module TcModule (
typecheckModule,
- TcResults(..),
- TcResultBinds(..),
- TcIfaceInfo(..),
- TcLocalTyConsAndClasses(..),
- TcSpecialiseRequests(..),
- TcDDumpDeriv(..)
+ SYN_IE(TcResults),
+ SYN_IE(TcResultBinds),
+ SYN_IE(TcSpecialiseRequests),
+ SYN_IE(TcDDumpDeriv)
) where
-import Ubiq{-uitous-}
+IMP_Ubiq(){-uitous-}
-import HsSyn ( HsModule(..), HsBinds(..), Bind, HsExpr,
- TyDecl, SpecDataSig, ClassDecl, InstDecl,
+import HsSyn ( HsDecl(..), HsModule(..), HsBinds(..), Bind, HsExpr,
+ TyDecl, SpecDataSig, ClassDecl, InstDecl, IfaceSig,
SpecInstSig, DefaultDecl, Sig, Fake, InPat,
FixityDecl, IE, ImportDecl
)
-import RnHsSyn ( RenamedHsModule(..), RenamedFixityDecl(..) )
-import TcHsSyn ( TypecheckedHsBinds(..), TypecheckedHsExpr(..),
+import RnHsSyn ( SYN_IE(RenamedHsModule), RenamedFixityDecl(..) )
+import TcHsSyn ( SYN_IE(TypecheckedHsBinds), SYN_IE(TypecheckedHsExpr),
TcIdOcc(..), zonkBinds, zonkDictBinds )
-import TcMonad hiding ( rnMtoTcM )
+import TcMonad
import Inst ( Inst, plusLIE )
import TcBinds ( tcBindsAndThen )
import TcClassDcl ( tcClassDecls2 )
import TcDefaults ( tcDefaults )
import TcEnv ( tcExtendGlobalValEnv, getEnv_LocalIds,
- getEnv_TyCons, getEnv_Classes,
- tcLookupLocalValueByKey, tcLookupTyConByKey )
+ getEnv_TyCons, getEnv_Classes, tcLookupLocalValue,
+ tcLookupLocalValueByKey, tcLookupTyCon,
+ tcLookupGlobalValueByKeyMaybe )
+import SpecEnv ( SpecEnv )
+import TcExpr ( tcId )
import TcIfaceSig ( tcInterfaceSigs )
import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
import TcInstUtil ( buildInstanceEnvs, InstInfo )
import TcSimplify ( tcSimplifyTop )
import TcTyClsDecls ( tcTyAndClassDecls1 )
import TcTyDecls ( mkDataBinds )
+import TcType ( SYN_IE(TcType), tcInstType )
+import TcKind ( TcKind )
+import RnMonad ( RnNameSupply(..) )
import Bag ( listToBag )
import Class ( GenClass, classSelIds )
-import ErrUtils ( Warning(..), Error(..) )
-import Id ( GenId, isDataCon, isMethodSelId, idType, IdEnv(..), nullIdEnv )
+import ErrUtils ( SYN_IE(Warning), SYN_IE(Error) )
+import Id ( idType, GenId, SYN_IE(IdEnv), nullIdEnv )
import Maybes ( catMaybes )
-import Name ( isExported, isLocallyDefined )
+import Name ( Name, isLocallyDefined, pprModule )
import Pretty
-import RnUtils ( RnEnv(..) )
-import TyCon ( isDataTyCon, TyCon )
-import Type ( mkSynTy )
-import TysWiredIn ( unitTy, mkPrimIoTy )
-import TyVar ( TyVarEnv(..), nullTyVarEnv )
+import TyCon ( TyCon, isSynTyCon )
+import Type ( applyTyCon, mkSynTy )
+import PprType ( GenType, GenTyVar )
+import TysWiredIn ( unitTy )
+import PrelMods ( gHC_MAIN, mAIN )
+import PrelInfo ( main_NAME, mainPrimIO_NAME, ioTyCon_NAME, primIoTyCon_NAME )
+import TyVar ( GenTyVar, SYN_IE(TyVarEnv), nullTyVarEnv )
import Unify ( unifyTauTy )
import UniqFM ( lookupUFM_Directly, lookupWithDefaultUFM_Directly,
filterUFM, eltsUFM )
-import Unique ( iOTyConKey, mainIdKey, mainPrimIOIdKey )
+import Unique ( Unique )
import Util
+import Bag ( Bag, isEmptyBag )
-import FiniteMap ( emptyFM )
+import FiniteMap ( emptyFM, FiniteMap )
tycon_specs = emptyFM
\end{code}
