\begin{code}
module TcModule (
- typecheckModule,
+ typecheckModule, typecheckIface, typecheckStmt, typecheckExpr,
+ typecheckExtraDecls, typecheckCoreModule,
TcResults(..)
) where
#include "HsVersions.h"
-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 ( TypecheckedMonoBinds,
+import CmdLineOpts ( DynFlag(..), DynFlags, dopt )
+import HsSyn ( HsBinds(..), MonoBinds(..), HsDecl(..), HsExpr(..),
+ Stmt(..), InPat(..), HsMatchContext(..), HsDoContext(..), RuleDecl(..),
+ isSourceInstDecl, mkSimpleMatch, placeHolderType, isCoreDecl
+ )
+import PrelNames ( ioTyConName, printName,
+ returnIOName, bindIOName, failIOName, thenIOName, runMainName,
+ dollarMainName, itName
+ )
+import MkId ( unsafeCoerceId )
+import RnHsSyn ( RenamedHsDecl, RenamedStmt, RenamedHsExpr,
+ RenamedRuleDecl, RenamedTyClDecl, RenamedInstDecl )
+import TcHsSyn ( TypecheckedMonoBinds, TypecheckedHsExpr,
TypecheckedForeignDecl, TypecheckedRuleDecl,
- zonkTopBinds, zonkForeignExports, zonkRules
+ TypecheckedCoreBind,
+ zonkTopBinds, zonkForeignExports, zonkRules, mkHsLet,
+ zonkExpr, zonkIdBndr
)
+import Rename ( RnResult(..) )
+import MkIface ( pprModDetails )
+import TcExpr ( tcMonoExpr )
import TcMonad
-import Inst ( emptyLIE, plusLIE )
+import TcMType ( newTyVarTy, zonkTcType )
+import TcType ( Type, liftedTypeKind, openTypeKind,
+ tyVarsOfType, tcFunResultTy,
+ mkForAllTys, mkFunTys, mkTyConApp, tcSplitForAllTys,
+ tcSplitTyConApp_maybe, isUnitTy
+ )
+import TcMatches ( tcStmtsAndThen )
+import Inst ( LIE, emptyLIE, plusLIE )
import TcBinds ( tcTopBinds )
-import TcClassDcl ( tcClassDecls2, mkImplicitClassBinds )
-import TcDefaults ( tcDefaults )
-import TcEnv ( tcExtendGlobalValEnv, tcLookupGlobal_maybe,
- tcEnvTyCons, tcEnvClasses,
- tcSetEnv, tcSetInstEnv, initEnv
+import TcClassDcl ( tcClassDecls2 )
+import TcDefaults ( tcDefaults, defaultDefaultTys )
+import TcEnv ( TcEnv, RecTcEnv, InstInfo(iDFunId), tcExtendGlobalValEnv,
+ isLocalThing, tcSetEnv, tcSetInstEnv, initTcEnv, getTcGEnv,
+ tcExtendGlobalEnv, tcExtendGlobalTypeEnv,
+ tcLookupGlobalId, tcLookupTyCon,
+ TyThing(..), tcLookupId
)
-import TcRules ( tcRules )
+import TcRules ( tcIfaceRules, tcSourceRules )
import TcForeign ( tcForeignImports, tcForeignExports )
-import TcIfaceSig ( tcInterfaceSigs )
-import TcInstDcls ( tcInstDecls1, tcInstDecls2 )
-import TcInstUtil ( InstInfo )
-import TcSimplify ( tcSimplifyTop )
+import TcIfaceSig ( tcInterfaceSigs, tcCoreBinds )
+import TcInstDcls ( tcInstDecls1, tcIfaceInstDecls1, addInstDFuns, initInstEnv, tcInstDecls2 )
+import TcSimplify ( tcSimplifyTop, tcSimplifyInfer )
import TcTyClsDecls ( tcTyAndClassDecls )
-import TcTyDecls ( mkImplicitDataBinds )
-
import CoreUnfold ( unfoldingTemplate )
-import Type ( funResultTy, splitForAllTys )
-import RnMonad ( RnNameSupply, FixityEnv )
-import Bag ( isEmptyBag )
-import ErrUtils ( printErrorsAndWarnings, dumpIfSet )
-import Id ( idType, idName, idUnfolding )
-import Module ( pprModuleName, mkThisModule, plusModuleEnv )
