TcHsSyn.hs 63.7 KB
Newer Older
Austin Seipp's avatar
Austin Seipp committed
1 2 3 4
{-
(c) The University of Glasgow 2006
(c) The AQUA Project, Glasgow University, 1996-1998

5 6

TcHsSyn: Specialisations of the @HsSyn@ syntax for the typechecker
7 8 9

This module is an extension of @HsSyn@ syntax, for use in the type
checker.
Austin Seipp's avatar
Austin Seipp committed
10
-}
11

12 13
{-# LANGUAGE CPP #-}

14
module TcHsSyn (
15 16 17 18 19
        mkHsConApp, mkHsDictLet, mkHsApp,
        hsLitType, hsLPatType, hsPatType,
        mkHsAppTy, mkSimpleHsAlt,
        nlHsIntLit,
        shortCutLit, hsOverLitName,
20
        conLikeResTy,
21 22 23 24 25 26 27

        -- re-exported from TcMonad
        TcId, TcIdSet,

        zonkTopDecls, zonkTopExpr, zonkTopLExpr,
        zonkTopBndrs, zonkTyBndrsX,
        emptyZonkEnv, mkEmptyZonkEnv, mkTyVarZonkEnv,
28
        zonkTcTypeToType, zonkTcTypeToTypes, zonkTyVarOcc,
29 30
  ) where

31
#include "HsVersions.h"
32

33
import HsSyn
34
import Id
35
import TcRnMonad
36
import PrelNames
37
import TypeRep     -- We can see the representation of types
38
import TcType
39
import RdrName ( RdrName, rdrNameOcc )
40
import TcMType ( defaultKindVarToStar, zonkQuantifiedTyVar, writeMetaTyVar )
41
import TcEvidence
42
import Coercion
43 44
import TysPrim
import TysWiredIn
dreixel's avatar
dreixel committed
45
import Type
46
import ConLike
47
import DataCon
48
import PatSyn( patSynInstResTy )
49
import Name
50
import NameSet
51
import Var
52
import VarSet
53
import VarEnv
54
import DynFlags
55
import Literal
56 57 58
import BasicTypes
import Maybes
import SrcLoc
sof's avatar
sof committed
59
import Bag
60
import FastString
sof's avatar
sof committed
61
import Outputable
62
import Util
63
#if __GLASGOW_HASKELL__ < 709
cactus's avatar
cactus committed
64
import Data.Traversable ( traverse )
65
#endif
66

Austin Seipp's avatar
Austin Seipp committed
67 68 69
{-
************************************************************************
*                                                                      *
70
\subsection[mkFailurePair]{Code for pattern-matching and other failures}
Austin Seipp's avatar
Austin Seipp committed
71 72
*                                                                      *
************************************************************************
73

74
Note: If @hsLPatType@ doesn't bear a strong resemblance to @exprType@,
75
then something is wrong.
Austin Seipp's avatar
Austin Seipp committed
76 77
-}

78 79 80
hsLPatType :: OutPat Id -> Type
hsLPatType (L _ pat) = hsPatType pat

Ian Lynagh's avatar
Ian Lynagh committed
81 82 83 84 85 86 87 88 89
hsPatType :: Pat Id -> Type
hsPatType (ParPat pat)                = hsLPatType pat
hsPatType (WildPat ty)                = ty
hsPatType (VarPat var)                = idType var
hsPatType (BangPat pat)               = hsLPatType pat
hsPatType (LazyPat pat)               = hsLPatType pat
hsPatType (LitPat lit)                = hsLitType lit
hsPatType (AsPat var _)               = idType (unLoc var)
hsPatType (ViewPat _ _ ty)            = ty
90 91
hsPatType (ListPat _ ty Nothing)      = mkListTy ty
hsPatType (ListPat _ _ (Just (ty,_))) = ty
Ian Lynagh's avatar
Ian Lynagh committed
92
hsPatType (PArrPat _ ty)              = mkPArrTy ty
93
hsPatType (TuplePat _ bx tys)         = mkTupleTy bx tys
94
hsPatType (ConPatOut { pat_con = L _ con, pat_arg_tys = tys })
95
                                      = conLikeResTy con tys
Ian Lynagh's avatar
Ian Lynagh committed
96
hsPatType (SigPatOut _ ty)            = ty
Alan Zimmerman's avatar
Alan Zimmerman committed
97
hsPatType (NPat (L _ lit) _ _)        = overLitType lit
Ian Lynagh's avatar
Ian Lynagh committed
98 99 100
hsPatType (NPlusKPat id _ _ _)        = idType (unLoc id)
hsPatType (CoPat _ _ ty)              = ty
hsPatType p                           = pprPanic "hsPatType" (ppr p)
101

102 103 104 105
conLikeResTy :: ConLike -> [Type] -> Type
conLikeResTy (RealDataCon con) tys = mkTyConApp (dataConTyCon con) tys
conLikeResTy (PatSynCon ps)    tys = patSynInstResTy ps tys

106
hsLitType :: HsLit -> TcType
107 108 109 110 111 112 113 114 115 116 117 118 119
hsLitType (HsChar _ _)       = charTy
hsLitType (HsCharPrim _ _)   = charPrimTy
hsLitType (HsString _ _)     = stringTy
hsLitType (HsStringPrim _ _) = addrPrimTy
hsLitType (HsInt _ _)        = intTy
hsLitType (HsIntPrim _ _)    = intPrimTy
hsLitType (HsWordPrim _ _)   = wordPrimTy
hsLitType (HsInt64Prim _ _)  = int64PrimTy
hsLitType (HsWord64Prim _ _) = word64PrimTy
hsLitType (HsInteger _ _ ty) = ty
hsLitType (HsRat _ ty)       = ty
hsLitType (HsFloatPrim _)    = floatPrimTy
hsLitType (HsDoublePrim _)   = doublePrimTy
120

Austin Seipp's avatar
Austin Seipp committed
121
-- Overloaded literals. Here mainly because it uses isIntTy etc
122

123
shortCutLit :: DynFlags -> OverLitVal -> TcType -> Maybe (HsExpr TcId)
124 125 126 127 128
shortCutLit dflags (HsIntegral src i) ty
  | isIntTy ty  && inIntRange  dflags i = Just (HsLit (HsInt src i))
  | isWordTy ty && inWordRange dflags i
                                   = Just (mkLit wordDataCon (HsWordPrim src i))
  | isIntegerTy ty = Just (HsLit (HsInteger src i ty))
129
  | otherwise = shortCutLit dflags (HsFractional (integralFractionalLit i)) ty
130 131 132 133 134
        -- The 'otherwise' case is important
        -- Consider (3 :: Float).  Syntactically it looks like an IntLit,
        -- so we'll call shortCutIntLit, but of course it's a float
        -- This can make a big difference for programs with a lot of
        -- literals, compiled without -O
135

