GlobalRdrEnv, LocalRdrEnv, NameCache, FixityEnv,
GhciMode, lookupType, unQualInScope )
import TcRnTypes
-import Module ( Module, foldModuleEnv )
+import Module ( Module, unitModuleEnv, foldModuleEnv )
import Name ( Name, isInternalName )
import Type ( Type )
import NameEnv ( extendNameEnvList )
import CmdLineOpts ( DynFlags, DynFlag(..), dopt, opt_PprStyle_Debug )
import BasicTypes ( FixitySig )
import Bag ( snocBag, unionBags )
-
+import Panic ( showException )
+
import Maybe ( isJust )
import IO ( stderr )
import DATA_IOREF ( newIORef, readIORef )
+import EXCEPTION ( Exception )
\end{code}
%************************************************************************
usg_var <- newIORef emptyUsages ;
nc_var <- newIORef (pcs_nc pcs) ;
eps_var <- newIORef eps ;
-
+ ie_var <- newIORef (mkImpInstEnv dflags eps hpt) ;
+
let {
env = Env { env_top = top_env,
env_gbl = gbl_env,
tcg_fix_env = emptyFixityEnv,
tcg_default = defaultDefaultTys,
tcg_type_env = emptyNameEnv,
- tcg_ist = mkImpTypeEnv eps hpt,
- tcg_inst_env = mkImpInstEnv dflags eps hpt,
+ tcg_inst_env = ie_var,
tcg_exports = [],
- tcg_imports = emptyImportAvails,
+ tcg_imports = init_imports,
tcg_binds = EmptyMonoBinds,
tcg_deprecs = NoDeprecs,
tcg_insts = [],
tcg_fords = [] } ;
lcl_env = TcLclEnv {
- tcl_ctxt = [],
- tcl_level = topStage,
- tcl_env = emptyNameEnv,
- tcl_tyvars = tvs_var,
- tcl_lie = panic "initTc:LIE" } ;
+ tcl_ctxt = [],
+ tcl_th_ctxt = topStage,
+ tcl_arrow_ctxt = topArrowCtxt,
+ tcl_env = emptyNameEnv,
+ tcl_tyvars = tvs_var,
+ tcl_lie = panic "initTc:LIE" } ;
-- LIE only valid inside a getLIE
} ;
eps' <- readIORef eps_var ;
nc' <- readIORef nc_var ;
let { pcs' = PCS { pcs_EPS = eps', pcs_nc = nc' } ;
- final_res | errorsFound msgs = Nothing
- | otherwise = maybe_res } ;
+ final_res | errorsFound dflags msgs = Nothing
+ | otherwise = maybe_res } ;
return (pcs', final_res)
}
where
eps = pcs_EPS pcs
+ init_imports = emptyImportAvails { imp_qual = unitModuleEnv mod emptyAvailEnv }
+ -- Initialise tcg_imports with an empty set of bindings for
+ -- this module, so that if we see 'module M' in the export
+ -- list, and there are no bindings in M, we don't bleat
+ -- "unknown module M".
+
defaultDefaultTys :: [Type]
defaultDefaultTys = [integerTy, doubleTy]
mkImpInstEnv :: DynFlags -> ExternalPackageState -> HomePackageTable -> InstEnv
+-- At the moment we (wrongly) build an instance environment from all the
+-- modules we have already compiled:
+-- (a) eps_inst_env from the external package state
+-- (b) all the md_insts in the home package table
+-- We should really only get instances from modules below us in the
+-- module import tree.