-import Name ( nameOccName, isLocallyDefined, isGlobalName,
- toRdrName, nameEnvElts,
+import TysWiredIn ( mkListTy, unitTy )
+import ErrUtils ( printErrorsAndWarnings, errorsFound,
+ dumpIfSet_dyn, dumpIfSet_dyn_or, showPass )
+import Rules ( extendRuleBase )
+import Id ( Id, mkLocalId, idType, idUnfolding, setIdLocalExported )
+import Module ( Module )
+import Name ( Name, getName, getSrcLoc )
+import TyCon ( tyConGenInfo )
+import BasicTypes ( EP(..), RecFlag(..) )
+import SrcLoc ( noSrcLoc )
+import Outputable
+import IO ( stdout )
+import HscTypes ( PersistentCompilerState(..), HomeSymbolTable,
+ PackageTypeEnv, ModIface(..),
+ ModDetails(..), DFunId,
+ TypeEnv, extendTypeEnvList, typeEnvTyCons, typeEnvElts,
+ mkTypeEnv
)
-import TyCon ( TyCon, isDataTyCon, tyConName, tyConGenInfo )
-import OccName ( isSysOcc )
-import TyCon ( TyCon, isClassTyCon )
-import Class ( Class )
-import PrelNames ( mAIN_Name, mainKey )
-import UniqSupply ( UniqSupply )
-import Maybes ( maybeToBool )
-import Util
-import BasicTypes ( EP(..) )
-import Bag ( Bag, isEmptyBag )
-vimport Outputable
+import List ( partition )
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The stmt interface}
+%* *
+%************************************************************************
+\begin{code}
+typecheckStmt
+ :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> TypeEnv -- The interactive context's type envt
+ -> PrintUnqualified -- For error printing
+ -> Module -- Is this really needed
+ -> [Name] -- Names bound by the Stmt (empty for expressions)
+ -> (RenamedStmt, -- The stmt itself
+ [RenamedHsDecl]) -- Plus extra decls it sucked in from interface files
+ -> IO (Maybe (PersistentCompilerState,
+ TypecheckedHsExpr,
+ [Id],
+ Type))
+ -- The returned [Id] is the same as the input except for
+ -- ExprStmt, in which case the returned [Name] is [itName]
+
+typecheckStmt dflags pcs hst ic_type_env unqual this_mod names (stmt, iface_decls)
+ = typecheck dflags pcs hst unqual $
+
+ -- use the default default settings, i.e. [Integer, Double]
+ tcSetDefaultTys defaultDefaultTys $
+
+ -- Typecheck the extra declarations
+ tcExtraDecls pcs hst this_mod iface_decls `thenTc` \ (new_pcs, env) ->
+
+ tcSetEnv env $
+ tcExtendGlobalTypeEnv ic_type_env $
+
+ -- The real work is done here
+ tcUserStmt names stmt `thenTc` \ (expr, bound_ids) ->
+
+ traceTc (text "tcs 1") `thenNF_Tc_`
+ zonkExpr expr `thenNF_Tc` \ zonked_expr ->
+ mapNF_Tc zonkIdBndr bound_ids `thenNF_Tc` \ zonked_ids ->
+
+ ioToTc (dumpIfSet_dyn dflags Opt_D_dump_tc "Bound Ids" (vcat (map ppr zonked_ids))) `thenNF_Tc_`
+ 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")
\end{code}
-Outside-world interface:
+Here is the grand plan, implemented in tcUserStmt
+
+ What you type The IO [HValue] that hscStmt returns
+ ------------- ------------------------------------
+ let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
+ bindings: [x,y,...]
+
+ pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
+ bindings: [x,y,...]