136
shortCutLit _ (HsFractional f) ty
137 138
  | isFloatTy ty  = Just (mkLit floatDataCon  (HsFloatPrim f))
  | isDoubleTy ty = Just (mkLit doubleDataCon (HsDoublePrim f))
139 140
  | otherwise     = Nothing

141 142
shortCutLit _ (HsIsString src s) ty
  | isStringTy ty = Just (HsLit (HsString src s))
143 144 145 146 147 148 149 150 151 152 153
  | otherwise     = Nothing

mkLit :: DataCon -> HsLit -> HsExpr Id
mkLit con lit = HsApp (nlHsVar (dataConWrapId con)) (nlHsLit lit)

------------------------------
hsOverLitName :: OverLitVal -> Name
-- Get the canonical 'fromX' name for a particular OverLitVal
hsOverLitName (HsIntegral {})   = fromIntegerName
hsOverLitName (HsFractional {}) = fromRationalName
hsOverLitName (HsIsString {})   = fromStringName
154

Austin Seipp's avatar
Austin Seipp committed
155 156 157
{-
************************************************************************
*                                                                      *
158
\subsection[BackSubst-HsBinds]{Running a substitution over @HsBinds@}
Austin Seipp's avatar
Austin Seipp committed
159 160
*                                                                      *
************************************************************************
161

162 163
The rest of the zonking is done *after* typechecking.
The main zonking pass runs over the bindings
164 165 166

 a) to convert TcTyVars to TyVars etc, dereferencing any bindings etc
 b) convert unbound TcTyVar to Void
167
 c) convert each TcId to an Id by zonking its type
sof's avatar
sof committed
168

169 170
The type variables are converted by binding mutable tyvars to immutable ones
and then zonking as normal.
171

172 173 174
The Ids are converted by binding them in the normal Tc envt; that
way we maintain sharing; eg an Id is zonked at its binding site and they
all occurrences of that Id point to the common zonked copy
sof's avatar
sof committed
175

176
It's all pretty boring stuff, because HsSyn is such a large type, and
177
the environment manipulation is tiresome.
Austin Seipp's avatar
Austin Seipp committed
178
-}
179

180 181
type UnboundTyVarZonker = TcTyVar-> TcM Type
        -- How to zonk an unbound type variable
dreixel's avatar
dreixel committed
182 183
        -- Note [Zonking the LHS of a RULE]

184 185
data ZonkEnv
  = ZonkEnv
dreixel's avatar
dreixel committed
186
      UnboundTyVarZonker
187 188 189 190 191 192 193 194 195
      (TyVarEnv TyVar)          --
      (IdEnv    Var)            -- What variables are in scope
        -- Maps an Id or EvVar to its zonked version; both have the same Name
        -- Note that all evidence (coercion variables as well as dictionaries)
        --      are kept in the ZonkEnv
        -- Only *type* abstraction is done by side effect
        -- Is only consulted lazily; hence knot-tying

instance Outputable ZonkEnv where
196 197 198
  ppr (ZonkEnv _ _ty_env var_env) = vcat (map ppr (varEnvElts var_env))


Ian Lynagh's avatar
Ian Lynagh committed
199
emptyZonkEnv :: ZonkEnv
200 201 202 203
emptyZonkEnv = mkEmptyZonkEnv zonkTypeZapping

mkEmptyZonkEnv :: UnboundTyVarZonker -> ZonkEnv
mkEmptyZonkEnv zonker = ZonkEnv zonker emptyVarEnv emptyVarEnv
204

dreixel's avatar
dreixel committed
205
extendIdZonkEnv :: ZonkEnv -> [Var] -> ZonkEnv
206
extendIdZonkEnv (ZonkEnv zonk_ty ty_env id_env) ids
dreixel's avatar
dreixel committed
207
  = ZonkEnv zonk_ty ty_env (extendVarEnvList id_env [(id,id) | id <- ids])
208

dreixel's avatar
dreixel committed
209
extendIdZonkEnv1 :: ZonkEnv -> Var -> ZonkEnv
210
extendIdZonkEnv1 (ZonkEnv zonk_ty ty_env id_env) id
dreixel's avatar
dreixel committed
211
  = ZonkEnv zonk_ty ty_env (extendVarEnv id_env id id)
212

dreixel's avatar
dreixel committed
213 214 215 216
extendTyZonkEnv1 :: ZonkEnv -> TyVar -> ZonkEnv
extendTyZonkEnv1 (ZonkEnv zonk_ty ty_env id_env) ty
  = ZonkEnv zonk_ty (extendVarEnv ty_env ty ty) id_env

217 218 219
mkTyVarZonkEnv :: [TyVar] -> ZonkEnv
mkTyVarZonkEnv tvs = ZonkEnv zonkTypeZapping (mkVarEnv [(tv,tv) | tv <- tvs]) emptyVarEnv

dreixel's avatar
dreixel committed
220 221
setZonkType :: ZonkEnv -> UnboundTyVarZonker -> ZonkEnv
setZonkType (ZonkEnv _ ty_env id_env) zonk_ty = ZonkEnv zonk_ty ty_env id_env
222

223
zonkEnvIds :: ZonkEnv -> [Id]
dreixel's avatar
dreixel committed
224
zonkEnvIds (ZonkEnv _ _ id_env) = varEnvElts id_env
225 226

zonkIdOcc :: ZonkEnv -> TcId -> Id
227
-- Ids defined in this module should be in the envt;
228 229
-- ignore others.  (Actually, data constructors are also
-- not LocalVars, even when locally defined, but that is fine.)
230 231
-- (Also foreign-imported things aren't currently in the ZonkEnv;
--  that's ok because they don't need zonking.)
232 233
--
-- Actually, Template Haskell works in 'chunks' of declarations, and
234
-- an earlier chunk won't be in the 'env' that the zonking phase
235
-- carries around.  Instead it'll be in the tcg_gbl_env, already fully
236
-- zonked.  There's no point in looking it up there (except for error
237 238 239 240
-- checking), and it's not conveniently to hand; hence the simple
-- 'orElse' case in the LocalVar branch.
--
-- Even without template splices, in module Main, the checking of
241
-- 'main' is done as a separate chunk.
242
zonkIdOcc (ZonkEnv _zonk_ty _ty_env env) id
243
  | isLocalVar id = lookupVarEnv env id `orElse` id
244
  | otherwise     = id
245

