X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcModule.lhs;h=9baf81bb40e153147f346f4a786feee996c309ec;hb=979947f545d70c63edb7ca96f6e47008ac90e3bf;hp=6a0fb1d649693e23824266008e5ac4d3ae7d4cac;hpb=5e3f005d3012472e422d4ffd7dca5c21a80fca80;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcModule.lhs b/ghc/compiler/typecheck/TcModule.lhs index 6a0fb1d..9baf81b 100644 --- a/ghc/compiler/typecheck/TcModule.lhs +++ b/ghc/compiler/typecheck/TcModule.lhs @@ -15,56 +15,58 @@ module TcModule ( import CmdLineOpts ( DynFlag(..), DynFlags, dopt ) import HsSyn ( HsBinds(..), MonoBinds(..), HsDecl(..), HsExpr(..), Stmt(..), InPat(..), HsMatchContext(..), HsDoContext(..), RuleDecl(..), - isIfaceRuleDecl, nullBinds, mkSimpleMatch, placeHolderType + isSourceInstDecl, mkSimpleMatch, placeHolderType ) -import PrelNames ( mAIN_Name, mainName, ioTyConName, printName, - returnIOName, bindIOName, failIOName, - itName +import PrelNames ( ioTyConName, printName, + returnIOName, bindIOName, failIOName, runMainName, + dollarMainName, itName ) import MkId ( unsafeCoerceId ) -import RnHsSyn ( RenamedHsBinds, RenamedHsDecl, RenamedStmt, - RenamedHsExpr ) +import RnHsSyn ( RenamedHsDecl, RenamedStmt, RenamedHsExpr, + RenamedRuleDecl, RenamedTyClDecl, RenamedInstDecl ) import TcHsSyn ( TypecheckedMonoBinds, TypecheckedHsExpr, TypecheckedForeignDecl, TypecheckedRuleDecl, zonkTopBinds, zonkForeignExports, zonkRules, mkHsLet, zonkExpr, zonkIdBndr ) +import Rename ( RnResult(..) ) import MkIface ( pprModDetails ) import TcExpr ( tcMonoExpr ) import TcMonad -import TcMType ( newTyVarTy, zonkTcType, tcInstType ) +import TcMType ( newTyVarTy, zonkTcType ) import TcType ( Type, liftedTypeKind, openTypeKind, - tyVarsOfType, tidyType, tcFunResultTy, - mkForAllTys, mkFunTys, mkTyConApp, tcSplitForAllTys + tyVarsOfType, tcFunResultTy, + mkForAllTys, mkFunTys, mkTyConApp, tcSplitForAllTys, + tcSplitTyConApp_maybe, isUnitTy ) import TcMatches ( tcStmtsAndThen ) -import Inst ( emptyLIE, plusLIE ) +import Inst ( LIE, emptyLIE, plusLIE ) import TcBinds ( tcTopBinds ) import TcClassDcl ( tcClassDecls2 ) import TcDefaults ( tcDefaults, defaultDefaultTys ) -import TcEnv ( TcEnv, RecTcEnv, InstInfo(iDFunId), tcExtendGlobalValEnv, tcLookup_maybe, +import TcEnv ( TcEnv, RecTcEnv, InstInfo(iDFunId), tcExtendGlobalValEnv, isLocalThing, tcSetEnv, tcSetInstEnv, initTcEnv, getTcGEnv, - tcExtendGlobalTypeEnv, tcLookupGlobalId, tcLookupTyCon, - TcTyThing(..), tcLookupId + tcExtendGlobalEnv, tcExtendGlobalTypeEnv, + tcLookupGlobalId, tcLookupTyCon, + TyThing(..), tcLookupId ) import TcRules ( tcIfaceRules, tcSourceRules ) import TcForeign ( tcForeignImports, tcForeignExports ) import TcIfaceSig ( tcInterfaceSigs ) -import TcInstDcls ( tcInstDecls1, tcInstDecls2 ) -import TcUnify ( unifyTauTy ) +import TcInstDcls ( tcInstDecls1, tcIfaceInstDecls1, addInstDFuns, initInstEnv, tcInstDecls2 ) import TcSimplify ( tcSimplifyTop, tcSimplifyInfer ) import TcTyClsDecls ( tcTyAndClassDecls ) import CoreUnfold ( unfoldingTemplate ) import TysWiredIn ( mkListTy, unitTy ) import ErrUtils ( printErrorsAndWarnings, errorsFound, dumpIfSet_dyn, dumpIfSet_dyn_or, showPass ) -import Id ( Id, idType, idUnfolding ) -import Module ( Module, moduleName ) -import Name ( Name ) -import NameEnv ( lookupNameEnv ) +import Rules ( extendRuleBase ) +import Id ( Id, mkLocalId, idType, idUnfolding, setIdLocalExported ) +import Module ( Module ) +import