%
\begin{code}
-{-# OPTIONS -w #-}
--- The above warning supression flag is a temporary kludge.
--- While working on this module you are encouraged to remove it and fix
--- any warnings in the module. See
--- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
--- for details
-
module TcRnMonad(
module TcRnMonad,
module TcRnTypes,
import TcType
import InstEnv
import FamInstEnv
+import PrelNames ( iNTERACTIVE )
-import Coercion
import Var
import Id
import VarSet
import SrcLoc
import NameEnv
import NameSet
-import OccName
import Bag
import Outputable
import UniqSupply
import StaticFlags
import FastString
import Panic
-
+import Util
+
import System.IO
import Data.IORef
-import Control.Exception
+import qualified Data.Set as Set
+import Control.Monad
\end{code}
%************************************************************************
\begin{code}
-ioToTcRn :: IO r -> TcRn r
-ioToTcRn = ioToIOEnv
-\end{code}
-
-\begin{code}
initTc :: HscEnv
-> HscSource
initTc hsc_env hsc_src keep_rn_syntax mod do_this
= do { errs_var <- newIORef (emptyBag, emptyBag) ;
+ meta_var <- newIORef initTyVarUnique ;
tvs_var <- newIORef emptyVarSet ;
- type_env_var <- newIORef emptyNameEnv ;
- dfuns_var <- newIORef emptyNameSet ;
- keep_var <- newIORef emptyNameSet ;
+ keep_var <- newIORef emptyNameSet ;
+ used_rdr_var <- newIORef Set.empty ;
th_var <- newIORef False ;
- dfun_n_var <- newIORef 1 ;
+ lie_var <- newIORef emptyWC ;
+ dfun_n_var <- newIORef emptyOccSet ;
+ type_env_var <- case hsc_type_env_var hsc_env of {
+ Just (_mod, te_var) -> return te_var ;
+ Nothing -> newIORef emptyNameEnv } ;
let {
- maybe_rn_syntax empty_val
+ maybe_rn_syntax :: forall a. a -> Maybe a ;
+ maybe_rn_syntax empty_val
| keep_rn_syntax = Just empty_val
| otherwise = Nothing ;
gbl_env = TcGblEnv {
tcg_mod = mod,
tcg_src = hsc_src,
- tcg_rdr_env = hsc_global_rdr_env hsc_env,
+ tcg_rdr_env = emptyGlobalRdrEnv,
tcg_fix_env = emptyNameEnv,
- tcg_field_env = emptyNameEnv,
+ tcg_field_env = RecFields emptyNameEnv emptyNameSet,
tcg_default = Nothing,
- tcg_type_env = hsc_global_type_env hsc_env,
+ tcg_type_env = emptyNameEnv,
tcg_type_env_var = type_env_var,
tcg_inst_env = emptyInstEnv,
tcg_fam_inst_env = emptyFamInstEnv,
- tcg_inst_uses = dfuns_var,
- tcg_th_used = th_var,
+ tcg_th_used = th_var,
tcg_exports = [],
tcg_imports = emptyImportAvails,
+ tcg_used_rdrnames = used_rdr_var,
tcg_dus = emptyDUs,
- tcg_rn_imports = maybe_rn_syntax [],
+ tcg_rn_imports = [],
tcg_rn_exports = maybe_rn_syntax [],
tcg_rn_decls = maybe_rn_syntax emptyRnGroup,
- tcg_binds = emptyLHsBinds,
- tcg_deprecs = NoDeprecs,
- tcg_insts = [],
- tcg_fam_insts= [],
- tcg_rules = [],
- tcg_fords = [],
- tcg_dfun_n = dfun_n_var,
- tcg_keep = keep_var,
- tcg_doc = Nothing,
- tcg_hmi = HaddockModInfo Nothing Nothing Nothing Nothing,
- tcg_hpc = False
+ tcg_binds = emptyLHsBinds,
+ tcg_imp_specs = [],
+ tcg_sigs = emptyNameSet,
+ tcg_ev_binds = emptyBag,
+ tcg_warns = NoWarnings,
+ tcg_anns = [],
+ tcg_insts = [],
+ tcg_fam_insts = [],
+ tcg_rules = [],
+ tcg_fords = [],
+ tcg_vects = [],
+ tcg_dfun_n = dfun_n_var,
+ tcg_keep = keep_var,
+ tcg_doc_hdr = Nothing,
+ tcg_hpc = False,
+ tcg_main = Nothing
} ;
lcl_env = TcLclEnv {
tcl_errs = errs_var,
- tcl_loc = mkGeneralSrcSpan FSLIT("Top level"),
+ tcl_loc = mkGeneralSrcSpan (fsLit "Top level"),
tcl_ctxt = [],
tcl_rdr = emptyLocalRdrEnv,
tcl_th_ctxt = topStage,
tcl_arrow_ctxt = NoArrowCtxt,
tcl_env = emptyNameEnv,
tcl_tyvars = tvs_var,
- tcl_lie = panic "initTc:LIE" -- LIE only valid inside a getLIE
+ tcl_lie = lie_var,
+ tcl_meta = meta_var,
+ tcl_untch = initTyVarUnique
} ;
} ;
Right res -> return (Just res)
Left _ -> return Nothing } ;
+ -- Check for unsolved constraints
+ lie <- readIORef lie_var ;
+ if isEmptyWC lie
+ then return ()
+ else pprPanic "initTc: unsolved constraints"
+ (pprWantedsWithLocs lie) ;
+
-- Collect any error messages
msgs <- readIORef errs_var ;
:: HscEnv
-> Module
-> TcM r
- -> IO (Maybe r)
-initTcPrintErrors env mod todo = do
- (msgs, res) <- initTc env HsSrcFile False mod todo
- printErrorsAndWarnings (hsc_dflags env) msgs
- return res
+ -> IO (Messages, Maybe r)
+
+initTcPrintErrors env mod todo = initTc env HsSrcFile False mod todo
\end{code}
%************************************************************************
getDOpts :: TcRnIf gbl lcl DynFlags
getDOpts = do { env <- getTopEnv; return (hsc_dflags env) }
+xoptM :: ExtensionFlag -> TcRnIf gbl lcl Bool
+xoptM flag = do { dflags <- getDOpts; return (xopt flag dflags) }
+
doptM :: DynFlag -> TcRnIf gbl lcl Bool
doptM flag = do { dflags <- getDOpts; return (dopt flag dflags) }
-setOptM :: DynFlag -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a
+-- XXX setOptM and unsetOptM operate on different types. One should be renamed.