Ian Lynagh's avatar
Ian Lynagh committed
246
zonkIdOccs :: ZonkEnv -> [TcId] -> [Id]
247
zonkIdOccs env ids = map (zonkIdOcc env) ids
248

249
-- zonkIdBndr is used *after* typechecking to get the Id's type
250
-- to its final form.  The TyVarEnv give
251 252
zonkIdBndr :: ZonkEnv -> TcId -> TcM Id
zonkIdBndr env id
ian@well-typed.com's avatar
ian@well-typed.com committed
253 254
  = do ty' <- zonkTcTypeToType env (idType id)
       return (Id.setIdType id ty')
255 256

zonkIdBndrs :: ZonkEnv -> [TcId] -> TcM [Id]
257
zonkIdBndrs env ids = mapM (zonkIdBndr env) ids
258 259 260

zonkTopBndrs :: [TcId] -> TcM [Id]
zonkTopBndrs ids = zonkIdBndrs emptyZonkEnv ids
261

262 263 264
zonkFieldOcc :: ZonkEnv -> FieldOcc TcId -> TcM (FieldOcc Id)
zonkFieldOcc env (FieldOcc lbl sel) = fmap (FieldOcc lbl) $ zonkIdBndr env sel

265
zonkEvBndrsX :: ZonkEnv -> [EvVar] -> TcM (ZonkEnv, [Var])
266
zonkEvBndrsX = mapAccumLM zonkEvBndrX
267 268 269 270 271

zonkEvBndrX :: ZonkEnv -> EvVar -> TcM (ZonkEnv, EvVar)
-- Works for dictionaries and coercions
zonkEvBndrX env var
  = do { var' <- zonkEvBndr env var
dreixel's avatar
dreixel committed
272
       ; return (extendIdZonkEnv1 env var', var') }
273 274 275 276

zonkEvBndr :: ZonkEnv -> EvVar -> TcM EvVar
-- Works for dictionaries and coercions
-- Does not extend the ZonkEnv
277
zonkEvBndr env var
278
  = do { let var_ty = varType var
279
       ; ty <-
280 281
           {-# SCC "zonkEvBndr_zonkTcTypeToType" #-}
           zonkTcTypeToType env var_ty
dreixel's avatar
dreixel committed
282
       ; return (setVarType var ty) }
283 284 285

zonkEvVarOcc :: ZonkEnv -> EvVar -> EvVar
zonkEvVarOcc env v = zonkIdOcc env v
dreixel's avatar
dreixel committed
286 287

zonkTyBndrsX :: ZonkEnv -> [TyVar] -> TcM (ZonkEnv, [TyVar])
288
zonkTyBndrsX = mapAccumLM zonkTyBndrX
dreixel's avatar
dreixel committed
289 290

zonkTyBndrX :: ZonkEnv -> TyVar -> TcM (ZonkEnv, TyVar)
291 292
-- This guarantees to return a TyVar (not a TcTyVar)
-- then we add it to the envt, so all occurrences are replaced
dreixel's avatar
dreixel committed
293 294
zonkTyBndrX env tv
  = do { ki <- zonkTcTypeToType env (tyVarKind tv)
295 296
       ; let tv' = mkTyVar (tyVarName tv) ki
       ; return (extendTyZonkEnv1 env tv', tv') }
297

298
zonkTopExpr :: HsExpr TcId -> TcM (HsExpr Id)
299 300
zonkTopExpr e = zonkExpr emptyZonkEnv e

301 302 303
zonkTopLExpr :: LHsExpr TcId -> TcM (LHsExpr Id)
zonkTopLExpr e = zonkLExpr emptyZonkEnv e

304
zonkTopDecls :: Bag EvBind
305 306 307
             -> LHsBinds TcId 
             -> Maybe (Located [LIE RdrName]) 
             -> NameSet
308
             -> [LRuleDecl TcId] -> [LVectDecl TcId] -> [LTcSpecPrag] -> [LForeignDecl TcId]
309
             -> TcM ([Id],
310
                     Bag EvBind,
cactus's avatar
cactus committed
311
                     LHsBinds Id,
312 313 314 315
                     [LForeignDecl Id],
                     [LTcSpecPrag],
                     [LRuleDecl    Id],
                     [LVectDecl    Id])
316
zonkTopDecls ev_binds binds export_ies sig_ns rules vects imp_specs fords
317
  = do  { (env1, ev_binds') <- zonkEvBinds emptyZonkEnv ev_binds
318

319 320
         -- Warn about missing signatures
         -- Do this only when we we have a type to offer
321
        ; warn_missing_sigs <- woptM Opt_WarnMissingSigs
322
        ; warn_only_exported <- woptM Opt_WarnMissingExportedSigs
323 324 325 326 327
        ; let export_occs  = maybe emptyBag
                                   (listToBag . map (rdrNameOcc . ieName . unLoc) . unLoc)
                                   export_ies
              sig_warn
                | warn_only_exported = topSigWarnIfExported export_occs sig_ns
328 329
                | warn_missing_sigs  = topSigWarn sig_ns
                | otherwise          = noSigWarn
330 331

        ; (env2, binds') <- zonkRecMonoBinds env1 sig_warn binds
332 333 334
                        -- Top level is implicitly recursive
        ; rules' <- zonkRules env2 rules
        ; vects' <- zonkVects env2 vects
335
        ; specs' <- zonkLTcSpecPrags env2 imp_specs
336 337
        ; fords' <- zonkForeignExports env2 fords
        ; return (zonkEnvIds env2, ev_binds', binds', fords', specs', rules', vects') }
338 339

---------------------------------------------
340 341 342 343
zonkLocalBinds :: ZonkEnv -> HsLocalBinds TcId -> TcM (ZonkEnv, HsLocalBinds Id)
zonkLocalBinds env EmptyLocalBinds
  = return (env, EmptyLocalBinds)