Name ( Name, getName, getSrcLoc ) import TyCon ( tyConGenInfo ) -import BasicTypes ( EP(..), Fixity, RecFlag(..) ) +import BasicTypes ( EP(..), RecFlag(..) ) import SrcLoc ( noSrcLoc ) import Outputable import IO ( stdout ) @@ -74,6 +76,7 @@ import HscTypes ( PersistentCompilerState(..), HomeSymbolTable, TypeEnv, extendTypeEnvList, typeEnvTyCons, typeEnvElts, mkTypeEnv ) +import List ( partition ) \end{code} @@ -108,10 +111,7 @@ typecheckStmt dflags pcs hst ic_type_env unqual this_mod names (stmt, iface_decl tcSetDefaultTys defaultDefaultTys $ -- Typecheck the extra declarations - fixTc (\ ~(unf_env, _, _, _, _) -> - tcImports unf_env pcs hst get_fixity this_mod iface_decls - ) `thenTc` \ (env, new_pcs, local_inst_info, deriv_binds, local_rules) -> - ASSERT( null local_inst_info && nullBinds deriv_binds && null local_rules ) + tcExtraDecls pcs hst this_mod iface_decls `thenTc` \ (new_pcs, env) -> tcSetEnv env $ tcExtendGlobalTypeEnv ic_type_env $ @@ -127,10 +127,6 @@ typecheckStmt dflags pcs hst ic_type_env unqual this_mod names (stmt, iface_decl ioToTc (dumpIfSet_dyn dflags Opt_D_dump_tc "Typechecked" (ppr zonked_expr)) `thenNF_Tc_` returnTc (new_pcs, zonked_expr, zonked_ids, error "typecheckStmt: no type") - - where - get_fixity :: Name -> Maybe Fixity - get_fixity n = pprPanic "typecheckStmt" (ppr n) \end{code} Here is the grand plan, implemented in tcUserStmt @@ -249,10 +245,7 @@ typecheckExpr dflags pcs hst ic_type_env unqual this_mod (expr, decls) tcSetDefaultTys defaultDefaultTys $ -- Typecheck the extra declarations - fixTc (\ ~(unf_env, _, _, _, _) -> - tcImports unf_env pcs hst get_fixity this_mod decls - ) `thenTc` \ (env, new_pcs, local_inst_info, deriv_binds, local_rules) -> - ASSERT( null local_inst_info && nullBinds deriv_binds && null local_rules ) + tcExtraDecls pcs hst this_mod decls `thenTc` \ (new_pcs, env) -> -- Now typecheck the expression tcSetEnv env $ @@ -282,9 +275,6 @@ typecheckExpr dflags pcs hst ic_type_env unqual this_mod (expr, decls) returnTc (new_pcs, zonked_expr, [], zonked_ty) where - get_fixity :: Name -> Maybe Fixity - get_fixity n = pprPanic "typecheckExpr" (ppr n) - smpl_doc = ptext SLIT("main expression") \end{code} @@ -304,17 +294,40 @@ typecheckExtraDecls -> [RenamedHsDecl] -- extra decls sucked in from interface files -> IO (Maybe PersistentCompilerState) -typecheckExtraDecls dflags pcs hst unqual this_mod decls +typecheckExtraDecls dflags pcs hst unqual this_mod decls = typecheck dflags pcs hst unqual $ - fixTc (\ ~(unf_env, _, _, _, _) -> - tcImports unf_env pcs hst get_fixity this_mod decls - ) `thenTc` \ (env, new_pcs, local_inst_info, deriv_binds, local_rules) -> - ASSERT( null local_inst_info && nullBinds deriv_binds && null local_rules ) - returnTc new_pcs - where - get_fixity n = pprPanic "typecheckExpr" (ppr n) + tcExtraDecls pcs hst this_mod decls `thenTc` \ (new_pcs, _) -> + returnTc new_pcs + +tcExtraDecls :: PersistentCompilerState + -> HomeSymbolTable + -> Module + -> [RenamedHsDecl] + -> TcM (PersistentCompilerState, TcEnv) + -- Returned environment includes instances + +tcExtraDecls pcs hst this_mod decls + = tcIfaceImports this_mod decls `thenTc` \ (env, all_things, dfuns, rules) -> + addInstDFuns (pcs_insts pcs) dfuns `thenNF_Tc` \ new_pcs_insts -> + let + new_pcs_pte = extendTypeEnvList (pcs_PTE pcs) all_things + new_pcs_rules = addIfaceRules (pcs_rules pcs) rules + + new_pcs :: PersistentCompilerState + new_pcs = pcs { pcs_PTE = new_pcs_pte, + pcs_insts = new_pcs_insts, + pcs_rules = new_pcs_rules + } + in + -- Initialise the instance environment + tcSetEnv env ( + initInstEnv new_pcs hst `thenNF_Tc` \ inst_env -> + tcSetInstEnv inst_env tcGetEnv + ) `thenNF_Tc` \ new_env -> + returnTc (new_pcs, new_env) \end{code} + %************************************************************************ %* * \subsection{Typechecking a module} @@ -326,9 +339,8 @@ typecheckModule :: DynFlags -> PersistentCompilerState -> HomeSymbolTable - -> ModIface -- Iface for this module -> PrintUnqualified -- For error printing - -> [RenamedHsDecl] + -> RnResult -> IO (Maybe (PersistentCompilerState, TcResults)) -- The new PCS is Augmented with imported information, -- (but not stuff from this module) @@ -344,27 +356,19 @@ data TcResults } -typecheckModule dflags pcs hst mod_iface unqual decls +typecheckModule dflags pcs hst unqual rn_result = do { maybe_tc_result <- typecheck dflags pcs hst unqual $ - tcModule pcs hst get_fixity this_mod decls + tcModule pcs hst rn_result ; printTcDump dflags unqual maybe_tc_result ; return maybe_tc_result } - where - this_mod = mi_module mod_iface - fixity_env = mi_fixities mod_iface - - get_fixity :: Name -> Maybe Fixity - get_fixity nm = lookupNameEnv fixity_env nm - tcModule :: PersistentCompilerState -> HomeSymbolTable - -> (Name -> Maybe Fixity) - -> Module - -> [RenamedHsDecl] + -> RnResult -> TcM (PersistentCompilerState, TcResults) -tcModule pcs hst get_fixity this_mod decls +tcModule pcs hst (RnResult { rr_decls = decls, rr_mod = this_mod, + rr_fixities = fix_env, rr_main = maybe_main_name }) = fixTc (\ ~(unf_env, _, _) -> -- Loop back the final environment, including the fully zonked -- versions of bindings from this module. In the presence of mutual @@ -372,10 +376,17 @@ tcModule pcs hst get_fixity this_mod decls -- in this module, which is why the knot is so big -- Type-check the type and class decls, and all imported decls - tcImports unf_env pcs hst get_fixity this_mod decls - `thenTc` \ (env, new_pcs, local_insts, deriv_binds, local_rules) -> + tcImports unf_env pcs hst this_mod + tycl_decls iface_inst_decls iface_rule_decls `thenTc` \ (env1, new_pcs) -> + + tcSetEnv env1 $ - tcSetEnv env $ + -- Do the source-language instances, including derivings + initInstEnv new_pcs hst `thenNF_Tc` \ inst_env1 -> + tcInstDecls1 (pcs_PRS new_pcs) inst_env1 + fix_env this_mod + tycl_decls src_inst_decls `thenTc` \ (inst_env2, inst_info, deriv_binds) -> + tcSetInstEnv inst_env2 $ -- Foreign import declarations next traceTc (text "Tc4") `thenNF_Tc_` @@ -390,20 +401,25 @@ tcModule pcs hst get_fixity this_mod decls -- We also typecheck any extra binds that came out of the "deriving" process traceTc (text "Default types" <+> ppr defaulting_tys) `thenNF_Tc_` traceTc (text "Tc5") `thenNF_Tc_` - tcTopBinds (val_binds `ThenBinds` deriv_binds) `thenTc` \ ((val_binds, env), lie_valdecls) -> + tcTopBinds (val_binds `ThenBinds` deriv_binds) `thenTc` \ ((val_binds, env2), lie_valdecls) -> -- Second pass over class and instance declarations, -- plus rules and foreign exports, to generate bindings - tcSetEnv env $ + tcSetEnv env2 $ + traceTc (text "Tc6") `thenNF_Tc_` + traceTc (ppr (getTcGEnv env2)) `thenNF_Tc_` tcClassDecls2 this_mod tycl_decls `thenNF_Tc` \ (lie_clasdecls, cls_dm_binds, dm_ids) -> tcExtendGlobalValEnv dm_ids $ - tcInstDecls2 local_insts `thenNF_Tc` \ (lie_instdecls, inst_binds) -> + traceTc (text "Tc7") `thenNF_Tc_` + tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) -> + traceTc (text "Tc8") `thenNF_Tc_` tcForeignExports decls `thenTc` \ (lie_fodecls, foe_binds, foe_decls) -> - tcSourceRules source_rules `thenNF_Tc` \ (lie_rules, more_local_rules) -> + traceTc (text "Tc9") `thenNF_Tc_` + tcSourceRules src_rule_decls `thenNF_Tc` \ (lie_rules, src_rules) -> -- CHECK THAT main IS DEFINED WITH RIGHT TYPE, IF REQUIRED - traceTc (text "Tc6") `thenNF_Tc_` - tcCheckMain this_mod `thenTc_` + traceTc (text "Tc10") `thenNF_Tc_` + tcCheckMain maybe_main_name `thenTc` \ (main_bind, lie_main) -> -- Deal with constant or ambiguous InstIds. How could -- there be ambiguous ones? They can only arise if a @@ -424,19 +440,21 @@ tcModule pcs hst get_fixity this_mod decls lie_instdecls `plusLIE` lie_clasdecls `plusLIE` lie_fodecls `plusLIE` - lie_rules + lie_rules `plusLIE` + lie_main in tcSimplifyTop lie_alldecls `thenTc` \ const_inst_binds -> - traceTc (text "endsimpltop") `thenTc_` + traceTc (text "endsimpltop") `thenTc_` -- Backsubstitution. This must be done last. -- Even tcSimplifyTop may do some unification. let - all_binds = val_binds `AndMonoBinds` - inst_binds `AndMonoBinds` - cls_dm_binds `AndMonoBinds` - const_inst_binds `AndMonoBinds` - foe_binds + all_binds = val_binds `AndMonoBinds` + inst_binds `AndMonoBinds` + cls_dm_binds `AndMonoBinds` + const_inst_binds `AndMonoBinds` + foe_binds `AndMonoBinds` + main_bind in traceTc (text "Tc7") `thenNF_Tc_` zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', final_env) -> @@ -445,32 +463,33 @@ tcModule pcs hst get_fixity this_mod decls traceTc (text "Tc8") `thenNF_Tc_` zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' -> traceTc (text "Tc9") `thenNF_Tc_` - zonkRules more_local_rules `thenNF_Tc` \ more_local_rules' -> + zonkRules src_rules `thenNF_Tc` \ src_rules' -> - let local_things = filter (isLocalThing this_mod) (typeEnvElts (getTcGEnv final_env)) - - local_type_env :: TypeEnv - local_type_env = mkTypeEnv local_things - - all_local_rules = local_rules ++ more_local_rules' + let src_things = filter (isLocalThing this_mod) (typeEnvElts (getTcGEnv final_env)) + -- This is horribly crude; the env might be jolly big in traceTc (text "Tc10") `thenNF_Tc_` returnTc (final_env, new_pcs, - TcResults { tc_env = local_type_env, - tc_insts = map iDFunId local_insts, + TcResults { tc_env = mkTypeEnv src_things, + tc_insts = map iDFunId inst_info, tc_binds = all_binds', tc_fords = foi_decls ++ foe_decls', - tc_rules = all_local_rules + tc_rules = src_rules' } ) ) `thenTc` \ (_, pcs, tc_result) -> returnTc (pcs, tc_result) where - tycl_decls = [d | TyClD d <- decls] - val_binds = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls] - source_rules = [d | RuleD d <- decls, not (isIfaceRuleDecl d)] + tycl_decls = [d | TyClD d <- decls] + rule_decls = [d | RuleD d <- decls] + inst_decls = [d | InstD d <- decls] + val_decls = [d | ValD d <- decls] + + (src_inst_decls, iface_inst_decls) = partition isSourceInstDecl inst_decls + (src_rule_decls, iface_rule_decls) = partition (isSourceRuleDecl this_mod) rule_decls + val_binds = foldr ThenBinds EmptyBinds val_decls \end{code} @@ -493,51 +512,96 @@ typecheckIface typecheckIface dflags pcs hst mod_iface decls = do { maybe_tc_stuff <- typecheck dflags pcs hst alwaysQualify $ - tcIfaceImports pcs hst get_fixity this_mod decls + tcIface pcs this_mod decls ; printIfaceDump dflags maybe_tc_stuff ; return maybe_tc_stuff } where - this_mod = mi_module mod_iface - fixity_env = mi_fixities mod_iface - - get_fixity :: Name -> Maybe Fixity - get_fixity nm = lookupNameEnv fixity_env nm - - tcIfaceImports pcs hst get_fixity this_mod decls - = fixTc (\ ~(unf_env, _, _, _, _) -> - tcImports unf_env pcs hst get_fixity this_mod decls - ) `thenTc` \ (env, new_pcs, local_inst_info, - deriv_binds, local_rules) -> - ASSERT(nullBinds deriv_binds) - let - local_things = filter (isLocalThing this_mod) (typeEnvElts (getTcGEnv env)) - - mod_details = ModDetails { md_types = mkTypeEnv local_things, - md_insts = map iDFunId local_inst_info, - md_rules = [(id,rule) | IfaceRuleOut id rule <- local_rules], - md_binds = [] } + this_mod = mi_module mod_iface + +tcIface pcs this_mod decls +-- The decls are coming from this_mod's interface file, together +-- with imported interface decls that belong in the "package" stuff. +-- (With GHCi, all the home modules have already been processed.) +-- That is why we need to do the partitioning below. + = tcIfaceImports this_mod decls `thenTc` \ (_, all_things, dfuns, rules) -> + + let + -- Do the partitioning (see notes above) + (local_things, imported_things) = partition (isLocalThing this_mod) all_things + (local_rules, imported_rules) = partition is_local_rule rules + (local_dfuns, imported_dfuns) = partition (isLocalThing this_mod) dfuns + is_local_rule (IfaceRuleOut n _) = isLocalThing this_mod n + in + addInstDFuns (pcs_insts pcs) imported_dfuns `thenNF_Tc` \ new_pcs_insts -> + let + new_pcs_pte :: PackageTypeEnv + new_pcs_pte = extendTypeEnvList (pcs_PTE pcs) imported_things + new_pcs_rules = addIfaceRules (pcs_rules pcs) imported_rules + + new_pcs :: PersistentCompilerState + new_pcs = pcs { pcs_PTE = new_pcs_pte, + pcs_insts = new_pcs_insts, + pcs_rules = new_pcs_rules + } + + mod_details = ModDetails { md_types = mkTypeEnv local_things, + md_insts = local_dfuns, + md_rules = [(id,rule) | IfaceRuleOut id rule <- local_rules], + md_binds = [] } -- All the rules from an interface are of the IfaceRuleOut form - in - returnTc (new_pcs, mod_details) + in + returnTc (new_pcs, mod_details) + + +tcIfaceImports :: Module + -> [RenamedHsDecl] -- All interface-file decls + -> TcM (TcEnv, [TyThing], [DFunId], [TypecheckedRuleDecl]) +tcIfaceImports this_mod decls +-- The decls are all interface-file declarations + = let + inst_decls = [d | InstD d <- decls] + tycl_decls = [d | TyClD d <- decls] + rule_decls = [d | RuleD d <- decls] + in + fixTc (\ ~(unf_env, _, _, _) -> + -- This fixTc follows the same general plan as tcImports, + -- which is better commented (below) + tcTyAndClassDecls unf_env this_mod tycl_decls `thenTc` \ tycl_things -> + tcExtendGlobalEnv tycl_things $ + tcInterfaceSigs unf_env this_mod tycl_decls `thenTc` \ sig_ids -> + tcExtendGlobalValEnv sig_ids $ + tcIfaceInstDecls1 inst_decls `thenTc` \ dfuns -> + tcIfaceRules rule_decls `thenTc` \ rules -> + tcGetEnv `thenTc` \ env -> + let + all_things = map AnId sig_ids ++ tycl_things + in + returnTc (env, all_things, dfuns, rules) + ) + tcImports :: RecTcEnv -> PersistentCompilerState -> HomeSymbolTable - -> (Name -> Maybe Fixity) -> Module - -> [RenamedHsDecl] - -> TcM (TcEnv, PersistentCompilerState, [InstInfo], - RenamedHsBinds, [TypecheckedRuleDecl]) + -> [RenamedTyClDecl] + -> [RenamedInstDecl] + -> [RenamedRuleDecl] + -> TcM (TcEnv, PersistentCompilerState) -- tcImports is a slight mis-nomer. -- It deals with everything that could be an import: --- type and class decls +-- type and class decls (some source, some imported) -- interface signatures (checked lazily) --- instance decls --- rule decls +-- instance decls (some source, some imported) +-- rule decls (all imported) -- These can occur in source code too, of course +-- +-- tcImports is only called when processing source code, +-- so that any interface-file declarations are for other modules, not this one -tcImports unf_env pcs hst get_fixity this_mod decls +tcImports unf_env pcs hst this_mod + tycl_decls inst_decls rule_decls -- (unf_env :: RecTcEnv) is used for type-checking interface pragmas -- which is done lazily [ie failure just drops the pragma -- without having any global-failure effect]. @@ -550,55 +614,62 @@ tcImports unf_env pcs hst get_fixity this_mod decls -- an error we'd better stop now, to avoid a cascade traceTc (text "Tc1") `thenNF_Tc_` - tcTyAndClassDecls unf_env this_mod tycl_decls `thenTc` \ env -> - tcSetEnv env $ + tcTyAndClassDecls unf_env this_mod tycl_decls `thenTc` \ tycl_things -> + tcExtendGlobalEnv tycl_things $ - -- Typecheck the instance decls, includes deriving - traceTc (text "Tc2") `thenNF_Tc_` - tcInstDecls1 (pcs_insts pcs) (pcs_PRS pcs) - hst unf_env get_fixity this_mod - decls `thenTc` \ (new_pcs_insts, inst_env, local_insts, deriv_binds) -> - tcSetInstEnv inst_env $ - - -- 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 - traceTc (text "Tc3") `thenNF_Tc_` + -- 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 + traceTc (text "Tc2") `thenNF_Tc_` tcInterfaceSigs unf_env this_mod tycl_decls `thenTc` \ sig_ids -> tcExtendGlobalValEnv sig_ids $ + -- Typecheck the instance decls, includes deriving + -- Note that imported dictionary functions are already + -- in scope from the preceding tcInterfaceSigs + traceTc (text "Tc3") `thenNF_Tc_` + tcIfaceInstDecls1 inst_decls `thenTc` \ dfuns -> + tcIfaceRules rule_decls `thenNF_Tc` \ rules -> - tcIfaceRules unf_env (pcs_rules pcs) this_mod iface_rules `thenNF_Tc` \ (new_pcs_rules, local_rules) -> - -- When relinking this module from its interface-file decls - -- we'll have IfaceRules that are in fact local to this module - -- That's the reason we we get any local_rules out here - - tcGetEnv `thenTc` \ unf_env -> + addInstDFuns (pcs_insts pcs) dfuns `thenNF_Tc` \ new_pcs_insts -> + tcGetEnv `thenTc` \ unf_env -> let - all_things = typeEnvElts (getTcGEnv unf_env) - -- sometimes we're compiling in the context of a package module -- (on the GHCi command line, for example). In this case, we -- want to treat everything we pulled in as an imported thing. - imported_things - = filter (not . isLocalThing this_mod) all_things + imported_things = map AnId sig_ids ++ -- All imported + filter (not . isLocalThing this_mod) tycl_things new_pte :: PackageTypeEnv new_pte = extendTypeEnvList (pcs_PTE pcs) imported_things + new_pcs_rules = addIfaceRules (pcs_rules pcs) rules + new_pcs :: PersistentCompilerState new_pcs = pcs { pcs_PTE = new_pte, pcs_insts = new_pcs_insts, pcs_rules = new_pcs_rules } in - returnTc (unf_env, new_pcs, local_insts, deriv_binds, local_rules) + returnTc (unf_env, new_pcs) + +isSourceRuleDecl :: Module -> RenamedRuleDecl -> Bool +-- This is a bit gruesome. +-- Usually, HsRules come only from source files; IfaceRules only from