%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[TcModule]{Typechecking a whole module}
\begin{code}
-#include "HsVersions.h"
-
module TcModule (
typecheckModule,
- SYN_IE(TcResults),
- SYN_IE(TcSpecialiseRequests),
- SYN_IE(TcDDumpDeriv)
+ TcResults(..)
) where
-IMP_Ubiq(){-uitous-}
+#include "HsVersions.h"
-import CmdLineOpts ( opt_D_dump_tc, opt_D_dump_deriv )
-import HsSyn ( HsDecl(..), HsModule(..), HsBinds(..), HsExpr, MonoBinds(..),
- TyDecl, SpecDataSig, ClassDecl, InstDecl, IfaceSig,
- SpecInstSig, DefaultDecl, Sig, Fake, InPat,
- SYN_IE(RecFlag), nonRecursive, GRHSsAndBinds, Match,
- FixityDecl, IE, ImportDecl, OutPat
+import CmdLineOpts ( opt_D_dump_tc, opt_D_dump_types, opt_PprStyle_Debug )
+import HsSyn ( HsModule(..), HsBinds(..), MonoBinds(..), HsDecl(..) )
+import HsTypes ( toHsType )
+import RnHsSyn ( RenamedHsModule )
+import TcHsSyn ( TcMonoBinds, TypecheckedMonoBinds,
+ TypecheckedForeignDecl, TypecheckedRuleDecl,
+ zonkTopBinds, zonkForeignExports, zonkRules
)
-import RnHsSyn ( SYN_IE(RenamedHsModule), RenamedFixityDecl(..) )
-import TcHsSyn ( SYN_IE(TypecheckedHsBinds), SYN_IE(TypecheckedHsExpr),
- SYN_IE(TypecheckedDictBinds), SYN_IE(TcMonoBinds),
- SYN_IE(TypecheckedMonoBinds),
- zonkTopBinds )
import TcMonad
import Inst ( Inst, emptyLIE, plusLIE )
-import TcBinds ( tcBindsAndThen )
-import TcClassDcl ( tcClassDecls2 )
+import TcBinds ( tcTopBindsAndThen )
+import TcClassDcl ( tcClassDecls2, mkImplicitClassBinds )
import TcDefaults ( tcDefaults )
-import TcEnv ( tcExtendGlobalValEnv, getEnv_LocalIds,
- getEnv_TyCons, getEnv_Classes, tcLookupLocalValue,
- tcLookupLocalValueByKey, tcLookupTyCon,
- tcLookupGlobalValueByKeyMaybe )
-import SpecEnv ( SpecEnv )
-import TcExpr ( tcId )
+import TcEnv ( tcExtendGlobalValEnv, tcExtendTypeEnv,
+ getEnvTyCons, getEnvClasses, tcLookupValueByKeyMaybe,
+ tcSetValueEnv, tcSetInstEnv,
+ initEnv,
+ ValueEnv,
+ )
+import TcRules ( tcRules )
+import TcForeign ( tcForeignImports, tcForeignExports )
import TcIfaceSig ( tcInterfaceSigs )
import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
-import TcInstUtil ( buildInstanceEnvs, InstInfo )
+import TcInstUtil ( buildInstanceEnv, InstInfo )
import TcSimplify ( tcSimplifyTop )
-import TcTyClsDecls ( tcTyAndClassDecls1 )
-import TcTyDecls ( mkDataBinds )
-import TcType ( TcIdOcc(..), SYN_IE(TcType), tcInstType )
-import TcKind ( TcKind )
-
-import RnMonad ( RnNameSupply(..) )
-import Bag ( listToBag )
-import ErrUtils ( SYN_IE(Warning), SYN_IE(Error),
- pprBagOfErrors, dumpIfSet, ghcExit
+import TcTyClsDecls ( tcTyAndClassDecls )
+import TcTyDecls ( mkImplicitDataBinds )
+import TcType ( TcType, TcKind )
+
+import RnMonad ( RnNameSupply, FixityEnv )
+import Bag ( isEmptyBag )
+import ErrUtils ( Message, printErrorsAndWarnings, dumpIfSet )
+import Id ( Id, idType, idName )
+import Module ( pprModuleName, mkThisModule )
+import OccName ( isSysOcc )
+import Name ( Name, nameUnique, nameOccName, isLocallyDefined,
+ toRdrName, nameEnvElts, NamedThing(..)
