1 -----------------------------------------------------------------------------
2 -- The purpose of this module is to transform an HsExpr into a CoreExpr which
3 -- when evaluated, returns a (Meta.Q Meta.Exp) computation analogous to the
4 -- input HsExpr. We do this in the DsM monad, which supplies access to
5 -- CoreExpr's of the "smart constructors" of the Meta.Exp datatype.
7 -- It also defines a bunch of knownKeyNames, in the same way as is done
8 -- in prelude/PrelNames. It's much more convenient to do it here, becuase
9 -- otherwise we have to recompile PrelNames whenever we add a Name, which is
10 -- a Royal Pain (triggers other recompilation).
11 -----------------------------------------------------------------------------
14 module DsMeta( dsBracket, dsReify,
15 templateHaskellNames, qTyConName,
16 liftName, expQTyConName, decQTyConName, typeQTyConName,
17 decTyConName, typeTyConName ) where
19 #include "HsVersions.h"
21 import {-# SOURCE #-} DsExpr ( dsExpr )
23 import MatchLit ( dsLit )
24 import DsUtils ( mkListExpr, mkStringLit, mkCoreTup, mkIntExpr )
27 import qualified Language.Haskell.THSyntax as M
29 import HsSyn ( Pat(..), HsExpr(..), Stmt(..), HsLit(..), HsOverLit(..),
30 Match(..), GRHSs(..), GRHS(..), HsBracket(..),
31 HsStmtContext(ListComp,DoExpr), ArithSeqInfo(..),
32 HsBinds(..), MonoBinds(..), HsConDetails(..),
33 TyClDecl(..), HsGroup(..),
34 HsReify(..), ReifyFlavour(..),
35 HsType(..), HsContext(..), HsPred(..), HsTyOp(..),
36 HsTyVarBndr(..), Sig(..), ForeignDecl(..),
37 InstDecl(..), ConDecl(..), BangType(..),
38 PendingSplice, splitHsInstDeclTy,
39 placeHolderType, tyClDeclNames,
40 collectHsBinders, collectPatBinders, collectPatsBinders,
41 hsTyVarName, hsConArgs, getBangType,
45 import PrelNames ( mETA_META_Name, rationalTyConName, negateName,
47 import MkIface ( ifaceTyThing )
48 import Name ( Name, nameOccName, nameModule, getSrcLoc )
49 import OccName ( isDataOcc, isTvOcc, occNameUserString )
50 -- To avoid clashes with DsMeta.varName we must make a local alias for OccName.varName
51 -- we do this by removing varName from the import of OccName above, making
52 -- a qualified instance of OccName and using OccNameAlias.varName where varName
53 -- ws previously used in this file.
54 import qualified OccName( varName, tcName )
56 import Module ( Module, mkThPkgModule, moduleUserString )
57 import Id ( Id, idType )
58 import Name ( mkKnownKeyExternalName )
59 import OccName ( mkOccFS )
62 import Type ( Type, mkGenTyConApp )
63 import TcType ( TyThing(..), tcTyConAppArgs )
64 import TyCon ( DataConDetails(..) )
65 import TysWiredIn ( stringTy )
67 import CoreUtils ( exprType )
68 import SrcLoc ( noSrcLoc )
69 import Maybes ( orElse )
70 import Maybe ( catMaybes, fromMaybe )
71 import Panic ( panic )
72 import Unique ( mkPreludeTyConUnique, mkPreludeMiscIdUnique )
73 import BasicTypes ( NewOrData(..), StrictnessMark(..), isBoxed )
74 import SrcLoc ( SrcLoc )
77 import FastString ( mkFastString )
79 import Monad ( zipWithM )
80 import List ( sortBy )
82 -----------------------------------------------------------------------------
83 dsBracket :: HsBracket Name -> [PendingSplice] -> DsM CoreExpr
84 -- Returns a CoreExpr of type M.ExpQ
85 -- The quoted thing is parameterised over Name, even though it has
86 -- been type checked. We don't want all those type decorations!
88 dsBracket brack splices
89 = dsExtendMetaEnv new_bit (do_brack brack)
91 new_bit = mkNameEnv [(n, Splice e) | (n,e) <- splices]
93 do_brack (ExpBr e) = do { MkC e1 <- repE e ; return e1 }
94 do_brack (PatBr p) = do { MkC p1 <- repP p ; return p1 }
95 do_brack (TypBr t) = do { MkC t1 <- repTy t ; return t1 }
96 do_brack (DecBr ds) = do { MkC ds1 <- repTopDs ds ; return ds1 }
98 -----------------------------------------------------------------------------
99 dsReify :: HsReify Id -> DsM CoreExpr
100 -- Returns a CoreExpr of type reifyType --> M.TypeQ
101 -- reifyDecl --> M.DecQ
102 -- reifyFixty --> Q M.Fix
103 dsReify (ReifyOut ReifyType name)
104 = do { thing <- dsLookupGlobal name ;
105 -- By deferring the lookup until now (rather than doing it
106 -- in the type checker) we ensure that all zonking has
109 AnId id -> do { MkC e <- repTy (toHsType (idType id)) ;
111 other -> pprPanic "dsReify: reifyType" (ppr name)
114 dsReify r@(ReifyOut ReifyDecl name)
115 = do { thing <- dsLookupGlobal name ;
116 mb_d <- repTyClD (ifaceTyThing thing) ;
118 Just (MkC d) -> return d
119 Nothing -> pprPanic "dsReify" (ppr r)
122 {- -------------- Examples --------------------
126 gensym (unpackString "x"#) `bindQ` \ x1::String ->
127 lam (pvar x1) (var x1)
130 [| \x -> $(f [| x |]) |]
132 gensym (unpackString "x"#) `bindQ` \ x1::String ->
133 lam (pvar x1) (f (var x1))
137 -------------------------------------------------------
139 -------------------------------------------------------
141 repTopDs :: HsGroup Name -> DsM (Core (M.Q [M.Dec]))
143 = do { let { bndrs = groupBinders group } ;
144 ss <- mkGenSyms bndrs ;
146 -- Bind all the names mainly to avoid repeated use of explicit strings.
148 -- do { t :: String <- genSym "T" ;
149 -- return (Data t [] ...more t's... }
150 -- The other important reason is that the output must mention
151 -- only "T", not "Foo:T" where Foo is the current module
154 decls <- addBinds ss (do {
155 val_ds <- rep_binds' (hs_valds group) ;
156 tycl_ds <- mapM repTyClD' (hs_tyclds group) ;
157 inst_ds <- mapM repInstD' (hs_instds group) ;
159 return (de_loc $ sort_by_loc $ val_ds ++ catMaybes tycl_ds ++ inst_ds) }) ;
161 decl_ty <- lookupType decQTyConName ;
162 let { core_list = coreList' decl_ty decls } ;
164 dec_ty <- lookupType decTyConName ;
165 q_decs <- repSequenceQ dec_ty core_list ;
167 wrapNongenSyms ss q_decs
168 -- Do *not* gensym top-level binders
171 groupBinders (HsGroup { hs_valds = val_decls, hs_tyclds = tycl_decls,
172 hs_fords = foreign_decls })
173 -- Collect the binders of a Group
174 = collectHsBinders val_decls ++
175 [n | d <- tycl_decls, (n,_) <- tyClDeclNames d] ++
176 [n | ForeignImport n _ _ _ _ <- foreign_decls]
179 {- Note [Binders and occurrences]
180 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
181 When we desugar [d| data T = MkT |]
183 Data "T" [] [Con "MkT" []] []
185 Data "Foo:T" [] [Con "Foo:MkT" []] []
186 That is, the new data decl should fit into whatever new module it is
187 asked to fit in. We do *not* clone, though; no need for this:
194 then we must desugar to
195 foo = Data "Foo:T" [] [Con "Foo:MkT" []] []
197 So in repTopDs we bring the binders into scope with mkGenSyms and addBinds,
198 but in dsReify we do not. And we use lookupOcc, rather than lookupBinder
199 in repTyClD and repC.