mkImpInstEnv dflags eps hpt
= foldModuleEnv (add . md_insts . hm_details)
(eps_inst_env eps)
where
-- We shouldn't get instance conflict errors from
-- the package and home type envs
- add dfuns inst_env = WARN( not (null errs), vcat errs ) inst_env'
+ add dfuns inst_env = WARN( not (null errs), vcat (map snd errs) ) inst_env'
where
(inst_env', errs) = extendInstEnv dflags inst_env dfuns
setLclEnv :: m -> TcRn m a -> TcRn n a
setLclEnv lcl_env = updEnv (\ env -> env { env_lcl = lcl_env })
+
+getEnvs :: TcRn m (TcGblEnv, m)
+getEnvs = do { env <- getEnv; return (env_gbl env, env_lcl env) }
+
+setEnvs :: (TcGblEnv, m) -> TcRn m a -> TcRn m a
+setEnvs (gbl_env, lcl_env) = updEnv (\ env -> env { env_gbl = gbl_env, env_lcl = lcl_env })
\end{code}
+
Command-line flags
\begin{code}
getGlobalRdrEnv :: TcRn m GlobalRdrEnv
getGlobalRdrEnv = do { env <- getGblEnv; return (tcg_rdr_env env) }
+getImports :: TcRn m ImportAvails
+getImports = do { env <- getGblEnv; return (tcg_imports env) }
+
getFixityEnv :: TcRn m FixityEnv
getFixityEnv = do { env <- getGblEnv; return (tcg_fix_env env) }
\end{code}
\begin{code}
-getUsageVar :: TcRn m (TcRef Usages)
+getUsageVar :: TcRn m (TcRef EntityUsage)
getUsageVar = do { env <- getGblEnv; return (tcg_usages env) }
-getUsages :: TcRn m Usages
+getUsages :: TcRn m EntityUsage
getUsages = do { usg_var <- getUsageVar; readMutVar usg_var }
-updUsages :: (Usages -> Usages) -> TcRn m ()
+updUsages :: (EntityUsage -> EntityUsage) -> TcRn m ()
updUsages upd = do { usg_var <- getUsageVar ;
usg <- readMutVar usg_var ;
writeMutVar usg_var (upd usg) }
env { env_top = top_env { top_errs = v }})
addErr :: Message -> TcRn m ()
-addErr msg = do { loc <- getSrcLocM ; add_err loc msg }
+addErr msg = do { loc <- getSrcLocM ; addErrAt loc msg }
-add_err :: SrcLoc -> Message -> TcRn m ()
-add_err loc msg
+addErrAt :: SrcLoc -> Message -> TcRn m ()
+addErrAt loc msg
= do { errs_var <- getErrsVar ;
rdr_env <- getGlobalRdrEnv ;
let { err = addShortErrLocLine loc (unQualInScope rdr_env) msg } ;
(warns, errs) <- readMutVar errs_var ;
writeMutVar errs_var (warns, errs `snocBag` err) }
-addErrs :: [Message] -> TcRn m ()
-addErrs msgs = mappM_ addErr msgs
+addErrs :: [(SrcLoc,Message)] -> TcRn m ()
+addErrs msgs = mappM_ add msgs
+ where
+ add (loc,msg) = addErrAt loc msg
addWarn :: Message -> TcRn m ()
addWarn msg
(warns, errs) <- readMutVar errs_var ;
writeMutVar errs_var (warns `unionBags` m_warns,
errs `unionBags` m_errs) }
-
-checkGHCI :: Message -> TcRn m () -- Check that GHCI is on
- -- otherwise add the error message
-#ifdef GHCI
-checkGHCI m = returnM ()
-#else
-checkGHCI m = addErr m
-#endif
\end{code}
\begin{code}
-tryM :: TcRn m a -> TcRn m (Messages, Maybe a)
- -- (try m) executes m, and returns
+recoverM :: TcRn m r -- Recovery action; do this if the main one fails
+ -> TcRn m r -- Main action: do this first
+ -> TcRn m r
+recoverM recover thing
+ = do { mb_res <- try_m thing ;
+ case mb_res of
+ Left exn -> recover
+ Right res -> returnM res }
+
+tryTc :: TcRn m a -> TcRn m (Messages, Maybe a)
+ -- (tryTc m) executes m, and returns
-- Just r, if m succeeds (returning r) and caused no errors
-- Nothing, if m fails, or caused errors
-- It also returns all the errors accumulated by m
-- (even in the Just case, there might be warnings)
--
-- It always succeeds (never raises an exception)
-tryM m
+tryTc m
= do { errs_var <- newMutVar emptyMessages ;
- mb_r <- recoverM (return Nothing)
- (do { r <- setErrsVar errs_var m ;
- return (Just r) }) ;
+ mb_r <- try_m (setErrsVar errs_var m) ;
new_errs <- readMutVar errs_var ;
+ dflags <- getDOpts ;
+
return (new_errs,
case mb_r of
- Nothing -> Nothing
- Just r | errorsFound new_errs -> Nothing
- | otherwise -> Just r)
