Kind)
1007 repNonArrowKind (HsTyVar name)
1008 | name == liftedTypeKindTyConName = repKStar
1009 | name == constraintKindTyConName = repKConstraint
1010 | isTvOcc (nameOccName name) = lookupOcc name >>= repKVar
1011 | otherwise = lookupOcc name >>= repKCon
1012 repNonArrowKind (HsAppTy f a) = do { f' <- repLKind f
1013 ; a' <- repLKind a
1014 ; repKApp f' a'
1015 }
1016 repNonArrowKind (HsListTy k) = do { k' <- repLKind k
1017 ; kcon <- repKList
1018 ; repKApp kcon k'
1019 }
1020 repNonArrowKind (HsTupleTy _ ks) = do { ks' <- mapM repLKind ks
1021 ; kcon <- repKTuple (length ks)
1022 ; repKApps kcon ks'
1023 }
1024 repNonArrowKind k = notHandled "Exotic form of kind" (ppr k)
1025
1026 repRole :: Located (Maybe Role) -> DsM (Core TH.Role)
1027 repRole (L _ (Just Nominal)) = rep2 nominalRName []
1028 repRole (L _ (Just Representational)) = rep2 representationalRName []
1029 repRole (L _ (Just Phantom)) = rep2 phantomRName []
1030 repRole (L _ Nothing) = rep2 inferRName []
1031
1032 -----------------------------------------------------------------------------
1033 -- Splices
1034 -----------------------------------------------------------------------------
1035
1036 repSplice :: HsSplice Name -> DsM (Core a)
1037 -- See Note [How brackets and nested splices are handled] in TcSplice
1038 -- We return a CoreExpr of any old type; the context should know
1039 repSplice (HsTypedSplice n _) = rep_splice n
1040 repSplice (HsUntypedSplice n _) = rep_splice n
1041 repSplice (HsQuasiQuote n _ _ _) = rep_splice n
1042
1043 rep_splice :: Name -> DsM (Core a)
1044 rep_splice splice_name
1045 = do { mb_val <- dsLookupMetaEnv splice_name
1046 ; case mb_val of
1047 Just (DsSplice e) -> do { e' <- dsExpr e
1048 ; return (MkC e') }
1049 _ -> pprPanic "HsSplice" (ppr splice_name) }
1050 -- Should not happen; statically checked
1051
1052 -----------------------------------------------------------------------------
1053 -- Expressions
1054 -----------------------------------------------------------------------------
1055
1056 repLEs :: [LHsExpr Name] -> DsM (Core [TH.ExpQ])
1057 repLEs es = repList expQTyConName repLE es
1058
1059 -- FIXME: some of these panics should be converted into proper error messages
1060 -- unless we can make sure that constructs, which are plainly not
1061 -- supported in TH already lead to error messages at an earlier stage
1062 repLE :: LHsExpr Name -> DsM (Core TH.ExpQ)
1063 repLE (L loc e) = putSrcSpanDs loc (repE e)
1064
1065 repE :: HsExpr Name -> DsM (Core TH.ExpQ)
1066 repE (HsVar x) =
1067 do { mb_val <- dsLookupMetaEnv x
1068 ; case mb_val of
1069 Nothing -> do { str <- globalVar x
1070 ; repVarOrCon x str }
1071 Just (DsBound y) -> repVarOrCon x (coreVar y)
1072 Just (DsSplice e) -> do { e' <- dsExpr e
1073 ; return (MkC e') } }
1074 repE e@(HsIPVar _) = notHandled "Implicit parameters" (ppr e)
1075
1076 repE e@(HsRecFld f) = case f of
1077 Unambiguous _ x -> repE (HsVar x)
1078 Ambiguous{} -> notHandled "Ambiguous record selectors" (ppr e)
1079
1080 -- Remember, we're desugaring renamer output here, so
1081 -- HsOverlit can definitely occur
1082 repE (HsOverLit l) = do { a <- repOverloadedLiteral l; repLit a }
1083 repE (HsLit l) = do { a <- repLiteral l; repLit a }
1084 repE (HsLam (MG { mg_alts = [m] })) = repLambda m
1085 repE (HsLamCase _ (MG { mg_alts = ms }))
1086 = do { ms' <- mapM repMatchTup ms
1087 ; core_ms <- coreList matchQTyConName ms'
1088 ; repLamCase core_ms }
1089 repE (HsApp x y) = do {a <- repLE x; b <- repLE y; repApp a b}
1090
1091 repE (OpApp e1 op _ e2) =
1092 do { arg1 <- repLE e1;
1093 arg2 <- repLE e2;
1094 the_op <- repLE op ;
1095 repInfixApp arg1 the_op arg2 }
1096 repE (NegApp x _) = do
1097 a <- repLE x
1098 negateVar <- lookupOcc negateName >>= repVar
1099 negateVar `repApp` a
1100 repE (HsPar x) = repLE x
1101 repE (SectionL x y) = do { a <- repLE x; b <- repLE y; repSectionL a b }
1102 repE (SectionR x y) = do { a <- repLE x; b <- repLE y; repSectionR a b }
1103 repE (HsCase e (MG { mg_alts = ms }))
1104 = do { arg <- repLE e
1105 ; ms2 <- mapM repMatchTup ms
1106 ; core_ms2 <- coreList matchQTyConName ms2
1107 ; repCaseE arg core_ms2 }
1108 repE (HsIf _ x y z) = do
1109 a <- repLE x
1110 b <- repLE y
1111 c <- repLE z
1112 repCond a b c
1113 repE (HsMultiIf _ alts)
1114 = do { (binds, alts') <- liftM unzip $ mapM repLGRHS alts
1115 ; expr' <- repMultiIf (nonEmptyCoreList alts')
1116 ; wrapGenSyms (concat binds) expr' }
1117 repE (HsLet bs e) = do { (ss,ds) <- repBinds bs
1118 ; e2 <- addBinds ss (repLE e)
1119 ; z <- repLetE ds e2
1120 ; wrapGenSyms ss z }
1121
1122 -- FIXME: I haven't got the types here right yet
1123 repE e@(HsDo ctxt sts _)
1124 | case ctxt of { DoExpr -> True; GhciStmtCtxt -> True; _ -> False }
1125 = do { (ss,zs) <- repLSts sts;
1126 e' <- repDoE (nonEmptyCoreList zs);
1127 wrapGenSyms ss e' }
1128
1129 | ListComp <- ctxt
1130 = do { (ss,zs) <- repLSts sts;
1131 e' <- repComp (nonEmptyCoreList zs);
1132 wrapGenSyms ss e' }
1133
1134 | otherwise
1135 = notHandled "mdo, monad comprehension and [: :]" (ppr e)
1136
1137 repE (ExplicitList _ _ es) = do { xs <- repLEs es; repListExp xs }
1138 repE e@(ExplicitPArr _ _) = notHandled "Parallel arrays" (ppr e)
1139 repE e@(ExplicitTuple es boxed)
1140 | not (all tupArgPresent es) = notHandled "Tuple sections" (ppr e)
1141 | isBoxed boxed = do { xs <- repLEs [e | L _ (Present e) <- es]; repTup xs }
1142 | otherwise = do { xs <- repLEs [e | L _ (Present e) <- es]
1143 ; repUnboxedTup xs }
1144
1145 repE (RecordCon c _ flds)
1146 = do { x <- lookupLOcc c;
1147 fs <- repFields flds;
1148 repRecCon x fs }
1149 repE (RecordUpd e flds _ _ _ _)
1150 = do { x <- repLE e;
1151 fs <- repUpdFields flds;
1152 repRecUpd x fs }
1153
1154 repE (ExprWithTySig e ty _) = do { e1 <- repLE e; t1 <- repLTy ty; repSigExp e1 t1 }
1155 repE (ArithSeq _ _ aseq) =
1156 case aseq of
1157 From e -> do { ds1 <- repLE e; repFrom ds1 }
1158 FromThen e1 e2 -> do
1159 ds1 <- repLE e1
1160 ds2 <- repLE e2
1161 repFromThen ds1 ds2
1162 FromTo e1 e2 -> do
1163 ds1 <- repLE e1
1164 ds2 <- repLE e2
1165 repFromTo ds1 ds2
1166 FromThenTo e1 e2 e3 -> do
1167 ds1 <- repLE e1
1168 ds2 <- repLE e2
1169 ds3 <- repLE e3
1170 repFromThenTo ds1 ds2 ds3
1171
1172 repE (HsSpliceE splice) = repSplice splice
1173 repE (HsStatic e) = repLE e >>= rep2 staticEName . (:[]) . unC
1174 repE (HsUnboundVar name) = do
1175 occ <- occNameLit name
1176 sname <- repNameS occ
1177 repUnboundVar sname
1178
1179 repE e@(PArrSeq {}) = notHandled "Parallel arrays" (ppr e)
1180 repE e@(HsCoreAnn {}) = notHandled "Core annotations" (ppr e)
1181 repE e@(HsSCC {}) = notHandled "Cost centres" (ppr e)