+
+ expr (of IO type) ==> expr >>= \ v -> return [v]
+ [NB: result not printed] bindings: [it]
+
+
+ expr (of non-IO type,
+ result showable) ==> let v = expr in print v >> return [v]
+ bindings: [it]
+
+ expr (of non-IO type,
+ result not showable) ==> error
+
+
\begin{code}
+tcUserStmt :: [Name] -> RenamedStmt -> TcM (TypecheckedHsExpr, [Id])
+
+tcUserStmt names (ExprStmt expr _ loc)
+ = ASSERT( null names )
+ tcGetUnique `thenNF_Tc` \ uniq ->
+ let
+ fresh_it = itName uniq
+ the_bind = FunMonoBind fresh_it False
+ [ mkSimpleMatch [] expr placeHolderType loc ] loc
+ in
+ tryTc_ (traceTc (text "tcs 1b") `thenNF_Tc_`
+ tc_stmts [fresh_it] [
+ LetStmt (MonoBind the_bind [] NonRecursive),
+ ExprStmt (HsApp (HsVar printName) (HsVar fresh_it)) placeHolderType loc])
+ ( traceTc (text "tcs 1a") `thenNF_Tc_`
+ tc_stmts [fresh_it] [BindStmt (VarPatIn fresh_it) expr loc])
+
+tcUserStmt names stmt
+ = tc_stmts names [stmt]
+
+
+tc_stmts names stmts
+ = mapNF_Tc tcLookupGlobalId
+ [returnIOName, failIOName, bindIOName, thenIOName] `thenNF_Tc` \ io_ids ->
+ tcLookupTyCon ioTyConName `thenNF_Tc` \ ioTyCon ->
+ newTyVarTy liftedTypeKind `thenNF_Tc` \ res_ty ->
+ let
+ return_id = head io_ids -- Rather gruesome
+
+ io_ty = (\ ty -> mkTyConApp ioTyCon [ty], res_ty)
+
+ -- mk_return builds the expression
+ -- returnIO @ [()] [coerce () x, .., coerce () z]
+ mk_return ids = HsApp (TyApp (HsVar return_id) [mkListTy unitTy])
+ (ExplicitList unitTy (map mk_item ids))
+
+ mk_item id = HsApp (TyApp (HsVar unsafeCoerceId) [idType id, unitTy])
+ (HsVar id)
+ in
+
+ traceTc (text "tcs 2") `thenNF_Tc_`
+ tcStmtsAndThen combine (DoCtxt DoExpr) io_ty stmts (
+ -- Look up the names right in the middle,
+ -- where they will all be in scope
+ mapNF_Tc tcLookupId names `thenNF_Tc` \ ids ->
+ returnTc ((ids, [ResultStmt (mk_return ids) noSrcLoc]), emptyLIE)
+ ) `thenTc` \ ((ids, tc_stmts), lie) ->
+
+ -- Simplify the context right here, so that we fail
+ -- if there aren't enough instances. Notably, when we see
+ -- e
+ -- we use tryTc_ to try it <- e
+ -- and then let it = e
+ -- It's the simplify step that rejects the first.
+
+ traceTc (text "tcs 3") `thenNF_Tc_`
+ tcSimplifyTop lie `thenTc` \ const_binds ->
+ traceTc (text "tcs 4") `thenNF_Tc_`
+
+ returnTc (mkHsLet const_binds $
+ HsDoOut DoExpr tc_stmts io_ids
+ (mkTyConApp ioTyCon [mkListTy unitTy]) noSrcLoc,
+ ids)
+ where
+ combine stmt (ids, stmts) = (ids, stmt:stmts)
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Typechecking an expression}
+%* *
+%************************************************************************
+
+\begin{code}
+typecheckExpr :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> TypeEnv -- The interactive context's type envt
+ -> PrintUnqualified -- For error printing
+ -> Module
+ -> (RenamedHsExpr, -- The expression itself
+ [RenamedHsDecl]) -- Plus extra decls it sucked in from interface files
+ -> IO (Maybe (PersistentCompilerState,
+ TypecheckedHsExpr,
+ [Id], -- always empty (matches typecheckStmt)
+ Type))
+
+typecheckExpr dflags pcs hst ic_type_env unqual this_mod (expr, decls)
+ = typecheck dflags pcs hst unqual $
+
+ -- use the default default settings, i.e. [Integer, Double]
+ tcSetDefaultTys defaultDefaultTys $
+
+ -- Typecheck the extra declarations
+ tcExtraDecls pcs hst this_mod decls `thenTc` \ (new_pcs, env) ->
+
+ -- Now typecheck the expression
+ tcSetEnv env $
+ tcExtendGlobalTypeEnv ic_type_env $
+
+ newTyVarTy openTypeKind `thenTc` \ ty ->
+ tcMonoExpr expr ty `thenTc` \ (e', lie) ->