344 345 346 347
zonkLocalBinds _ (HsValBinds (ValBindsIn {}))
  = panic "zonkLocalBinds" -- Not in typechecker output

zonkLocalBinds env (HsValBinds vb@(ValBindsOut binds sigs))
348
  = do  { warn_missing_sigs <- woptM Opt_WarnMissingLocalSigs
349 350 351
        ; let sig_warn | not warn_missing_sigs = noSigWarn
                       | otherwise             = localSigWarn sig_ns
              sig_ns = getTypeSigNames vb
352
        ; (env1, new_binds) <- go env sig_warn binds
353 354 355 356
        ; return (env1, HsValBinds (ValBindsOut new_binds sigs)) }
  where
    go env _ []
      = return (env, [])
357
    go env sig_warn ((r,b):bs)
358
      = do { (env1, b')  <- zonkRecMonoBinds env sig_warn b
359 360
           ; (env2, bs') <- go env1 sig_warn bs
           ; return (env2, (r,b'):bs') }
361

ian@well-typed.com's avatar
ian@well-typed.com committed
362 363
zonkLocalBinds env (HsIPBinds (IPBinds binds dict_binds)) = do
    new_binds <- mapM (wrapLocM zonk_ip_bind) binds
364
    let
365
        env1 = extendIdZonkEnv env [ n | L _ (IPBind (Right n) _) <- new_binds]
ian@well-typed.com's avatar
ian@well-typed.com committed
366
    (env2, new_dict_binds) <- zonkTcEvBinds env1 dict_binds
367
    return (env2, HsIPBinds (IPBinds new_binds new_dict_binds))
368
  where
369
    zonk_ip_bind (IPBind n e)
ian@well-typed.com's avatar
ian@well-typed.com committed
370 371 372
        = do n' <- mapIPNameTc (zonkIdBndr env) n
             e' <- zonkLExpr env e
             return (IPBind n' e')
373

374
---------------------------------------------
375
zonkRecMonoBinds :: ZonkEnv -> SigWarn -> LHsBinds TcId -> TcM (ZonkEnv, LHsBinds Id)
376 377 378
zonkRecMonoBinds env sig_warn binds
 = fixM (\ ~(_, new_binds) -> do
        { let env1 = extendIdZonkEnv env (collectHsBindsBinders new_binds)
379
        ; binds' <- zonkMonoBinds env1 sig_warn binds
380 381
        ; return (env1, binds') })

382
---------------------------------------------
383
type SigWarn = Bool -> [Id] -> TcM ()
384 385 386 387 388 389
     -- Missing-signature warning
     -- The Bool is True for an AbsBinds, False otherwise

noSigWarn :: SigWarn
noSigWarn _ _ = return ()

390 391 392 393 394 395 396 397 398 399 400
topSigWarnIfExported :: Bag OccName -> NameSet -> SigWarn
topSigWarnIfExported exported sig_ns _ ids
  = mapM_ (topSigWarnIdIfExported exported sig_ns) ids

topSigWarnIdIfExported :: Bag OccName -> NameSet -> Id -> TcM ()
topSigWarnIdIfExported exported sig_ns id
  | getOccName id `elemBag` exported
  = topSigWarnId sig_ns id
  | otherwise
  = return ()

401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426
topSigWarn :: NameSet -> SigWarn
topSigWarn sig_ns _ ids = mapM_ (topSigWarnId sig_ns) ids

topSigWarnId :: NameSet -> Id -> TcM ()
-- The NameSet is the Ids that *lack* a signature
-- We have to do it this way round because there are
-- lots of top-level bindings that are generated by GHC
-- and that don't have signatures
topSigWarnId sig_ns id
  | idName id `elemNameSet` sig_ns = warnMissingSig msg id
  | otherwise                      = return ()
  where
    msg = ptext (sLit "Top-level binding with no type signature:")

localSigWarn :: NameSet -> SigWarn
localSigWarn sig_ns is_abs_bind ids
  | not is_abs_bind = return ()
  | otherwise       = mapM_ (localSigWarnId sig_ns) ids

localSigWarnId :: NameSet -> Id -> TcM ()
-- NameSet are the Ids that *have* type signatures
localSigWarnId sig_ns id
  | not (isSigmaTy (idType id))    = return ()
  | idName id `elemNameSet` sig_ns = return ()
  | otherwise                      = warnMissingSig msg id
  where
Gabor Greif's avatar
Gabor Greif committed
427
    msg = ptext (sLit "Polymorphic local binding with no type signature:")
428 429 430 431 432 433 434

warnMissingSig :: SDoc -> Id -> TcM ()
warnMissingSig msg id
  = do  { env0 <- tcInitTidyEnv
        ; let (env1, tidy_ty) = tidyOpenType env0 (idType id)
        ; addWarnTcM (env1, mk_msg tidy_ty) }
  where
435
    mk_msg ty = sep [ msg, nest 2 $ pprPrefixName (idName id) <+> dcolon <+> ppr ty ]
436 437 438

---------------------------------------------
zonkMonoBinds :: ZonkEnv -> SigWarn -> LHsBinds TcId -> TcM (LHsBinds Id)
cactus's avatar
cactus committed
439 440
zonkMonoBinds env sig_warn binds = mapBagM (zonk_lbind env sig_warn) binds

441 442
zonk_lbind :: ZonkEnv -> SigWarn -> LHsBind TcId -> TcM (LHsBind Id)
zonk_lbind env sig_warn = wrapLocM (zonk_bind env sig_warn)
443

444 445
zonk_bind :: ZonkEnv -> SigWarn -> HsBind TcId -> TcM (HsBind Id)
zonk_bind env sig_warn bind@(PatBind { pat_lhs = pat, pat_rhs = grhss, pat_rhs_ty = ty})
446
  = do  { (_env, new_pat) <- zonkPat env pat            -- Env already extended
447
        ; sig_warn False (collectPatBinders new_pat)
448 449 450
        ; new_grhss <- zonkGRHSs env zonkLExpr grhss
        ; new_ty    <- zonkTcTypeToType env ty
        ; return (bind { pat_lhs = new_pat, pat_rhs = new_grhss, pat_rhs_ty = new_ty }) }
451