1182 repE e@(HsTickPragma {}) = notHandled "Tick Pragma" (ppr e)
1183 repE e@(HsTcBracketOut {}) = notHandled "TH brackets" (ppr e)
1184 repE e = notHandled "Expression form" (ppr e)
1185
1186 -----------------------------------------------------------------------------
1187 -- Building representations of auxillary structures like Match, Clause, Stmt,
1188
1189 repMatchTup :: LMatch Name (LHsExpr Name) -> DsM (Core TH.MatchQ)
1190 repMatchTup (L _ (Match _ [p] _ (GRHSs guards wheres))) =
1191 do { ss1 <- mkGenSyms (collectPatBinders p)
1192 ; addBinds ss1 $ do {
1193 ; p1 <- repLP p
1194 ; (ss2,ds) <- repBinds wheres
1195 ; addBinds ss2 $ do {
1196 ; gs <- repGuards guards
1197 ; match <- repMatch p1 gs ds
1198 ; wrapGenSyms (ss1++ss2) match }}}
1199 repMatchTup _ = panic "repMatchTup: case alt with more than one arg"
1200
1201 repClauseTup :: LMatch Name (LHsExpr Name) -> DsM (Core TH.ClauseQ)
1202 repClauseTup (L _ (Match _ ps _ (GRHSs guards wheres))) =
1203 do { ss1 <- mkGenSyms (collectPatsBinders ps)
1204 ; addBinds ss1 $ do {
1205 ps1 <- repLPs ps
1206 ; (ss2,ds) <- repBinds wheres
1207 ; addBinds ss2 $ do {
1208 gs <- repGuards guards
1209 ; clause <- repClause ps1 gs ds
1210 ; wrapGenSyms (ss1++ss2) clause }}}
1211
1212 repGuards :: [LGRHS Name (LHsExpr Name)] -> DsM (Core TH.BodyQ)
1213 repGuards [L _ (GRHS [] e)]
1214 = do {a <- repLE e; repNormal a }
1215 repGuards other
1216 = do { zs <- mapM repLGRHS other
1217 ; let (xs, ys) = unzip zs
1218 ; gd <- repGuarded (nonEmptyCoreList ys)
1219 ; wrapGenSyms (concat xs) gd }
1220
1221 repLGRHS :: LGRHS Name (LHsExpr Name) -> DsM ([GenSymBind], (Core (TH.Q (TH.Guard, TH.Exp))))
1222 repLGRHS (L _ (GRHS [L _ (BodyStmt e1 _ _ _)] e2))
1223 = do { guarded <- repLNormalGE e1 e2
1224 ; return ([], guarded) }
1225 repLGRHS (L _ (GRHS ss rhs))
1226 = do { (gs, ss') <- repLSts ss
1227 ; rhs' <- addBinds gs $ repLE rhs
1228 ; guarded <- repPatGE (nonEmptyCoreList ss') rhs'
1229 ; return (gs, guarded) }
1230
1231 repFields :: HsRecordBinds Name -> DsM (Core [TH.Q TH.FieldExp])
1232 repFields (HsRecFields { rec_flds = flds })
1233 = repList fieldExpQTyConName rep_fld flds
1234 where
1235 rep_fld :: LHsRecField Name (LHsExpr Name) -> DsM (Core (TH.Q TH.FieldExp))
1236 rep_fld (L _ fld) = do { fn <- lookupLOcc (hsRecFieldSel fld)
1237 ; e <- repLE (hsRecFieldArg fld)
1238 ; repFieldExp fn e }
1239
1240 repUpdFields :: [LHsRecUpdField Name] -> DsM (Core [TH.Q TH.FieldExp])
1241 repUpdFields = repList fieldExpQTyConName rep_fld
1242 where
1243 rep_fld :: LHsRecUpdField Name -> DsM (Core (TH.Q TH.FieldExp))
1244 rep_fld (L l fld) = case unLoc (hsRecFieldLbl fld) of
1245 Unambiguous _ sel_name -> do { fn <- lookupLOcc (L l sel_name)
1246 ; e <- repLE (hsRecFieldArg fld)
1247 ; repFieldExp fn e }
1248 _ -> notHandled "Ambiguous record updates" (ppr fld)
1249
1250
1251
1252 -----------------------------------------------------------------------------
1253 -- Representing Stmt's is tricky, especially if bound variables
1254 -- shadow each other. Consider: [| do { x <- f 1; x <- f x; g x } |]
1255 -- First gensym new names for every variable in any of the patterns.
1256 -- both static (x'1 and x'2), and dynamic ((gensym "x") and (gensym "y"))
1257 -- if variables didn't shaddow, the static gensym wouldn't be necessary
1258 -- and we could reuse the original names (x and x).
1259 --
1260 -- do { x'1 <- gensym "x"
1261 -- ; x'2 <- gensym "x"
1262 -- ; doE [ BindSt (pvar x'1) [| f 1 |]
1263 -- , BindSt (pvar x'2) [| f x |]
1264 -- , NoBindSt [| g x |]
1265 -- ]
1266 -- }
1267
1268 -- The strategy is to translate a whole list of do-bindings by building a
1269 -- bigger environment, and a bigger set of meta bindings
1270 -- (like: x'1 <- gensym "x" ) and then combining these with the translations
1271 -- of the expressions within the Do
1272
1273 -----------------------------------------------------------------------------
1274 -- The helper function repSts computes the translation of each sub expression
1275 -- and a bunch of prefix bindings denoting the dynamic renaming.
1276
1277 repLSts :: [LStmt Name (LHsExpr Name)] -> DsM ([GenSymBind], [Core TH.StmtQ])
1278 repLSts stmts = repSts (map unLoc stmts)
1279
1280 repSts :: [Stmt Name (LHsExpr Name)] -> DsM ([GenSymBind], [Core TH.StmtQ])
1281 repSts (BindStmt p e _ _ : ss) =
1282 do { e2 <- repLE e
1283 ; ss1 <- mkGenSyms (collectPatBinders p)
1284 ; addBinds ss1 $ do {
1285 ; p1 <- repLP p;
1286 ; (ss2,zs) <- repSts ss
1287 ; z <- repBindSt p1 e2
1288 ; return (ss1++ss2, z : zs) }}
1289 repSts (LetStmt bs : ss) =
1290 do { (ss1,ds) <- repBinds bs
1291 ; z <- repLetSt ds
1292 ; (ss2,zs) <- addBinds ss1 (repSts ss)
1293 ; return (ss1++ss2, z : zs) }
1294 repSts (BodyStmt e _ _ _ : ss) =
1295 do { e2 <- repLE e
1296 ; z <- repNoBindSt e2
1297 ; (ss2,zs) <- repSts ss
1298 ; return (ss2, z : zs) }
1299 repSts (ParStmt stmt_blocks _ _ : ss) =
1300 do { (ss_s, stmt_blocks1) <- mapAndUnzipM rep_stmt_block stmt_blocks
1301 ; let stmt_blocks2 = nonEmptyCoreList stmt_blocks1
1302 ss1 = concat ss_s
1303 ; z <- repParSt stmt_blocks2
1304 ; (ss2, zs) <- addBinds ss1 (repSts ss)
1305 ; return (ss1++ss2, z : zs) }
1306 where
1307 rep_stmt_block :: ParStmtBlock Name Name -> DsM ([GenSymBind], Core [TH.StmtQ])
1308 rep_stmt_block (ParStmtBlock stmts _ _) =
1309 do { (ss1, zs) <- repSts (map unLoc stmts)
1310 ; zs1 <- coreList stmtQTyConName zs
1311 ; return (ss1, zs1) }
1312 repSts [LastStmt e _ _]
1313 = do { e2 <- repLE e
1314 ; z <- repNoBindSt e2
1315 ; return ([], [z]) }
1316 repSts [] = return ([],[])
1317 repSts other = notHandled "Exotic statement" (ppr other)
1318
1319
1320 -----------------------------------------------------------
1321 -- Bindings
1322 -----------------------------------------------------------
1323
1324 repBinds :: HsLocalBinds Name -> DsM ([GenSymBind], Core [TH.DecQ])
1325 repBinds EmptyLocalBinds
1326 = do { core_list <- coreList decQTyConName []
1327 ; return ([], core_list) }
1328
1329 repBinds b@(HsIPBinds _) = notHandled "Implicit parameters" (ppr b)
1330
1331 repBinds (HsValBinds decs)
1332 = do { let { bndrs = hsSigTvBinders decs ++ collectHsValBinders decs }
1333 -- No need to worrry about detailed scopes within
1334 -- the binding group, because we are talking Names
1335 -- here, so we can safely treat it as a mutually
1336 -- recursive group
1337 -- For hsSigTvBinders see Note [Scoped type variables in bindings]
1338 ; ss <- mkGenSyms bndrs
1339 ; prs <- addBinds ss (rep_val_binds decs)
1340 ; core_list <- coreList decQTyConName
1341 (de_loc (sort_by_loc prs))
1342 ; return (ss, core_list) }