-- Convenient type synonyms first:
type TcResults
= (TcResultBinds,
- TcIfaceInfo,
- TcLocalTyConsAndClasses,
+ [TyCon],
+ Bag InstInfo, -- Instance declaration information
TcSpecialiseRequests,
TcDDumpDeriv)
[(Id, TypecheckedHsExpr)]) -- constant instance binds
-type TcIfaceInfo -- things for the interface generator
- = ([Id], [TyCon], [Class], Bag InstInfo)
-
-type TcLocalTyConsAndClasses -- things defined in this module
- = ([TyCon], [Class])
- -- not sure the classes are used at all (ToDo)
-
type TcSpecialiseRequests
= FiniteMap TyCon [(Bool, [Maybe Type])]
-- source tycon specialisation requests
---------------
typecheckModule
:: UniqSupply
- -> RnEnv -- for renaming derivings
+ -> RnNameSupply
-> RenamedHsModule
-> MaybeErr
(TcResults, -- if all goes well...
(Bag Error, -- if we had errors...
Bag Warning)
-typecheckModule us rn_env mod
- = initTc us (tcModule rn_env mod)
+typecheckModule us rn_name_supply mod
+ = initTc us (tcModule rn_name_supply mod)
\end{code}
The internal monster:
\begin{code}
-tcModule :: RnEnv -- for renaming derivings
+tcModule :: RnNameSupply -- for renaming derivings
-> RenamedHsModule -- input
-> TcM s TcResults -- output
-tcModule rn_env
- (HsModule mod_name verion exports imports fixities
- ty_decls specdata_sigs cls_decls inst_decls specinst_sigs
- default_decls val_decls sigs src_loc)
-
- = ASSERT(null imports)
-
- tcAddSrcLoc src_loc $ -- record where we're starting
+tcModule rn_name_supply
+ (HsModule mod_name verion exports imports fixities decls src_loc)
+ = tcAddSrcLoc src_loc $ -- record where we're starting
-- Tie the knot for inteface-file value declaration signatures
-- This info is only used inside the knot for type-checking the
-- pragmas, which is done lazily [ie failure just drops the pragma
-- without having any global-failure effect].
+ -- trace "tc1" $
+
fixTc (\ ~(_, _, _, _, _, _, sig_ids) ->
+
+ -- trace "tc2" $
tcExtendGlobalValEnv sig_ids (
-- The knot for instance information. This isn't used at all
fixTc ( \ ~(rec_inst_mapper, _, _, _, _) ->
-- Type-check the type and class decls
- --trace "tcTyAndClassDecls:" $
- tcTyAndClassDecls1 rec_inst_mapper ty_decls_bag cls_decls_bag
- `thenTc` \ env ->
+ -- trace "tcTyAndClassDecls:" $
+ tcTyAndClassDecls1 rec_inst_mapper decls `thenTc` \ env ->
+ -- trace "tc3" $
-- Typecheck the instance decls, includes deriving
tcSetEnv env (
- --trace "tcInstDecls:" $
- tcInstDecls1 inst_decls_bag specinst_sigs
- mod_name rn_env fixities
- ) `thenTc` \ (inst_info, deriv_binds, ddump_deriv) ->
+ -- trace "tcInstDecls:" $
+ tcInstDecls1 decls mod_name rn_name_supply
+ ) `thenTc` \ (inst_info, deriv_binds, ddump_deriv) ->
+ -- trace "tc4" $
buildInstanceEnvs inst_info `thenTc` \ inst_mapper ->
returnTc (inst_mapper, env, inst_info, deriv_binds, ddump_deriv)
) `thenTc` \ (_, env, inst_info, deriv_binds, ddump_deriv) ->
+
+ -- trace "tc5" $
tcSetEnv env (
-- Default declarations
- tcDefaults default_decls `thenTc` \ defaulting_tys ->
+ tcDefaults decls `thenTc` \ defaulting_tys ->
tcSetDefaultTys defaulting_tys ( -- for the iface sigs...