+ tcSimplifyInfer smpl_doc (tyVarsOfType ty) lie
+ `thenTc` \ (qtvs, lie_free, dict_binds, dict_ids) ->
+ tcSimplifyTop lie_free `thenTc` \ const_binds ->
+
+ let all_expr = mkHsLet const_binds $
+ TyLam qtvs $
+ DictLam dict_ids $
+ mkHsLet dict_binds $
+ e'
+
+ all_expr_ty = mkForAllTys qtvs $
+ mkFunTys (map idType dict_ids) $
+ ty
+ in
+
+ zonkExpr all_expr `thenNF_Tc` \ zonked_expr ->
+ zonkTcType all_expr_ty `thenNF_Tc` \ zonked_ty ->
+ ioToTc (dumpIfSet_dyn dflags
+ Opt_D_dump_tc "Typechecked" (ppr zonked_expr)) `thenNF_Tc_`
+ returnTc (new_pcs, zonked_expr, [], zonked_ty)
+
+ where
+ smpl_doc = ptext SLIT("main expression")
+\end{code}
+
+%************************************************************************
+%* *
+\subsection{Typechecking extra declarations}
+%* *
+%************************************************************************
+
+\begin{code}
+typecheckExtraDecls
+ :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> PrintUnqualified -- For error printing
+ -> Module -- Is this really needed
+ -> [RenamedHsDecl] -- extra decls sucked in from interface files
+ -> IO (Maybe PersistentCompilerState)
+
+typecheckExtraDecls dflags pcs hst unqual this_mod decls
+ = typecheck dflags pcs hst unqual $
+ 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}
+%* *
+%************************************************************************
+
+\begin{code}
+typecheckModule
+ :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> PrintUnqualified -- For error printing
+ -> RnResult
+ -> IO (Maybe (PersistentCompilerState, TcResults))
+ -- The new PCS is Augmented with imported information,
+ -- (but not stuff from this module)
--- Convenient type synonyms first:
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.
+ -- All these fields have info *just for this module*
+ tc_env :: TypeEnv, -- The top level TypeEnv
+ tc_insts :: [DFunId], -- Instances
tc_rules :: [TypecheckedRuleDecl], -- Transformation rules
+ tc_binds :: TypecheckedMonoBinds, -- Bindings
+ tc_fords :: [TypecheckedForeignDecl] -- Foreign import & exports.
}
----------------
-typecheckModule
- :: PersistentCompilerState
- -> HomeSymbolTable
- -> RenamedHsModule
- -> IO (Maybe (PersistentCompilerState, TcResults))
-typecheckModule pcs hst (HsModule mod_name _ _ _ decls _ src_loc)
- = do { env <- initTcEnv global_symbol_table global_inst_env ;
+typecheckModule dflags pcs hst unqual rn_result
+ = do { maybe_tc_result <- typecheck dflags pcs hst unqual $
+ tcModule pcs hst rn_result
+ ; printTcDump dflags unqual maybe_tc_result
+ ; return maybe_tc_result }
+
+tcModule :: PersistentCompilerState
+ -> HomeSymbolTable
+ -> RnResult
+ -> TcM (PersistentCompilerState, TcResults)
+
+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
+ -- recursion, interface type signatures may mention variables defined
+ -- 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 this_mod
+ tycl_decls iface_inst_decls iface_rule_decls `thenTc` \ (env1, new_pcs) ->
+
+ tcSetEnv env1 $
+
+ -- 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 $
- (_, (maybe_result, msgs)) <- initTc env src_loc tc_module
-
- printErrorsAndWarnings msgs ;
+ -- Foreign import declarations next
+ traceTc (text "Tc4") `thenNF_Tc_`
+ tcForeignImports decls `thenTc` \ (fo_ids, foi_decls) ->
+ tcExtendGlobalValEnv fo_ids $
+
+ -- Default declarations
+ tcDefaults decls `thenTc` \ defaulting_tys ->
+ tcSetDefaultTys defaulting_tys $
- printTcDumps maybe_result ;
-
- if isEmptyBag errs then
- return Nothing
- else
- return result
- }
+ -- Value declarations next.