)
-import Id ( idType, GenId, SYN_IE(IdEnv), nullIdEnv )
-import Maybes ( catMaybes, MaybeErr(..) )
-import Name ( Name, isLocallyDefined, pprModule )
-import Pretty
-import TyCon ( TyCon, isSynTyCon )
-import Class ( GenClass, SYN_IE(Class), classSelIds )
-import Type ( applyTyCon, mkSynTy, SYN_IE(Type) )
-import PprType ( GenType, GenTyVar )
-import TysWiredIn ( unitTy )
-import PrelMods ( gHC_MAIN, mAIN )
-import PrelInfo ( main_NAME, ioTyCon_NAME )
-import TyVar ( GenTyVar, SYN_IE(TyVarEnv), nullTyVarEnv )
-import Unify ( unifyTauTy )
-import UniqFM ( lookupUFM_Directly, lookupWithDefaultUFM_Directly,
- filterUFM, eltsUFM )
-import Unique ( Unique )
+import TyCon ( TyCon, tyConKind, tyConClass_maybe )
+import Class ( Class, classSelIds, classTyCon )
+import PrelInfo ( mAIN_Name )
+import Unique ( Unique, mainKey )
import UniqSupply ( UniqSupply )
+import Maybes ( maybeToBool )
import Util
import Bag ( Bag, isEmptyBag )
-
-import FiniteMap ( emptyFM, FiniteMap )
-
-import Outputable ( Outputable(..), PprStyle, printErrs, pprDumpStyle, pprErrorsStyle )
-
-tycon_specs = emptyFM
+import Outputable
\end{code}
Outside-world interface:
\begin{code}
---ToDo: put this in HsVersions
-#if __GLASGOW_HASKELL__ >= 200
-# define REAL_WORLD RealWorld
-#else
-# define REAL_WORLD _RealWorld
-#endif
-
-- Convenient type synonyms first:
-type TcResults
- = (TypecheckedMonoBinds,
- [TyCon], [Class],
- Bag InstInfo, -- Instance declaration information
- TcSpecialiseRequests,
- TcDDumpDeriv)
-
-type TcSpecialiseRequests
- = FiniteMap TyCon [(Bool, [Maybe Type])]
- -- source tycon specialisation requests
-
-type TcDDumpDeriv
- = PprStyle -> Doc
+data TcResults
+ = TcResults {
+ tc_binds :: TypecheckedMonoBinds,
+ tc_tycons :: [TyCon],
+ tc_classes :: [Class],
+ tc_insts :: Bag InstInfo, -- Instance declaration information
+ tc_fords :: [TypecheckedForeignDecl], -- Foreign import & exports.