203 repTyClD :: TyClDecl Name -> DsM (Maybe (Core M.DecQ))
204 repTyClD decl = do x <- repTyClD' decl
207 repTyClD' :: TyClDecl Name -> DsM (Maybe (SrcLoc, Core M.DecQ))
209 repTyClD' (TyData { tcdND = DataType, tcdCtxt = cxt,
210 tcdName = tc, tcdTyVars = tvs,
211 tcdCons = DataCons cons, tcdDerivs = mb_derivs,
213 = do { tc1 <- lookupOcc tc ; -- See note [Binders and occurrences]
214 dec <- addTyVarBinds tvs $ \bndrs -> do {
215 cxt1 <- repContext cxt ;
216 cons1 <- mapM repC cons ;
217 cons2 <- coreList conQTyConName cons1 ;
218 derivs1 <- repDerivs mb_derivs ;
219 repData cxt1 tc1 (coreList' stringTy bndrs) cons2 derivs1 } ;
220 return $ Just (loc, dec) }
222 repTyClD' (TyData { tcdND = NewType, tcdCtxt = cxt,
223 tcdName = tc, tcdTyVars = tvs,
224 tcdCons = DataCons [con], tcdDerivs = mb_derivs,
226 = do { tc1 <- lookupOcc tc ; -- See note [Binders and occurrences]
227 dec <- addTyVarBinds tvs $ \bndrs -> do {
228 cxt1 <- repContext cxt ;
230 derivs1 <- repDerivs mb_derivs ;
231 repNewtype cxt1 tc1 (coreList' stringTy bndrs) con1 derivs1 } ;
232 return $ Just (loc, dec) }
234 repTyClD' (TySynonym { tcdName = tc, tcdTyVars = tvs, tcdSynRhs = ty,
236 = do { tc1 <- lookupOcc tc ; -- See note [Binders and occurrences]
237 dec <- addTyVarBinds tvs $ \bndrs -> do {
239 repTySyn tc1 (coreList' stringTy bndrs) ty1 } ;
240 return (Just (loc, dec)) }
242 repTyClD' (ClassDecl { tcdCtxt = cxt, tcdName = cls,
244 tcdFDs = [], -- We don't understand functional dependencies
245 tcdSigs = sigs, tcdMeths = mb_meth_binds,
247 = do { cls1 <- lookupOcc cls ; -- See note [Binders and occurrences]
248 dec <- addTyVarBinds tvs $ \bndrs -> do {
249 cxt1 <- repContext cxt ;
250 sigs1 <- rep_sigs sigs ;
251 binds1 <- rep_monobind meth_binds ;
252 decls1 <- coreList decQTyConName (sigs1 ++ binds1) ;
253 repClass cxt1 cls1 (coreList' stringTy bndrs) decls1 } ;
254 return $ Just (loc, dec) }
256 -- If the user quotes a class decl, it'll have default-method
257 -- bindings; but if we (reifyDecl C) where C is a class, we
258 -- won't be given the default methods (a definite infelicity).
259 meth_binds = mb_meth_binds `orElse` EmptyMonoBinds
262 repTyClD' d = do { addDsWarn (hang msg 4 (ppr d)) ;
266 msg = ptext SLIT("Cannot desugar this Template Haskell declaration:")
268 repInstD' (InstDecl ty binds _ _ loc)
269 -- Ignore user pragmas for now
270 = do { cxt1 <- repContext cxt ;
271 inst_ty1 <- repPred (HsClassP cls tys) ;
272 binds1 <- rep_monobind binds ;
273 decls1 <- coreList decQTyConName binds1 ;
274 i <- repInst cxt1 inst_ty1 decls1;
277 (tvs, cxt, cls, tys) = splitHsInstDeclTy ty
280 -------------------------------------------------------
282 -------------------------------------------------------
284 repC :: ConDecl Name -> DsM (Core M.ConQ)
285 repC (ConDecl con [] [] details loc)
286 = do { con1 <- lookupOcc con ; -- See note [Binders and occurrences]
287 repConstr con1 details }
289 repBangTy :: BangType Name -> DsM (Core (M.StrictTypeQ))
290 repBangTy (BangType str ty) = do MkC s <- rep2 strName []
292 rep2 strictTypeName [s, t]
293 where strName = case str of
294 NotMarkedStrict -> notStrictName
297 -------------------------------------------------------
299 -------------------------------------------------------
301 repDerivs :: Maybe (HsContext Name) -> DsM (Core [String])
302 repDerivs Nothing = return (coreList' stringTy [])
303 repDerivs (Just ctxt)
304 = do { strs <- mapM rep_deriv ctxt ;
305 return (coreList' stringTy strs) }
307 rep_deriv :: HsPred Name -> DsM (Core String)
308 -- Deriving clauses must have the simple H98 form
309 rep_deriv (HsClassP cls []) = lookupOcc cls
310 rep_deriv other = panic "rep_deriv"
313 -------------------------------------------------------
314 -- Signatures in a class decl, or a group of bindings
315 -------------------------------------------------------
317 rep_sigs :: [Sig Name] -> DsM [Core M.DecQ]
318 rep_sigs sigs = do locs_cores <- rep_sigs' sigs
319 return $ de_loc $ sort_by_loc locs_cores
321 rep_sigs' :: [Sig Name] -> DsM [(SrcLoc, Core M.DecQ)]
322 -- We silently ignore ones we don't recognise
323 rep_sigs' sigs = do { sigs1 <- mapM rep_sig sigs ;
324 return (concat sigs1) }
326 rep_sig :: Sig Name -> DsM [(SrcLoc, Core M.DecQ)]
328 -- Empty => Too hard, signature ignored
329 rep_sig (ClassOpSig nm _ ty loc) = rep_proto nm ty loc
330 rep_sig (Sig nm ty loc) = rep_proto nm ty loc
331 rep_sig other = return []
333 rep_proto :: Name -> HsType Name -> SrcLoc -> DsM [(SrcLoc, Core M.DecQ)]
334 rep_proto nm ty loc = do { nm1 <- lookupOcc nm ;
336 sig <- repProto nm1 ty1 ;
337 return [(loc, sig)] }
340 -------------------------------------------------------
342 -------------------------------------------------------
344 -- gensym a list of type variables and enter them into the meta environment;
345 -- the computations passed as the second argument is executed in that extended
346 -- meta environment and gets the *new* names on Core-level as an argument
348 addTyVarBinds :: [HsTyVarBndr Name] -- the binders to be added
349 -> ([Core String] -> DsM (Core (M.Q a))) -- action in the ext env
350 -> DsM (Core (M.Q a))
351 addTyVarBinds tvs m =
353 let names = map hsTyVarName tvs
354 freshNames <- mkGenSyms names
355 term <- addBinds freshNames $ do
356 bndrs <- mapM lookupBinder names
358 wrapGenSyns freshNames term
360 -- represent a type context
362 repContext :: HsContext Name -> DsM (Core M.CxtQ)
364 preds <- mapM repPred ctxt
365 predList <- coreList typeQTyConName preds
368 -- represent a type predicate
370 repPred :: HsPred Name -> DsM (Core M.TypeQ)
371 repPred (HsClassP cls tys) = do
372 tcon <- repTy (HsTyVar cls)
375 repPred (HsIParam _ _) =
376 panic "DsMeta.repTy: Can't represent predicates with implicit parameters"
378 -- yield the representation of a list of types
380 repTys :: [HsType Name] -> DsM [Core M.TypeQ]
381 repTys tys = mapM repTy tys
385 repTy :: HsType Name -> DsM (Core M.TypeQ)
386 repTy (HsForAllTy bndrs ctxt ty) =
387 addTyVarBinds (fromMaybe [] bndrs) $ \bndrs' -> do
388 ctxt' <- repContext ctxt
390 repTForall (coreList' stringTy bndrs') ctxt' ty'
393 | isTvOcc (nameOccName n) = do
394 tv1 <- lookupBinder n
399 repTy (HsAppTy f a) = do
403 repTy (HsFunTy f a) = do
406 tcon <- repArrowTyCon
407 repTapps tcon [f1, a1]
408 repTy (HsListTy t) = do
412 repTy (HsPArrTy t) = do
414 tcon <- repTy (HsTyVar parrTyConName)
416 repTy (HsTupleTy tc tys) = do
418 tcon <- repTupleTyCon (length tys)
420 repTy (HsOpTy ty1 HsArrow ty2) = repTy (HsFunTy ty1 ty2)