1343
1344 rep_val_binds :: HsValBinds Name -> DsM [(SrcSpan, Core TH.DecQ)]
1345 -- Assumes: all the binders of the binding are alrady in the meta-env
1346 rep_val_binds (ValBindsOut binds sigs)
1347 = do { core1 <- rep_binds' (unionManyBags (map snd binds))
1348 ; core2 <- rep_sigs' sigs
1349 ; return (core1 ++ core2) }
1350 rep_val_binds (ValBindsIn _ _)
1351 = panic "rep_val_binds: ValBindsIn"
1352
1353 rep_binds :: LHsBinds Name -> DsM [Core TH.DecQ]
1354 rep_binds binds = do { binds_w_locs <- rep_binds' binds
1355 ; return (de_loc (sort_by_loc binds_w_locs)) }
1356
1357 rep_binds' :: LHsBinds Name -> DsM [(SrcSpan, Core TH.DecQ)]
1358 rep_binds' = mapM rep_bind . bagToList
1359
1360 rep_bind :: LHsBind Name -> DsM (SrcSpan, Core TH.DecQ)
1361 -- Assumes: all the binders of the binding are alrady in the meta-env
1362
1363 -- Note GHC treats declarations of a variable (not a pattern)
1364 -- e.g. x = g 5 as a Fun MonoBinds. This is indicated by a single match
1365 -- with an empty list of patterns
1366 rep_bind (L loc (FunBind
1367 { fun_id = fn,
1368 fun_matches = MG { mg_alts = [L _ (Match _ [] _
1369 (GRHSs guards wheres))] } }))
1370 = do { (ss,wherecore) <- repBinds wheres
1371 ; guardcore <- addBinds ss (repGuards guards)
1372 ; fn' <- lookupLBinder fn
1373 ; p <- repPvar fn'
1374 ; ans <- repVal p guardcore wherecore
1375 ; ans' <- wrapGenSyms ss ans
1376 ; return (loc, ans') }
1377
1378 rep_bind (L loc (FunBind { fun_id = fn, fun_matches = MG { mg_alts = ms } }))
1379 = do { ms1 <- mapM repClauseTup ms
1380 ; fn' <- lookupLBinder fn
1381 ; ans <- repFun fn' (nonEmptyCoreList ms1)
1382 ; return (loc, ans) }
1383
1384 rep_bind (L loc (PatBind { pat_lhs = pat, pat_rhs = GRHSs guards wheres }))
1385 = do { patcore <- repLP pat
1386 ; (ss,wherecore) <- repBinds wheres
1387 ; guardcore <- addBinds ss (repGuards guards)
1388 ; ans <- repVal patcore guardcore wherecore
1389 ; ans' <- wrapGenSyms ss ans
1390 ; return (loc, ans') }
1391
1392 rep_bind (L _ (VarBind { var_id = v, var_rhs = e}))
1393 = do { v' <- lookupBinder v
1394 ; e2 <- repLE e
1395 ; x <- repNormal e2
1396 ; patcore <- repPvar v'
1397 ; empty_decls <- coreList decQTyConName []
1398 ; ans <- repVal patcore x empty_decls
1399 ; return (srcLocSpan (getSrcLoc v), ans) }
1400
1401 rep_bind (L _ (AbsBinds {})) = panic "rep_bind: AbsBinds"
1402 rep_bind (L _ dec@(PatSynBind {})) = notHandled "pattern synonyms" (ppr dec)
1403 -----------------------------------------------------------------------------
1404 -- Since everything in a Bind is mutually recursive we need rename all
1405 -- all the variables simultaneously. For example:
1406 -- [| AndMonoBinds (f x = x + g 2) (g x = f 1 + 2) |] would translate to
1407 -- do { f'1 <- gensym "f"
1408 -- ; g'2 <- gensym "g"
1409 -- ; [ do { x'3 <- gensym "x"; fun f'1 [pvar x'3] [| x + g2 |]},
1410 -- do { x'4 <- gensym "x"; fun g'2 [pvar x'4] [| f 1 + 2 |]}
1411 -- ]}
1412 -- This requires collecting the bindings (f'1 <- gensym "f"), and the
1413 -- environment ( f |-> f'1 ) from each binding, and then unioning them
1414 -- together. As we do this we collect GenSymBinds's which represent the renamed
1415 -- variables bound by the Bindings. In order not to lose track of these
1416 -- representations we build a shadow datatype MB with the same structure as
1417 -- MonoBinds, but which has slots for the representations
1418
1419
1420 -----------------------------------------------------------------------------
1421 -- GHC allows a more general form of lambda abstraction than specified
1422 -- by Haskell 98. In particular it allows guarded lambda's like :
1423 -- (\ x | even x -> 0 | odd x -> 1) at the moment we can't represent this in
1424 -- Haskell Template's Meta.Exp type so we punt if it isn't a simple thing like
1425 -- (\ p1 .. pn -> exp) by causing an error.
1426
1427 repLambda :: LMatch Name (LHsExpr Name) -> DsM (Core TH.ExpQ)
1428 repLambda (L _ (Match _ ps _ (GRHSs [L _ (GRHS [] e)] EmptyLocalBinds)))
1429 = do { let bndrs = collectPatsBinders ps ;
1430 ; ss <- mkGenSyms bndrs
1431 ; lam <- addBinds ss (
1432 do { xs <- repLPs ps; body <- repLE e; repLam xs body })
1433 ; wrapGenSyms ss lam }
1434
1435 repLambda (L _ m) = notHandled "Guarded labmdas" (pprMatch (LambdaExpr :: HsMatchContext Name) m)
1436
1437
1438 -----------------------------------------------------------------------------
1439 -- Patterns
1440 -- repP deals with patterns. It assumes that we have already
1441 -- walked over the pattern(s) once to collect the binders, and
1442 -- have extended the environment. So every pattern-bound
1443 -- variable should already appear in the environment.
1444
1445 -- Process a list of patterns
1446 repLPs :: [LPat Name] -> DsM (Core [TH.PatQ])
1447 repLPs ps = repList patQTyConName repLP ps
1448
1449 repLP :: LPat Name -> DsM (Core TH.PatQ)
1450 repLP (L _ p) = repP p
1451
1452 repP :: Pat Name -> DsM (Core TH.PatQ)
1453 repP (WildPat _) = repPwild
1454 repP (LitPat l) = do { l2 <- repLiteral l; repPlit l2 }
1455 repP (VarPat x) = do { x' <- lookupBinder x; repPvar x' }
1456 repP (LazyPat p) = do { p1 <- repLP p; repPtilde p1 }
1457 repP (BangPat p) = do { p1 <- repLP p; repPbang p1 }
1458 repP (AsPat x p) = do { x' <- lookupLBinder x; p1 <- repLP p; repPaspat x' p1 }
1459 repP (ParPat p) = repLP p
1460 repP (ListPat ps _ Nothing) = do { qs <- repLPs ps; repPlist qs }
1461 repP (ListPat ps ty1 (Just (_,e))) = do { p <- repP (ListPat ps ty1 Nothing); e' <- repE e; repPview e' p}
1462 repP (TuplePat ps boxed _)
1463 | isBoxed boxed = do { qs <- repLPs ps; repPtup qs }
1464 | otherwise = do { qs <- repLPs ps; repPunboxedTup qs }
1465 repP (ConPatIn dc details)
1466 = do { con_str <- lookupLOcc dc
1467 ; case details of
1468 PrefixCon ps -> do { qs <- repLPs ps; repPcon con_str qs }
1469 RecCon rec -> do { fps <- repList fieldPatQTyConName rep_fld (rec_flds rec)
1470 ; repPrec con_str fps }
1471 InfixCon p1 p2 -> do { p1' <- repLP p1;
1472 p2' <- repLP p2;
1473 repPinfix p1' con_str p2' }
1474 }
1475 where
1476 rep_fld :: LHsRecField Name (LPat Name) -> DsM (Core (TH.Name,TH.PatQ))
1477 rep_fld (L _ fld) = do { MkC v <- lookupLOcc (hsRecFieldSel fld)
1478 ; MkC p <- repLP (hsRecFieldArg fld)
1479 ; rep2 fieldPatName [v,p] }
1480
1481 repP (NPat (L _ l) Nothing _) = do { a <- repOverloadedLiteral l; repPlit a }
1482 repP (ViewPat e p _) = do { e' <- repLE e; p' <- repLP p; repPview e' p' }
1483 repP p@(NPat _ (Just _) _) = notHandled "Negative overloaded patterns" (ppr p)
1484 repP p@(SigPatIn {}) = notHandled "Type signatures in patterns" (ppr p)
1485 -- The problem is to do with scoped type variables.