+
+setOptM :: ExtensionFlag -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a
setOptM flag = updEnv (\ env@(Env { env_top = top }) ->
- env { env_top = top { hsc_dflags = dopt_set (hsc_dflags top) flag}} )
+ env { env_top = top { hsc_dflags = xopt_set (hsc_dflags top) flag}} )
unsetOptM :: DynFlag -> TcRnIf gbl lcl a -> TcRnIf gbl lcl a
unsetOptM flag = updEnv (\ env@(Env { env_top = top }) ->
env { env_top = top { hsc_dflags = dopt_unset (hsc_dflags top) flag}} )
-ifOptM :: DynFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl () -- Do it flag is true
-ifOptM flag thing_inside = do { b <- doptM flag;
+-- | Do it flag is true
+ifDOptM :: DynFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()
+ifDOptM flag thing_inside = do { b <- doptM flag;
+ if b then thing_inside else return () }
+
+ifXOptM :: ExtensionFlag -> TcRnIf gbl lcl () -> TcRnIf gbl lcl ()
+ifXOptM flag thing_inside = do { b <- xoptM flag;
if b then thing_inside else return () }
getGhcMode :: TcRnIf gbl lcl GhcMode
getEps :: TcRnIf gbl lcl ExternalPackageState
getEps = do { env <- getTopEnv; readMutVar (hsc_EPS env) }
--- Updating the EPS. This should be an atomic operation.
--- Note the delicate 'seq' which forces the EPS before putting it in the
--- variable. Otherwise what happens is that we get
--- write eps_var (....(unsafeRead eps_var)....)
--- and if the .... is strict, that's obviously bottom. By forcing it beforehand
--- we make the unsafeRead happen before we update the variable.
-
+-- | Update the external package state. Returns the second result of the
+-- modifier function.
+--
+-- This is an atomic operation and forces evaluation of the modified EPS in
+-- order to avoid space leaks.
updateEps :: (ExternalPackageState -> (ExternalPackageState, a))
-> TcRnIf gbl lcl a
-updateEps upd_fn = do { traceIf (text "updating EPS")
- ; eps_var <- getEpsVar
- ; eps <- readMutVar eps_var
- ; let { (eps', val) = upd_fn eps }
- ; seq eps' (writeMutVar eps_var eps')
- ; return val }
+updateEps upd_fn = do
+ traceIf (text "updating EPS")
+ eps_var <- getEpsVar
+ atomicUpdMutVar' eps_var upd_fn
+-- | Update the external package state.
+--
+-- This is an atomic operation and forces evaluation of the modified EPS in
+-- order to avoid space leaks.
updateEps_ :: (ExternalPackageState -> ExternalPackageState)
-> TcRnIf gbl lcl ()
-updateEps_ upd_fn = do { traceIf (text "updating EPS_")
- ; eps_var <- getEpsVar
- ; eps <- readMutVar eps_var
- ; let { eps' = upd_fn eps }
- ; seq eps' (writeMutVar eps_var eps') }
+updateEps_ upd_fn = do
+ traceIf (text "updating EPS_")
+ eps_var <- getEpsVar
+ atomicUpdMutVar' eps_var (\eps -> (upd_fn eps, ()))
getHpt :: TcRnIf gbl lcl HomePackageTable
getHpt = do { env <- getTopEnv; return (hsc_HPT env) }
%************************************************************************
\begin{code}
+newMetaUnique :: TcM Unique
+-- The uniques for TcMetaTyVars are allocated specially
+-- in guaranteed linear order, starting at zero for each module
+newMetaUnique
+ = do { env <- getLclEnv
+ ; let meta_var = tcl_meta env
+ ; uniq <- readMutVar meta_var
+ ; writeMutVar meta_var (incrUnique uniq)
+ ; return uniq }
+
newUnique :: TcRnIf gbl lcl Unique
newUnique
= do { env <- getEnv ;
- let { u_var = env_us env } ;
- us <- readMutVar u_var ;
- case splitUniqSupply us of { (us1,_) -> do {
- writeMutVar u_var us1 ;
- return $! uniqFromSupply us }}}
+ let { u_var = env_us env } ;
+ us <- readMutVar u_var ;
+ case takeUniqFromSupply us of { (uniq, us') -> do {
+ writeMutVar u_var us' ;
+ return $! uniq }}}
-- NOTE 1: we strictly split the supply, to avoid the possibility of leaving
-- a chain of unevaluated supplies behind.