-- Create any necessary record selector Ids and their bindings
-- What we rely on is that pragmas are typechecked lazily; if
-- any type errors are found (ie there's an inconsistency)
-- we silently discard the pragma
- tcInterfaceSigs sigs `thenTc` \ sig_ids ->
+ tcInterfaceSigs decls `thenTc` \ sig_ids ->
tcGetEnv `thenNF_Tc` \ env ->
+ -- trace "tc6" $
returnTc (env, inst_info, data_binds, deriv_binds, ddump_deriv, defaulting_tys, sig_ids)
)))) `thenTc` \ (env, inst_info, data_binds, deriv_binds, ddump_deriv, defaulting_tys, _) ->
+ -- trace "tc7" $
tcSetEnv env ( -- to the end...
tcSetDefaultTys defaulting_tys ( -- ditto
-- Value declarations next.
-- We also typecheck any extra binds that came out of the "deriving" process
- --trace "tcBinds:" $
+ -- trace "tcBinds:" $
tcBindsAndThen
(\ binds1 (binds2, thing) -> (binds1 `ThenBinds` binds2, thing))
- (val_decls `ThenBinds` deriv_binds)
+ (get_val_decls decls `ThenBinds` deriv_binds)
( -- Second pass over instance declarations,
-- to compile the bindings themselves.
+ -- trace "tc8" $
tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) ->
- tcClassDecls2 cls_decls_bag `thenNF_Tc` \ (lie_clasdecls, cls_binds) ->
+ tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_binds) ->
+ tcCheckMainSig mod_name `thenTc_`
tcGetEnv `thenNF_Tc` \ env ->
returnTc ( (EmptyBinds, (inst_binds, cls_binds, env)),
lie_instdecls `plusLIE` lie_clasdecls,
`thenTc` \ ((val_binds, (inst_binds, cls_binds, final_env)), lie_alldecls, _) ->
- checkTopLevelIds mod_name final_env `thenTc_`
-
-- Deal with constant or ambiguous InstIds. How could
-- there be ambiguous ones? They can only arise if a
-- top-level decl falls under the monomorphism
-- restriction, and no subsequent decl instantiates its
-- type. (Usually, ambiguous type variables are resolved
-- during the generalisation step.)
+ -- trace "tc9" $
tcSimplifyTop lie_alldecls `thenTc` \ const_insts ->
+
-- Backsubstitution. Monomorphic top-level decls may have
-- been instantiated by subsequent decls, and the final
-- simplification step may have instantiated some
let
localids = getEnv_LocalIds final_env
- tycons = getEnv_TyCons final_env
- classes = getEnv_Classes final_env
+ tycons = getEnv_TyCons final_env
+ classes = getEnv_Classes final_env
- local_tycons = [ tc | tc <- tycons, isLocallyDefined tc && isDataTyCon tc ]
+ local_tycons = filter isLocallyDefined tycons
local_classes = filter isLocallyDefined classes
- exported_ids' = filter isExported (eltsUFM ve2)
- in
-
+ in
-- FINISHED AT LAST
returnTc (
(data_binds', cls_binds', inst_binds', val_binds', const_insts'),
- -- the next collection is just for mkInterface
- (exported_ids', tycons, classes, inst_info),
-
- (local_tycons, local_classes),
-
- tycon_specs,
+ local_tycons, inst_info, tycon_specs,
ddump_deriv
)))
- where
- ty_decls_bag = listToBag ty_decls
- cls_decls_bag = listToBag cls_decls
- inst_decls_bag = listToBag inst_decls
+get_val_decls decls = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls]
\end{code}
-%************************************************************************
-%* *
-\subsection{Error checking code}
-%* *
-%************************************************************************
+\begin{code}
+tcCheckMainSig mod_name
+ | not is_main && not is_ghc_main
+ = returnTc () -- A non-main module
+
+ | otherwise
+ = -- Check that main is defined
+ tcLookupTyCon tycon_name `thenTc` \ (_,_,tycon) ->
+ tcLookupLocalValue main_name `thenNF_Tc` \ maybe_main_id ->
+ case maybe_main_id of {
+ Nothing -> failTc (noMainErr mod_name main_name);
+ Just main_id ->
+
+ -- Check that it has the right type (or a more general one)
+ let
+ expected_ty | isSynTyCon tycon = mkSynTy tycon [unitTy]
+ | otherwise = applyTyCon tycon [unitTy]
+ -- This is bizarre. There ought to be a suitable function in Type.lhs!