+ -- 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, env2), lie_valdecls) ->
+
+ -- Second pass over class and instance declarations,
+ -- plus rules and foreign exports, to generate bindings
+ 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 $
+ traceTc (text "Tc7") `thenNF_Tc_`
+ tcInstDecls2 inst_info `thenNF_Tc` \ (lie_instdecls, inst_binds) ->
+ traceTc (text "Tc8") `thenNF_Tc_`
+ tcForeignExports this_mod decls `thenTc` \ (lie_fodecls, foe_binds, foe_decls) ->
+ 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 "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
+ -- 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.)
+ --
+ -- Note that we must do this *after* tcCheckMain, because of the
+ -- following bizarre case:
+ -- main = return ()
+ -- Here, we infer main :: forall a. m a, where m is a free
+ -- type variable. tcCheckMain will unify it with IO, and that
+ -- must happen before tcSimplifyTop, since the latter will report
+ -- m as ambiguous
+ let
+ lie_alldecls = lie_valdecls `plusLIE`
+ lie_instdecls `plusLIE`
+ lie_clasdecls `plusLIE`
+ lie_fodecls `plusLIE`
+ lie_rules `plusLIE`
+ lie_main
+ in
+ tcSimplifyTop lie_alldecls `thenTc` \ const_inst_binds ->
+ 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 `AndMonoBinds`
+ main_bind
+ in
+ traceTc (text "Tc7") `thenNF_Tc_`
+ zonkTopBinds all_binds `thenNF_Tc` \ (all_binds', final_env) ->
+ tcSetEnv final_env $
+ -- zonkTopBinds puts all the top-level Ids into the tcGEnv
+ traceTc (text "Tc8") `thenNF_Tc_`
+ zonkForeignExports foe_decls `thenNF_Tc` \ foe_decls' ->
+ traceTc (text "Tc9") `thenNF_Tc_`
+ zonkRules src_rules `thenNF_Tc` \ src_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 = mkTypeEnv src_things,
+ tc_insts = map iDFunId inst_info,
+ tc_binds = all_binds',
+ tc_fords = foi_decls ++ foe_decls',
+ tc_rules = src_rules'
+ }
+ )
+ ) `thenTc` \ (_, pcs, tc_result) ->
+ returnTc (pcs, tc_result)
where
- this_mod = mkThisModule
- global_symbol_table = pcsPST pcs `plusModuleEnv` hst
+ tycl_decls = [d | TyClD d <- decls]
+ rule_decls = [d | RuleD d <- decls]
+ inst_decls = [d | InstD d <- decls]
+ val_decls = [d | ValD d <- decls]
+
+ core_binds = [d | d <- tycl_decls, isCoreDecl d]
- tc_module = fixTc (\ ~(unf_env ,_) -> tcModule pcs hst this_mod decls unf_env)
+ (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}
-The internal monster:
+
+%************************************************************************
+%* *
+\subsection{Typechecking interface decls}
+%* *
+%************************************************************************
+
\begin{code}
-tcModule :: PersistentCompilerState
- -> HomeSymbolTable
- -> Module
- -> [RenamedHsDecl]
- -> TcEnv -- The knot-tied environment
- -> TcM 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 this_mod decls unf_env
- = -- Type-check the type and class decls
- tcTyAndClassDecls unf_env decls `thenTc` \ env ->
- tcSetEnv env $
+typecheckIface
+ :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> ModIface -- Iface for this module (just module & fixities)
+ -> [RenamedHsDecl]
+ -> IO (Maybe (PersistentCompilerState, ModDetails))
+ -- The new PCS is Augmented with imported information,
+ -- (but not stuff from this module).
+
+typecheckIface dflags pcs hst mod_iface decls
+ = do { maybe_tc_stuff <- typecheck dflags pcs hst alwaysQualify $
+ tcIface pcs this_mod decls
+ ; printIfaceDump dflags maybe_tc_stuff
+ ; return maybe_tc_stuff }
+ where
+ 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
- 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
+ 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)
+
+
+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 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
+ -> Module
+ -> [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 (some source, some imported)
+-- interface signatures (checked lazily)
+-- 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 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].