+ tc_rules :: [TypecheckedRuleDecl], -- Transformation rules
+ tc_env :: ValueEnv
+ }
---------------
typecheckModule
:: UniqSupply
-> RnNameSupply
+ -> FixityEnv
-> RenamedHsModule
-> IO (Maybe TcResults)
-typecheckModule us rn_name_supply mod
- = case initTc us (tcModule rn_name_supply mod) of
- Failed (errs, warns) ->
- print_errs warns >>
- print_errs errs >>
- return Nothing
-
- Succeeded (results@(binds, _, _, _, _, dump_deriv), warns) ->
- print_errs warns >>
-
- dumpIfSet opt_D_dump_tc "Typechecked"
- (ppr pprDumpStyle binds) >>
-
- dumpIfSet opt_D_dump_deriv "Derived instances"
- (dump_deriv pprDumpStyle) >>
-
- return (Just results)
-
-print_errs errs
- | isEmptyBag errs = return ()
- | otherwise = printErrs (pprBagOfErrors pprErrorsStyle errs)
+typecheckModule us rn_name_supply fixity_env mod
+ = initTc us initEnv (tcModule rn_name_supply fixity_env mod) >>= \ (maybe_result, warns, errs) ->
+
+ printErrorsAndWarnings errs warns >>
+
+ (case maybe_result of
+ Nothing -> return ()
+ Just results -> dumpIfSet opt_D_dump_types "Type signatures" (dump_sigs results) >>
+ dumpIfSet opt_D_dump_tc "Typechecked" (dump_tc results)
+ ) >>
+
+ return (if isEmptyBag errs then
+ maybe_result
+ else
+ Nothing)
+
+dump_tc results
+ = ppr (tc_binds results) $$ pp_rules (tc_rules results)
+
+dump_sigs results -- Print type signatures
+ = -- Convert to HsType so that we get source-language style printing
+ -- And sort by RdrName
+ vcat $ map ppr_sig $ sortLt lt_sig $
+ [(toRdrName id, toHsType (idType id)) | id <- nameEnvElts (tc_env results),
+ want_sig id
+ ]
+ where
+ lt_sig (n1,_) (n2,_) = n1 < n2
+ ppr_sig (n,t) = ppr n <+> dcolon <+> ppr t
+
+ want_sig id | opt_PprStyle_Debug = True
+ | otherwise = isLocallyDefined n && not (isSysOcc (nameOccName n))
+ where
+ n = idName id
+
+pp_rules [] = empty
+pp_rules rs = vcat [ptext SLIT("{-# RULES"),
+ nest 4 (vcat (map ppr rs)),
+ ptext SLIT("#-}")]
\end{code}
The internal monster:
\begin{code}
tcModule :: RnNameSupply -- for renaming derivings
+ -> FixityEnv -- needed for Show/Read derivings.
-> RenamedHsModule -- input
-> TcM s TcResults -- output
-tcModule rn_name_supply
- (HsModule mod_name verion exports imports fixities decls src_loc)
+tcModule rn_name_supply fixities
+ (HsModule mod_name _ _ _ decls _ src_loc)
= tcAddSrcLoc src_loc $ -- record where we're starting
fixTc (\ ~(unf_env ,_) ->
-- which is done lazily [ie failure just drops the pragma
-- without having any global-failure effect].
--
- -- unf_env is also used to get the pragam info for dfuns.
+ -- unf_env is also used to get the pragam info
+ -- for imported dfuns and default methods
- -- The knot for instance information. This isn't used at all
- -- till we type-check value declarations
- fixTc ( \ ~(rec_inst_mapper, _, _, _, _) ->
-
-- Type-check the type and class decls
- -- trace "tcTyAndClassDecls:" $
- tcTyAndClassDecls1 unf_env rec_inst_mapper decls `thenTc` \ env ->
+ tcTyAndClassDecls unf_env decls `thenTc` \ env ->
- -- trace "tc3" $
- -- Typecheck the instance decls, includes deriving
- tcSetEnv env (
- -- trace "tcInstDecls:" $
- tcInstDecls1 unf_env 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)
-
- -- End of inner fix loop
- ) `thenTc` \ (_, env, inst_info, deriv_binds, ddump_deriv) ->
+ -- Typecheck the instance decls, includes deriving
+ tcSetEnv env $
+
+ tcInstDecls1 unf_env decls
+ (mkThisModule mod_name)
+ fixities rn_name_supply `thenTc` \ (inst_info, deriv_binds) ->
- -- trace "tc5" $
- tcSetEnv env $
+ buildInstanceEnv inst_info `thenNF_Tc` \ inst_env ->
+
+ tcSetInstEnv inst_env $
+ let
+ classes = getEnvClasses env
+ tycons = getEnvTyCons env -- INCLUDES tycons derived from classes
+ local_classes = filter isLocallyDefined classes
+ local_tycons = [ tc | tc <- tycons,
+ isLocallyDefined tc,
+ Nothing <- [tyConClass_maybe tc]
+ ]
+ -- For local_tycons, filter out the ones derived from classes
+ -- Otherwise the latter show up in interface files
+ in
-- Default declarations
tcDefaults decls `thenTc` \ defaulting_tys ->
tcSetDefaultTys defaulting_tys $
+ -- Interface type signatures
+ -- We tie a knot so that the Ids read out of interfaces are in scope
+ -- when we read their pragmas.