+ in
+ tcInstType [] expected_ty `thenNF_Tc` \ expected_tau ->
+ tcId main_name `thenNF_Tc` \ (_, lie, main_tau) ->
+ tcSetErrCtxt (mainTyCheckCtxt main_name) $
+ unifyTauTy expected_tau
+ main_tau `thenTc_`
+ checkTc (isEmptyBag lie) (mainTyMisMatch main_name expected_ty (idType main_id))
+ }
+ where
+ is_main = mod_name == mAIN
+ is_ghc_main = mod_name == gHC_MAIN
+
+ main_name | is_main = main_NAME
+ | otherwise = mainPrimIO_NAME
+ tycon_name | is_main = ioTyCon_NAME
+ | otherwise = primIoTyCon_NAME
-checkTopLevelIds checks that Main.main or Main.mainPrimIO has correct type.
+mainTyCheckCtxt main_name sty
+ = ppCat [ppPStr SLIT("When checking that"), ppr sty main_name, ppPStr SLIT("has the required type")]
-\begin{code}
-checkTopLevelIds :: FAST_STRING -> TcEnv s -> TcM s ()
-checkTopLevelIds mod final_env
- | mod /= SLIT("Main")
- = returnTc ()
+noMainErr mod_name main_name sty
+ = ppCat [ppPStr SLIT("Module"), pprModule sty mod_name,
+ ppPStr SLIT("must include a definition for"), ppr sty main_name]
- | otherwise
- = tcSetEnv final_env (
- tcLookupLocalValueByKey mainIdKey `thenNF_Tc` \ maybe_main ->
- tcLookupLocalValueByKey mainPrimIOIdKey `thenNF_Tc` \ maybe_prim ->
- tcLookupTyConByKey iOTyConKey `thenNF_Tc` \ io_tc ->
-
- case (maybe_main, maybe_prim) of
- (Just main, Nothing) -> tcAddErrCtxt mainCtxt $
- unifyTauTy (mkSynTy io_tc [unitTy])
- (idType main)
-
- (Nothing, Just prim) -> tcAddErrCtxt primCtxt $
- unifyTauTy (mkPrimIoTy unitTy)
- (idType prim)
-
- (Just _ , Just _ ) -> failTc mainBothIdErr
- (Nothing, Nothing) -> failTc mainNoneIdErr
- )
-
-mainCtxt sty
- = ppStr "main should have type IO ()"
-
-primCtxt sty
- = ppStr "mainPrimIO should have type PrimIO ()"
-
-mainBothIdErr sty
- = ppStr "module Main contains definitions for both main and mainPrimIO"
-
-mainNoneIdErr sty
- = ppStr "module Main does not contain a definition for main (or mainPrimIO)"
+mainTyMisMatch :: Name -> Type -> TcType s -> Error
+mainTyMisMatch main_name expected actual sty
+ = ppHang (ppCat [ppr sty main_name, ppPStr SLIT("has the wrong type")])
+ 4 (ppAboves [
+ ppCat [ppPStr SLIT("Expected:"), ppr sty expected],
+ ppCat [ppPStr SLIT("Inferred:"), ppr sty actual]
+ ])
\end{code}