452 453 454 455 456 457 458 459 460 461 462
zonk_bind env sig_warn (VarBind { var_id = var, var_rhs = expr, var_inline = inl })
  = do { new_var  <- zonkIdBndr env var
       ; sig_warn False [new_var]
       ; new_expr <- zonkLExpr env expr
       ; return (VarBind { var_id = new_var, var_rhs = new_expr, var_inline = inl }) }

zonk_bind env sig_warn bind@(FunBind { fun_id = L loc var, fun_matches = ms
                                     , fun_co_fn = co_fn })
  = do { new_var <- zonkIdBndr env var
       ; sig_warn False [new_var]
       ; (env1, new_co_fn) <- zonkCoFn env co_fn
463
       ; new_ms <- zonkMatchGroup env1 zonkLExpr ms
464 465 466 467 468
       ; return (bind { fun_id = L loc new_var, fun_matches = new_ms
                      , fun_co_fn = new_co_fn }) }

zonk_bind env sig_warn (AbsBinds { abs_tvs = tyvars, abs_ev_vars = evs
                                 , abs_ev_binds = ev_binds
469
                                 , abs_exports = exports
470
                                 , abs_binds = val_binds })
471
  = ASSERT( all isImmutableTyVar tyvars )
dreixel's avatar
dreixel committed
472 473
    do { (env0, new_tyvars) <- zonkTyBndrsX env tyvars
       ; (env1, new_evs) <- zonkEvBndrsX env0 evs
474
       ; (env2, new_ev_binds) <- zonkTcEvBinds_s env1 ev_binds
475
       ; (new_val_bind, new_exports) <- fixM $ \ ~(new_val_binds, _) ->
dreixel's avatar
dreixel committed
476
         do { let env3 = extendIdZonkEnv env2 (collectHsBindsBinders new_val_binds)
477 478 479
            ; new_val_binds <- zonkMonoBinds env3 noSigWarn val_binds
            ; new_exports   <- mapM (zonkExport env3) exports
            ; return (new_val_binds, new_exports) }
480
       ; sig_warn True (map abe_poly new_exports)
dreixel's avatar
dreixel committed
481 482
       ; return (AbsBinds { abs_tvs = new_tyvars, abs_ev_vars = new_evs
                          , abs_ev_binds = new_ev_binds
483
                          , abs_exports = new_exports, abs_binds = new_val_bind }) }
sof's avatar
sof committed
484
  where
485 486
    zonkExport env (ABE{ abe_wrap = wrap, abe_poly = poly_id
                       , abe_mono = mono_id, abe_prags = prags })
ian@well-typed.com's avatar
ian@well-typed.com committed
487 488 489 490 491 492
        = do new_poly_id <- zonkIdBndr env poly_id
             (_, new_wrap) <- zonkCoFn env wrap
             new_prags <- zonkSpecPrags env prags
             return (ABE{ abe_wrap = new_wrap, abe_poly = new_poly_id
                        , abe_mono = zonkIdOcc env mono_id
                        , abe_prags = new_prags })
493

494 495 496 497
zonk_bind env _sig_warn (PatSynBind bind@(PSB { psb_id = L loc id
                                              , psb_args = details
                                              , psb_def = lpat
                                              , psb_dir = dir }))
cactus's avatar
cactus committed
498 499 500 501
  = do { id' <- zonkIdBndr env id
       ; details' <- zonkPatSynDetails env details
       ;(env1, lpat') <- zonkPat env lpat
       ; (_env2, dir') <- zonkPatSynDir env1 dir
502 503 504 505 506
       ; return $ PatSynBind $
                  bind { psb_id = L loc id'
                       , psb_args = details'
                       , psb_def = lpat'
                       , psb_dir = dir' } }
cactus's avatar
cactus committed
507 508 509 510 511 512 513 514 515

zonkPatSynDetails :: ZonkEnv
                  -> HsPatSynDetails (Located TcId)
                  -> TcM (HsPatSynDetails (Located Id))
zonkPatSynDetails env = traverse (wrapLocM $ zonkIdBndr env)

zonkPatSynDir :: ZonkEnv -> HsPatSynDir TcId -> TcM (ZonkEnv, HsPatSynDir Id)
zonkPatSynDir env Unidirectional = return (env, Unidirectional)
zonkPatSynDir env ImplicitBidirectional = return (env, ImplicitBidirectional)
516 517 518
zonkPatSynDir env (ExplicitBidirectional mg) = do
    mg' <- zonkMatchGroup env zonkLExpr mg
    return (env, ExplicitBidirectional mg')
cactus's avatar
cactus committed
519

520 521
zonkSpecPrags :: ZonkEnv -> TcSpecPrags -> TcM TcSpecPrags
zonkSpecPrags _   IsDefaultMethod = return IsDefaultMethod
522
zonkSpecPrags env (SpecPrags ps)  = do { ps' <- zonkLTcSpecPrags env ps
523
                                       ; return (SpecPrags ps') }
524 525 526 527

zonkLTcSpecPrags :: ZonkEnv -> [LTcSpecPrag] -> TcM [LTcSpecPrag]
zonkLTcSpecPrags env ps
  = mapM zonk_prag ps
528
  where
529
    zonk_prag (L loc (SpecPrag id co_fn inl))
530 531
        = do { (_, co_fn') <- zonkCoFn env co_fn
             ; return (L loc (SpecPrag (zonkIdOcc env id) co_fn' inl)) }
532

Austin Seipp's avatar
Austin Seipp committed
533 534 535
{-
************************************************************************
*                                                                      *
536
\subsection[BackSubst-Match-GRHSs]{Match and GRHSs}
Austin Seipp's avatar
Austin Seipp committed
537 538 539
*                                                                      *
************************************************************************
-}
540

541
zonkMatchGroup :: ZonkEnv
542 543
               -> (ZonkEnv -> Located (body TcId) -> TcM (Located (body Id)))
               -> MatchGroup TcId (Located (body TcId)) -> TcM (MatchGroup Id (Located (body Id)))
544
zonkMatchGroup env zBody (MG { mg_alts = ms, mg_arg_tys = arg_tys, mg_res_ty = res_ty, mg_origin = origin })
545 546 547
  = do  { ms' <- mapM (zonkMatch env zBody) ms
        ; arg_tys' <- zonkTcTypeToTypes env arg_tys
        ; res_ty'  <- zonkTcTypeToType env res_ty
548
        ; return (MG { mg_alts = ms', mg_arg_tys = arg_tys', mg_res_ty = res_ty', mg_origin = origin }) }
549

550
zonkMatch :: ZonkEnv
551 552
          -> (ZonkEnv -> Located (body TcId) -> TcM (Located (body Id)))
          -> LMatch TcId (Located (body TcId)) -> TcM (LMatch Id (Located (body Id)))
Alan Zimmerman's avatar
Alan Zimmerman committed
553
zonkMatch env zBody (L loc (Match mf pats _ grhss))
554 555
  = do  { (env1, new_pats) <- zonkPats env pats
        ; new_grhss <- zonkGRHSs env1 zBody grhss
Alan Zimmerman's avatar
Alan Zimmerman committed
556
        ; return (L loc (Match mf new_pats Nothing new_grhss)) }
557

558
-------------------------------------------------------------------------
559
zonkGRHSs :: ZonkEnv
560 561
          -> (ZonkEnv -> Located (body TcId) -> TcM (Located (body Id)))
          -> GRHSs TcId (Located (body TcId)) -> TcM (GRHSs Id (Located (body Id)))
562