+ Left exn -> Nothing
+ Right r | errorsFound dflags new_errs -> Nothing
+ | otherwise -> Just r)
}
-tryTc :: TcM a -> TcM (Messages, Maybe a)
--- Just like tryM, except that it ensures that the LIE
+try_m :: TcRn m r -> TcRn m (Either Exception r)
+-- Does try_m, with a debug-trace on failure
+try_m thing
+ = do { mb_r <- tryM thing ;
+ case mb_r of
+ Left exn -> do { traceTc (exn_msg exn); return mb_r }
+ Right r -> return mb_r }
+ where
+ exn_msg exn = text "recoverM recovering from" <+> text (showException exn)
+
+tryTcLIE :: TcM a -> TcM (Messages, Maybe a)
+-- Just like tryTc, except that it ensures that the LIE
-- for the thing is propagated only if there are no errors
-- Hence it's restricted to the type-check monad
-tryTc thing_inside
- = do { ((errs, mb_r), lie) <- getLIE (tryM thing_inside) ;
+tryTcLIE thing_inside
+ = do { ((errs, mb_r), lie) <- getLIE (tryTc thing_inside) ;
ifM (isJust mb_r) (extendLIEs lie) ;
return (errs, mb_r) }
-tryTc_ :: TcM r -> TcM r -> TcM r
--- (tryM_ r m) tries m; if it succeeds it returns it,
+tryTcLIE_ :: TcM r -> TcM r -> TcM r
+-- (tryTcLIE_ r m) tries m; if it succeeds it returns it,
-- otherwise it returns r. Any error messages added by m are discarded,
-- whether or not m succeeds.
-tryTc_ recover main
- = do { (_msgs, mb_res) <- tryTc main ;
+tryTcLIE_ recover main
+ = do { (_msgs, mb_res) <- tryTcLIE main ;
case mb_res of
Just res -> return res
Nothing -> recover }
-- If so, it fails too.
-- Regardless, any errors generated by m are propagated to the enclosing context.
checkNoErrs main
- = do { (msgs, mb_res) <- tryTc main ;
+ = do { (msgs, mb_res) <- tryTcLIE main ;
addMessages msgs ;
case mb_res of
Just r -> return r
ifErrsM bale_out normal
= do { errs_var <- getErrsVar ;
msgs <- readMutVar errs_var ;
- if errorsFound msgs then
+ dflags <- getDOpts ;
+ if errorsFound dflags msgs then
bale_out
else
normal }
-- Run thing_inside in an interleaved thread. It gets a separate
-- * errs_var, and
-- * unique supply,
+-- * LIE var is set to bottom (should never be used)
-- but everything else is shared, so this is DANGEROUS.
--
-- It returns Nothing if the computation fails
= do { us <- newUniqueSupply ;
unsafeInterleaveM $
do { us_var <- newMutVar us ;
- (msgs, mb_res) <- tryTc (setUsVar us_var thing_inside) ;
+ (msgs, mb_res) <- tryTc (setLIEVar (panic "forkM: LIE used") $
+ setUsVar us_var thing_inside) ;
case mb_res of
Just r -> return (Just r)
Nothing -> do {
- -- Bleat about errors in the forked thread
- ioToTcRn (do { printErrs (hdr_doc defaultErrStyle) ;
- printErrorsAndWarnings msgs }) ;
+
+ -- Bleat about errors in the forked thread, if -ddump-tc-trace is on
+ -- Otherwise we silently discard errors. Errors can legitimately
+ -- happen when compiling interface signatures (see tcInterfaceSigs)
+ ifOptM Opt_D_dump_tc_trace
+ (ioToTcRn (do { printErrs (hdr_doc defaultErrStyle) ;
+ printErrorsAndWarnings msgs })) ;
+
return Nothing }
}}
where
traceTc, traceRn :: SDoc -> TcRn a ()
traceRn = dumpOptTcRn Opt_D_dump_rn_trace
traceTc = dumpOptTcRn Opt_D_dump_tc_trace
+traceSplice = dumpOptTcRn Opt_D_dump_splices
traceHiDiffs = dumpOptTcRn Opt_D_dump_hi_diffs
dumpOptTcRn :: DynFlag -> SDoc -> TcRn a ()
getInstLoc :: InstOrigin -> TcM InstLoc
getInstLoc origin
= do { loc <- getSrcLocM ; env <- getLclEnv ;
- return (origin, loc, (tcl_ctxt env)) }
+ return (InstLoc origin loc (tcl_ctxt env)) }
+
+addInstCtxt :: InstLoc -> TcM a -> TcM a
+-- Add the SrcLoc and context from the first Inst in the list
+-- (they all have similar locations)
+addInstCtxt (InstLoc _ src_loc ctxt) thing_inside
+ = addSrcLoc src_loc (updCtxt (\ old_ctxt -> ctxt) thing_inside)
\end{code}
- The addErr functions add an error message, but do not cause failure.