-- NOTE 2: we use the uniq in the supply from the MutVar directly, and
newUniqueSupply :: TcRnIf gbl lcl UniqSupply
newUniqueSupply
= do { env <- getEnv ;
- let { u_var = env_us env } ;
- us <- readMutVar u_var ;
+ let { u_var = env_us env } ;
+ us <- readMutVar u_var ;
case splitUniqSupply us of { (us1,us2) -> do {
- writeMutVar u_var us1 ;
- return us2 }}}
+ writeMutVar u_var us1 ;
+ return us2 }}}
newLocalName :: Name -> TcRnIf gbl lcl Name
newLocalName name -- Make a clone
newSysLocalIds fs tys
= do { us <- newUniqueSupply
; return (zipWith (mkSysLocal fs) (uniqsFromSupply us) tys) }
+
+instance MonadUnique (IOEnv (Env gbl lcl)) where
+ getUniqueM = newUnique
+ getUniqueSupplyM = newUniqueSupply
\end{code}
%************************************************************************
\begin{code}
-traceTc, traceRn :: SDoc -> TcRn ()
+newTcRef :: a -> TcRnIf gbl lcl (TcRef a)
+newTcRef = newMutVar
+
+readTcRef :: TcRef a -> TcRnIf gbl lcl a
+readTcRef = readMutVar
+
+writeTcRef :: TcRef a -> a -> TcRnIf gbl lcl ()
+writeTcRef = writeMutVar
+
+updTcRef :: TcRef a -> (a -> a) -> TcRnIf gbl lcl ()
+updTcRef = updMutVar
+\end{code}
+
+%************************************************************************
+%* *
+ Debugging
+%* *
+%************************************************************************
+
+\begin{code}
+traceTc :: String -> SDoc -> TcRn ()
+traceTc = traceTcN 1
+
+traceTcN :: Int -> String -> SDoc -> TcRn ()
+traceTcN level herald doc
+ | level <= opt_TraceLevel = traceOptTcRn Opt_D_dump_tc_trace $
+ hang (text herald) 2 doc
+ | otherwise = return ()
+
+traceRn, traceSplice :: SDoc -> TcRn ()
traceRn = traceOptTcRn Opt_D_dump_rn_trace
-traceTc = traceOptTcRn Opt_D_dump_tc_trace
traceSplice = traceOptTcRn Opt_D_dump_splices
-
-traceIf :: SDoc -> TcRnIf m n ()
+traceIf, traceHiDiffs :: SDoc -> TcRnIf m n ()
traceIf = traceOptIf Opt_D_dump_if_trace
traceHiDiffs = traceOptIf Opt_D_dump_hi_diffs
traceOptIf :: DynFlag -> SDoc -> TcRnIf m n () -- No RdrEnv available, so qualify everything
-traceOptIf flag doc = ifOptM flag $
- ioToIOEnv (printForUser stderr alwaysQualify doc)
+traceOptIf flag doc = ifDOptM flag $
+ liftIO (printForUser stderr alwaysQualify doc)
traceOptTcRn :: DynFlag -> SDoc -> TcRn ()
-traceOptTcRn flag doc = ifOptM flag $ do
- { ctxt <- getErrCtxt
- ; loc <- getSrcSpanM
- ; env0 <- tcInitTidyEnv
- ; ctxt_msgs <- do_ctxt env0 ctxt
- ; let real_doc = mkLocMessage loc (vcat (doc : ctxt_to_use ctxt_msgs))
+-- Output the message, with current location if opt_PprStyle_Debug
+traceOptTcRn flag doc = ifDOptM flag $ do
+ { loc <- getSrcSpanM
+ ; let real_doc
+ | opt_PprStyle_Debug = mkLocMessage loc doc
+ | otherwise = doc -- The full location is
+ -- usually way too much
; dumpTcRn real_doc }
dumpTcRn :: SDoc -> TcRn ()
-dumpTcRn doc = do { rdr_env <- getGlobalRdrEnv ;
- dflags <- getDOpts ;
- ioToTcRn (printForUser stderr (mkPrintUnqualified dflags rdr_env) doc) }
+dumpTcRn doc = do { rdr_env <- getGlobalRdrEnv
+ ; dflags <- getDOpts
+ ; liftIO (printForUser stderr (mkPrintUnqualified dflags rdr_env) doc) }
+
+debugDumpTcRn :: SDoc -> TcRn ()
+debugDumpTcRn doc | opt_NoDebugOutput = return ()
+ | otherwise = dumpTcRn doc
dumpOptTcRn :: DynFlag -> SDoc -> TcRn ()
-dumpOptTcRn flag doc = ifOptM flag (dumpTcRn doc)
+dumpOptTcRn flag doc = ifDOptM flag (dumpTcRn doc)
\end{code}
setModule :: Module -> TcRn a -> TcRn a
setModule mod thing_inside = updGblEnv (\env -> env { tcg_mod = mod }) thing_inside
+getIsGHCi :: TcRn Bool
+getIsGHCi = do { mod <- getModule; return (mod == iNTERACTIVE) }
+
tcIsHsBoot :: TcRn Bool
tcIsHsBoot = do { env <- getGblEnv; return (isHsBoot (tcg_src env)) }
getGlobalRdrEnv :: TcRn GlobalRdrEnv
getGlobalRdrEnv = do { env <- getGblEnv; return (tcg_rdr_env env) }
+getRdrEnvs :: TcRn (GlobalRdrEnv, LocalRdrEnv)
+getRdrEnvs = do { (gbl,lcl) <- getEnvs; return (tcg_rdr_env gbl, tcl_rdr lcl) }
+
getImports :: TcRn ImportAvails
getImports = do { env <- getGblEnv; return (tcg_imports env) }
getRecFieldEnv :: TcRn RecFieldEnv
getRecFieldEnv = do { env <- getGblEnv; return (tcg_field_env env) }
-extendRecFieldEnv :: RecFieldEnv -> RnM a -> RnM a
-extendRecFieldEnv new_bit
- = updGblEnv (\env@(TcGblEnv { tcg_field_env = old_env }) ->
