\begin{code}
module TcModule (
typecheckModule,
- TcResults,
- TcDDumpDeriv
+ TcResults(..)
) where
#include "HsVersions.h"
-import CmdLineOpts ( opt_D_dump_tc, opt_D_dump_deriv )
+import CmdLineOpts ( DynFlag(..), DynFlags, opt_PprStyle_Debug )
import HsSyn ( HsModule(..), HsBinds(..), MonoBinds(..), HsDecl(..) )
-import RnHsSyn ( RenamedHsModule )
-import TcHsSyn ( TcMonoBinds, TypecheckedMonoBinds, zonkTopBinds,
- TypecheckedForeignDecl, zonkForeignExports
+import HsTypes ( toHsType )
+import RnHsSyn ( RenamedHsModule, RenamedHsDecl )
+import TcHsSyn ( TypecheckedMonoBinds,
+ TypecheckedForeignDecl, TypecheckedRuleDecl,
+ zonkTopBinds, zonkForeignExports, zonkRules
)
import TcMonad
-import Inst ( Inst, emptyLIE, plusLIE )
-import TcBinds ( tcTopBindsAndThen )
-import TcClassDcl ( tcClassDecls2 )
+import Inst ( emptyLIE, plusLIE )
+import TcBinds ( tcTopBinds )
+import TcClassDcl ( tcClassDecls2, mkImplicitClassBinds )
import TcDefaults ( tcDefaults )
-import TcEnv ( TcIdOcc(..), tcExtendGlobalValEnv, tcExtendTyConEnv,
- getEnv_TyCons, getEnv_Classes, tcLookupLocalValue,
- lookupGlobalByKey, tcSetGlobalValEnv,
- tcLookupTyCon, initEnv, GlobalValueEnv
+import TcEnv ( TcEnv, tcExtendGlobalValEnv, tcLookupGlobal_maybe,
+ tcEnvTyCons, tcEnvClasses,
+ tcSetEnv, tcSetInstEnv, initTcEnv, getTcGEnv
)
-import TcExpr ( tcId )
+import TcRules ( tcRules )
import TcForeign ( tcForeignImports, tcForeignExports )
import TcIfaceSig ( tcInterfaceSigs )
import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
-import TcInstUtil ( buildInstanceEnvs, classDataCon, InstInfo )
+import InstEnv ( InstInfo(..) )
import TcSimplify ( tcSimplifyTop )
-import TcTyClsDecls ( tcTyAndClassDecls1 )
-import TcTyDecls ( mkDataBinds )
-import TcType ( TcType, typeToTcType,
- TcKind, kindToTcKind
- )
+import TcTyClsDecls ( tcTyAndClassDecls )
+import TcTyDecls ( mkImplicitDataBinds )
-import RnMonad ( RnNameSupply )
+import CoreUnfold ( unfoldingTemplate )
+import Type ( funResultTy, splitForAllTys )
import Bag ( isEmptyBag )
-import ErrUtils ( ErrMsg,
- pprBagOfErrors, dumpIfSet
- )
-import Id ( Id, idType )
-import Name ( Name, nameUnique, isLocallyDefined, pprModule, NamedThing(..) )
-import TyCon ( TyCon, tyConKind )
-import DataCon ( dataConId )
-import Class ( Class, classSelIds, classTyCon )
-import Type ( mkTyConApp, Type )
-import TysWiredIn ( unitTy )
-import PrelMods ( mAIN )
-import PrelInfo ( main_NAME, ioTyCon_NAME,
- thinAirIdNames, setThinAirIds
+import ErrUtils ( printErrorsAndWarnings, dumpIfSet_dyn )
+import Id ( idType, idName, idUnfolding )
+import Module ( Module, moduleName, plusModuleEnv )
+import Name ( Name, nameOccName, isLocallyDefined, isGlobalName,
+ toRdrName, nameEnvElts, emptyNameEnv, lookupNameEnv
)
-import TcUnify ( unifyTauTy )
-import Unique ( Unique )
+import TyCon ( TyCon, isDataTyCon, tyConName, tyConGenInfo )
+import OccName ( isSysOcc )
+import TyCon ( TyCon, isClassTyCon )
+import Class ( Class )
+import PrelNames ( mAIN_Name, mainName )
import UniqSupply ( UniqSupply )
+import Maybes ( maybeToBool, thenMaybe )
import Util
+import BasicTypes ( EP(..), Fixity )
import Bag ( Bag, isEmptyBag )
import Outputable
-
-import IOExts
+import HscTypes ( PersistentCompilerState(..), HomeSymbolTable, HomeIfaceTable,
+ PackageSymbolTable, PackageIfaceTable, DFunId, ModIface(..),
+ TypeEnv, extendTypeEnv, lookupTable,
+ TyThing(..), groupTyThings )
+import FiniteMap ( FiniteMap, delFromFM, lookupWithDefaultFM )
\end{code}
Outside-world interface:
\begin{code}
-- Convenient type synonyms first:
-type TcResults
- = (TypecheckedMonoBinds,
- [TyCon], [Class],
- Bag InstInfo, -- Instance declaration information
- [TypecheckedForeignDecl], -- foreign import & exports.