+ The addErrTc functions add an error message, but do not cause failure.
The 'M' variants pass a TidyEnv that has already been used to
tidy up the message; we then use it to tidy the context messages
= do { ctxt <- getErrCtxt ;
loc <- getSrcLocM ;
add_err_tcm tidy_env err_msg loc ctxt }
-
-addInstErrTcM :: InstLoc -> (TidyEnv, Message) -> TcM ()
-addInstErrTcM inst_loc@(_, loc, ctxt) (tidy_env, err_msg)
- = add_err_tcm tidy_env err_msg loc full_ctxt
- where
- full_ctxt = (\env -> returnM (env, pprInstLoc inst_loc)) : ctxt
\end{code}
The failWith functions add an error message and cause failure
\begin{code}
add_err_tcm tidy_env err_msg loc ctxt
= do { ctxt_msgs <- do_ctxt tidy_env ctxt ;
- add_err loc (vcat (err_msg : ctxt_to_use ctxt_msgs)) }
+ addErrAt loc (vcat (err_msg : ctxt_to_use ctxt_msgs)) }
do_ctxt tidy_env []
= return []
%************************************************************************
%* *
- Other stuff specific to type checker
+ Type constraints (the so-called LIE)
%* *
%************************************************************************
writeMutVar lie_var (mkLIE insts `plusLIE` lie) }
\end{code}
-
\begin{code}
-getStage :: TcM Stage
-getStage = do { env <- getLclEnv; return (tcl_level env) }
-
-setStage :: Stage -> TcM a -> TcM a
-setStage s = updLclEnv (\ env -> env { tcl_level = s })
-
setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a
-- Set the local type envt, but do *not* disturb other fields,
-- notably the lie_var
%************************************************************************
%* *
+ Template Haskell context
+%* *
+%************************************************************************
+
+\begin{code}
+getStage :: TcM ThStage
+getStage = do { env <- getLclEnv; return (tcl_th_ctxt env) }
+
+setStage :: ThStage -> TcM a -> TcM a
+setStage s = updLclEnv (\ env -> env { tcl_th_ctxt = s })
+\end{code}
+
+
+%************************************************************************
+%* *
+ Arrow context
+%* *
+%************************************************************************
+
+\begin{code}
+popArrowBinders :: TcM a -> TcM a -- Move to the left of a (-<); see comments in TcRnTypes
+popArrowBinders
+ = updLclEnv (\ env -> env { tcl_arrow_ctxt = pop (tcl_arrow_ctxt env) })
+ where
+ pop (ArrCtxt {proc_level = curr_lvl, proc_banned = banned})
+ = ASSERT( not (curr_lvl `elem` banned) )
+ ArrCtxt {proc_level = curr_lvl, proc_banned = curr_lvl : banned}
+
+getBannedProcLevels :: TcM [ProcLevel]
+ = do { env <- getLclEnv; return (proc_banned (tcl_arrow_ctxt env)) }
+
+incProcLevel :: TcM a -> TcM a
+incProcLevel
+ = updLclEnv (\ env -> env { tcl_arrow_ctxt = inc (tcl_arrow_ctxt env) })
+ where
+ inc ctxt = ctxt { proc_level = proc_level ctxt + 1 }
+\end{code}
+
+
+%************************************************************************
+%* *
Stuff for the renamer's local env
%* *
%************************************************************************
\begin{code}
initRn :: RnMode -> RnM a -> TcRn m a
initRn mode thing_inside
- = do { env <- getGblEnv ;
- let { lcl_env = RnLclEnv {
+ = do { let { lcl_env = RnLclEnv {
rn_mode = mode,
rn_lenv = emptyRdrEnv }} ;
setLclEnv lcl_env thing_inside }