- env {tcg_field_env = old_env `plusNameEnv` new_bit})
-
getDeclaredDefaultTys :: TcRn (Maybe [Type])
getDeclaredDefaultTys = do { env <- getGblEnv; return (tcg_default env) }
\end{code}
getSrcSpanM = do { env <- getLclEnv; return (tcl_loc env) }
setSrcSpan :: SrcSpan -> TcRn a -> TcRn a
-setSrcSpan loc thing_inside
- | isGoodSrcSpan loc = updLclEnv (\env -> env { tcl_loc = loc }) thing_inside
- | otherwise = thing_inside -- Don't overwrite useful info with useless
+setSrcSpan loc@(RealSrcSpan _) thing_inside
+ = updLclEnv (\env -> env { tcl_loc = loc }) thing_inside
+-- Don't overwrite useful info with useless:
+setSrcSpan (UnhelpfulSpan _) thing_inside = thing_inside
addLocM :: (a -> TcM b) -> Located a -> TcM b
addLocM fn (L loc a) = setSrcSpan loc $ fn a
return (b, L loc c)
\end{code}
+Reporting errors
\begin{code}
getErrsVar :: TcRn (TcRef Messages)
setErrsVar :: TcRef Messages -> TcRn a -> TcRn a
setErrsVar v = updLclEnv (\ env -> env { tcl_errs = v })
-addErr :: Message -> TcRn ()
+addErr :: Message -> TcRn () -- Ignores the context stack
addErr msg = do { loc <- getSrcSpanM ; addErrAt loc msg }
-addLocErr :: Located e -> (e -> Message) -> TcRn ()
-addLocErr (L loc e) fn = addErrAt loc (fn e)
+failWith :: Message -> TcRn a
+failWith msg = addErr msg >> failM
addErrAt :: SrcSpan -> Message -> TcRn ()
-addErrAt loc msg = addLongErrAt loc msg empty
-
-addLongErrAt :: SrcSpan -> Message -> Message -> TcRn ()
-addLongErrAt loc msg extra
- = do { traceTc (ptext SLIT("Adding error:") <+> (mkLocMessage loc (msg $$ extra))) ;
- errs_var <- getErrsVar ;
- rdr_env <- getGlobalRdrEnv ;
- dflags <- getDOpts ;
- let { err = mkLongErrMsg loc (mkPrintUnqualified dflags rdr_env) msg extra } ;
- (warns, errs) <- readMutVar errs_var ;
- writeMutVar errs_var (warns, errs `snocBag` err) }
+-- addErrAt is mainly (exclusively?) used by the renamer, where
+-- tidying is not an issue, but it's all lazy so the extra
+-- work doesn't matter
+addErrAt loc msg = do { ctxt <- getErrCtxt
+ ; tidy_env <- tcInitTidyEnv
+ ; err_info <- mkErrInfo tidy_env ctxt
+ ; addLongErrAt loc msg err_info }
addErrs :: [(SrcSpan,Message)] -> TcRn ()
-addErrs msgs = mappM_ add msgs
+addErrs msgs = mapM_ add msgs
where
add (loc,msg) = addErrAt loc msg
-addReport :: Message -> TcRn ()
-addReport msg = do loc <- getSrcSpanM; addReportAt loc msg
-
-addReportAt :: SrcSpan -> Message -> TcRn ()
-addReportAt loc msg
- = do { errs_var <- getErrsVar ;
- rdr_env <- getGlobalRdrEnv ;
- dflags <- getDOpts ;
- let { warn = mkWarnMsg loc (mkPrintUnqualified dflags rdr_env) msg } ;
- (warns, errs) <- readMutVar errs_var ;
- writeMutVar errs_var (warns `snocBag` warn, errs) }
-
addWarn :: Message -> TcRn ()
-addWarn msg = addReport (ptext SLIT("Warning:") <+> msg)
+addWarn msg = addReport (ptext (sLit "Warning:") <+> msg) empty
addWarnAt :: SrcSpan -> Message -> TcRn ()
-addWarnAt loc msg = addReportAt loc (ptext SLIT("Warning:") <+> msg)
-
-addLocWarn :: Located e -> (e -> Message) -> TcRn ()
-addLocWarn (L loc e) fn = addReportAt loc (fn e)
+addWarnAt loc msg = addReportAt loc (ptext (sLit "Warning:") <+> msg) empty
checkErr :: Bool -> Message -> TcRn ()
-- Add the error if the bool is False
-checkErr ok msg = checkM ok (addErr msg)
+checkErr ok msg = unless ok (addErr msg)
warnIf :: Bool -> Message -> TcRn ()
warnIf True msg = addWarn msg
-warnIf False msg = return ()
+warnIf False _ = return ()
addMessages :: Messages -> TcRn ()
addMessages (m_warns, m_errs)
= do { errs_var <- getErrsVar ;
- (warns, errs) <- readMutVar errs_var ;
- writeMutVar errs_var (warns `unionBags` m_warns,
+ (warns, errs) <- readTcRef errs_var ;
+ writeTcRef errs_var (warns `unionBags` m_warns,
errs `unionBags` m_errs) }
discardWarnings :: TcRn a -> TcRn a
discardWarnings thing_inside
| opt_PprStyle_Debug = thing_inside
| otherwise
- = do { errs_var <- newMutVar emptyMessages
+ = do { errs_var <- newTcRef emptyMessages
; result <- setErrsVar errs_var thing_inside
- ; (_warns, errs) <- readMutVar errs_var
+ ; (_warns, errs) <- readTcRef errs_var
; addMessages (emptyBag, errs)
; return result }
\end{code}
+%************************************************************************
+%* *
+ Shared error message stuff: renamer and typechecker
+%* *