563
zonkGRHSs env zBody (GRHSs grhss binds) = do
ian@well-typed.com's avatar
ian@well-typed.com committed
564
    (new_env, new_binds) <- zonkLocalBinds env binds
565
    let
566
        zonk_grhs (GRHS guarded rhs)
ian@well-typed.com's avatar
ian@well-typed.com committed
567 568 569 570
          = do (env2, new_guarded) <- zonkStmts new_env zonkLExpr guarded
               new_rhs <- zBody env2 rhs
               return (GRHS new_guarded new_rhs)
    new_grhss <- mapM (wrapLocM zonk_grhs) grhss
571
    return (GRHSs new_grhss new_binds)
572

Austin Seipp's avatar
Austin Seipp committed
573 574 575
{-
************************************************************************
*                                                                      *
576
\subsection[BackSubst-HsExpr]{Running a zonkitution over a TypeCheckedExpr}
Austin Seipp's avatar
Austin Seipp committed
577 578 579
*                                                                      *
************************************************************************
-}
580

581 582 583
zonkLExprs :: ZonkEnv -> [LHsExpr TcId] -> TcM [LHsExpr Id]
zonkLExpr  :: ZonkEnv -> LHsExpr TcId   -> TcM (LHsExpr Id)
zonkExpr   :: ZonkEnv -> HsExpr TcId    -> TcM (HsExpr Id)
584

585
zonkLExprs env exprs = mapM (zonkLExpr env) exprs
586
zonkLExpr  env expr  = wrapLocM (zonkExpr env) expr
587

588
zonkExpr env (HsVar id)
589
  = return (HsVar (zonkIdOcc env id))
590

591
zonkExpr _ (HsIPVar id)
592
  = return (HsIPVar id)
593

594
zonkExpr env (HsLit (HsRat f ty))
ian@well-typed.com's avatar
ian@well-typed.com committed
595 596
  = do new_ty <- zonkTcTypeToType env ty
       return (HsLit (HsRat f new_ty))
sof's avatar
sof committed
597

Ian Lynagh's avatar
Ian Lynagh committed
598
zonkExpr _ (HsLit lit)
599
  = return (HsLit lit)
600 601

zonkExpr env (HsOverLit lit)
602 603
  = do  { lit' <- zonkOverLit env lit
        ; return (HsOverLit lit') }
604

605
zonkExpr env (HsLam matches)
ian@well-typed.com's avatar
ian@well-typed.com committed
606 607
  = do new_matches <- zonkMatchGroup env zonkLExpr matches
       return (HsLam new_matches)
608

609
zonkExpr env (HsLamCase arg matches)
ian@well-typed.com's avatar
ian@well-typed.com committed
610 611 612
  = do new_arg <- zonkTcTypeToType env arg
       new_matches <- zonkMatchGroup env zonkLExpr matches
       return (HsLamCase new_arg new_matches)
613

614
zonkExpr env (HsApp e1 e2)
ian@well-typed.com's avatar
ian@well-typed.com committed
615 616 617
  = do new_e1 <- zonkLExpr env e1
       new_e2 <- zonkLExpr env e2
       return (HsApp new_e1 new_e2)
618

gmainland's avatar
gmainland committed
619 620 621
zonkExpr _ e@(HsRnBracketOut _ _)
  = pprPanic "zonkExpr: HsRnBracketOut" (ppr e)

622
zonkExpr env (HsTcBracketOut body bs)
ian@well-typed.com's avatar
ian@well-typed.com committed
623
  = do bs' <- mapM zonk_b bs
624
       return (HsTcBracketOut body bs')
625
  where
626 627
    zonk_b (PendingTcSplice n e) = do e' <- zonkLExpr env e
                                      return (PendingTcSplice n e')
gmainland's avatar
gmainland committed
628

629 630
zonkExpr _ (HsSpliceE s) = WARN( True, ppr s ) -- Should not happen
                           return (HsSpliceE s)
631 632

zonkExpr env (OpApp e1 op fixity e2)
ian@well-typed.com's avatar
ian@well-typed.com committed
633 634 635 636
  = do new_e1 <- zonkLExpr env e1
       new_op <- zonkLExpr env op
       new_e2 <- zonkLExpr env e2
       return (OpApp new_e1 new_op fixity new_e2)
637

638
zonkExpr env (NegApp expr op)
ian@well-typed.com's avatar
ian@well-typed.com committed
639 640 641
  = do new_expr <- zonkLExpr env expr
       new_op <- zonkExpr env op
       return (NegApp new_expr new_op)
642

643
zonkExpr env (HsPar e)
ian@well-typed.com's avatar
ian@well-typed.com committed
644 645
  = do new_e <- zonkLExpr env e
       return (HsPar new_e)
646 647

zonkExpr env (SectionL expr op)
ian@well-typed.com's avatar
ian@well-typed.com committed
648 649 650
  = do new_expr <- zonkLExpr env expr
       new_op   <- zonkLExpr env op
       return (SectionL new_expr new_op)
651 652

zonkExpr env (SectionR op expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
653 654 655
  = do new_op   <- zonkLExpr env op
       new_expr <- zonkLExpr env expr
       return (SectionR new_op new_expr)
656

657 658 659 660
zonkExpr env (ExplicitTuple tup_args boxed)
  = do { new_tup_args <- mapM zonk_tup_arg tup_args
       ; return (ExplicitTuple new_tup_args boxed) }
  where
661 662 663 664
    zonk_tup_arg (L l (Present e)) = do { e' <- zonkLExpr env e
                                        ; return (L l (Present e')) }
    zonk_tup_arg (L l (Missing t)) = do { t' <- zonkTcTypeToType env t
                                        ; return (L l (Missing t')) }
665

666
zonkExpr env (HsCase expr ms)
ian@well-typed.com's avatar
ian@well-typed.com committed
667 668 669
  = do new_expr <- zonkLExpr env expr
       new_ms <- zonkMatchGroup env zonkLExpr ms
       return (HsCase new_expr new_ms)
670

671 672 673 674 675
zonkExpr env (HsIf e0 e1 e2 e3)
  = do { new_e0 <- fmapMaybeM (zonkExpr env) e0
       ; new_e1 <- zonkLExpr env e1
       ; new_e2 <- zonkLExpr env e2
       ; new_e3 <- zonkLExpr env e3
676
       ; return (HsIf new_e0 new_e1 new_e2 new_e3) }
677