1486 -- To implement them, we have to implement the scoping rules
1487 -- here in DsMeta, and I don't want to do that today!
1488 -- do { p' <- repLP p; t' <- repLTy t; repPsig p' t' }
1489 -- repPsig :: Core TH.PatQ -> Core TH.TypeQ -> DsM (Core TH.PatQ)
1490 -- repPsig (MkC p) (MkC t) = rep2 sigPName [p, t]
1491
1492 repP (SplicePat splice) = repSplice splice
1493
1494 repP other = notHandled "Exotic pattern" (ppr other)
1495
1496 ----------------------------------------------------------
1497 -- Declaration ordering helpers
1498
1499 sort_by_loc :: [(SrcSpan, a)] -> [(SrcSpan, a)]
1500 sort_by_loc xs = sortBy comp xs
1501 where comp x y = compare (fst x) (fst y)
1502
1503 de_loc :: [(a, b)] -> [b]
1504 de_loc = map snd
1505
1506 ----------------------------------------------------------
1507 -- The meta-environment
1508
1509 -- A name/identifier association for fresh names of locally bound entities
1510 type GenSymBind = (Name, Id) -- Gensym the string and bind it to the Id
1511 -- I.e. (x, x_id) means
1512 -- let x_id = gensym "x" in ...
1513
1514 -- Generate a fresh name for a locally bound entity
1515
1516 mkGenSyms :: [Name] -> DsM [GenSymBind]
1517 -- We can use the existing name. For example:
1518 -- [| \x_77 -> x_77 + x_77 |]
1519 -- desugars to
1520 -- do { x_77 <- genSym "x"; .... }
1521 -- We use the same x_77 in the desugared program, but with the type Bndr
1522 -- instead of Int
1523 --
1524 -- We do make it an Internal name, though (hence localiseName)
1525 --
1526 -- Nevertheless, it's monadic because we have to generate nameTy
1527 mkGenSyms ns = do { var_ty <- lookupType nameTyConName
1528 ; return [(nm, mkLocalId (localiseName nm) var_ty) | nm <- ns] }
1529
1530
1531 addBinds :: [GenSymBind] -> DsM a -> DsM a
1532 -- Add a list of fresh names for locally bound entities to the
1533 -- meta environment (which is part of the state carried around
1534 -- by the desugarer monad)
1535 addBinds bs m = dsExtendMetaEnv (mkNameEnv [(n,DsBound id) | (n,id) <- bs]) m
1536
1537 dupBinder :: (Name, Name) -> DsM (Name, DsMetaVal)
1538 dupBinder (new, old)
1539 = do { mb_val <- dsLookupMetaEnv old
1540 ; case mb_val of
1541 Just val -> return (new, val)
1542 Nothing -> pprPanic "dupBinder" (ppr old) }
1543
1544 -- Look up a locally bound name
1545 --
1546 lookupLBinder :: Located Name -> DsM (Core TH.Name)
1547 lookupLBinder (L _ n) = lookupBinder n
1548
1549 lookupBinder :: Name -> DsM (Core TH.Name)
1550 lookupBinder = lookupOcc
1551 -- Binders are brought into scope before the pattern or what-not is
1552 -- desugared. Moreover, in instance declaration the binder of a method
1553 -- will be the selector Id and hence a global; so we need the
1554 -- globalVar case of lookupOcc
1555
1556 -- Look up a name that is either locally bound or a global name
1557 --
1558 -- * If it is a global name, generate the "original name" representation (ie,
1559 -- the <module>:<name> form) for the associated entity
1560 --
1561 lookupLOcc :: Located Name -> DsM (Core TH.Name)
1562 -- Lookup an occurrence; it can't be a splice.
1563 -- Use the in-scope bindings if they exist
1564 lookupLOcc (L _ n) = lookupOcc n
1565
1566 lookupOcc :: Name -> DsM (Core TH.Name)
1567 lookupOcc n
1568 = do { mb_val <- dsLookupMetaEnv n ;
1569 case mb_val of
1570 Nothing -> globalVar n
1571 Just (DsBound x) -> return (coreVar x)
1572 Just (DsSplice _) -> pprPanic "repE:lookupOcc" (ppr n)
1573 }
1574
1575 globalVar :: Name -> DsM (Core TH.Name)
1576 -- Not bound by the meta-env
1577 -- Could be top-level; or could be local
1578 -- f x = $(g [| x |])
1579 -- Here the x will be local
1580 globalVar name
1581 | isExternalName name
1582 = do { MkC mod <- coreStringLit name_mod
1583 ; MkC pkg <- coreStringLit name_pkg
1584 ; MkC occ <- nameLit name
1585 ; rep2 mk_varg [pkg,mod,occ] }
1586 | otherwise
1587 = do { MkC occ <- nameLit name
1588 ; MkC uni <- coreIntLit (getKey (getUnique name))
1589 ; rep2 mkNameLName [occ,uni] }
1590 where
1591 mod = ASSERT( isExternalName name) nameModule name
1592 name_mod = moduleNameString (moduleName mod)
1593 name_pkg = unitIdString (moduleUnitId mod)
1594 name_occ = nameOccName name
1595 mk_varg | OccName.isDataOcc name_occ = mkNameG_dName
1596 | OccName.isVarOcc name_occ = mkNameG_vName
1597 | OccName.isTcOcc name_occ = mkNameG_tcName
1598 | otherwise = pprPanic "DsMeta.globalVar" (ppr name)
1599
1600 lookupType :: Name -- Name of type constructor (e.g. TH.ExpQ)
1601 -> DsM Type -- The type
1602 lookupType tc_name = do { tc <- dsLookupTyCon tc_name ;
1603 return (mkTyConApp tc []) }
1604
1605 wrapGenSyms :: [GenSymBind]
1606 -> Core (TH.Q a) -> DsM (Core (TH.Q a))
1607 -- wrapGenSyms [(nm1,id1), (nm2,id2)] y
1608 -- --> bindQ (gensym nm1) (\ id1 ->
1609 -- bindQ (gensym nm2 (\ id2 ->
1610 -- y))
1611
1612 wrapGenSyms binds body@(MkC b)
1613 = do { var_ty <- lookupType nameTyConName
1614 ; go var_ty binds }
1615 where
1616 [elt_ty] = tcTyConAppArgs (exprType b)
1617 -- b :: Q a, so we can get the type 'a' by looking at the
1618 -- argument type. NB: this relies on Q being a data/newtype,
1619 -- not a type synonym
1620
1621 go _ [] = return body
1622 go var_ty ((name,id) : binds)
1623 = do { MkC body' <- go var_ty binds
1624 ; lit_str <- nameLit name
1625 ; gensym_app <- repGensym lit_str
1626 ; repBindQ var_ty elt_ty
1627 gensym_app (MkC (Lam id body')) }
1628
1629 nameLit :: Name -> DsM (Core String)
1630 nameLit n = coreStringLit (occNameString (nameOccName n))
1631
1632 occNameLit :: OccName -> DsM (Core String)
1633 occNameLit name = coreStringLit (occNameString name)
1634
1635
1636 -- %*********************************************************************
1637 -- %* *
1638 -- Constructing code
1639 -- %* *
1640 -- %*********************************************************************
1641
1642 -----------------------------------------------------------------------------
1643 -- PHANTOM TYPES for consistency. In order to make sure we do this correct
1644 -- we invent a new datatype which uses phantom types.