+%************************************************************************
+
+\begin{code}
+addReport :: Message -> Message -> TcRn ()
+addReport msg extra_info = do loc <- getSrcSpanM; addReportAt loc msg extra_info
+
+addReportAt :: SrcSpan -> Message -> Message -> TcRn ()
+addReportAt loc msg extra_info
+ = do { errs_var <- getErrsVar ;
+ rdr_env <- getGlobalRdrEnv ;
+ dflags <- getDOpts ;
+ let { warn = mkLongWarnMsg loc (mkPrintUnqualified dflags rdr_env)
+ msg extra_info } ;
+ (warns, errs) <- readTcRef errs_var ;
+ writeTcRef errs_var (warns `snocBag` warn, errs) }
+
+addLongErrAt :: SrcSpan -> Message -> Message -> TcRn ()
+addLongErrAt loc msg extra
+ = do { traceTc "Adding error:" (mkLocMessage loc (msg $$ extra)) ;
+ errs_var <- getErrsVar ;
+ rdr_env <- getGlobalRdrEnv ;
+ dflags <- getDOpts ;
+ let { err = mkLongErrMsg loc (mkPrintUnqualified dflags rdr_env) msg extra } ;
+ (warns, errs) <- readTcRef errs_var ;
+ writeTcRef errs_var (warns, errs `snocBag` err) }
+
+dumpDerivingInfo :: SDoc -> TcM ()
+dumpDerivingInfo doc
+ = do { dflags <- getDOpts
+ ; when (dopt Opt_D_dump_deriv dflags) $ do
+ { rdr_env <- getGlobalRdrEnv
+ ; let unqual = mkPrintUnqualified dflags rdr_env
+ ; liftIO (putMsgWith dflags unqual doc) } }
+\end{code}
+
+
\begin{code}
-try_m :: TcRn r -> TcRn (Either Exception r)
+try_m :: TcRn r -> TcRn (Either IOEnvFailure 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 "tryTc/recoverM recovering from" <+> text (showException exn)
+ Left exn -> do { traceTc "tryTc/recoverM recovering from" $
+ text (showException exn)
+ ; return mb_r }
+ Right _ -> return mb_r }
-----------------------
recoverM :: TcRn r -- Recovery action; do this if the main one fails
recoverM recover thing
= do { mb_res <- try_m thing ;
case mb_res of
- Left exn -> recover
- Right res -> returnM res }
+ Left _ -> recover
+ Right res -> return res }
+
+
+-----------------------
+mapAndRecoverM :: (a -> TcRn b) -> [a] -> TcRn [b]
+-- Drop elements of the input that fail, so the result
+-- list can be shorter than the argument list
+mapAndRecoverM _ [] = return []
+mapAndRecoverM f (x:xs) = do { mb_r <- try_m (f x)
+ ; rs <- mapAndRecoverM f xs
+ ; return (case mb_r of
+ Left _ -> rs
+ Right r -> r:rs) }
+
-----------------------
tryTc :: TcRn a -> TcRn (Messages, Maybe a)
-- It also returns all the errors and warnings accumulated by m
-- It always succeeds (never raises an exception)
tryTc m
- = do { errs_var <- newMutVar emptyMessages ;
+ = do { errs_var <- newTcRef emptyMessages ;
res <- try_m (setErrsVar errs_var m) ;
- msgs <- readMutVar errs_var ;
+ msgs <- readTcRef errs_var ;
return (msgs, case res of
- Left exn -> Nothing
+ Left _ -> Nothing
Right val -> Just val)
-- The exception is always the IOEnv built-in
-- in exception; see IOEnv.failM
-- for the thing is propagated only if there are no errors
-- Hence it's restricted to the type-check monad
tryTcLIE thing_inside
- = do { ((msgs, mb_res), lie) <- getLIE (tryTcErrs thing_inside) ;
+ = do { ((msgs, mb_res), lie) <- captureConstraints (tryTcErrs thing_inside) ;
; case mb_res of
Nothing -> return (msgs, Nothing)
- Just val -> do { extendLIEs lie; return (msgs, Just val) }
+ Just val -> do { emitConstraints lie; return (msgs, Just val) }
}
-----------------------
= do { (msgs, mb_res) <- tryTcLIE main
; addMessages msgs
; case mb_res of
- Nothing -> failM
+ Nothing -> failM
Just val -> return val
}
-- otherwise does 'main'
ifErrsM bale_out normal
= do { errs_var <- getErrsVar ;
- msgs <- readMutVar errs_var ;
+ msgs <- readTcRef errs_var ;
dflags <- getDOpts ;
if errorsFound dflags msgs then
bale_out
%************************************************************************
%* *
- Context management and error message generation
- for the type checker
+ Context management for the type checker
%* *
%************************************************************************
\begin{code}
-getErrCtxt :: TcM ErrCtxt
+getErrCtxt :: TcM [ErrCtxt]
getErrCtxt = do { env <- getLclEnv; return (tcl_ctxt env) }
-setErrCtxt :: ErrCtxt -> TcM a -> TcM a
+setErrCtxt :: [ErrCtxt] -> TcM a -> TcM a
setErrCtxt ctxt = updLclEnv (\ env -> env { tcl_ctxt = ctxt })
addErrCtxt :: Message -> TcM a -> TcM a
-addErrCtxt msg = addErrCtxtM (\env -> returnM (env, msg))