+ -- 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
+ -- We must do this before mkImplicitDataBinds (which comes next), since
+ -- the latter looks up unpackCStringId, for example, which is usually
+ -- imported
+ tcInterfaceSigs unf_env decls `thenTc` \ sig_ids ->
+ tcExtendGlobalValEnv sig_ids $
+
-- Create any necessary record selector Ids and their bindings
-- "Necessary" includes data and newtype declarations
- let
- tycons = getEnv_TyCons env
- classes = getEnv_Classes env
- in
- mkDataBinds tycons `thenTc` \ (data_ids, data_binds) ->
+ -- We don't create bindings for dictionary constructors;
+ -- they are always fully applied, and the bindings are just there
+ -- to support partial applications
+ mkImplicitDataBinds tycons `thenTc` \ (data_ids, imp_data_binds) ->
+ mkImplicitClassBinds classes `thenNF_Tc` \ (cls_ids, imp_cls_binds) ->
-- Extend the global value environment with
-- (a) constructors
-- (b) record selectors
-- (c) class op selectors
- -- (d) default-method ids
- tcExtendGlobalValEnv data_ids $
- tcExtendGlobalValEnv (concat (map classSelIds classes)) $
-
-
- -- Interface type signatures
- -- We tie a knot so that the Ids read out of interfaces are in scope
- -- when we read their pragmas.
- -- 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 unf_env decls `thenTc` \ sig_ids ->
- tcExtendGlobalValEnv sig_ids $
+ -- (d) default-method ids... where? I can't see where these are
+ -- put into the envt, and I'm worried that the zonking phase
+ -- will find they aren't there and complain.
+ tcExtendGlobalValEnv data_ids $
+ tcExtendGlobalValEnv cls_ids $
+ -- foreign import declarations next.
+ tcForeignImports decls `thenTc` \ (fo_ids, foi_decls) ->
+ tcExtendGlobalValEnv fo_ids $
-- Value declarations next.
-- We also typecheck any extra binds that came out of the "deriving" process
- -- trace "tcBinds:" $
- tcBindsAndThen
+ tcTopBindsAndThen
(\ is_rec binds1 (binds2, thing) -> (binds1 `AndMonoBinds` binds2, thing))
(get_val_decls decls `ThenBinds` deriv_binds)
- ( tcGetEnv `thenNF_Tc` \ env ->
+ ( tcGetEnv `thenNF_Tc` \ env ->
+ tcGetUnique `thenNF_Tc` \ uniq ->
returnTc ((EmptyMonoBinds, env), emptyLIE)
) `thenTc` \ ((val_binds, final_env), lie_valdecls) ->
tcSetEnv final_env $
+ -- foreign export declarations next.
+ tcForeignExports decls `thenTc` \ (lie_fodecls, foe_binds, foe_decls) ->
-- Second pass over class and instance declarations,
-- to compile the bindings themselves.
- -- trace "tc8" $
tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) ->
- tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_binds) ->
+ tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_dm_binds) ->
+ tcRules decls `thenNF_Tc` \ (lie_rules, rules) ->
-
- -- Check that "main" has the right signature
- tcCheckMainSig mod_name `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" $
let
- lie_alldecls = lie_valdecls `plusLIE` lie_instdecls `plusLIE` lie_clasdecls
+ lie_alldecls = lie_valdecls `plusLIE`
+ lie_instdecls `plusLIE`
+ lie_clasdecls `plusLIE`
+ lie_fodecls `plusLIE`
+ lie_rules
in
tcSimplifyTop lie_alldecls `thenTc` \ const_inst_binds ->
+ -- Check that Main defines main
+ (if mod_name == mAIN_Name then
+ tcLookupValueByKeyMaybe mainKey `thenNF_Tc` \ maybe_main ->
+ checkTc (maybeToBool maybe_main) noMainErr
+ else
+ returnTc ()
+ ) `thenTc_`
-- Backsubstitution. This must be done last.