+ --
+ -- unf_env is also used to get the pragama info
+ -- for imported dfuns and default methods
+
+ = checkNoErrsTc $
+ -- tcImports recovers internally, but if anything gave rise to
+ -- an error we'd better stop now, to avoid a cascade
+
+ traceTc (text "Tc1") `thenNF_Tc_`
+ tcTyAndClassDecls this_mod tycl_decls `thenTc` \ tycl_things ->
+ tcExtendGlobalEnv tycl_things $
- -- Typecheck the instance decls, includes deriving
- tcInstDecls1 pcs hst unf_env this_mod
- local_tycons decls `thenTc` \ (pcs_with_insts, inst_env, inst_info, deriv_binds) ->
- tcSetInstEnv inst_env $
-
- -- 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 ->
+ -- 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 $
- -- 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) ->
-
- -- 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 $
-
- -- 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) ->
+ -- 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 ->
- -- 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.)
+ addInstDFuns (pcs_insts pcs) dfuns `thenNF_Tc` \ new_pcs_insts ->
+ tcGetEnv `thenTc` \ unf_env ->
let
- lie_alldecls = lie_valdecls `plusLIE`
- lie_instdecls `plusLIE`
- lie_clasdecls `plusLIE`
- lie_fodecls `plusLIE`
- lie_rules
+ -- 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 = 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
- 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
+ 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
+ add_rule rule_base (IfaceRuleOut id rule) = extendRuleBase rule_base (id, rule)
+\end{code}
+
+\begin{code}
+typecheckCoreModule
+ :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> ModIface -- Iface for this module (just module & fixities)
+ -> [RenamedHsDecl]
+ -> IO (Maybe (PersistentCompilerState, (TypeEnv, [TypecheckedCoreBind], [TypecheckedRuleDecl])))
+typecheckCoreModule dflags pcs hst mod_iface decls
+ = do { maybe_tc_stuff <- typecheck dflags pcs hst alwaysQualify $
+ tcCoreDecls this_mod decls
+
+-- ; printIfaceDump dflags maybe_tc_stuff
+
+ -- Q: Is it OK not to extend PCS here?
+ -- (in the event that it needs to be, I'm returning the PCS passed in.)
+ ; case maybe_tc_stuff of
+ Nothing -> return Nothing
+ Just result -> return (Just (pcs, result)) }
+ where
+ this_mod = mi_module mod_iface
+ core_decls = [d | (TyClD d) <- decls, isCoreDecl d]
+
+
+tcCoreDecls :: Module
+ -> [RenamedHsDecl] -- All interface-file decls
+ -> TcM (TypeEnv, [TypecheckedCoreBind], [TypecheckedRuleDecl])
+tcCoreDecls this_mod decls
+-- The decls are all TyClD declarations coming from External Core input.
+ = let
+ tycl_decls = [d | TyClD d <- decls]
+ rule_decls = [d | RuleD d <- decls]
+ core_decls = filter isCoreDecl tycl_decls
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 (tcGEnv final_env))
-
- local_type_env :: TypeEnv
- local_type_env = lookupWithDefaultFM groups this_mod emptyNameEnv
-
- new_pst :: PackageSymbolTable
- new_pst = extendTypeEnv (pcsPST pcs) (delFromFM groups this_mod)
-
- final_pcs :: PersistentCompilerState
- final_pcs = pcs_with_insts {pcsPST = new_pst}
- in
- returnTc (really_final_env,
- TcResults { tc_pcs = final_pcs,
- tc_env = local_type_env,
- tc_binds = all_binds',
- tc_insts = map instInfoDfunId inst_infos,
- tc_fords = foi_decls ++ foe_decls',
- tc_rules = rules'
- }))
-
-get_binds decls = foldr ThenBinds EmptyBinds [binds | ValD binds <- decls]
+ fixTc (\ ~(unf_env, _) ->
+ -- This fixTc follows the same general plan as tcImports,
+ -- which is better commented.
+ -- [ Q: do we need to tie a knot for External Core? ]
+ tcTyAndClassDecls this_mod tycl_decls `thenTc` \ tycl_things ->
+ tcExtendGlobalEnv tycl_things $
+
+ tcInterfaceSigs unf_env this_mod tycl_decls `thenTc` \ sig_ids ->
+ tcExtendGlobalValEnv sig_ids $
+
+ tcCoreBinds core_decls `thenTc` \ core_prs ->
+ let
+ local_ids = map fst core_prs
+ in
+ tcExtendGlobalValEnv local_ids $
+
+ tcIfaceRules rule_decls `thenTc` \ rules ->
+
+ let
+ src_things = filter (isLocalThing this_mod) tycl_things
+ ++ map AnId local_ids
+ in
+ tcGetEnv `thenNF_Tc` \ env ->
+ returnTc (env, (mkTypeEnv src_things, core_prs, rules))
+ ) `thenTc` \ (_, result) ->
+ returnTc result
\end{code}
+%************************************************************************
+%* *
+\subsection{Checking the type of main}
+%* *
+%************************************************************************
+
+We must check that in module Main,
+ a) Main.main is in scope
+ b) Main.main :: forall a1...an. IO t, for some type t
+
+Then we build
+ $main = PrelTopHandler.runMain Main.main
+
+The function
+ PrelTopHandler :: IO a -> IO ()
+catches the top level exceptions.