421 repTy (HsOpTy ty1 (HsTyOp n) ty2) = repTy ((HsTyVar n `HsAppTy` ty1)
423 repTy (HsParTy t) = repTy t
425 panic "DsMeta.repTy: Can't represent number types (for generics)"
426 repTy (HsPredTy pred) = repPred pred
427 repTy (HsKindSig ty kind) =
428 panic "DsMeta.repTy: Can't represent explicit kind signatures yet"
431 -----------------------------------------------------------------------------
433 -----------------------------------------------------------------------------
435 repEs :: [HsExpr Name] -> DsM (Core [M.ExpQ])
436 repEs es = do { es' <- mapM repE es ;
437 coreList expQTyConName es' }
439 -- FIXME: some of these panics should be converted into proper error messages
440 -- unless we can make sure that constructs, which are plainly not
441 -- supported in TH already lead to error messages at an earlier stage
442 repE :: HsExpr Name -> DsM (Core M.ExpQ)
444 do { mb_val <- dsLookupMetaEnv x
446 Nothing -> do { str <- globalVar x
447 ; repVarOrCon x str }
448 Just (Bound y) -> repVarOrCon x (coreVar y)
449 Just (Splice e) -> do { e' <- dsExpr e
450 ; return (MkC e') } }
451 repE (HsIPVar x) = panic "DsMeta.repE: Can't represent implicit parameters"
453 -- Remember, we're desugaring renamer output here, so
454 -- HsOverlit can definitely occur
455 repE (HsOverLit l) = do { a <- repOverloadedLiteral l; repLit a }
456 repE (HsLit l) = do { a <- repLiteral l; repLit a }
457 repE (HsLam m) = repLambda m
458 repE (HsApp x y) = do {a <- repE x; b <- repE y; repApp a b}
460 repE (OpApp e1 op fix e2) =
461 do { arg1 <- repE e1;
464 repInfixApp arg1 the_op arg2 }
465 repE (NegApp x nm) = do
467 negateVar <- lookupOcc negateName >>= repVar
469 repE (HsPar x) = repE x
470 repE (SectionL x y) = do { a <- repE x; b <- repE y; repSectionL a b }
471 repE (SectionR x y) = do { a <- repE x; b <- repE y; repSectionR a b }
472 repE (HsCase e ms loc) = do { arg <- repE e
473 ; ms2 <- mapM repMatchTup ms
474 ; repCaseE arg (nonEmptyCoreList ms2) }
475 repE (HsIf x y z loc) = do
480 repE (HsLet bs e) = do { (ss,ds) <- repBinds bs
481 ; e2 <- addBinds ss (repE e)
484 -- FIXME: I haven't got the types here right yet
485 repE (HsDo DoExpr sts _ ty loc)
486 = do { (ss,zs) <- repSts sts;
487 e <- repDoE (nonEmptyCoreList zs);
489 repE (HsDo ListComp sts _ ty loc)
490 = do { (ss,zs) <- repSts sts;
491 e <- repComp (nonEmptyCoreList zs);
493 repE (HsDo _ _ _ _ _) = panic "DsMeta.repE: Can't represent mdo and [: :] yet"
494 repE (ExplicitList ty es) = do { xs <- repEs es; repListExp xs }
495 repE (ExplicitPArr ty es) =
496 panic "DsMeta.repE: No explicit parallel arrays yet"
497 repE (ExplicitTuple es boxed)
498 | isBoxed boxed = do { xs <- repEs es; repTup xs }
499 | otherwise = panic "DsMeta.repE: Can't represent unboxed tuples"
500 repE (RecordCon c flds)
501 = do { x <- lookupOcc c;
502 fs <- repFields flds;
504 repE (RecordUpd e flds)
506 fs <- repFields flds;
509 repE (ExprWithTySig e ty) = do { e1 <- repE e; t1 <- repTy ty; repSigExp e1 t1 }
510 repE (ArithSeqIn aseq) =
512 From e -> do { ds1 <- repE e; repFrom ds1 }
521 FromThenTo e1 e2 e3 -> do
525 repFromThenTo ds1 ds2 ds3
526 repE (PArrSeqOut _ aseq) = panic "DsMeta.repE: parallel array seq.s missing"
527 repE (HsCoreAnn _ _) = panic "DsMeta.repE: Can't represent CoreAnn" -- hdaume: core annotations
528 repE (HsCCall _ _ _ _ _) = panic "DsMeta.repE: Can't represent __ccall__"
529 repE (HsSCC _ _) = panic "DsMeta.repE: Can't represent SCC"
530 repE (HsBracketOut _ _) =
531 panic "DsMeta.repE: Can't represent Oxford brackets"
532 repE (HsSplice n e loc) = do { mb_val <- dsLookupMetaEnv n
534 Just (Splice e) -> do { e' <- dsExpr e
536 other -> pprPanic "HsSplice" (ppr n) }
537 repE (HsReify _) = panic "DsMeta.repE: Can't represent reification"
539 pprPanic "DsMeta.repE: Illegal expression form" (ppr e)
541 -----------------------------------------------------------------------------
542 -- Building representations of auxillary structures like Match, Clause, Stmt,
544 repMatchTup :: Match Name -> DsM (Core M.MatchQ)
545 repMatchTup (Match [p] ty (GRHSs guards wheres ty2)) =
546 do { ss1 <- mkGenSyms (collectPatBinders p)
547 ; addBinds ss1 $ do {
549 ; (ss2,ds) <- repBinds wheres
550 ; addBinds ss2 $ do {
551 ; gs <- repGuards guards
552 ; match <- repMatch p1 gs ds
553 ; wrapGenSyns (ss1++ss2) match }}}
555 repClauseTup :: Match Name -> DsM (Core M.ClauseQ)
556 repClauseTup (Match ps ty (GRHSs guards wheres ty2)) =
557 do { ss1 <- mkGenSyms (collectPatsBinders ps)
558 ; addBinds ss1 $ do {
560 ; (ss2,ds) <- repBinds wheres
561 ; addBinds ss2 $ do {
562 gs <- repGuards guards
563 ; clause <- repClause ps1 gs ds
564 ; wrapGenSyns (ss1++ss2) clause }}}
566 repGuards :: [GRHS Name] -> DsM (Core M.BodyQ)
567 repGuards [GRHS [ResultStmt e loc] loc2]
568 = do {a <- repE e; repNormal a }
570 = do { zs <- mapM process other;
571 repGuarded (nonEmptyCoreList (map corePair zs)) }
573 process (GRHS [ExprStmt e1 ty loc,ResultStmt e2 _] _)
574 = do { x <- repE e1; y <- repE e2; return (x, y) }
575 process other = panic "Non Haskell 98 guarded body"
577 repFields :: [(Name,HsExpr Name)] -> DsM (Core [M.FieldExp])
579 fnames <- mapM lookupOcc (map fst flds)
580 es <- mapM repE (map snd flds)
581 fs <- zipWithM (\n x -> rep2 fieldExpName [unC n, unC x]) fnames es
582 coreList fieldExpTyConName fs
585 -----------------------------------------------------------------------------
586 -- Representing Stmt's is tricky, especially if bound variables
587 -- shaddow each other. Consider: [| do { x <- f 1; x <- f x; g x } |]
588 -- First gensym new names for every variable in any of the patterns.
589 -- both static (x'1 and x'2), and dynamic ((gensym "x") and (gensym "y"))
590 -- if variables didn't shaddow, the static gensym wouldn't be necessary
591 -- and we could reuse the original names (x and x).
593 -- do { x'1 <- gensym "x"
594 -- ; x'2 <- gensym "x"
595 -- ; doE [ BindSt (pvar x'1) [| f 1 |]
596 -- , BindSt (pvar x'2) [| f x |]
597 -- , NoBindSt [| g x |]
601 -- The strategy is to translate a whole list of do-bindings by building a
602 -- bigger environment, and a bigger set of meta bindings
603 -- (like: x'1 <- gensym "x" ) and then combining these with the translations
604 -- of the expressions within the Do
606 -----------------------------------------------------------------------------
607 -- The helper function repSts computes the translation of each sub expression
608 -- and a bunch of prefix bindings denoting the dynamic renaming.