1645
1646 newtype Core a = MkC CoreExpr
1647 unC :: Core a -> CoreExpr
1648 unC (MkC x) = x
1649
1650 rep2 :: Name -> [ CoreExpr ] -> DsM (Core a)
1651 rep2 n xs = do { id <- dsLookupGlobalId n
1652 ; return (MkC (foldl App (Var id) xs)) }
1653
1654 dataCon' :: Name -> [CoreExpr] -> DsM (Core a)
1655 dataCon' n args = do { id <- dsLookupDataCon n
1656 ; return $ MkC $ mkCoreConApps id args }
1657
1658 dataCon :: Name -> DsM (Core a)
1659 dataCon n = dataCon' n []
1660
1661 -- Then we make "repConstructors" which use the phantom types for each of the
1662 -- smart constructors of the Meta.Meta datatypes.
1663
1664
1665 -- %*********************************************************************
1666 -- %* *
1667 -- The 'smart constructors'
1668 -- %* *
1669 -- %*********************************************************************
1670
1671 --------------- Patterns -----------------
1672 repPlit :: Core TH.Lit -> DsM (Core TH.PatQ)
1673 repPlit (MkC l) = rep2 litPName [l]
1674
1675 repPvar :: Core TH.Name -> DsM (Core TH.PatQ)
1676 repPvar (MkC s) = rep2 varPName [s]
1677
1678 repPtup :: Core [TH.PatQ] -> DsM (Core TH.PatQ)
1679 repPtup (MkC ps) = rep2 tupPName [ps]
1680
1681 repPunboxedTup :: Core [TH.PatQ] -> DsM (Core TH.PatQ)
1682 repPunboxedTup (MkC ps) = rep2 unboxedTupPName [ps]
1683
1684 repPcon :: Core TH.Name -> Core [TH.PatQ] -> DsM (Core TH.PatQ)
1685 repPcon (MkC s) (MkC ps) = rep2 conPName [s, ps]
1686
1687 repPrec :: Core TH.Name -> Core [(TH.Name,TH.PatQ)] -> DsM (Core TH.PatQ)
1688 repPrec (MkC c) (MkC rps) = rep2 recPName [c,rps]
1689
1690 repPinfix :: Core TH.PatQ -> Core TH.Name -> Core TH.PatQ -> DsM (Core TH.PatQ)
1691 repPinfix (MkC p1) (MkC n) (MkC p2) = rep2 infixPName [p1, n, p2]
1692
1693 repPtilde :: Core TH.PatQ -> DsM (Core TH.PatQ)
1694 repPtilde (MkC p) = rep2 tildePName [p]
1695
1696 repPbang :: Core TH.PatQ -> DsM (Core TH.PatQ)
1697 repPbang (MkC p) = rep2 bangPName [p]
1698
1699 repPaspat :: Core TH.Name -> Core TH.PatQ -> DsM (Core TH.PatQ)
1700 repPaspat (MkC s) (MkC p) = rep2 asPName [s, p]
1701
1702 repPwild :: DsM (Core TH.PatQ)
1703 repPwild = rep2 wildPName []
1704
1705 repPlist :: Core [TH.PatQ] -> DsM (Core TH.PatQ)
1706 repPlist (MkC ps) = rep2 listPName [ps]
1707
1708 repPview :: Core TH.ExpQ -> Core TH.PatQ -> DsM (Core TH.PatQ)
1709 repPview (MkC e) (MkC p) = rep2 viewPName [e,p]
1710
1711 --------------- Expressions -----------------
1712 repVarOrCon :: Name -> Core TH.Name -> DsM (Core TH.ExpQ)
1713 repVarOrCon vc str | isDataOcc (nameOccName vc) = repCon str
1714 | otherwise = repVar str
1715
1716 repVar :: Core TH.Name -> DsM (Core TH.ExpQ)
1717 repVar (MkC s) = rep2 varEName [s]
1718
1719 repCon :: Core TH.Name -> DsM (Core TH.ExpQ)
1720 repCon (MkC s) = rep2 conEName [s]
1721
1722 repLit :: Core TH.Lit -> DsM (Core TH.ExpQ)
1723 repLit (MkC c) = rep2 litEName [c]
1724
1725 repApp :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1726 repApp (MkC x) (MkC y) = rep2 appEName [x,y]
1727
1728 repLam :: Core [TH.PatQ] -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1729 repLam (MkC ps) (MkC e) = rep2 lamEName [ps, e]
1730
1731 repLamCase :: Core [TH.MatchQ] -> DsM (Core TH.ExpQ)
1732 repLamCase (MkC ms) = rep2 lamCaseEName [ms]
1733
1734 repTup :: Core [TH.ExpQ] -> DsM (Core TH.ExpQ)
1735 repTup (MkC es) = rep2 tupEName [es]
1736
1737 repUnboxedTup :: Core [TH.ExpQ] -> DsM (Core TH.ExpQ)
1738 repUnboxedTup (MkC es) = rep2 unboxedTupEName [es]
1739
1740 repCond :: Core TH.ExpQ -> Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1741 repCond (MkC x) (MkC y) (MkC z) = rep2 condEName [x,y,z]
1742
1743 repMultiIf :: Core [TH.Q (TH.Guard, TH.Exp)] -> DsM (Core TH.ExpQ)
1744 repMultiIf (MkC alts) = rep2 multiIfEName [alts]
1745
1746 repLetE :: Core [TH.DecQ] -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1747 repLetE (MkC ds) (MkC e) = rep2 letEName [ds, e]
1748
1749 repCaseE :: Core TH.ExpQ -> Core [TH.MatchQ] -> DsM( Core TH.ExpQ)
1750 repCaseE (MkC e) (MkC ms) = rep2 caseEName [e, ms]
1751
1752 repDoE :: Core [TH.StmtQ] -> DsM (Core TH.ExpQ)
1753 repDoE (MkC ss) = rep2 doEName [ss]
1754
1755 repComp :: Core [TH.StmtQ] -> DsM (Core TH.ExpQ)
1756 repComp (MkC ss) = rep2 compEName [ss]
1757
1758 repListExp :: Core [TH.ExpQ] -> DsM (Core TH.ExpQ)
1759 repListExp (MkC es) = rep2 listEName [es]
1760
1761 repSigExp :: Core TH.ExpQ -> Core TH.TypeQ -> DsM (Core TH.ExpQ)
1762 repSigExp (MkC e) (MkC t) = rep2 sigEName [e,t]
1763
1764 repRecCon :: Core TH.Name -> Core [TH.Q TH.FieldExp]-> DsM (Core TH.ExpQ)
1765 repRecCon (MkC c) (MkC fs) = rep2 recConEName [c,fs]
1766
1767 repRecUpd :: Core TH.ExpQ -> Core [TH.Q TH.FieldExp] -> DsM (Core TH.ExpQ)
1768 repRecUpd (MkC e) (MkC fs) = rep2 recUpdEName [e,fs]
1769
1770 repFieldExp :: Core TH.Name -> Core TH.ExpQ -> DsM (Core (TH.Q TH.FieldExp))
1771 repFieldExp (MkC n) (MkC x) = rep2 fieldExpName [n,x]
1772
1773 repInfixApp :: Core TH.ExpQ -> Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1774 repInfixApp (MkC x) (MkC y) (MkC z) = rep2 infixAppName [x,y,z]
1775
1776 repSectionL :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1777 repSectionL (MkC x) (MkC y) = rep2 sectionLName [x,y]
1778
1779 repSectionR :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1780 repSectionR (MkC x) (MkC y) = rep2 sectionRName [x,y]
1781
1782 ------------ Right hand sides (guarded expressions) ----
1783 repGuarded :: Core [TH.Q (TH.Guard, TH.Exp)] -> DsM (Core TH.BodyQ)
1784 repGuarded (MkC pairs) = rep2 guardedBName [pairs]
1785
1786 repNormal :: Core TH.ExpQ -> DsM (Core TH.BodyQ)
1787 repNormal (MkC e) = rep2 normalBName [e]
1788
1789 ------------ Guards ----
1790 repLNormalGE :: LHsExpr Name -> LHsExpr Name -> DsM (Core (TH.Q (TH.Guard, TH.Exp)))
1791 repLNormalGE g e = do g' <- repLE g
1792 e' <- repLE e
1793 repNormalGE g' e'
1794
1795 repNormalGE :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core (TH.Q (TH.Guard, TH.Exp)))