- TcDDumpDeriv,
- GlobalValueEnv,
- [Id] -- The thin-air Ids
- )
-
-type TcDDumpDeriv = SDoc
+data TcResults
+ = TcResults {
+ tc_pcs :: PersistentCompilerState, -- Augmented with imported information,
+ -- (but not stuff from this module)
+ tc_env :: TypeEnv, -- The TypeEnv just for the stuff from this module
+ tc_insts :: [DFunId], -- Instances, just for this module
+ tc_binds :: TypecheckedMonoBinds,
+ tc_fords :: [TypecheckedForeignDecl], -- Foreign import & exports.
+ tc_rules :: [TypecheckedRuleDecl] -- Transformation rules
+ }
---------------
typecheckModule
- :: UniqSupply
- -> RnNameSupply
+ :: DynFlags
+ -> Module
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> HomeIfaceTable
+ -> PackageIfaceTable
-> RenamedHsModule
- -> IO (Maybe TcResults)
-
-typecheckModule us rn_name_supply mod
- = let
- (maybe_result, warns, errs) =
- initTc us initEnv (tcModule rn_name_supply mod)
- in
- print_errs warns >>
- print_errs errs >>
-
- dumpIfSet opt_D_dump_tc "Typechecked"
- (case maybe_result of
- Just (binds, _, _, _, _, _, _, _) -> ppr binds
- Nothing -> text "Typecheck failed") >>
-
- dumpIfSet opt_D_dump_deriv "Derived instances"
- (case maybe_result of
- Just (_, _, _, _, _, dump_deriv, _, _) -> dump_deriv
- Nothing -> empty) >>
-
- -- write the thin-air Id map
- (case maybe_result of
- Just (_, _, _, _, _, _, _, thin_air_ids) -> setThinAirIds thin_air_ids
- Nothing -> return ()
- ) >>
-
- return (if isEmptyBag errs then
- maybe_result
- else
- Nothing)
-
-print_errs errs
- | isEmptyBag errs = return ()
- | otherwise = printErrs (pprBagOfErrors errs)
+ -> IO (Maybe (TcEnv, TcResults))
+
+typecheckModule dflags this_mod pcs hst hit pit (HsModule mod_name _ _ _ decls _ src_loc)
+ = do env <- initTcEnv global_symbol_table
+ (maybe_result, (errs,warns)) <- initTc dflags env src_loc tc_module
+ printErrorsAndWarnings (errs,warns)
+ printTcDump dflags maybe_result
+ if isEmptyBag errs then
+ return Nothing
+ else
+ return maybe_result
+ where
+ global_symbol_table = pcs_PST pcs `plusModuleEnv` hst
+
+ tc_module = fixTc (\ ~(unf_env ,_)
+ -> tcModule pcs hst get_fixity this_mod decls unf_env)
+
+ get_fixity :: Name -> Maybe Fixity
+ get_fixity nm = lookupTable hit pit nm `thenMaybe` \ iface ->
+ lookupNameEnv (mi_fixities iface) nm
\end{code}
The internal monster:
\begin{code}
-tcModule :: RnNameSupply -- for renaming derivings
- -> RenamedHsModule -- input
- -> TcM s TcResults -- output
-
-tcModule rn_name_supply
- (HsModule mod_name verion exports imports fixities decls src_loc)
- = tcAddSrcLoc src_loc $ -- record where we're starting
-
- fixTc (\ ~(unf_env ,_) ->
- -- unf_env is used for type-checking interface pragmas
- -- 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 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, _, _, _, _) ->
+tcModule :: PersistentCompilerState
+ -> HomeSymbolTable
+ -> (Name -> Maybe Fixity)
+ -> Module
+ -> [RenamedHsDecl]
+ -> TcEnv -- The knot-tied environment
+ -> TcM (TcEnv, TcResults)
+
+ -- (unf_env :: TcEnv) is used for type-checking interface pragmas
+ -- which is done lazily [ie failure just drops the pragma
+ -- without having any global-failure effect].