678 679 680
zonkExpr env (HsMultiIf ty alts)
  = do { alts' <- mapM (wrapLocM zonk_alt) alts
       ; ty'   <- zonkTcTypeToType env ty
681
       ; return $ HsMultiIf ty' alts' }
682
  where zonk_alt (GRHS guard expr)
683
          = do { (env', guard') <- zonkStmts env zonkLExpr guard
684
               ; expr'          <- zonkLExpr env' expr
685
               ; return $ GRHS guard' expr' }
686

687
zonkExpr env (HsLet binds expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
688 689
  = do (new_env, new_binds) <- zonkLocalBinds env binds
       new_expr <- zonkLExpr new_env expr
690
       return (HsLet new_binds new_expr)
691

692
zonkExpr env (HsDo do_or_lc stmts ty)
ian@well-typed.com's avatar
ian@well-typed.com committed
693 694
  = do (_, new_stmts) <- zonkStmts env zonkLExpr stmts
       new_ty <- zonkTcTypeToType env ty
695
       return (HsDo do_or_lc new_stmts new_ty)
696

697
zonkExpr env (ExplicitList ty wit exprs)
ian@well-typed.com's avatar
ian@well-typed.com committed
698 699 700 701
  = do new_ty <- zonkTcTypeToType env ty
       new_wit <- zonkWit env wit
       new_exprs <- zonkLExprs env exprs
       return (ExplicitList new_ty new_wit new_exprs)
702
   where zonkWit _ Nothing = return Nothing
ian@well-typed.com's avatar
ian@well-typed.com committed
703 704
         zonkWit env (Just fln) = do new_fln <- zonkExpr env fln
                                     return (Just new_fln)
705 706

zonkExpr env (ExplicitPArr ty exprs)
ian@well-typed.com's avatar
ian@well-typed.com committed
707 708 709
  = do new_ty <- zonkTcTypeToType env ty
       new_exprs <- zonkLExprs env exprs
       return (ExplicitPArr new_ty new_exprs)
710

711
zonkExpr env (RecordCon data_con con_expr rbinds)
712 713 714
  = do  { new_con_expr <- zonkExpr env con_expr
        ; new_rbinds   <- zonkRecFields env rbinds
        ; return (RecordCon data_con new_con_expr new_rbinds) }
715

716
zonkExpr env (RecordUpd expr rbinds cons in_tys out_tys)
717 718 719
  = do  { new_expr    <- zonkLExpr env expr
        ; new_in_tys  <- mapM (zonkTcTypeToType env) in_tys
        ; new_out_tys <- mapM (zonkTcTypeToType env) out_tys
720
        ; new_rbinds  <- zonkRecUpdFields env rbinds
721
        ; return (RecordUpd new_expr new_rbinds cons new_in_tys new_out_tys) }
722

723
zonkExpr env (ExprWithTySigOut e ty)
724 725 726
  = do { e' <- zonkLExpr env e
       ; return (ExprWithTySigOut e' ty) }

thomasw's avatar
thomasw committed
727
zonkExpr _ (ExprWithTySig _ _ _) = panic "zonkExpr env:ExprWithTySig"
728

729
zonkExpr env (ArithSeq expr wit info)
ian@well-typed.com's avatar
ian@well-typed.com committed
730 731 732 733
  = do new_expr <- zonkExpr env expr
       new_wit <- zonkWit env wit
       new_info <- zonkArithSeq env info
       return (ArithSeq new_expr new_wit new_info)
734
   where zonkWit _ Nothing = return Nothing
ian@well-typed.com's avatar
ian@well-typed.com committed
735 736
         zonkWit env (Just fln) = do new_fln <- zonkExpr env fln
                                     return (Just new_fln)
737

738
zonkExpr env (PArrSeq expr info)
ian@well-typed.com's avatar
ian@well-typed.com committed
739 740 741
  = do new_expr <- zonkExpr env expr
       new_info <- zonkArithSeq env info
       return (PArrSeq new_expr new_info)
742

Alan Zimmerman's avatar
Alan Zimmerman committed
743
zonkExpr env (HsSCC src lbl expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
744
  = do new_expr <- zonkLExpr env expr
Alan Zimmerman's avatar
Alan Zimmerman committed
745
       return (HsSCC src lbl new_expr)
746

Alan Zimmerman's avatar
Alan Zimmerman committed
747
zonkExpr env (HsTickPragma src info expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
748
  = do new_expr <- zonkLExpr env expr
Alan Zimmerman's avatar
Alan Zimmerman committed
749
       return (HsTickPragma src info new_expr)
andy@galois.com's avatar
andy@galois.com committed
750

751
-- hdaume: core annotations
Alan Zimmerman's avatar
Alan Zimmerman committed
752
zonkExpr env (HsCoreAnn src lbl expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
753
  = do new_expr <- zonkLExpr env expr
Alan Zimmerman's avatar
Alan Zimmerman committed
754
       return (HsCoreAnn src lbl new_expr)
755

756
-- arrow notation extensions
757
zonkExpr env (HsProc pat body)
758 759 760
  = do  { (env1, new_pat) <- zonkPat env pat
        ; new_body <- zonkCmdTop env1 body
        ; return (HsProc new_pat new_body) }
761

762 763 764 765
-- StaticPointers extension
zonkExpr env (HsStatic expr)
  = HsStatic <$> zonkLExpr env expr

766
zonkExpr env (HsWrap co_fn expr)
ian@well-typed.com's avatar
ian@well-typed.com committed
767 768 769
  = do (env1, new_co_fn) <- zonkCoFn env co_fn
       new_expr <- zonkExpr env1 expr
       return (HsWrap new_co_fn new_expr)
770

771 772
zonkExpr _ (HsUnboundVar v)
  = return (HsUnboundVar v)
773

Ian Lynagh's avatar
Ian Lynagh committed
774
zonkExpr _ expr = pprPanic "zonkExpr" (ppr expr)
775