610 repSts :: [Stmt Name] -> DsM ([GenSymBind], [Core M.StmtQ])
611 repSts [ResultStmt e loc] =
613 ; e1 <- repNoBindSt a
614 ; return ([], [e1]) }
615 repSts (BindStmt p e loc : ss) =
617 ; ss1 <- mkGenSyms (collectPatBinders p)
618 ; addBinds ss1 $ do {
620 ; (ss2,zs) <- repSts ss
621 ; z <- repBindSt p1 e2
622 ; return (ss1++ss2, z : zs) }}
623 repSts (LetStmt bs : ss) =
624 do { (ss1,ds) <- repBinds bs
626 ; (ss2,zs) <- addBinds ss1 (repSts ss)
627 ; return (ss1++ss2, z : zs) }
628 repSts (ExprStmt e ty loc : ss) =
630 ; z <- repNoBindSt e2
631 ; (ss2,zs) <- repSts ss
632 ; return (ss2, z : zs) }
633 repSts other = panic "Exotic Stmt in meta brackets"
636 -----------------------------------------------------------
638 -----------------------------------------------------------
640 repBinds :: HsBinds Name -> DsM ([GenSymBind], Core [M.DecQ])
642 = do { let { bndrs = collectHsBinders decs } ;
643 ss <- mkGenSyms bndrs ;
644 core <- addBinds ss (rep_binds decs) ;
645 core_list <- coreList decQTyConName core ;
646 return (ss, core_list) }
648 rep_binds :: HsBinds Name -> DsM [Core M.DecQ]
649 rep_binds binds = do locs_cores <- rep_binds' binds
650 return $ de_loc $ sort_by_loc locs_cores
652 rep_binds' :: HsBinds Name -> DsM [(SrcLoc, Core M.DecQ)]
653 rep_binds' EmptyBinds = return []
654 rep_binds' (ThenBinds x y)
655 = do { core1 <- rep_binds' x
656 ; core2 <- rep_binds' y
657 ; return (core1 ++ core2) }
658 rep_binds' (MonoBind bs sigs _)
659 = do { core1 <- rep_monobind' bs
660 ; core2 <- rep_sigs' sigs
661 ; return (core1 ++ core2) }
662 rep_binds' (IPBinds _ _)
663 = panic "DsMeta:repBinds: can't do implicit parameters"
665 rep_monobind :: MonoBinds Name -> DsM [Core M.DecQ]
666 rep_monobind binds = do locs_cores <- rep_monobind' binds
667 return $ de_loc $ sort_by_loc locs_cores
669 rep_monobind' :: MonoBinds Name -> DsM [(SrcLoc, Core M.DecQ)]
670 rep_monobind' EmptyMonoBinds = return []
671 rep_monobind' (AndMonoBinds x y) = do { x1 <- rep_monobind' x;
672 y1 <- rep_monobind' y;
675 -- Note GHC treats declarations of a variable (not a pattern)
676 -- e.g. x = g 5 as a Fun MonoBinds. This is indicated by a single match
677 -- with an empty list of patterns
678 rep_monobind' (FunMonoBind fn infx [Match [] ty (GRHSs guards wheres ty2)] loc)
679 = do { (ss,wherecore) <- repBinds wheres
680 ; guardcore <- addBinds ss (repGuards guards)
681 ; fn' <- lookupBinder fn
683 ; ans <- repVal p guardcore wherecore
684 ; return [(loc, ans)] }
686 rep_monobind' (FunMonoBind fn infx ms loc)
687 = do { ms1 <- mapM repClauseTup ms
688 ; fn' <- lookupBinder fn
689 ; ans <- repFun fn' (nonEmptyCoreList ms1)
690 ; return [(loc, ans)] }
692 rep_monobind' (PatMonoBind pat (GRHSs guards wheres ty2) loc)
693 = do { patcore <- repP pat
694 ; (ss,wherecore) <- repBinds wheres
695 ; guardcore <- addBinds ss (repGuards guards)
696 ; ans <- repVal patcore guardcore wherecore
697 ; return [(loc, ans)] }
699 rep_monobind' (VarMonoBind v e)
700 = do { v' <- lookupBinder v
703 ; patcore <- repPvar v'
704 ; empty_decls <- coreList decQTyConName []
705 ; ans <- repVal patcore x empty_decls
706 ; return [(getSrcLoc v, ans)] }
708 -----------------------------------------------------------------------------
709 -- Since everything in a MonoBind is mutually recursive we need rename all
710 -- all the variables simultaneously. For example:
711 -- [| AndMonoBinds (f x = x + g 2) (g x = f 1 + 2) |] would translate to
712 -- do { f'1 <- gensym "f"
713 -- ; g'2 <- gensym "g"
714 -- ; [ do { x'3 <- gensym "x"; fun f'1 [pvar x'3] [| x + g2 |]},
715 -- do { x'4 <- gensym "x"; fun g'2 [pvar x'4] [| f 1 + 2 |]}
717 -- This requires collecting the bindings (f'1 <- gensym "f"), and the
718 -- environment ( f |-> f'1 ) from each binding, and then unioning them
719 -- together. As we do this we collect GenSymBinds's which represent the renamed
720 -- variables bound by the Bindings. In order not to lose track of these
721 -- representations we build a shadow datatype MB with the same structure as
722 -- MonoBinds, but which has slots for the representations
725 -----------------------------------------------------------------------------
726 -- GHC allows a more general form of lambda abstraction than specified
727 -- by Haskell 98. In particular it allows guarded lambda's like :
728 -- (\ x | even x -> 0 | odd x -> 1) at the moment we can't represent this in
729 -- Haskell Template's Meta.Exp type so we punt if it isn't a simple thing like
730 -- (\ p1 .. pn -> exp) by causing an error.
732 repLambda :: Match Name -> DsM (Core M.ExpQ)
733 repLambda (Match ps _ (GRHSs [GRHS [ResultStmt e _ ] _ ]
735 = do { let bndrs = collectPatsBinders ps ;
736 ; ss <- mkGenSyms bndrs
737 ; lam <- addBinds ss (
738 do { xs <- repPs ps; body <- repE e; repLam xs body })
739 ; wrapGenSyns ss lam }
741 repLambda z = panic "Can't represent a guarded lambda in Template Haskell"
744 -----------------------------------------------------------------------------
746 -- repP deals with patterns. It assumes that we have already
747 -- walked over the pattern(s) once to collect the binders, and
748 -- have extended the environment. So every pattern-bound
749 -- variable should already appear in the environment.
751 -- Process a list of patterns
752 repPs :: [Pat Name] -> DsM (Core [M.Pat])
753 repPs ps = do { ps' <- mapM repP ps ;
754 coreList patTyConName ps' }
756 repP :: Pat Name -> DsM (Core M.Pat)
757 repP (WildPat _) = repPwild
758 repP (LitPat l) = do { l2 <- repLiteral l; repPlit l2 }
759 repP (VarPat x) = do { x' <- lookupBinder x; repPvar x' }
760 repP (LazyPat p) = do { p1 <- repP p; repPtilde p1 }
761 repP (AsPat x p) = do { x' <- lookupBinder x; p1 <- repP p; repPaspat x' p1 }
762 repP (ParPat p) = repP p
763 repP (ListPat ps _) = repListPat ps
764 repP (TuplePat ps _) = do { qs <- repPs ps; repPtup qs }
765 repP (ConPatIn dc details)
766 = do { con_str <- lookupOcc dc
768 PrefixCon ps -> do { qs <- repPs ps; repPcon con_str qs }
769 RecCon pairs -> do { vs <- sequence $ map lookupOcc (map fst pairs)
770 ; ps <- sequence $ map repP (map snd pairs)
771 ; fps <- zipWithM (\x y -> rep2 fieldPatName [unC x,unC y]) vs ps
772 ; fps' <- coreList fieldPatTyConName fps
773 ; repPrec con_str fps' }
774 InfixCon p1 p2 -> do { qs <- repPs [p1,p2]; repPcon con_str qs }
776 repP (NPatIn l (Just _)) = panic "Can't cope with negative overloaded patterns yet (repP (NPatIn _ (Just _)))"
777 repP (NPatIn l Nothing) = do { a <- repOverloadedLiteral l; repPlit a }
778 repP other = panic "Exotic pattern inside meta brackets"
780 repListPat :: [Pat Name] -> DsM (Core M.Pat)
781 repListPat [] = do { nil_con <- coreStringLit "[]"
782 ; nil_args <- coreList patTyConName []
783 ; repPcon nil_con nil_args }
784 repListPat (p:ps) = do { p2 <- repP p
785 ; ps2 <- repListPat ps
786 ; cons_con <- coreStringLit ":"
787 ; repPcon cons_con (nonEmptyCoreList [p2,ps2]) }
790 ----------------------------------------------------------
791 -- Declaration ordering helpers
793 sort_by_loc :: [(SrcLoc, a)] -> [(SrcLoc, a)]
794 sort_by_loc xs = sortBy comp xs
795 where comp x y = compare (fst x) (fst y)
797 de_loc :: [(SrcLoc, a)] -> [a]
800 ----------------------------------------------------------
801 -- The meta-environment
803 -- A name/identifier association for fresh names of locally bound entities
805 type GenSymBind = (Name, Id) -- Gensym the string and bind it to the Id
806 -- I.e. (x, x_id) means
807 -- let x_id = gensym "x" in ...
809 -- Generate a fresh name for a locally bound entity
811 mkGenSym :: Name -> DsM GenSymBind
812 mkGenSym nm = do { id <- newUniqueId nm stringTy; return (nm,id) }
814 -- Ditto for a list of names
816 mkGenSyms :: [Name] -> DsM [GenSymBind]
817 mkGenSyms ns = mapM mkGenSym ns
819 -- Add a list of fresh names for locally bound entities to the meta
820 -- environment (which is part of the state carried around by the desugarer
823 addBinds :: [GenSymBind] -> DsM a -> DsM a
824 addBinds bs m = dsExtendMetaEnv (mkNameEnv [(n,Bound id) | (n,id) <- bs]) m
826 -- Look up a locally bound name
828 lookupBinder :: Name -> DsM (Core String)
830 = do { mb_val <- dsLookupMetaEnv n;
832 Just (Bound x) -> return (coreVar x)
833 other -> pprPanic "Failed binder lookup:" (ppr n) }
835 -- Look up a name that is either locally bound or a global name
837 -- * If it is a global name, generate the "original name" representation (ie,
838 -- the <module>:<name> form) for the associated entity
840 lookupOcc :: Name -> DsM (Core String)
841 -- Lookup an occurrence; it can't be a splice.