1796 repNormalGE (MkC g) (MkC e) = rep2 normalGEName [g, e]
1797
1798 repPatGE :: Core [TH.StmtQ] -> Core TH.ExpQ -> DsM (Core (TH.Q (TH.Guard, TH.Exp)))
1799 repPatGE (MkC ss) (MkC e) = rep2 patGEName [ss, e]
1800
1801 ------------- Stmts -------------------
1802 repBindSt :: Core TH.PatQ -> Core TH.ExpQ -> DsM (Core TH.StmtQ)
1803 repBindSt (MkC p) (MkC e) = rep2 bindSName [p,e]
1804
1805 repLetSt :: Core [TH.DecQ] -> DsM (Core TH.StmtQ)
1806 repLetSt (MkC ds) = rep2 letSName [ds]
1807
1808 repNoBindSt :: Core TH.ExpQ -> DsM (Core TH.StmtQ)
1809 repNoBindSt (MkC e) = rep2 noBindSName [e]
1810
1811 repParSt :: Core [[TH.StmtQ]] -> DsM (Core TH.StmtQ)
1812 repParSt (MkC sss) = rep2 parSName [sss]
1813
1814 -------------- Range (Arithmetic sequences) -----------
1815 repFrom :: Core TH.ExpQ -> DsM (Core TH.ExpQ)
1816 repFrom (MkC x) = rep2 fromEName [x]
1817
1818 repFromThen :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1819 repFromThen (MkC x) (MkC y) = rep2 fromThenEName [x,y]
1820
1821 repFromTo :: Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1822 repFromTo (MkC x) (MkC y) = rep2 fromToEName [x,y]
1823
1824 repFromThenTo :: Core TH.ExpQ -> Core TH.ExpQ -> Core TH.ExpQ -> DsM (Core TH.ExpQ)
1825 repFromThenTo (MkC x) (MkC y) (MkC z) = rep2 fromThenToEName [x,y,z]
1826
1827 ------------ Match and Clause Tuples -----------
1828 repMatch :: Core TH.PatQ -> Core TH.BodyQ -> Core [TH.DecQ] -> DsM (Core TH.MatchQ)
1829 repMatch (MkC p) (MkC bod) (MkC ds) = rep2 matchName [p, bod, ds]
1830
1831 repClause :: Core [TH.PatQ] -> Core TH.BodyQ -> Core [TH.DecQ] -> DsM (Core TH.ClauseQ)
1832 repClause (MkC ps) (MkC bod) (MkC ds) = rep2 clauseName [ps, bod, ds]
1833
1834 -------------- Dec -----------------------------
1835 repVal :: Core TH.PatQ -> Core TH.BodyQ -> Core [TH.DecQ] -> DsM (Core TH.DecQ)
1836 repVal (MkC p) (MkC b) (MkC ds) = rep2 valDName [p, b, ds]
1837
1838 repFun :: Core TH.Name -> Core [TH.ClauseQ] -> DsM (Core TH.DecQ)
1839 repFun (MkC nm) (MkC b) = rep2 funDName [nm, b]
1840
1841 repData :: Core TH.CxtQ -> Core TH.Name -> Core [TH.TyVarBndr]
1842 -> Maybe (Core [TH.TypeQ])
1843 -> Core [TH.ConQ] -> Core [TH.Name] -> DsM (Core TH.DecQ)
1844 repData (MkC cxt) (MkC nm) (MkC tvs) Nothing (MkC cons) (MkC derivs)
1845 = rep2 dataDName [cxt, nm, tvs, cons, derivs]
1846 repData (MkC cxt) (MkC nm) (MkC _) (Just (MkC tys)) (MkC cons) (MkC derivs)
1847 = rep2 dataInstDName [cxt, nm, tys, cons, derivs]
1848
1849 repNewtype :: Core TH.CxtQ -> Core TH.Name -> Core [TH.TyVarBndr]
1850 -> Maybe (Core [TH.TypeQ])
1851 -> Core TH.ConQ -> Core [TH.Name] -> DsM (Core TH.DecQ)
1852 repNewtype (MkC cxt) (MkC nm) (MkC tvs) Nothing (MkC con) (MkC derivs)
1853 = rep2 newtypeDName [cxt, nm, tvs, con, derivs]
1854 repNewtype (MkC cxt) (MkC nm) (MkC _) (Just (MkC tys)) (MkC con) (MkC derivs)
1855 = rep2 newtypeInstDName [cxt, nm, tys, con, derivs]
1856
1857 repTySyn :: Core TH.Name -> Core [TH.TyVarBndr]
1858 -> Core TH.TypeQ -> DsM (Core TH.DecQ)
1859 repTySyn (MkC nm) (MkC tvs) (MkC rhs)
1860 = rep2 tySynDName [nm, tvs, rhs]
1861
1862 repInst :: Core TH.CxtQ -> Core TH.TypeQ -> Core [TH.DecQ] -> DsM (Core TH.DecQ)
1863 repInst (MkC cxt) (MkC ty) (MkC ds) = rep2 instanceDName [cxt, ty, ds]
1864
1865 repClass :: Core TH.CxtQ -> Core TH.Name -> Core [TH.TyVarBndr]
1866 -> Core [TH.FunDep] -> Core [TH.DecQ]
1867 -> DsM (Core TH.DecQ)
1868 repClass (MkC cxt) (MkC cls) (MkC tvs) (MkC fds) (MkC ds)
1869 = rep2 classDName [cxt, cls, tvs, fds, ds]
1870
1871 repDeriv :: Core TH.CxtQ -> Core TH.TypeQ -> DsM (Core TH.DecQ)
1872 repDeriv (MkC cxt) (MkC ty) = rep2 standaloneDerivDName [cxt, ty]
1873
1874 repPragInl :: Core TH.Name -> Core TH.Inline -> Core TH.RuleMatch
1875 -> Core TH.Phases -> DsM (Core TH.DecQ)
1876 repPragInl (MkC nm) (MkC inline) (MkC rm) (MkC phases)
1877 = rep2 pragInlDName [nm, inline, rm, phases]
1878
1879 repPragSpec :: Core TH.Name -> Core TH.TypeQ -> Core TH.Phases
1880 -> DsM (Core TH.DecQ)
1881 repPragSpec (MkC nm) (MkC ty) (MkC phases)
1882 = rep2 pragSpecDName [nm, ty, phases]
1883
1884 repPragSpecInl :: Core TH.Name -> Core TH.TypeQ -> Core TH.Inline
1885 -> Core TH.Phases -> DsM (Core TH.DecQ)
1886 repPragSpecInl (MkC nm) (MkC ty) (MkC inline) (MkC phases)
1887 = rep2 pragSpecInlDName [nm, ty, inline, phases]
1888
1889 repPragSpecInst :: Core TH.TypeQ -> DsM (Core TH.DecQ)
1890 repPragSpecInst (MkC ty) = rep2 pragSpecInstDName [ty]
1891
1892 repPragRule :: Core String -> Core [TH.RuleBndrQ] -> Core TH.ExpQ
1893 -> Core TH.ExpQ -> Core TH.Phases -> DsM (Core TH.DecQ)
1894 repPragRule (MkC nm) (MkC bndrs) (MkC lhs) (MkC rhs) (MkC phases)
1895 = rep2 pragRuleDName [nm, bndrs, lhs, rhs, phases]
1896
1897 repPragAnn :: Core TH.AnnTarget -> Core TH.ExpQ -> DsM (Core TH.DecQ)
1898 repPragAnn (MkC targ) (MkC e) = rep2 pragAnnDName [targ, e]
1899
1900 repTySynInst :: Core TH.Name -> Core TH.TySynEqnQ -> DsM (Core TH.DecQ)
1901 repTySynInst (MkC nm) (MkC eqn)
1902 = rep2 tySynInstDName [nm, eqn]
1903
1904 repDataFamilyD :: Core TH.Name -> Core [TH.TyVarBndr]
1905 -> Core (Maybe TH.Kind) -> DsM (Core TH.DecQ)
1906 repDataFamilyD (MkC nm) (MkC tvs) (MkC kind)
1907 = rep2 dataFamilyDName [nm, tvs, kind]
1908
1909 repOpenFamilyD :: Core TH.Name
1910 -> Core [TH.TyVarBndr]
1911 -> Core TH.FamilyResultSig
1912 -> Core (Maybe TH.InjectivityAnn)
1913 -> DsM (Core TH.DecQ)
1914 repOpenFamilyD (MkC nm) (MkC tvs) (MkC result) (MkC inj)
1915 = rep2 openTypeFamilyDName [nm, tvs, result, inj]
1916
1917 repClosedFamilyD :: Core TH.Name
1918 -> Core [TH.TyVarBndr]
1919 -> Core TH.FamilyResultSig
1920 -> Core (Maybe TH.InjectivityAnn)
1921 -> Core [TH.TySynEqnQ]
1922 -> DsM (Core TH.DecQ)
1923 repClosedFamilyD (MkC nm) (MkC tvs) (MkC res) (MkC inj) (MkC eqns)
1924 = rep2 closedTypeFamilyDName [nm, tvs, res, inj, eqns]
1925
1926 repTySynEqn :: Core [TH.TypeQ] -> Core TH.TypeQ -> DsM (Core TH.TySynEqnQ)