+ --
+ -- unf_env is also used to get the pragama info
+ -- for imported dfuns and default methods
+
+tcModule pcs hst get_fixity this_mod decls unf_env
+ = -- Type-check the type and class decls
+ tcTyAndClassDecls unf_env decls `thenTc` \ env ->
+ tcSetEnv env $
+ let
+ classes = tcEnvClasses env
+ tycons = tcEnvTyCons env -- INCLUDES tycons derived from classes
+ local_classes = filter isLocallyDefined classes
+ local_tycons = [ tc | tc <- tycons,
+ isLocallyDefined tc,
+ not (isClassTyCon tc)
+ ]
+ -- For local_tycons, filter out the ones derived from classes
+ -- Otherwise the latter show up in interface files
+ in
- -- Type-check the type and class decls
- -- trace "tcTyAndClassDecls:" $
- tcTyAndClassDecls1 unf_env rec_inst_mapper decls `thenTc` \ env ->
+ -- Typecheck the instance decls, includes deriving
+ tcInstDecls1 pcs hst unf_env get_fixity this_mod
+ local_tycons decls `thenTc` \ (pcs_with_insts, inst_env, inst_info, deriv_binds) ->
+ tcSetInstEnv inst_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) ->
+ -- Default declarations
+ tcDefaults decls `thenTc` \ defaulting_tys ->
+ tcSetDefaultTys defaulting_tys $
- -- trace "tc4" $
- buildInstanceEnvs inst_info `thenNF_Tc` \ inst_mapper ->
+ -- 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 $
- returnTc (inst_mapper, env, inst_info, deriv_binds, ddump_deriv)
+ -- Create any necessary record selector Ids and their bindings
+ -- "Necessary" includes data and newtype declarations
+ -- 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) ->
- -- End of inner fix loop
- ) `thenTc` \ (_, env, inst_info, deriv_binds, ddump_deriv) ->
+ -- Extend the global value environment with
+ -- (a) constructors
+ -- (b) record selectors
+ -- (c) class op selectors
+ -- (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 $
- -- trace "tc5" $
- tcSetEnv env $
-
- -- Default declarations
- tcDefaults decls `thenTc` \ defaulting_tys ->
- tcSetDefaultTys defaulting_tys $
-
- -- Create any necessary record selector Ids and their bindings
- -- "Necessary" includes data and newtype declarations
- -- We don't create bindings for dictionary constructors;
- -- they are always fully applied, and the bindings are just there
- -- to support partial applications
- let
- tycons = getEnv_TyCons env
- classes = getEnv_Classes env
- local_tycons = filter isLocallyDefined tycons
- local_classes = filter isLocallyDefined classes
- in
- mkDataBinds tycons `thenTc` \ (data_ids, data_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)) $
-
- -- Extend the TyCon envt with the tycons corresponding to
- -- the classes, and the global value environment with the
- -- corresponding data cons.
- -- They are mentioned in types in interface files.