interface files +-- But built-in rules appear as an IfaceRuleOut... and when compiling +-- the source file for that built-in rule, we want to treat it as a source +-- rule, so it gets put with the other rules for that module. +isSourceRuleDecl this_mod (HsRule _ _ _ _ _ _) = True +isSourceRuleDecl this_mod (IfaceRule _ _ _ n _ _ _) = False +isSourceRuleDecl this_mod (IfaceRuleOut name _) = isLocalThing this_mod name + +addIfaceRules rule_base rules + = foldl add_rule rule_base rules where - tycl_decls = [d | TyClD d <- decls] - iface_rules = [d | RuleD d <- decls, isIfaceRuleDecl d] + add_rule rule_base (IfaceRuleOut id rule) = extendRuleBase rule_base (id, rule) \end{code} @@ -609,48 +680,43 @@ tcImports unf_env pcs hst get_fixity this_mod decls %************************************************************************ We must check that in module Main, - a) main is defined - b) main :: forall a1...an. IO t, for some type t + a) Main.main is in scope + b) Main.main :: forall a1...an. IO t, for some type t -If we have - main = error "Urk" -then the type of main will be - main :: forall a. a -and that should pass the test too. +Then we build + $main = PrelTopHandler.runMain Main.main -So we just instantiate the type and unify with IO t, and declare -victory if doing so succeeds. +The function + PrelTopHandler :: IO a -> IO () +catches the top level exceptions. +It accepts a Main.main of any type (IO a). \begin{code} -tcCheckMain :: Module -> TcM () -tcCheckMain this_mod - | not (moduleName this_mod == mAIN_Name ) - = returnTc () - - | otherwise - = -- First unify the main_id with IO t, for any old t - tcLookup_maybe mainName `thenNF_Tc` \ maybe_thing -> - case maybe_thing of - Just (ATcId main_id) -> check_main_ty (idType main_id) - other -> addErrTc noMainErr +tcCheckMain :: Maybe Name -> TcM (TypecheckedMonoBinds, LIE) +tcCheckMain Nothing = returnTc (EmptyMonoBinds, emptyLIE) + +tcCheckMain (Just main_name) + = tcLookupId main_name `thenNF_Tc` \ main_id -> + -- If it is not Nothing, it should be in the env + tcAddSrcLoc (getSrcLoc main_id) $ + tcAddErrCtxt mainCtxt $ + newTyVarTy liftedTypeKind `thenNF_Tc` \ ty -> + tcMonoExpr rhs ty `thenTc` \ (main_expr, lie) -> + zonkTcType ty `thenNF_Tc` \ ty -> + ASSERT( is_io_unit ty ) + let + dollar_main_id = setIdLocalExported (mkLocalId dollarMainName ty) + in + returnTc (VarMonoBind dollar_main_id main_expr, lie) where - check_main_ty main_ty - = tcInstType main_ty `thenNF_Tc` \ (tvs, theta, main_tau) -> - newTyVarTy liftedTypeKind `thenNF_Tc` \ arg_ty -> - tcLookupTyCon ioTyConName `thenNF_Tc` \ ioTyCon -> - tcAddErrCtxtM (mainTypeCtxt main_ty) $ - if not (null theta) then - failWithTc empty -- Context has the error message - else - unifyTauTy main_tau (mkTyConApp ioTyCon [arg_ty]) - -mainTypeCtxt main_ty tidy_env - = zonkTcType main_ty `thenNF_Tc` \ main_ty' -> - returnNF_Tc (tidy_env, ptext SLIT("`main' has the illegal type") <+> - quotes (ppr (tidyType tidy_env main_ty'))) - -noMainErr = hsep [ptext SLIT("Module") <+> quotes (ppr mAIN_Name), - ptext SLIT("must include a definition for") <+> quotes (ptext SLIT("main"))] + rhs = HsApp (HsVar runMainName) (HsVar main_name) + +is_io_unit :: Type -> Bool -- True for IO () +is_io_unit tau = case tcSplitTyConApp_maybe tau of + Just (tc, [arg]) -> getName tc == ioTyConName && isUnitTy arg + other -> False + +mainCtxt = ptext SLIT("When checking the type of 'main'") \end{code}