1927 repTySynEqn (MkC lhs) (MkC rhs)
1928 = rep2 tySynEqnName [lhs, rhs]
1929
1930 repRoleAnnotD :: Core TH.Name -> Core [TH.Role] -> DsM (Core TH.DecQ)
1931 repRoleAnnotD (MkC n) (MkC roles) = rep2 roleAnnotDName [n, roles]
1932
1933 repFunDep :: Core [TH.Name] -> Core [TH.Name] -> DsM (Core TH.FunDep)
1934 repFunDep (MkC xs) (MkC ys) = rep2 funDepName [xs, ys]
1935
1936 repProto :: Name -> Core TH.Name -> Core TH.TypeQ -> DsM (Core TH.DecQ)
1937 repProto mk_sig (MkC s) (MkC ty) = rep2 mk_sig [s, ty]
1938
1939 repCtxt :: Core [TH.PredQ] -> DsM (Core TH.CxtQ)
1940 repCtxt (MkC tys) = rep2 cxtName [tys]
1941
1942 repConstr :: Core TH.Name -> HsConDeclDetails Name
1943 -> DsM (Core TH.ConQ)
1944 repConstr con (PrefixCon ps)
1945 = do arg_tys <- repList strictTypeQTyConName repBangTy ps
1946 rep2 normalCName [unC con, unC arg_tys]
1947
1948 repConstr con (RecCon (L _ ips))
1949 = do { args <- concatMapM rep_ip ips
1950 ; arg_vtys <- coreList varStrictTypeQTyConName args
1951 ; rep2 recCName [unC con, unC arg_vtys] }
1952 where
1953 rep_ip (L _ ip) = mapM (rep_one_ip (cd_fld_type ip)) (cd_fld_names ip)
1954
1955 rep_one_ip :: LBangType Name -> LFieldOcc Name -> DsM (Core a)
1956 rep_one_ip t n = do { MkC v <- lookupOcc (selectorFieldOcc $ unLoc n)
1957 ; MkC ty <- repBangTy t
1958 ; rep2 varStrictTypeName [v,ty] }
1959
1960 repConstr con (InfixCon st1 st2)
1961 = do arg1 <- repBangTy st1
1962 arg2 <- repBangTy st2
1963 rep2 infixCName [unC arg1, unC con, unC arg2]
1964
1965 ------------ Types -------------------
1966
1967 repTForall :: Core [TH.TyVarBndr] -> Core TH.CxtQ -> Core TH.TypeQ
1968 -> DsM (Core TH.TypeQ)
1969 repTForall (MkC tvars) (MkC ctxt) (MkC ty)
1970 = rep2 forallTName [tvars, ctxt, ty]
1971
1972 repTvar :: Core TH.Name -> DsM (Core TH.TypeQ)
1973 repTvar (MkC s) = rep2 varTName [s]
1974
1975 repTapp :: Core TH.TypeQ -> Core TH.TypeQ -> DsM (Core TH.TypeQ)
1976 repTapp (MkC t1) (MkC t2) = rep2 appTName [t1, t2]
1977
1978 repTapps :: Core TH.TypeQ -> [Core TH.TypeQ] -> DsM (Core TH.TypeQ)
1979 repTapps f [] = return f
1980 repTapps f (t:ts) = do { f1 <- repTapp f t; repTapps f1 ts }
1981
1982 repTSig :: Core TH.TypeQ -> Core TH.Kind -> DsM (Core TH.TypeQ)
1983 repTSig (MkC ty) (MkC ki) = rep2 sigTName [ty, ki]
1984
1985 repTequality :: DsM (Core TH.TypeQ)
1986 repTequality = rep2 equalityTName []
1987
1988 repTPromotedList :: [Core TH.TypeQ] -> DsM (Core TH.TypeQ)
1989 repTPromotedList [] = repPromotedNilTyCon
1990 repTPromotedList (t:ts) = do { tcon <- repPromotedConsTyCon
1991 ; f <- repTapp tcon t
1992 ; t' <- repTPromotedList ts
1993 ; repTapp f t'
1994 }
1995
1996 repTLit :: Core TH.TyLitQ -> DsM (Core TH.TypeQ)
1997 repTLit (MkC lit) = rep2 litTName [lit]
1998
1999 repTWildCard :: DsM (Core TH.TypeQ)
2000 repTWildCard = rep2 wildCardTName []
2001
2002 repTNamedWildCard :: Core TH.Name -> DsM (Core TH.TypeQ)
2003 repTNamedWildCard (MkC s) = rep2 namedWildCardTName [s]
2004
2005
2006 --------- Type constructors --------------
2007
2008 repNamedTyCon :: Core TH.Name -> DsM (Core TH.TypeQ)
2009 repNamedTyCon (MkC s) = rep2 conTName [s]
2010
2011 repTupleTyCon :: Int -> DsM (Core TH.TypeQ)
2012 -- Note: not Core Int; it's easier to be direct here
2013 repTupleTyCon i = do dflags <- getDynFlags
2014 rep2 tupleTName [mkIntExprInt dflags i]
2015
2016 repUnboxedTupleTyCon :: Int -> DsM (Core TH.TypeQ)
2017 -- Note: not Core Int; it's easier to be direct here
2018 repUnboxedTupleTyCon i = do dflags <- getDynFlags
2019 rep2 unboxedTupleTName [mkIntExprInt dflags i]
2020
2021 repArrowTyCon :: DsM (Core TH.TypeQ)
2022 repArrowTyCon = rep2 arrowTName []
2023
2024 repListTyCon :: DsM (Core TH.TypeQ)
2025 repListTyCon = rep2 listTName []
2026
2027 repPromotedTyCon :: Core TH.Name -> DsM (Core TH.TypeQ)
2028 repPromotedTyCon (MkC s) = rep2 promotedTName [s]
2029
2030 repPromotedTupleTyCon :: Int -> DsM (Core TH.TypeQ)
2031 repPromotedTupleTyCon i = do dflags <- getDynFlags
2032 rep2 promotedTupleTName [mkIntExprInt dflags i]
2033
2034 repPromotedNilTyCon :: DsM (Core TH.TypeQ)
2035 repPromotedNilTyCon = rep2 promotedNilTName []
2036
2037 repPromotedConsTyCon :: DsM (Core TH.TypeQ)
2038 repPromotedConsTyCon = rep2 promotedConsTName []
2039
2040 ------------ Kinds -------------------
2041
2042 repPlainTV :: Core TH.Name -> DsM (Core TH.TyVarBndr)
2043 repPlainTV (MkC nm) = rep2 plainTVName [nm]
2044
2045 repKindedTV :: Core TH.Name -> Core TH.Kind -> DsM (Core TH.TyVarBndr)
2046 repKindedTV (MkC nm) (MkC ki) = rep2 kindedTVName [nm, ki]
2047
2048 repKVar :: Core TH.Name -> DsM (Core TH.Kind)
2049 repKVar (MkC s) = rep2 varKName [s]
2050
2051 repKCon :: Core TH.Name -> DsM (Core TH.Kind)
2052 repKCon (MkC s) = rep2 conKName [s]
2053
2054 repKTuple :: Int -> DsM (Core TH.Kind)
2055 repKTuple i = do dflags <- getDynFlags
2056 rep2 tupleKName [mkIntExprInt dflags i]
2057
2058 repKArrow :: DsM (Core TH.Kind)
2059 repKArrow = rep2 arrowKName []
2060
2061 repKList :: DsM (Core TH.Kind)
2062 repKList = rep2 listKName []
2063
2064 repKApp :: Core TH.Kind -> Core TH.Kind -> DsM (Core TH.Kind)
2065 repKApp (MkC k1) (MkC k2) = rep2 appKName [k1, k2]
2066
2067 repKApps :: Core TH.Kind -> [Core TH.Kind] -> DsM (Core TH.Kind)
2068 repKApps f [] = return f
2069 repKApps f (k:ks) = do { f' <- repKApp f k; repKApps f' ks }
2070
2071 repKStar :: DsM (Core TH.Kind)
2072 repKStar = rep2 starKName []
2073
2074 repKConstraint :: DsM (Core TH.Kind)
2075 repKConstraint = rep2 constraintKName []
2076
2077 ----------------------------------------------------------
2078 -- Type family result signature
2079
2080 repNoSig :: DsM (Core TH.FamilyResultSig)
2081 repNoSig = rep2 noSigName []
2082
2083 repKindSig :: Core TH.Kind -> DsM (Core TH.FamilyResultSig)
2084 repKindSig (MkC ki) = rep2 kindSigName [ki]
2085
2086 repTyVarSig :: Core TH.TyVarBndr -> DsM (Core TH.FamilyResultSig)