- tcExtendGlobalValEnv (map (dataConId . classDataCon) classes) $
- tcExtendTyConEnv [ (getName tycon, (kindToTcKind (tyConKind tycon), Nothing, tycon))
- | clas <- classes,
- let tycon = classTyCon clas
- ] $
-
- -- 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 $
-
- -- 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 "tc6" $
- tcTopBindsAndThen
- (\ is_rec binds1 (binds2, thing) -> (binds1 `AndMonoBinds` binds2, thing))
- (get_val_decls decls `ThenBinds` deriv_binds)
- ( tcGetEnv `thenNF_Tc` \ env ->
--- tcGetUnique `thenNF_Tc` \ uniq ->
--- pprTrace "tc7" (ppr 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.
--- pprTrace "tc8" emtpy $
- tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) ->
- tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_binds) ->
-
- -- 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.)
- let
- lie_alldecls = lie_valdecls `plusLIE`
- lie_instdecls `plusLIE`
- lie_clasdecls `plusLIE`
- lie_fodecls
- in
- tcSimplifyTop lie_alldecls `thenTc` \ const_inst_binds ->
-
-
- -- Backsubstitution. This must be done last.
- -- Even tcCheckMainSig and tcSimplifyTop may do some unification.
- let
- all_binds = data_binds `AndMonoBinds`
- val_binds `AndMonoBinds`
- inst_binds `AndMonoBinds`
- cls_binds `AndMonoBinds`
- const_inst_binds `AndMonoBinds`
- foe_binds
- in
- zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', really_final_env) ->
- tcSetGlobalValEnv really_final_env $
- zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' ->
-
- let
- thin_air_ids = map (lookupGlobalByKey really_final_env . nameUnique) thinAirIdNames
- -- When looking up the thin-air names we must use
- -- a global env that includes the zonked locally-defined Ids too
- -- Hence using really_final_env
- in
- returnTc (really_final_env,
- (all_binds', local_tycons, local_classes, inst_info,
- foi_decls ++ foe_decls',
- ddump_deriv, really_final_env, thin_air_ids))
-
- -- End of outer fix loop
- ) `thenTc` \ (final_env, stuff) ->
- returnTc stuff
-
-get_val_decls decls = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls]
+ -- 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
+ tcTopBinds (get_binds decls `ThenBinds` deriv_binds) `thenTc` \ ((val_binds, env), lie_valdecls) ->
+ tcSetEnv 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.
+ tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) ->
+ tcClassDecls2 decls `thenNF_Tc` \ (lie_clasdecls, cls_dm_binds) ->
+ tcRules decls `thenNF_Tc` \ (lie_rules, rules) ->
+
+ -- 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.)
+ let
+ 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
+ checkMain this_mod `thenTc_`
+
+ -- Backsubstitution. This must be done last.
+ -- Even tcSimplifyTop may do some unification.
+ let
+ all_binds = imp_data_binds `AndMonoBinds`
+ imp_cls_binds `AndMonoBinds`
+ val_binds `AndMonoBinds`
+ inst_binds `AndMonoBinds`
+ cls_dm_binds `AndMonoBinds`
+ const_inst_binds `AndMonoBinds`
+ foe_binds
+ in
+ zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', final_env) ->
+ tcSetEnv final_env $
+ -- zonkTopBinds puts all the top-level Ids into the tcGEnv
+ zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' ->
+ zonkRules rules `thenNF_Tc` \ rules' ->
+
+
+ let groups :: FiniteMap Module TypeEnv
+ groups = groupTyThings (nameEnvElts (getTcGEnv final_env))
+
+ local_type_env :: TypeEnv
+ local_type_env = lookupWithDefaultFM groups emptyNameEnv this_mod