776 777 778 779 780 781 782
-------------------------------------------------------------------------

zonkLCmd  :: ZonkEnv -> LHsCmd TcId   -> TcM (LHsCmd Id)
zonkCmd   :: ZonkEnv -> HsCmd TcId    -> TcM (HsCmd Id)

zonkLCmd  env cmd  = wrapLocM (zonkCmd env) cmd

783
zonkCmd env (HsCmdCast co cmd)
Joachim Breitner's avatar
Joachim Breitner committed
784
  = do { co' <- zonkTcCoToCo env co
785
       ; cmd' <- zonkCmd env cmd
786
       ; return (HsCmdCast co' cmd') }
787
zonkCmd env (HsCmdArrApp e1 e2 ty ho rl)
ian@well-typed.com's avatar
ian@well-typed.com committed
788 789 790 791
  = do new_e1 <- zonkLExpr env e1
       new_e2 <- zonkLExpr env e2
       new_ty <- zonkTcTypeToType env ty
       return (HsCmdArrApp new_e1 new_e2 new_ty ho rl)
792 793

zonkCmd env (HsCmdArrForm op fixity args)
ian@well-typed.com's avatar
ian@well-typed.com committed
794 795 796
  = do new_op <- zonkLExpr env op
       new_args <- mapM (zonkCmdTop env) args
       return (HsCmdArrForm new_op fixity new_args)
797 798

zonkCmd env (HsCmdApp c e)
ian@well-typed.com's avatar
ian@well-typed.com committed
799 800 801
  = do new_c <- zonkLCmd env c
       new_e <- zonkLExpr env e
       return (HsCmdApp new_c new_e)
802 803

zonkCmd env (HsCmdLam matches)
ian@well-typed.com's avatar
ian@well-typed.com committed
804 805
  = do new_matches <- zonkMatchGroup env zonkLCmd matches
       return (HsCmdLam new_matches)
806

807
zonkCmd env (HsCmdPar c)
ian@well-typed.com's avatar
ian@well-typed.com committed
808 809
  = do new_c <- zonkLCmd env c
       return (HsCmdPar new_c)
810 811

zonkCmd env (HsCmdCase expr ms)
ian@well-typed.com's avatar
ian@well-typed.com committed
812 813 814
  = do new_expr <- zonkLExpr env expr
       new_ms <- zonkMatchGroup env zonkLCmd ms
       return (HsCmdCase new_expr new_ms)
815 816 817 818 819 820

zonkCmd env (HsCmdIf eCond ePred cThen cElse)
  = do { new_eCond <- fmapMaybeM (zonkExpr env) eCond
       ; new_ePred <- zonkLExpr env ePred
       ; new_cThen <- zonkLCmd env cThen
       ; new_cElse <- zonkLCmd env cElse
821
       ; return (HsCmdIf new_eCond new_ePred new_cThen new_cElse) }
822

823
zonkCmd env (HsCmdLet binds cmd)
ian@well-typed.com's avatar
ian@well-typed.com committed
824 825
  = do (new_env, new_binds) <- zonkLocalBinds env binds
       new_cmd <- zonkLCmd new_env cmd
826
       return (HsCmdLet new_binds new_cmd)
827

828
zonkCmd env (HsCmdDo stmts ty)
ian@well-typed.com's avatar
ian@well-typed.com committed
829 830
  = do (_, new_stmts) <- zonkStmts env zonkLCmd stmts
       new_ty <- zonkTcTypeToType env ty
831
       return (HsCmdDo new_stmts new_ty)
832 833 834 835 836





837 838 839
zonkCmdTop :: ZonkEnv -> LHsCmdTop TcId -> TcM (LHsCmdTop Id)
zonkCmdTop env cmd = wrapLocM (zonk_cmd_top env) cmd

Ian Lynagh's avatar
Ian Lynagh committed
840
zonk_cmd_top :: ZonkEnv -> HsCmdTop TcId -> TcM (HsCmdTop Id)
841
zonk_cmd_top env (HsCmdTop cmd stack_tys ty ids)
ian@well-typed.com's avatar
ian@well-typed.com committed
842 843 844 845 846
  = do new_cmd <- zonkLCmd env cmd
       new_stack_tys <- zonkTcTypeToType env stack_tys
       new_ty <- zonkTcTypeToType env ty
       new_ids <- mapSndM (zonkExpr env) ids
       return (HsCmdTop new_cmd new_stack_tys new_ty new_ids)
847

848
-------------------------------------------------------------------------
849
zonkCoFn :: ZonkEnv -> HsWrapper -> TcM (ZonkEnv, HsWrapper)
850
zonkCoFn env WpHole   = return (env, WpHole)
851
zonkCoFn env (WpCompose c1 c2) = do { (env1, c1') <- zonkCoFn env c1
852 853
                                    ; (env2, c2') <- zonkCoFn env1 c2
                                    ; return (env2, WpCompose c1' c2') }
854 855 856 857 858
zonkCoFn env (WpFun c1 c2 t1 t2) = do { (env1, c1') <- zonkCoFn env c1
                                      ; (env2, c2') <- zonkCoFn env1 c2
                                      ; t1'         <- zonkTcTypeToType env2 t1
                                      ; t2'         <- zonkTcTypeToType env2 t2
                                      ; return (env2, WpFun c1' c2' t1' t2') }
Joachim Breitner's avatar
Joachim Breitner committed
859
zonkCoFn env (WpCast co) = do { co' <- zonkTcCoToCo env co
860
                              ; return (env, WpCast co') }
861
zonkCoFn env (WpEvLam ev)   = do { (env', ev') <- zonkEvBndrX env ev
862 863
                                 ; return (env', WpEvLam ev') }
zonkCoFn env (WpEvApp arg)  = do { arg' <- zonkEvTerm env arg
864
                                 ; return (env, WpEvApp arg') }
865
zonkCoFn env (WpTyLam tv)   = ASSERT( isImmutableTyVar tv )
dreixel's avatar
dreixel committed
866
                              do { (env', tv') <- zonkTyBndrX env tv
867
                                 ; return (env', WpTyLam tv') }
868
zonkCoFn env (WpTyApp ty)   = do { ty' <- zonkTcTypeToType env ty
869
                                 ; return (env, WpTyApp ty') }
870
zonkCoFn env (WpLet bs)     = do { (env1, bs') <- zonkTcEvBinds env bs
871
                                 ; return (env1, WpLet bs') }
872

873 874
-------------------------------------------------------------------------
zonkOverLit :: ZonkEnv -> HsOverLit TcId -> TcM (HsOverLit Id)
875
zonkOverLit env lit@(OverLit { ol_witness = e, ol_type = ty })
876 877 878
  = do  { ty' <- zonkTcTypeToType env ty
        ; e' <- zonkExpr env e
        ; return (lit { ol_witness = e', ol_type = ty' }) }
879

880
-------------------------------------------------------------------------
881
zonkArithSeq :: ZonkEnv -> ArithSeqInfo TcId -> TcM (ArithSeqInfo Id)
882

883
zonkArithSeq env (From e)
ian@well-typed.com's avatar
ian@well-typed.com committed
884 885
  = do new_e <- zonkLExpr env e
       return (From new_e)
886