2087 repTyVarSig (MkC bndr) = rep2 tyVarSigName [bndr]
2088
2089 ----------------------------------------------------------
2090 -- Literals
2091
2092 repLiteral :: HsLit -> DsM (Core TH.Lit)
2093 repLiteral (HsStringPrim _ bs)
2094 = do dflags <- getDynFlags
2095 word8_ty <- lookupType word8TyConName
2096 let w8s = unpack bs
2097 w8s_expr = map (\w8 -> mkCoreConApps word8DataCon
2098 [mkWordLit dflags (toInteger w8)]) w8s
2099 rep2 stringPrimLName [mkListExpr word8_ty w8s_expr]
2100 repLiteral lit
2101 = do lit' <- case lit of
2102 HsIntPrim _ i -> mk_integer i
2103 HsWordPrim _ w -> mk_integer w
2104 HsInt _ i -> mk_integer i
2105 HsFloatPrim r -> mk_rational r
2106 HsDoublePrim r -> mk_rational r
2107 HsCharPrim _ c -> mk_char c
2108 _ -> return lit
2109 lit_expr <- dsLit lit'
2110 case mb_lit_name of
2111 Just lit_name -> rep2 lit_name [lit_expr]
2112 Nothing -> notHandled "Exotic literal" (ppr lit)
2113 where
2114 mb_lit_name = case lit of
2115 HsInteger _ _ _ -> Just integerLName
2116 HsInt _ _ -> Just integerLName
2117 HsIntPrim _ _ -> Just intPrimLName
2118 HsWordPrim _ _ -> Just wordPrimLName
2119 HsFloatPrim _ -> Just floatPrimLName
2120 HsDoublePrim _ -> Just doublePrimLName
2121 HsChar _ _ -> Just charLName
2122 HsCharPrim _ _ -> Just charPrimLName
2123 HsString _ _ -> Just stringLName
2124 HsRat _ _ -> Just rationalLName
2125 _ -> Nothing
2126
2127 mk_integer :: Integer -> DsM HsLit
2128 mk_integer i = do integer_ty <- lookupType integerTyConName
2129 return $ HsInteger "" i integer_ty
2130 mk_rational :: FractionalLit -> DsM HsLit
2131 mk_rational r = do rat_ty <- lookupType rationalTyConName
2132 return $ HsRat r rat_ty
2133 mk_string :: FastString -> DsM HsLit
2134 mk_string s = return $ HsString "" s
2135
2136 mk_char :: Char -> DsM HsLit
2137 mk_char c = return $ HsChar "" c
2138
2139 repOverloadedLiteral :: HsOverLit Name -> DsM (Core TH.Lit)
2140 repOverloadedLiteral (OverLit { ol_val = val})
2141 = do { lit <- mk_lit val; repLiteral lit }
2142 -- The type Rational will be in the environment, because
2143 -- the smart constructor 'TH.Syntax.rationalL' uses it in its type,
2144 -- and rationalL is sucked in when any TH stuff is used
2145
2146 mk_lit :: OverLitVal -> DsM HsLit
2147 mk_lit (HsIntegral _ i) = mk_integer i
2148 mk_lit (HsFractional f) = mk_rational f
2149 mk_lit (HsIsString _ s) = mk_string s
2150
2151 repNameS :: Core String -> DsM (Core TH.Name)
2152 repNameS (MkC name) = rep2 mkNameSName [name]
2153
2154 --------------- Miscellaneous -------------------
2155
2156 repGensym :: Core String -> DsM (Core (TH.Q TH.Name))
2157 repGensym (MkC lit_str) = rep2 newNameName [lit_str]
2158
2159 repBindQ :: Type -> Type -- a and b
2160 -> Core (TH.Q a) -> Core (a -> TH.Q b) -> DsM (Core (TH.Q b))
2161 repBindQ ty_a ty_b (MkC x) (MkC y)
2162 = rep2 bindQName [Type ty_a, Type ty_b, x, y]
2163
2164 repSequenceQ :: Type -> Core [TH.Q a] -> DsM (Core (TH.Q [a]))
2165 repSequenceQ ty_a (MkC list)
2166 = rep2 sequenceQName [Type ty_a, list]
2167
2168 repUnboundVar :: Core TH.Name -> DsM (Core TH.ExpQ)
2169 repUnboundVar (MkC name) = rep2 unboundVarEName [name]
2170
2171 ------------ Lists -------------------
2172 -- turn a list of patterns into a single pattern matching a list
2173
2174 repList :: Name -> (a -> DsM (Core b))
2175 -> [a] -> DsM (Core [b])
2176 repList tc_name f args
2177 = do { args1 <- mapM f args
2178 ; coreList tc_name args1 }
2179
2180 coreList :: Name -- Of the TyCon of the element type
2181 -> [Core a] -> DsM (Core [a])
2182 coreList tc_name es
2183 = do { elt_ty <- lookupType tc_name; return (coreList' elt_ty es) }
2184
2185 coreList' :: Type -- The element type
2186 -> [Core a] -> Core [a]
2187 coreList' elt_ty es = MkC (mkListExpr elt_ty (map unC es ))
2188
2189 nonEmptyCoreList :: [Core a] -> Core [a]
2190 -- The list must be non-empty so we can get the element type
2191 -- Otherwise use coreList
2192 nonEmptyCoreList [] = panic "coreList: empty argument"
2193 nonEmptyCoreList xs@(MkC x:_) = MkC (mkListExpr (exprType x) (map unC xs))
2194
2195 coreStringLit :: String -> DsM (Core String)
2196 coreStringLit s = do { z <- mkStringExpr s; return(MkC z) }
2197
2198 ------------------- Maybe ------------------
2199
2200 -- | Construct Core expression for Nothing of a given type name
2201 coreNothing :: Name -- ^ Name of the TyCon of the element type
2202 -> DsM (Core (Maybe a))
2203 coreNothing tc_name =
2204 do { elt_ty <- lookupType tc_name; return (coreNothing' elt_ty) }
2205
2206 -- | Construct Core expression for Nothing of a given type
2207 coreNothing' :: Type -- ^ The element type
2208 -> Core (Maybe a)
2209 coreNothing' elt_ty = MkC (mkNothingExpr elt_ty)
2210
2211 -- | Store given Core expression in a Just of a given type name
2212 coreJust :: Name -- ^ Name of the TyCon of the element type
2213 -> Core a -> DsM (Core (Maybe a))
2214 coreJust tc_name es
2215 = do { elt_ty <- lookupType tc_name; return (coreJust' elt_ty es) }
2216
2217 -- | Store given Core expression in a Just of a given type
2218 coreJust' :: Type -- ^ The element type
2219 -> Core a -> Core (Maybe a)
2220 coreJust' elt_ty es = MkC (mkJustExpr elt_ty (unC es))
2221
2222 ------------ Literals & Variables -------------------
2223
2224 coreIntLit :: Int -> DsM (Core Int)
2225 coreIntLit i = do dflags <- getDynFlags
2226 return (MkC (mkIntExprInt dflags i))
2227
2228 coreVar :: Id -> Core TH.Name -- The Id has type Name
2229 coreVar id = MkC (Var id)
2230
2231 ----------------- Failure -----------------------
2232 notHandledL :: SrcSpan -> String -> SDoc -> DsM a
2233 notHandledL loc what doc
2234 | isGoodSrcSpan loc
2235 = putSrcSpanDs loc $ notHandled what doc
2236 | otherwise
2237 = notHandled what doc
2238
2239 notHandled :: String -> SDoc -> DsM a
2240 notHandled what doc = failWithDs msg
2241 where
2242 msg = hang (text what <+> ptext (sLit "not (yet) handled by Template Haskell"))
2243 2 doc