+
+ new_pst :: PackageSymbolTable
+ new_pst = extendTypeEnv (pcs_PST pcs) (delFromFM groups this_mod)
+
+ final_pcs :: PersistentCompilerState
+ final_pcs = pcs_with_insts {pcs_PST = new_pst}
+ in
+ returnTc (final_env, -- WAS: really_final_env,
+ TcResults { tc_pcs = final_pcs,
+ tc_env = local_type_env,
+ tc_binds = all_binds',
+ tc_insts = map iDFunId inst_info,
+ tc_fords = foi_decls ++ foe_decls',
+ tc_rules = rules'
+ })
+
+get_binds 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 -> failWithTc noMainErr ;
- Just main_id ->
+checkMain :: Module -> TcM ()
+checkMain this_mod
+ | moduleName this_mod == mAIN_Name
+ = tcLookupGlobal_maybe mainName `thenNF_Tc` \ maybe_main ->
+ case maybe_main of
+ Just (AnId _) -> returnTc ()
+ other -> addErrTc noMainErr
- -- Check that it has the right type (or a more general one)
- let
- expected_tau = typeToTcType (mkTyConApp ioTyCon [unitTy])
- in
- tcId main_NAME `thenNF_Tc` \ (_, lie, main_tau) ->
- tcSetErrCtxt mainTyCheckCtxt $
- unifyTauTy expected_tau
- main_tau `thenTc_`
- checkTc (isEmptyBag lie) (mainTyMisMatch expected_tau (idType main_id))
- }
+ | otherwise = returnTc ()
+noMainErr
+ = hsep [ptext SLIT("Module"), quotes (ppr mAIN_Name),
+ ptext SLIT("must include a definition for"), quotes (ptext SLIT("main"))]
+\end{code}
-mainTyCheckCtxt
- = hsep [ptext SLIT("When checking that"), ppr main_NAME, ptext SLIT("has the required type")]
-noMainErr
- = hsep [ptext SLIT("Module"), quotes (pprModule mAIN),
- ptext SLIT("must include a definition for"), quotes (ppr main_NAME)]
+%************************************************************************
+%* *
+\subsection{Dumping output}
+%* *
+%************************************************************************
-mainTyMisMatch :: TcType s -> TcType s -> ErrMsg
-mainTyMisMatch expected actual
- = hang (hsep [ppr main_NAME, ptext SLIT("has the wrong type")])
- 4 (vcat [
- hsep [ptext SLIT("Expected:"), ppr expected],
- hsep [ptext SLIT("Inferred:"), ppr actual]
- ])
+\begin{code}
+printTcDump dflags Nothing = return ()
+printTcDump dflags (Just (_,results))
+ = do dumpIfSet_dyn dflags Opt_D_dump_types
+ "Type signatures" (dump_sigs results)
+ dumpIfSet_dyn dflags Opt_D_dump_tc
+ "Typechecked" (dump_tc results)
+
+dump_tc results
+ = vcat [ppr (tc_binds results),
+ pp_rules (tc_rules results) --,
+-- ppr_gen_tycons (tc_tycons 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))
+ | AnId 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 &&
+ isGlobalName n &&
+ not (isSysOcc (nameOccName n))
+ where
+ n = idName id
+
+ppr_gen_tycons tcs = vcat [ptext SLIT("{-# Generic type constructor details"),
+ vcat (map ppr_gen_tycon (filter isLocallyDefined tcs)),
+ ptext SLIT("#-}")
+ ]
+
+-- x&y are now Id's, not CoreExpr's
+ppr_gen_tycon tycon
+ | Just ep <- tyConGenInfo tycon
+ = (ppr tycon <> colon) $$ nest 4 (ppr_ep ep)
+
+ | otherwise = ppr tycon <> colon <+> ptext SLIT("Not derivable")
+
+ppr_ep (EP from to)
+ = vcat [ ptext SLIT("Rep type:") <+> ppr (funResultTy from_tau),
+ ptext SLIT("From:") <+> ppr (unfoldingTemplate (idUnfolding from)),
+ ptext SLIT("To:") <+> ppr (unfoldingTemplate (idUnfolding to))
+ ]
+ where
+ (_,from_tau) = splitForAllTys (idType from)
+
+pp_rules [] = empty
+pp_rules rs = vcat [ptext SLIT("{-# RULES"),
+ nest 4 (vcat (map ppr rs)),
+ ptext SLIT("#-}")]
\end{code}
projects / ghc-hetmet.git / blobdiff