+addErrCtxt msg = addErrCtxtM (\env -> return (env, msg))
addErrCtxtM :: (TidyEnv -> TcM (TidyEnv, Message)) -> TcM a -> TcM a
-addErrCtxtM msg = updCtxt (\ msgs -> msg : msgs)
+addErrCtxtM ctxt = updCtxt (\ ctxts -> (False, ctxt) : ctxts)
+
+addLandmarkErrCtxt :: Message -> TcM a -> TcM a
+addLandmarkErrCtxt msg = updCtxt (\ctxts -> (True, \env -> return (env,msg)) : ctxts)
-- Helper function for the above
-updCtxt :: (ErrCtxt -> ErrCtxt) -> TcM a -> TcM a
+updCtxt :: ([ErrCtxt] -> [ErrCtxt]) -> TcM a -> TcM a
updCtxt upd = updLclEnv (\ env@(TcLclEnv { tcl_ctxt = ctxt }) ->
env { tcl_ctxt = upd ctxt })
--- Conditionally add an error context
-maybeAddErrCtxt :: Maybe Message -> TcM a -> TcM a
-maybeAddErrCtxt (Just msg) thing_inside = addErrCtxt msg thing_inside
-maybeAddErrCtxt Nothing thing_inside = thing_inside
-
popErrCtxt :: TcM a -> TcM a
-popErrCtxt = updCtxt (\ msgs -> case msgs of { [] -> []; (m:ms) -> ms })
+popErrCtxt = updCtxt (\ msgs -> case msgs of { [] -> []; (_ : ms) -> ms })
-getInstLoc :: InstOrigin -> TcM InstLoc
-getInstLoc origin
+getCtLoc :: orig -> TcM (CtLoc orig)
+getCtLoc origin
= do { loc <- getSrcSpanM ; env <- getLclEnv ;
- return (InstLoc origin loc (tcl_ctxt env)) }
+ return (CtLoc origin loc (tcl_ctxt env)) }
-addInstCtxt :: InstLoc -> TcM a -> TcM a
--- Add the SrcSpan and context from the first Inst in the list
--- (they all have similar locations)
-addInstCtxt (InstLoc _ src_loc ctxt) thing_inside
- = setSrcSpan src_loc (updCtxt (\ old_ctxt -> ctxt) thing_inside)
+setCtLoc :: CtLoc orig -> TcM a -> TcM a
+setCtLoc (CtLoc _ src_loc ctxt) thing_inside
+ = setSrcSpan src_loc (setErrCtxt ctxt thing_inside)
\end{code}
+%************************************************************************
+%* *
+ Error message generation (type checker)
+%* *
+%************************************************************************
+
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
; addErrTcM (env0, err_msg) }
addErrsTc :: [Message] -> TcM ()
-addErrsTc err_msgs = mappM_ addErrTc err_msgs
+addErrsTc err_msgs = mapM_ addErrTc err_msgs
addErrTcM :: (TidyEnv, Message) -> TcM ()
addErrTcM (tidy_env, err_msg)
= addErrTcM local_and_msg >> failM
checkTc :: Bool -> Message -> TcM () -- Check that the boolean is true
-checkTc True err = returnM ()
+checkTc True _ = return ()
checkTc False err = failWithTc err
\end{code}
addWarnTcM :: (TidyEnv, Message) -> TcM ()
addWarnTcM (env0, msg)
= do { ctxt <- getErrCtxt ;
- ctxt_msgs <- do_ctxt env0 ctxt ;
- addReport (vcat (ptext SLIT("Warning:") <+> msg : ctxt_to_use ctxt_msgs)) }
+ err_info <- mkErrInfo env0 ctxt ;
+ addReport (ptext (sLit "Warning:") <+> msg) err_info }
warnTc :: Bool -> Message -> TcM ()
warnTc warn_if_true warn_msg
Other helper functions
\begin{code}
+add_err_tcm :: TidyEnv -> Message -> SrcSpan
+ -> [ErrCtxt]
+ -> TcM ()
add_err_tcm tidy_env err_msg loc ctxt
- = do { ctxt_msgs <- do_ctxt tidy_env ctxt ;
- addLongErrAt loc err_msg (vcat (ctxt_to_use ctxt_msgs)) }
-
-do_ctxt tidy_env []
- = return []
-do_ctxt tidy_env (c:cs)
- = do { (tidy_env', m) <- c tidy_env ;
- ms <- do_ctxt tidy_env' cs ;
- return (m:ms) }
-
-ctxt_to_use ctxt | opt_PprStyle_Debug = ctxt
- | otherwise = take 3 ctxt
+ = do { err_info <- mkErrInfo tidy_env ctxt ;
+ addLongErrAt loc err_msg err_info }
+
+mkErrInfo :: TidyEnv -> [ErrCtxt] -> TcM SDoc
+-- Tidy the error info, trimming excessive contexts
+mkErrInfo env ctxts
+ | opt_PprStyle_Debug -- In -dppr-debug style the output
+ = return empty -- just becomes too voluminous
+ | otherwise
+ = go 0 env ctxts
+ where
+ go :: Int -> TidyEnv -> [ErrCtxt] -> TcM SDoc
+ go _ _ [] = return empty
+ go n env ((is_landmark, ctxt) : ctxts)
+ | is_landmark || n < mAX_CONTEXTS -- Too verbose || opt_PprStyle_Debug
+ = do { (env', msg) <- ctxt env
+ ; let n' = if is_landmark then n else n+1
+ ; rest <- go n' env' ctxts
+ ; return (msg $$ rest) }
+ | otherwise
+ = go n env ctxts
+
+mAX_CONTEXTS :: Int -- No more than this number of non-landmark contexts
+mAX_CONTEXTS = 3
\end{code}
debugTc is useful for monadic debugging code
\begin{code}
debugTc :: TcM () -> TcM ()
-#ifdef DEBUG
-debugTc thing = thing
-#else
-debugTc thing = return ()
-#endif
+debugTc thing
+ | debugIsOn = thing
+ | otherwise = return ()