+It accepts a Main.main of any type (IO a).
+
\begin{code}
-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
-
- | otherwise = returnTc ()
-
-noMainErr
- = hsep [ptext SLIT("Module"), quotes (pprModuleName mAIN_Name),
- ptext SLIT("must include a definition for"), quotes (ptext SLIT("main"))]
+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
+ 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}
%************************************************************************
%* *
-\subsection{Dumping output}
+\subsection{Interfacing the Tc monad to the IO monad}
%* *
%************************************************************************
\begin{code}
-printTcDump Nothing = return ()
-printTcDump (Just results)
- = do { dumpIfSet opt_D_dump_types "Type signatures" (dump_sigs results) ;
- dumpIfSet opt_D_dump_tc "Typechecked" (dump_tc results)
- }
+typecheck :: DynFlags
+ -> PersistentCompilerState
+ -> HomeSymbolTable
+ -> PrintUnqualified -- For error printing
+ -> TcM r
+ -> IO (Maybe r)
+
+typecheck dflags pcs hst unqual thing_inside
+ = do { showPass dflags "Typechecker";
+ ; env <- initTcEnv hst (pcs_PTE pcs)
+
+ ; (maybe_tc_result, errs) <- initTc dflags env thing_inside
+
+ ; printErrorsAndWarnings unqual errs
+
+ ; if errorsFound errs then
+ return Nothing
+ else
+ return maybe_tc_result
+ }
+\end{code}
-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)) | id <- nameEnvElts (tc_env results),
- want_sig id
+%************************************************************************
+%* *
+\subsection{Dumping output}
+%* *
+%************************************************************************
+
+\begin{code}
+printTcDump dflags unqual Nothing = return ()
+printTcDump dflags unqual (Just (_, results))
+ = do if dopt Opt_D_dump_types dflags || dopt Opt_D_dump_tc dflags then
+ printForUser stdout unqual (dump_tc_iface dflags results)
+ else return ()
+
+ dumpIfSet_dyn dflags Opt_D_dump_tc
+ -- foreign x-d's have undefined's in their types; hence can't show the tc_fords
+ "Typechecked" (ppr (tc_binds results) {- $$ ppr (tc_fords results)-})
+
+
+printIfaceDump dflags Nothing = return ()
+printIfaceDump dflags (Just (_, details))
+ = dumpIfSet_dyn_or dflags [Opt_D_dump_types, Opt_D_dump_tc]
+ "Interface" (pprModDetails details)
+
+dump_tc_iface dflags results
+ = vcat [pprModDetails (ModDetails {md_types = tc_env results,
+ md_insts = tc_insts results,
+ md_rules = [], md_binds = []}) ,
+ ppr_rules (tc_rules results),
+
+ if dopt Opt_Generics dflags then
+ ppr_gen_tycons (typeEnvTyCons (tc_env results))
+ else
+ empty
]
- 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_rules [] = empty
+ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
+ nest 4 (vcat (map ppr rs)),
+ ptext SLIT("#-}")]
ppr_gen_tycons tcs = vcat [ptext SLIT("{-# Generic type constructor details"),
- vcat (map ppr_gen_tycon (filter isLocallyDefined tcs)),
+ vcat (map ppr_gen_tycon tcs),
ptext SLIT("#-}")
]
| otherwise = ppr tycon <> colon <+> ptext SLIT("Not derivable")
ppr_ep (EP from to)
- = vcat [ ptext SLIT("Rep type:") <+> ppr (funResultTy from_tau),
+ = vcat [ ptext SLIT("Rep type:") <+> ppr (tcFunResultTy 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("#-}")]
+ (_,from_tau) = tcSplitForAllTys (idType from)
\end{code}
projects / ghc-hetmet.git / blobdiff