842 -- Use the in-scope bindings if they exist
844 = do { mb_val <- dsLookupMetaEnv n ;
846 Nothing -> globalVar n
847 Just (Bound x) -> return (coreVar x)
848 Just (Splice _) -> pprPanic "repE:lookupOcc" (ppr n)
851 globalVar :: Name -> DsM (Core String)
852 globalVar n = coreStringLit (name_mod ++ ":" ++ name_occ)
854 name_mod = moduleUserString (nameModule n)
855 name_occ = occNameUserString (nameOccName n)
857 localVar :: Name -> DsM (Core String)
858 localVar n = coreStringLit (occNameUserString (nameOccName n))
860 lookupType :: Name -- Name of type constructor (e.g. M.ExpQ)
861 -> DsM Type -- The type
862 lookupType tc_name = do { tc <- dsLookupTyCon tc_name ;
863 return (mkGenTyConApp tc []) }
865 -- wrapGenSyns [(nm1,id1), (nm2,id2)] y
866 -- --> bindQ (gensym nm1) (\ id1 ->
867 -- bindQ (gensym nm2 (\ id2 ->
870 wrapGenSyns :: [GenSymBind]
871 -> Core (M.Q a) -> DsM (Core (M.Q a))
872 wrapGenSyns binds body@(MkC b)
875 [elt_ty] = tcTyConAppArgs (exprType b)
876 -- b :: Q a, so we can get the type 'a' by looking at the
877 -- argument type. NB: this relies on Q being a data/newtype,
878 -- not a type synonym
881 go ((name,id) : binds)
882 = do { MkC body' <- go binds
883 ; lit_str <- localVar name
884 ; gensym_app <- repGensym lit_str
885 ; repBindQ stringTy elt_ty
886 gensym_app (MkC (Lam id body')) }
888 -- Just like wrapGenSym, but don't actually do the gensym
889 -- Instead use the existing name
890 -- Only used for [Decl]
891 wrapNongenSyms :: [GenSymBind] -> Core a -> DsM (Core a)
892 wrapNongenSyms binds (MkC body)
893 = do { binds' <- mapM do_one binds ;
894 return (MkC (mkLets binds' body)) }
897 = do { MkC lit_str <- localVar name -- No gensym
898 ; return (NonRec id lit_str) }
900 void = placeHolderType
902 string :: String -> HsExpr Id
903 string s = HsLit (HsString (mkFastString s))
906 -- %*********************************************************************
910 -- %*********************************************************************
912 -----------------------------------------------------------------------------
913 -- PHANTOM TYPES for consistency. In order to make sure we do this correct
914 -- we invent a new datatype which uses phantom types.
916 newtype Core a = MkC CoreExpr
919 rep2 :: Name -> [ CoreExpr ] -> DsM (Core a)
920 rep2 n xs = do { id <- dsLookupGlobalId n
921 ; return (MkC (foldl App (Var id) xs)) }
923 -- Then we make "repConstructors" which use the phantom types for each of the
924 -- smart constructors of the Meta.Meta datatypes.
927 -- %*********************************************************************
929 -- The 'smart constructors'
931 -- %*********************************************************************
933 --------------- Patterns -----------------
934 repPlit :: Core M.Lit -> DsM (Core M.Pat)
935 repPlit (MkC l) = rep2 litPName [l]
937 repPvar :: Core String -> DsM (Core M.Pat)
938 repPvar (MkC s) = rep2 varPName [s]
940 repPtup :: Core [M.Pat] -> DsM (Core M.Pat)
941 repPtup (MkC ps) = rep2 tupPName [ps]
943 repPcon :: Core String -> Core [M.Pat] -> DsM (Core M.Pat)
944 repPcon (MkC s) (MkC ps) = rep2 conPName [s, ps]
946 repPrec :: Core String -> Core [(String,M.Pat)] -> DsM (Core M.Pat)
947 repPrec (MkC c) (MkC rps) = rep2 recPName [c,rps]
949 repPtilde :: Core M.Pat -> DsM (Core M.Pat)
950 repPtilde (MkC p) = rep2 tildePName [p]
952 repPaspat :: Core String -> Core M.Pat -> DsM (Core M.Pat)
953 repPaspat (MkC s) (MkC p) = rep2 asPName [s, p]
955 repPwild :: DsM (Core M.Pat)
956 repPwild = rep2 wildPName []
958 --------------- Expressions -----------------
959 repVarOrCon :: Name -> Core String -> DsM (Core M.ExpQ)
960 repVarOrCon vc str | isDataOcc (nameOccName vc) = repCon str
961 | otherwise = repVar str
963 repVar :: Core String -> DsM (Core M.ExpQ)
964 repVar (MkC s) = rep2 varEName [s]
966 repCon :: Core String -> DsM (Core M.ExpQ)
967 repCon (MkC s) = rep2 conEName [s]
969 repLit :: Core M.Lit -> DsM (Core M.ExpQ)
970 repLit (MkC c) = rep2 litEName [c]
972 repApp :: Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
973 repApp (MkC x) (MkC y) = rep2 appEName [x,y]
975 repLam :: Core [M.Pat] -> Core M.ExpQ -> DsM (Core M.ExpQ)
976 repLam (MkC ps) (MkC e) = rep2 lamEName [ps, e]
978 repTup :: Core [M.ExpQ] -> DsM (Core M.ExpQ)
979 repTup (MkC es) = rep2 tupEName [es]
981 repCond :: Core M.ExpQ -> Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
982 repCond (MkC x) (MkC y) (MkC z) = rep2 condEName [x,y,z]
984 repLetE :: Core [M.DecQ] -> Core M.ExpQ -> DsM (Core M.ExpQ)
985 repLetE (MkC ds) (MkC e) = rep2 letEName [ds, e]
987 repCaseE :: Core M.ExpQ -> Core [M.MatchQ] -> DsM( Core M.ExpQ)
988 repCaseE (MkC e) (MkC ms) = rep2 caseEName [e, ms]
990 repDoE :: Core [M.StmtQ] -> DsM (Core M.ExpQ)
991 repDoE (MkC ss) = rep2 doEName [ss]
993 repComp :: Core [M.StmtQ] -> DsM (Core M.ExpQ)
994 repComp (MkC ss) = rep2 compEName [ss]
996 repListExp :: Core [M.ExpQ] -> DsM (Core M.ExpQ)
997 repListExp (MkC es) = rep2 listEName [es]
999 repSigExp :: Core M.ExpQ -> Core M.TypeQ -> DsM (Core M.ExpQ)
1000 repSigExp (MkC e) (MkC t) = rep2 sigEName [e,t]
1002 repRecCon :: Core String -> Core [M.FieldExp]-> DsM (Core M.ExpQ)
1003 repRecCon (MkC c) (MkC fs) = rep2 recCName [c,fs]
1005 repRecUpd :: Core M.ExpQ -> Core [M.FieldExp] -> DsM (Core M.ExpQ)
1006 repRecUpd (MkC e) (MkC fs) = rep2 recUpdEName [e,fs]
1008 repInfixApp :: Core M.ExpQ -> Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1009 repInfixApp (MkC x) (MkC y) (MkC z) = rep2 infixAppName [x,y,z]
1011 repSectionL :: Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1012 repSectionL (MkC x) (MkC y) = rep2 sectionLName [x,y]
1014 repSectionR :: Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1015 repSectionR (MkC x) (MkC y) = rep2 sectionRName [x,y]
1017 ------------ Right hand sides (guarded expressions) ----
1018 repGuarded :: Core [(M.ExpQ, M.ExpQ)] -> DsM (Core M.BodyQ)
1019 repGuarded (MkC pairs) = rep2 guardedBName [pairs]
1021 repNormal :: Core M.ExpQ -> DsM (Core M.BodyQ)
1022 repNormal (MkC e) = rep2 normalBName [e]
1024 ------------- Stmts -------------------
1025 repBindSt :: Core M.Pat -> Core M.ExpQ -> DsM (Core M.StmtQ)
1026 repBindSt (MkC p) (MkC e) = rep2 bindSName [p,e]
1028 repLetSt :: Core [M.DecQ] -> DsM (Core M.StmtQ)
1029 repLetSt (MkC ds) = rep2 letSName [ds]
1031 repNoBindSt :: Core M.ExpQ -> DsM (Core M.StmtQ)
1032 repNoBindSt (MkC e) = rep2 noBindSName [e]
1034 -------------- Range (Arithmetic sequences) -----------