\end{code}
- %************************************************************************
+%************************************************************************
%* *
- Type constraints (the so-called LIE)
+ Type constraints
%* *
%************************************************************************
\begin{code}
-nextDFunIndex :: TcM Int -- Get the next dfun index
-nextDFunIndex = do { env <- getGblEnv
- ; let dfun_n_var = tcg_dfun_n env
- ; n <- readMutVar dfun_n_var
- ; writeMutVar dfun_n_var (n+1)
- ; return n }
-
-getLIEVar :: TcM (TcRef LIE)
-getLIEVar = do { env <- getLclEnv; return (tcl_lie env) }
-
-setLIEVar :: TcRef LIE -> TcM a -> TcM a
-setLIEVar lie_var = updLclEnv (\ env -> env { tcl_lie = lie_var })
-
-getLIE :: TcM a -> TcM (a, [Inst])
--- (getLIE m) runs m, and returns the type constraints it generates
-getLIE thing_inside
- = do { lie_var <- newMutVar emptyLIE ;
- res <- updLclEnv (\ env -> env { tcl_lie = lie_var })
- thing_inside ;
- lie <- readMutVar lie_var ;
- return (res, lieToList lie) }
-
-extendLIE :: Inst -> TcM ()
-extendLIE inst
- = do { lie_var <- getLIEVar ;
- lie <- readMutVar lie_var ;
- writeMutVar lie_var (inst `consLIE` lie) }
-
-extendLIEs :: [Inst] -> TcM ()
-extendLIEs []
- = returnM ()
-extendLIEs insts
- = do { lie_var <- getLIEVar ;
- lie <- readMutVar lie_var ;
- writeMutVar lie_var (mkLIE insts `plusLIE` lie) }
-\end{code}
+newTcEvBinds :: TcM EvBindsVar
+newTcEvBinds = do { ref <- newTcRef emptyEvBindMap
+ ; uniq <- newUnique
+ ; return (EvBindsVar ref uniq) }
+
+extendTcEvBinds :: TcEvBinds -> EvVar -> EvTerm -> TcM TcEvBinds
+extendTcEvBinds binds@(TcEvBinds binds_var) var rhs
+ = do { addTcEvBind binds_var var rhs
+ ; return binds }
+extendTcEvBinds (EvBinds bnds) var rhs
+ = return (EvBinds (bnds `snocBag` EvBind var rhs))
+
+addTcEvBind :: EvBindsVar -> EvVar -> EvTerm -> TcM ()
+-- Add a binding to the TcEvBinds by side effect
+addTcEvBind (EvBindsVar ev_ref _) var rhs
+ = do { bnds <- readTcRef ev_ref
+ ; writeTcRef ev_ref (extendEvBinds bnds var rhs) }
+
+chooseUniqueOccTc :: (OccSet -> OccName) -> TcM OccName
+chooseUniqueOccTc fn =
+ do { env <- getGblEnv
+ ; let dfun_n_var = tcg_dfun_n env
+ ; set <- readTcRef dfun_n_var
+ ; let occ = fn set
+ ; writeTcRef dfun_n_var (extendOccSet set occ)
+ ; return occ }
+
+getConstraintVar :: TcM (TcRef WantedConstraints)
+getConstraintVar = do { env <- getLclEnv; return (tcl_lie env) }
+
+setConstraintVar :: TcRef WantedConstraints -> TcM a -> TcM a
+setConstraintVar lie_var = updLclEnv (\ env -> env { tcl_lie = lie_var })
+
+emitConstraints :: WantedConstraints -> TcM ()
+emitConstraints ct
+ = do { lie_var <- getConstraintVar ;
+ updTcRef lie_var (`andWC` ct) }
+
+emitFlat :: WantedEvVar -> TcM ()
+emitFlat ct
+ = do { lie_var <- getConstraintVar ;
+ updTcRef lie_var (`addFlats` unitBag ct) }
+
+emitFlats :: Bag WantedEvVar -> TcM ()
+emitFlats ct
+ = do { lie_var <- getConstraintVar ;
+ updTcRef lie_var (`addFlats` ct) }
+
+emitImplication :: Implication -> TcM ()
+emitImplication ct
+ = do { lie_var <- getConstraintVar ;
+ updTcRef lie_var (`addImplics` unitBag ct) }
+
+emitImplications :: Bag Implication -> TcM ()
+emitImplications ct
+ = do { lie_var <- getConstraintVar ;
+ updTcRef lie_var (`addImplics` ct) }
+
+captureConstraints :: TcM a -> TcM (a, WantedConstraints)
+-- (captureConstraints m) runs m, and returns the type constraints it generates
+captureConstraints thing_inside
+ = do { lie_var <- newTcRef emptyWC ;
+ res <- updLclEnv (\ env -> env { tcl_lie = lie_var })
+ thing_inside ;
+ lie <- readTcRef lie_var ;
+ return (res, lie) }
+
+captureUntouchables :: TcM a -> TcM (a, Untouchables)
+captureUntouchables thing_inside
+ = do { env <- getLclEnv
+ ; low_meta <- readTcRef (tcl_meta env)
+ ; res <- setLclEnv (env { tcl_untch = low_meta })
+ thing_inside
+ ; high_meta <- readTcRef (tcl_meta env)
+ ; return (res, TouchableRange low_meta high_meta) }
+
+isUntouchable :: TcTyVar -> TcM Bool
+isUntouchable tv = do { env <- getLclEnv
+ ; return (varUnique tv < tcl_untch env) }
+
+getLclTypeEnv :: TcM (NameEnv TcTyThing)
+getLclTypeEnv = do { env <- getLclEnv; return (tcl_env env) }
-\begin{code}
setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a
