+++ /dev/null
-%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
-%
-\section[TcModule]{Typechecking a whole module}
-
-\begin{code}
-module TcModule (
- typecheckModule, typecheckIface, typecheckStmt, typecheckExpr,
- typecheckExtraDecls, typecheckCoreModule,
- TcResults(..)
- ) where
-
-#include "HsVersions.h"
-
-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, runIOName,
- dollarMainName, itName
- )
-import MkId ( unsafeCoerceId )
-import RnHsSyn ( RenamedHsDecl, RenamedStmt, RenamedHsExpr,
- RenamedRuleDecl, RenamedTyClDecl, RenamedInstDecl )
-import TcHsSyn ( TypecheckedMonoBinds, TypecheckedHsExpr,
- TypecheckedForeignDecl, TypecheckedRuleDecl,
- TypecheckedCoreBind,
- zonkTopBinds, zonkForeignExports, zonkRules, mkHsLet,
- zonkExpr, zonkIdBndr
- )
-
-import Rename ( RnResult(..) )
-import MkIface ( pprModDetails )
-import TcExpr ( tcMonoExpr )
-import TcMonad
-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 )
-import TcDefaults ( tcDefaults, defaultDefaultTys )
-import TcEnv ( TcEnv, RecTcEnv, InstInfo(iDFunId), tcExtendGlobalValEnv,
- isLocalThing, tcSetEnv, tcSetInstEnv, initTcEnv, getTcGEnv,
- tcExtendGlobalEnv, tcExtendGlobalTypeEnv,
- tcLookupGlobalId, tcLookupTyCon,
- TyThing(..), tcLookupId
- )
-import TcRules ( tcIfaceRules, tcSourceRules )
-import TcForeign ( tcForeignImports, tcForeignExports )
-import TcIfaceSig ( tcInterfaceSigs, tcCoreBinds )
-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 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 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}
-
-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 $
- HsDo 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)
-
-data TcResults
- = TcResults {
- -- 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 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 $
-
- -- 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 $
-
- -- 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
- 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]
-
- (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}
-
-
-%************************************************************************
-%* *
-\subsection{Typechecking interface decls}
-%* *
-%************************************************************************
-
-\begin{code}
-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
- 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 $
-
- -- 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 ->
-
- addInstDFuns (pcs_insts pcs) dfuns `thenNF_Tc` \ new_pcs_insts ->
- tcGetEnv `thenTc` \ unf_env ->
- let
- -- 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
- 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
- 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 = GHC.TopHandler.runIO Main.main
-
-The function
- GHC.TopHandler.runIO :: IO a -> IO a
-catches the top level exceptions.
-It accepts a Main.main of any type (IO a).
-
-\begin{code}
-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 ty )
- let
- dollar_main_id = setIdLocalExported (mkLocalId dollarMainName ty)
- in
- returnTc (VarMonoBind dollar_main_id main_expr, lie)
- where
- rhs = HsApp (HsVar runIOName) (HsVar main_name)
-
-is_io :: Type -> Bool -- True for IO a
-is_io tau = case tcSplitTyConApp_maybe tau of
- Just (tc, [_]) -> getName tc == ioTyConName
- other -> False
-
-mainCtxt = ptext SLIT("When checking the type of 'main'")
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Interfacing the Tc monad to the IO monad}
-%* *
-%************************************************************************
-
-\begin{code}
-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}
-
-
-%************************************************************************
-%* *
-\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) {- $$ ppr (tc_fords results)-})
-
-
-printIfaceDump dflags Nothing = return ()
-printIfaceDump dflags (Just (_, details))
- = dumpIfSet_dyn_or dflags [Opt_D_dump_types, Opt_D_dump_tc]
- "Interface" (pprModDetails details)
-
-dump_tc_iface dflags results
- = vcat [pprModDetails (ModDetails {md_types = tc_env results,
- md_insts = tc_insts results,
- md_rules = [], md_binds = []}) ,
- ppr_rules (tc_rules results),
-
- if dopt Opt_Generics dflags then
- ppr_gen_tycons (typeEnvTyCons (tc_env results))
- else
- empty
- ]
-
-ppr_rules [] = empty
-ppr_rules rs = vcat [ptext SLIT("{-# RULES"),
- nest 4 (vcat (map ppr rs)),
- ptext SLIT("#-}")]
-
-ppr_gen_tycons tcs = vcat [ptext SLIT("{-# Generic type constructor details"),
- vcat (map ppr_gen_tycon tcs),
- ptext SLIT("#-}")
- ]
-
--- x&y are now Id's, not CoreExpr's
-ppr_gen_tycon tycon
- | Just ep <- tyConGenInfo tycon
- = (ppr tycon <> colon) $$ nest 4 (ppr_ep ep)
-
- | otherwise = ppr tycon <> colon <+> ptext SLIT("Not derivable")
-
-ppr_ep (EP from to)
- = vcat [ ptext SLIT("Rep type:") <+> ppr (tcFunResultTy from_tau),
- ptext SLIT("From:") <+> ppr (unfoldingTemplate (idUnfolding from)),
- ptext SLIT("To:") <+> ppr (unfoldingTemplate (idUnfolding to))
- ]
- where
- (_,from_tau) = tcSplitForAllTys (idType from)
-\end{code}
projects / ghc-hetmet.git / blobdiff