1035 repFrom :: Core M.ExpQ -> DsM (Core M.ExpQ)
1036 repFrom (MkC x) = rep2 fromEName [x]
1038 repFromThen :: Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1039 repFromThen (MkC x) (MkC y) = rep2 fromThenEName [x,y]
1041 repFromTo :: Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1042 repFromTo (MkC x) (MkC y) = rep2 fromToEName [x,y]
1044 repFromThenTo :: Core M.ExpQ -> Core M.ExpQ -> Core M.ExpQ -> DsM (Core M.ExpQ)
1045 repFromThenTo (MkC x) (MkC y) (MkC z) = rep2 fromThenToEName [x,y,z]
1047 ------------ Match and Clause Tuples -----------
1048 repMatch :: Core M.Pat -> Core M.BodyQ -> Core [M.DecQ] -> DsM (Core M.MatchQ)
1049 repMatch (MkC p) (MkC bod) (MkC ds) = rep2 matchName [p, bod, ds]
1051 repClause :: Core [M.Pat] -> Core M.BodyQ -> Core [M.DecQ] -> DsM (Core M.ClauseQ)
1052 repClause (MkC ps) (MkC bod) (MkC ds) = rep2 clauseName [ps, bod, ds]
1054 -------------- Dec -----------------------------
1055 repVal :: Core M.Pat -> Core M.BodyQ -> Core [M.DecQ] -> DsM (Core M.DecQ)
1056 repVal (MkC p) (MkC b) (MkC ds) = rep2 valDName [p, b, ds]
1058 repFun :: Core String -> Core [M.ClauseQ] -> DsM (Core M.DecQ)
1059 repFun (MkC nm) (MkC b) = rep2 funDName [nm, b]
1061 repData :: Core M.CxtQ -> Core String -> Core [String] -> Core [M.ConQ] -> Core [String] -> DsM (Core M.DecQ)
1062 repData (MkC cxt) (MkC nm) (MkC tvs) (MkC cons) (MkC derivs)
1063 = rep2 dataDName [cxt, nm, tvs, cons, derivs]
1065 repNewtype :: Core M.CxtQ -> Core String -> Core [String] -> Core M.ConQ -> Core [String] -> DsM (Core M.DecQ)
1066 repNewtype (MkC cxt) (MkC nm) (MkC tvs) (MkC con) (MkC derivs)
1067 = rep2 newtypeDName [cxt, nm, tvs, con, derivs]
1069 repTySyn :: Core String -> Core [String] -> Core M.TypeQ -> DsM (Core M.DecQ)
1070 repTySyn (MkC nm) (MkC tvs) (MkC rhs) = rep2 tySynDName [nm, tvs, rhs]
1072 repInst :: Core M.CxtQ -> Core M.TypeQ -> Core [M.DecQ] -> DsM (Core M.DecQ)
1073 repInst (MkC cxt) (MkC ty) (MkC ds) = rep2 instanceDName [cxt, ty, ds]
1075 repClass :: Core M.CxtQ -> Core String -> Core [String] -> Core [M.DecQ] -> DsM (Core M.DecQ)
1076 repClass (MkC cxt) (MkC cls) (MkC tvs) (MkC ds) = rep2 classDName [cxt, cls, tvs, ds]
1078 repProto :: Core String -> Core M.TypeQ -> DsM (Core M.DecQ)
1079 repProto (MkC s) (MkC ty) = rep2 sigDName [s, ty]
1081 repCtxt :: Core [M.TypeQ] -> DsM (Core M.CxtQ)
1082 repCtxt (MkC tys) = rep2 cxtName [tys]
1084 repConstr :: Core String -> HsConDetails Name (BangType Name)
1085 -> DsM (Core M.ConQ)
1086 repConstr con (PrefixCon ps)
1087 = do arg_tys <- mapM repBangTy ps
1088 arg_tys1 <- coreList strictTypeQTyConName arg_tys
1089 rep2 normalCName [unC con, unC arg_tys1]
1090 repConstr con (RecCon ips)
1091 = do arg_vs <- mapM lookupOcc (map fst ips)
1092 arg_tys <- mapM repBangTy (map snd ips)
1093 arg_vtys <- zipWithM (\x y -> rep2 varStrictTypeName [unC x, unC y])
1095 arg_vtys' <- coreList varStrictTypeQTyConName arg_vtys
1096 rep2 recCName [unC con, unC arg_vtys']
1097 repConstr con (InfixCon st1 st2)
1098 = do arg1 <- repBangTy st1
1099 arg2 <- repBangTy st2
1100 rep2 infixCName [unC arg1, unC con, unC arg2]
1102 ------------ Types -------------------
1104 repTForall :: Core [String] -> Core M.CxtQ -> Core M.TypeQ -> DsM (Core M.TypeQ)
1105 repTForall (MkC tvars) (MkC ctxt) (MkC ty)
1106 = rep2 forallTName [tvars, ctxt, ty]
1108 repTvar :: Core String -> DsM (Core M.TypeQ)
1109 repTvar (MkC s) = rep2 varTName [s]
1111 repTapp :: Core M.TypeQ -> Core M.TypeQ -> DsM (Core M.TypeQ)
1112 repTapp (MkC t1) (MkC t2) = rep2 appTName [t1,t2]
1114 repTapps :: Core M.TypeQ -> [Core M.TypeQ] -> DsM (Core M.TypeQ)
1115 repTapps f [] = return f
1116 repTapps f (t:ts) = do { f1 <- repTapp f t; repTapps f1 ts }
1118 --------- Type constructors --------------
1120 repNamedTyCon :: Core String -> DsM (Core M.TypeQ)
1121 repNamedTyCon (MkC s) = rep2 conTName [s]
1123 repTupleTyCon :: Int -> DsM (Core M.TypeQ)
1124 -- Note: not Core Int; it's easier to be direct here
1125 repTupleTyCon i = rep2 tupleTName [mkIntExpr (fromIntegral i)]
1127 repArrowTyCon :: DsM (Core M.TypeQ)
1128 repArrowTyCon = rep2 arrowTName []
1130 repListTyCon :: DsM (Core M.TypeQ)
1131 repListTyCon = rep2 listTName []
1134 ----------------------------------------------------------
1137 repLiteral :: HsLit -> DsM (Core M.Lit)
1139 = do lit' <- case lit of
1140 HsIntPrim i -> return $ HsInteger i
1141 HsInt i -> return $ HsInteger i
1142 HsFloatPrim r -> do rat_ty <- lookupType rationalTyConName
1143 return $ HsRat r rat_ty
1144 HsDoublePrim r -> do rat_ty <- lookupType rationalTyConName
1145 return $ HsRat r rat_ty
1147 lit_expr <- dsLit lit'
1148 rep2 lit_name [lit_expr]
1150 lit_name = case lit of
1151 HsInteger _ -> integerLName
1152 HsInt _ -> integerLName
1153 HsIntPrim _ -> intPrimLName
1154 HsFloatPrim _ -> floatPrimLName
1155 HsDoublePrim _ -> doublePrimLName
1156 HsChar _ -> charLName
1157 HsString _ -> stringLName
1158 HsRat _ _ -> rationalLName
1160 uh_oh = pprPanic "DsMeta.repLiteral: trying to represent exotic literal"
1163 repOverloadedLiteral :: HsOverLit -> DsM (Core M.Lit)
1164 repOverloadedLiteral (HsIntegral i _) = repLiteral (HsInteger i)
1165 repOverloadedLiteral (HsFractional f _) = do { rat_ty <- lookupType rationalTyConName ;
1166 repLiteral (HsRat f rat_ty) }
1167 -- The type Rational will be in the environment, becuase
1168 -- the smart constructor 'THSyntax.rationalL' uses it in its type,
1169 -- and rationalL is sucked in when any TH stuff is used
1171 --------------- Miscellaneous -------------------
1173 repLift :: Core e -> DsM (Core M.ExpQ)
1174 repLift (MkC x) = rep2 liftName [x]
1176 repGensym :: Core String -> DsM (Core (M.Q String))
1177 repGensym (MkC lit_str) = rep2 gensymName [lit_str]
1179 repBindQ :: Type -> Type -- a and b
1180 -> Core (M.Q a) -> Core (a -> M.Q b) -> DsM (Core (M.Q b))
1181 repBindQ ty_a ty_b (MkC x) (MkC y)
1182 = rep2 bindQName [Type ty_a, Type ty_b, x, y]
1184 repSequenceQ :: Type -> Core [M.Q a] -> DsM (Core (M.Q [a]))
1185 repSequenceQ ty_a (MkC list)
1186 = rep2 sequenceQName [Type ty_a, list]
1188 ------------ Lists and Tuples -------------------
1189 -- turn a list of patterns into a single pattern matching a list
1191 coreList :: Name -- Of the TyCon of the element type
1192 -> [Core a] -> DsM (Core [a])
1194 = do { elt_ty <- lookupType tc_name; return (coreList' elt_ty es) }
1196 coreList' :: Type -- The element type
1197 -> [Core a] -> Core [a]
1198 coreList' elt_ty es = MkC (mkListExpr elt_ty (map unC es ))