-- Set the local type envt, but do *not* disturb other fields,
-- notably the lie_var
= updLclEnv upd thing_inside
where
upd env = env { tcl_env = tcl_env lcl_env,
- tcl_tyvars = tcl_tyvars lcl_env }
+ tcl_tyvars = tcl_tyvars lcl_env }
+
+traceTcConstraints :: String -> TcM ()
+traceTcConstraints msg
+ = do { lie_var <- getConstraintVar
+ ; lie <- readTcRef lie_var
+ ; traceTc (msg ++ "LIE:") (ppr lie)
+ }
\end{code}
%************************************************************************
-%* *
- Template Haskell context
-%* *
+%* *
+ Template Haskell context
+%* *
%************************************************************************
\begin{code}
recordThUse :: TcM ()
-recordThUse = do { env <- getGblEnv; writeMutVar (tcg_th_used env) True }
+recordThUse = do { env <- getGblEnv; writeTcRef (tcg_th_used env) True }
keepAliveTc :: Id -> TcM () -- Record the name in the keep-alive set
keepAliveTc id
| isLocalId id = do { env <- getGblEnv;
- ; updMutVar (tcg_keep env) (`addOneToNameSet` idName id) }
+ ; updTcRef (tcg_keep env) (`addOneToNameSet` idName id) }
| otherwise = return ()
keepAliveSetTc :: NameSet -> TcM () -- Record the name in the keep-alive set
keepAliveSetTc ns = do { env <- getGblEnv;
- ; updMutVar (tcg_keep env) (`unionNameSets` ns) }
+ ; updTcRef (tcg_keep env) (`unionNameSets` ns) }
getStage :: TcM ThStage
getStage = do { env <- getLclEnv; return (tcl_th_ctxt env) }
initIfaceTcRn thing_inside
= do { tcg_env <- getGblEnv
; let { if_env = IfGblEnv { if_rec_types = Just (tcg_mod tcg_env, get_type_env) }
- ; get_type_env = readMutVar (tcg_type_env_var tcg_env) }
+ ; get_type_env = readTcRef (tcg_type_env_var tcg_env) }
; setEnvs (if_env, ()) thing_inside }
initIfaceExtCore :: IfL a -> TcRn a
initIfaceExtCore thing_inside
= do { tcg_env <- getGblEnv
; let { mod = tcg_mod tcg_env
- ; doc = ptext SLIT("External Core file for") <+> quotes (ppr mod)
+ ; doc = ptext (sLit "External Core file for") <+> quotes (ppr mod)
; if_env = IfGblEnv {
if_rec_types = Just (mod, return (tcg_type_env tcg_env)) }
; if_lenv = mkIfLclEnv mod doc
-- Used when checking the up-to-date-ness of the old Iface
-- Initialise the environment with no useful info at all
initIfaceCheck hsc_env do_this
- = do { let gbl_env = IfGblEnv { if_rec_types = Nothing }
- ; initTcRnIf 'i' hsc_env gbl_env () do_this
- }
+ = do let rec_types = case hsc_type_env_var hsc_env of
+ Just (mod,var) -> Just (mod, readTcRef var)
+ Nothing -> Nothing
+ gbl_env = IfGblEnv { if_rec_types = rec_types }
+ initTcRnIf 'i' hsc_env gbl_env () do_this
initIfaceTc :: ModIface
-> (TcRef TypeEnv -> IfL a) -> TcRnIf gbl lcl a
-- Used when type-checking checking an up-to-date interface file
-- No type envt from the current module, but we do know the module dependencies
initIfaceTc iface do_this
- = do { tc_env_var <- newMutVar emptyTypeEnv
- ; let { gbl_env = IfGblEnv { if_rec_types = Just (mod, readMutVar tc_env_var) } ;
+ = do { tc_env_var <- newTcRef emptyTypeEnv
+ ; let { gbl_env = IfGblEnv { if_rec_types = Just (mod, readTcRef tc_env_var) } ;
; if_lenv = mkIfLclEnv mod doc
}
; setEnvs (gbl_env, if_lenv) (do_this tc_env_var)
}
where
mod = mi_module iface
- doc = ptext SLIT("The interface for") <+> quotes (ppr mod)
+ doc = ptext (sLit "The interface for") <+> quotes (ppr mod)
initIfaceRules :: HscEnv -> ModGuts -> IfG a -> IO a
-- Used when sucking in new Rules in SimplCore
failIfM msg
= do { env <- getLclEnv
; let full_msg = (if_loc env <> colon) $$ nest 2 msg
- ; ioToIOEnv (printErrs (full_msg defaultErrStyle))
+ ; liftIO (printErrs full_msg defaultErrStyle)
; failM }
--------------------
-- Bleat about errors in the forked thread, if -ddump-if-trace is on
-- Otherwise we silently discard errors. Errors can legitimately
-- happen when compiling interface signatures (see tcInterfaceSigs)
- ifOptM Opt_D_dump_if_trace
+ ifDOptM Opt_D_dump_if_trace
(print_errs (hang (text "forkM failed:" <+> doc)
- 4 (text (show exn))))
+ 2 (text (show exn))))
; traceIf (text "} ending fork (badly)" <+> doc)
; return Nothing }
}}
where
- print_errs sdoc = ioToIOEnv (printErrs (sdoc defaultErrStyle))
+ print_errs sdoc = liftIO (printErrs sdoc defaultErrStyle)
forkM :: SDoc -> IfL a -> IfL a
forkM doc thing_inside
projects / ghc-hetmet.git / blobdiff