- -- Even tcCheckMainSig and tcSimplifyTop may do some unification.
+ -- Even tcSimplifyTop may do some unification.
let
- all_binds = data_binds `AndMonoBinds`
+ all_binds = imp_data_binds `AndMonoBinds`
+ imp_cls_binds `AndMonoBinds`
val_binds `AndMonoBinds`
inst_binds `AndMonoBinds`
- cls_binds `AndMonoBinds`
- const_inst_binds
+ cls_dm_binds `AndMonoBinds`
+ const_inst_binds `AndMonoBinds`
+ foe_binds
in
- zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', really_final_env) ->
-
- returnTc (really_final_env, (all_binds', inst_info, ddump_deriv))
+ zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', really_final_env) ->
+ tcSetValueEnv really_final_env $
+ zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' ->
+ zonkRules rules `thenNF_Tc` \ rules' ->
+
+ returnTc (really_final_env,
+ (TcResults { tc_binds = all_binds',
+ tc_tycons = local_tycons,
+ tc_classes = local_classes,
+ tc_insts = inst_info,
+ tc_fords = foi_decls ++ foe_decls',
+ tc_rules = rules',
+ tc_env = really_final_env
+ }))
-- End of outer fix loop
- ) `thenTc` \ (final_env, (all_binds', inst_info, ddump_deriv)) ->
-
-
- let
- tycons = getEnv_TyCons final_env
- classes = getEnv_Classes final_env
-
- local_tycons = filter isLocallyDefined tycons
- local_classes = filter isLocallyDefined classes
- in
- -- FINISHED AT LAST
- returnTc (
- all_binds',
-
- local_tycons, local_classes, inst_info, tycon_specs,
-
- ddump_deriv
- )
+ ) `thenTc` \ (final_env, stuff) ->
+ returnTc stuff
get_val_decls decls = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls]
\end{code}
\begin{code}
-tcCheckMainSig mod_name
- | mod_name /= mAIN
- = returnTc () -- A non-main module
-
- | otherwise
- = -- Check that main is defined
- tcLookupTyCon ioTyCon_NAME `thenTc` \ (_,_,ioTyCon) ->
- tcLookupLocalValue main_NAME `thenNF_Tc` \ maybe_main_id ->
- case maybe_main_id of {
- Nothing -> failTc noMainErr;
- Just main_id ->
-
- -- Check that it has the right type (or a more general one)
- let expected_ty = applyTyCon ioTyCon [unitTy] in
- tcInstType [] expected_ty `thenNF_Tc` \ expected_tau ->
- tcId main_NAME `thenNF_Tc` \ (_, lie, main_tau) ->
- tcSetErrCtxt mainTyCheckCtxt $
- unifyTauTy expected_tau
- main_tau `thenTc_`
- checkTc (isEmptyBag lie) (mainTyMisMatch expected_ty (idType main_id))
- }
-
-mainTyCheckCtxt sty
- = hsep [ptext SLIT("When checking that"), ppr sty main_NAME,
- ptext SLIT("has the required type")]
-
-noMainErr sty
- = hsep [ptext SLIT("Module"), pprModule sty mAIN,
- ptext SLIT("must include a definition for"), ppr sty main_NAME]
-
-mainTyMisMatch :: Type -> TcType s -> Error
-mainTyMisMatch expected actual sty
- = hang (hsep [ppr sty main_NAME, ptext SLIT("has the wrong type")])
- 4 (vcat [
- hsep [ptext SLIT("Expected:"), ppr sty expected],
- hsep [ptext SLIT("Inferred:"), ppr sty actual]
- ])
+noMainErr
+ = hsep [ptext SLIT("Module"), quotes (pprModuleName mAIN_Name),
+ ptext SLIT("must include a definition for"), quotes (ptext SLIT("main"))]
\end{code}
+