1200 nonEmptyCoreList :: [Core a] -> Core [a]
1201 -- The list must be non-empty so we can get the element type
1202 -- Otherwise use coreList
1203 nonEmptyCoreList [] = panic "coreList: empty argument"
1204 nonEmptyCoreList xs@(MkC x:_) = MkC (mkListExpr (exprType x) (map unC xs))
1206 corePair :: (Core a, Core b) -> Core (a,b)
1207 corePair (MkC x, MkC y) = MkC (mkCoreTup [x,y])
1209 coreStringLit :: String -> DsM (Core String)
1210 coreStringLit s = do { z <- mkStringLit s; return(MkC z) }
1212 coreVar :: Id -> Core String -- The Id has type String
1213 coreVar id = MkC (Var id)
1217 -- %************************************************************************
1219 -- The known-key names for Template Haskell
1221 -- %************************************************************************
1223 -- To add a name, do three things
1225 -- 1) Allocate a key
1227 -- 3) Add the name to knownKeyNames
1229 templateHaskellNames :: NameSet
1230 -- The names that are implicitly mentioned by ``bracket''
1231 -- Should stay in sync with the import list of DsMeta
1233 templateHaskellNames = mkNameSet [
1234 returnQName, bindQName, sequenceQName, gensymName, liftName,
1236 charLName, stringLName, integerLName, intPrimLName,
1237 floatPrimLName, doublePrimLName, rationalLName,
1239 litPName, varPName, tupPName, conPName, tildePName,
1240 asPName, wildPName, recPName,
1248 varEName, conEName, litEName, appEName, infixEName,
1249 infixAppName, sectionLName, sectionRName, lamEName, tupEName,
1250 condEName, letEName, caseEName, doEName, compEName,
1251 fromEName, fromThenEName, fromToEName, fromThenToEName,
1252 listEName, sigEName, recConEName, recUpdEName,
1256 guardedBName, normalBName,
1258 bindSName, letSName, noBindSName, parSName,
1260 funDName, valDName, dataDName, newtypeDName, tySynDName,
1261 classDName, instanceDName, sigDName,
1265 isStrictName, notStrictName,
1267 normalCName, recCName, infixCName,
1273 forallTName, varTName, conTName, appTName,
1274 tupleTName, arrowTName, listTName,
1277 qTyConName, patTyConName, fieldPatTyConName, matchQTyConName,
1278 clauseQTyConName, expQTyConName, fieldExpTyConName, stmtQTyConName,
1279 decQTyConName, conQTyConName, strictTypeQTyConName,
1280 varStrictTypeQTyConName, typeQTyConName, expTyConName, decTyConName,
1281 typeTyConName, matchTyConName, clauseTyConName]
1283 varQual = mk_known_key_name OccName.varName
1284 tcQual = mk_known_key_name OccName.tcName
1287 -- NB: the THSyntax module comes from the "haskell-src" package
1288 thModule = mkThPkgModule mETA_META_Name
1290 mk_known_key_name space str uniq
1291 = mkKnownKeyExternalName thModule (mkOccFS space str) uniq
1293 returnQName = varQual FSLIT("returnQ") returnQIdKey
1294 bindQName = varQual FSLIT("bindQ") bindQIdKey
1295 sequenceQName = varQual FSLIT("sequenceQ") sequenceQIdKey
1296 gensymName = varQual FSLIT("gensym") gensymIdKey
1297 liftName = varQual FSLIT("lift") liftIdKey
1300 charLName = varQual FSLIT("charL") charLIdKey
1301 stringLName = varQual FSLIT("stringL") stringLIdKey
1302 integerLName = varQual FSLIT("integerL") integerLIdKey
1303 intPrimLName = varQual FSLIT("intPrimL") intPrimLIdKey
1304 floatPrimLName = varQual FSLIT("floatPrimL") floatPrimLIdKey
1305 doublePrimLName = varQual FSLIT("doublePrimL") doublePrimLIdKey
1306 rationalLName = varQual FSLIT("rationalL") rationalLIdKey
1309 litPName = varQual FSLIT("litP") litPIdKey
1310 varPName = varQual FSLIT("varP") varPIdKey
1311 tupPName = varQual FSLIT("tupP") tupPIdKey
1312 conPName = varQual FSLIT("conP") conPIdKey
1313 tildePName = varQual FSLIT("tildeP") tildePIdKey
1314 asPName = varQual FSLIT("asP") asPIdKey
1315 wildPName = varQual FSLIT("wildP") wildPIdKey
1316 recPName = varQual FSLIT("recP") recPIdKey
1318 -- type FieldPat = ...
1319 fieldPatName = varQual FSLIT("fieldPat") fieldPatIdKey
1322 matchName = varQual FSLIT("match") matchIdKey
1324 -- data Clause = ...
1325 clauseName = varQual FSLIT("clause") clauseIdKey
1328 varEName = varQual FSLIT("varE") varEIdKey
1329 conEName = varQual FSLIT("conE") conEIdKey
1330 litEName = varQual FSLIT("litE") litEIdKey
1331 appEName = varQual FSLIT("appE") appEIdKey
1332 infixEName = varQual FSLIT("infixE") infixEIdKey
1333 infixAppName = varQual FSLIT("infixApp") infixAppIdKey
1334 sectionLName = varQual FSLIT("sectionL") sectionLIdKey
1335 sectionRName = varQual FSLIT("sectionR") sectionRIdKey
1336 lamEName = varQual FSLIT("lamE") lamEIdKey
1337 tupEName = varQual FSLIT("tupE") tupEIdKey
1338 condEName = varQual FSLIT("condE") condEIdKey
1339 letEName = varQual FSLIT("letE") letEIdKey
1340 caseEName = varQual FSLIT("caseE") caseEIdKey
1341 doEName = varQual FSLIT("doE") doEIdKey
1342 compEName = varQual FSLIT("compE") compEIdKey
1343 -- ArithSeq skips a level
1344 fromEName = varQual FSLIT("fromE") fromEIdKey
1345 fromThenEName = varQual FSLIT("fromThenE") fromThenEIdKey
1346 fromToEName = varQual FSLIT("fromToE") fromToEIdKey
1347 fromThenToEName = varQual FSLIT("fromThenToE") fromThenToEIdKey
1349 listEName = varQual FSLIT("listE") listEIdKey
1350 sigEName = varQual FSLIT("sigE") sigEIdKey
1351 recConEName = varQual FSLIT("recConE") recConEIdKey
1352 recUpdEName = varQual FSLIT("recUpdE") recUpdEIdKey
1354 -- type FieldExp = ...
1355 fieldExpName = varQual FSLIT("fieldExp") fieldExpIdKey
1358 guardedBName = varQual FSLIT("guardedB") guardedBIdKey
1359 normalBName = varQual FSLIT("normalB") normalBIdKey
1362 bindSName = varQual FSLIT("bindS") bindSIdKey
1363 letSName = varQual FSLIT("letS") letSIdKey
1364 noBindSName = varQual FSLIT("noBindS") noBindSIdKey
1365 parSName = varQual FSLIT("parS") parSIdKey
1368 funDName = varQual FSLIT("funD") funDIdKey
1369 valDName = varQual FSLIT("valD") valDIdKey
1370 dataDName = varQual FSLIT("dataD") dataDIdKey
1371 newtypeDName = varQual FSLIT("newtypeD") newtypeDIdKey
1372 tySynDName = varQual FSLIT("tySynD") tySynDIdKey
1373 classDName = varQual FSLIT("classD") classDIdKey
1374 instanceDName = varQual FSLIT("instanceD") instanceDIdKey
1375 sigDName = varQual FSLIT("sigD") sigDIdKey
1378 cxtName = varQual FSLIT("cxt") cxtIdKey
1380 -- data Strict = ...
1381 isStrictName = varQual FSLIT("isStrict") isStrictKey
1382 notStrictName = varQual FSLIT("notStrict") notStrictKey
1385 normalCName = varQual FSLIT("normalC") normalCIdKey
1386 recCName = varQual FSLIT("recC") recCIdKey
1387 infixCName = varQual FSLIT("infixC") infixCIdKey
1389 -- type StrictType = ...
1390 strictTypeName = varQual FSLIT("strictType") strictTKey
1392 -- type VarStrictType = ...
1393 varStrictTypeName = varQual FSLIT("varStrictType") varStrictTKey
1396 forallTName = varQual FSLIT("forallT") forallTIdKey
1397 varTName = varQual FSLIT("varT") varTIdKey
1398 conTName = varQual FSLIT("conT") conTIdKey
1399 tupleTName = varQual FSLIT("tupleT") tupleTIdKey
1400 arrowTName = varQual FSLIT("arrowT") arrowTIdKey
1401 listTName = varQual FSLIT("listT") listTIdKey
1402 appTName = varQual FSLIT("appT") appTIdKey
1404 qTyConName = tcQual FSLIT("Q") qTyConKey
1405 patTyConName = tcQual FSLIT("Pat") patTyConKey
1406 fieldPatTyConName = tcQual FSLIT("FieldPat") fieldPatTyConKey
1407 matchQTyConName = tcQual FSLIT("MatchQ") matchQTyConKey
1408 clauseQTyConName = tcQual FSLIT("ClauseQ") clauseQTyConKey
1409 expQTyConName = tcQual FSLIT("ExpQ") expQTyConKey
1410 fieldExpTyConName = tcQual FSLIT("FieldExp") fieldExpTyConKey
1411 stmtQTyConName = tcQual FSLIT("StmtQ") stmtQTyConKey
1412 decQTyConName = tcQual FSLIT("DecQ") decQTyConKey
1413 conQTyConName = tcQual FSLIT("ConQ") conQTyConKey
1414 strictTypeQTyConName = tcQual FSLIT("StrictTypeQ") strictTypeQTyConKey
1415 varStrictTypeQTyConName = tcQual FSLIT("VarStrictTypeQ") varStrictTypeQTyConKey
1416 typeQTyConName = tcQual FSLIT("TypeQ") typeQTyConKey
1418 expTyConName = tcQual FSLIT("Exp") expTyConKey
1419 decTyConName = tcQual FSLIT("Dec") decTyConKey
1420 typeTyConName = tcQual FSLIT("Type") typeTyConKey
1421 matchTyConName = tcQual FSLIT("Match") matchTyConKey
1422 clauseTyConName = tcQual FSLIT("Clause") clauseTyConKey
1424 -- TyConUniques available: 100-119
1425 -- Check in PrelNames if you want to change this
1427 expTyConKey = mkPreludeTyConUnique 100
1428 matchTyConKey = mkPreludeTyConUnique 101
1429 clauseTyConKey = mkPreludeTyConUnique 102
1430 qTyConKey = mkPreludeTyConUnique 103
1431 expQTyConKey = mkPreludeTyConUnique 104
1432 decQTyConKey = mkPreludeTyConUnique 105
1433 patTyConKey = mkPreludeTyConUnique 106
1434 matchQTyConKey = mkPreludeTyConUnique 107
1435 clauseQTyConKey = mkPreludeTyConUnique 108
1436 stmtQTyConKey = mkPreludeTyConUnique 109
1437 conQTyConKey = mkPreludeTyConUnique 110
1438 typeQTyConKey = mkPreludeTyConUnique 111
1439 typeTyConKey = mkPreludeTyConUnique 112
1440 decTyConKey = mkPreludeTyConUnique 113
1441 varStrictTypeQTyConKey = mkPreludeTyConUnique 114
1442 strictTypeQTyConKey = mkPreludeTyConUnique 115
1443 fieldExpTyConKey = mkPreludeTyConUnique 116
1444 fieldPatTyConKey = mkPreludeTyConUnique 117
1446 -- IdUniques available: 200-299
1447 -- If you want to change this, make sure you check in PrelNames
1449 returnQIdKey = mkPreludeMiscIdUnique 200
1450 bindQIdKey = mkPreludeMiscIdUnique 201
1451 sequenceQIdKey = mkPreludeMiscIdUnique 202
1452 gensymIdKey = mkPreludeMiscIdUnique 203
1453 liftIdKey = mkPreludeMiscIdUnique 204
1456 charLIdKey = mkPreludeMiscIdUnique 210
1457 stringLIdKey = mkPreludeMiscIdUnique 211
1458 integerLIdKey = mkPreludeMiscIdUnique 212
1459 intPrimLIdKey = mkPreludeMiscIdUnique 213
1460 floatPrimLIdKey = mkPreludeMiscIdUnique 214
1461 doublePrimLIdKey = mkPreludeMiscIdUnique 215
1462 rationalLIdKey = mkPreludeMiscIdUnique 216
1465 litPIdKey = mkPreludeMiscIdUnique 220
1466 varPIdKey = mkPreludeMiscIdUnique 221
1467 tupPIdKey = mkPreludeMiscIdUnique 222
1468 conPIdKey = mkPreludeMiscIdUnique 223
1469 tildePIdKey = mkPreludeMiscIdUnique 224
1470 asPIdKey = mkPreludeMiscIdUnique 225
1471 wildPIdKey = mkPreludeMiscIdUnique 226
1472 recPIdKey = mkPreludeMiscIdUnique 227
1474 -- type FieldPat = ...
1475 fieldPatIdKey = mkPreludeMiscIdUnique 228
1478 matchIdKey = mkPreludeMiscIdUnique 229
1480 -- data Clause = ...
1481 clauseIdKey = mkPreludeMiscIdUnique 230
1484 varEIdKey = mkPreludeMiscIdUnique 240
1485 conEIdKey = mkPreludeMiscIdUnique 241
1486 litEIdKey = mkPreludeMiscIdUnique 242
1487 appEIdKey = mkPreludeMiscIdUnique 243
1488 infixEIdKey = mkPreludeMiscIdUnique 244
1489 infixAppIdKey = mkPreludeMiscIdUnique 245
1490 sectionLIdKey = mkPreludeMiscIdUnique 246
1491 sectionRIdKey = mkPreludeMiscIdUnique 247
1492 lamEIdKey = mkPreludeMiscIdUnique 248
1493 tupEIdKey = mkPreludeMiscIdUnique 249
1494 condEIdKey = mkPreludeMiscIdUnique 250
1495 letEIdKey = mkPreludeMiscIdUnique 251
1496 caseEIdKey = mkPreludeMiscIdUnique 252
1497 doEIdKey = mkPreludeMiscIdUnique 253
1498 compEIdKey = mkPreludeMiscIdUnique 254
1499 fromEIdKey = mkPreludeMiscIdUnique 255
1500 fromThenEIdKey = mkPreludeMiscIdUnique 256
1501 fromToEIdKey = mkPreludeMiscIdUnique 257
1502 fromThenToEIdKey = mkPreludeMiscIdUnique 258
1503 listEIdKey = mkPreludeMiscIdUnique 259
1504 sigEIdKey = mkPreludeMiscIdUnique 260
1505 recConEIdKey = mkPreludeMiscIdUnique 261
1506 recUpdEIdKey = mkPreludeMiscIdUnique 262
1508 -- type FieldExp = ...
1509 fieldExpIdKey = mkPreludeMiscIdUnique 265
1512 guardedBIdKey = mkPreludeMiscIdUnique 266
1513 normalBIdKey = mkPreludeMiscIdUnique 267
1516 bindSIdKey = mkPreludeMiscIdUnique 268
1517 letSIdKey = mkPreludeMiscIdUnique 269
1518 noBindSIdKey = mkPreludeMiscIdUnique 270
1519 parSIdKey = mkPreludeMiscIdUnique 271
1522 funDIdKey = mkPreludeMiscIdUnique 272
1523 valDIdKey = mkPreludeMiscIdUnique 273
1524 dataDIdKey = mkPreludeMiscIdUnique 274
1525 newtypeDIdKey = mkPreludeMiscIdUnique 275
1526 tySynDIdKey = mkPreludeMiscIdUnique 276
1527 classDIdKey = mkPreludeMiscIdUnique 277
1528 instanceDIdKey = mkPreludeMiscIdUnique 278
1529 sigDIdKey = mkPreludeMiscIdUnique 279
1532 cxtIdKey = mkPreludeMiscIdUnique 280
1534 -- data Strict = ...
1535 isStrictKey = mkPreludeMiscIdUnique 281
1536 notStrictKey = mkPreludeMiscIdUnique 282
1539 normalCIdKey = mkPreludeMiscIdUnique 283
1540 recCIdKey = mkPreludeMiscIdUnique 284
1541 infixCIdKey = mkPreludeMiscIdUnique 285
1543 -- type StrictType = ...
1544 strictTKey = mkPreludeMiscIdUnique 2286
1546 -- type VarStrictType = ...
1547 varStrictTKey = mkPreludeMiscIdUnique 287
1550 forallTIdKey = mkPreludeMiscIdUnique 290
1551 varTIdKey = mkPreludeMiscIdUnique 291
1552 conTIdKey = mkPreludeMiscIdUnique 292
1553 tupleTIdKey = mkPreludeMiscIdUnique 294
1554 arrowTIdKey = mkPreludeMiscIdUnique 295
1555 listTIdKey = mkPreludeMiscIdUnique 296
1556 appTIdKey = mkPreludeMiscIdUnique 293
1558 -- %************************************************************************
1562 -- %************************************************************************
1564 -- It is rather usatisfactory that we don't have a SrcLoc
1565 addDsWarn :: SDoc -> DsM ()
1566 addDsWarn msg = dsWarn (noSrcLoc, msg)