-- Non-standard operations
runTcRn, fixM, tryM, ioToTcRn,
newMutVar, readMutVar, writeMutVar,
- getEnv, setEnv, updEnv, unsafeInterleaveM,
+ getEnv, setEnv, updEnv, unsafeInterleaveM, zapEnv,
-- The environment types
Env(..), TopEnv(..), TcGblEnv(..),
ImportAvails(..), emptyImportAvails, plusImportAvails,
plusAvail, pruneAvails,
AvailEnv, emptyAvailEnv, unitAvailEnv, plusAvailEnv,
- mkAvailEnv, lookupAvailEnv, availEnvElts, addAvail,
+ mkAvailEnv, lookupAvailEnv, lookupAvailEnv_maybe, availEnvElts, addAvail,
WhereFrom(..),
-- Typechecker types
import HsSyn ( PendingSplice, HsOverLit, MonoBinds, RuleDecl, ForeignDecl )
import RnHsSyn ( RenamedHsExpr, RenamedPat, RenamedArithSeqInfo )
-import HscTypes ( GhciMode, ExternalPackageState, HomePackageTable, NameCache,
- GlobalRdrEnv, LocalRdrEnv, FixityEnv, TypeEnv, TyThing,
- Avails, GenAvailInfo(..), AvailInfo, availName,
- IsBootInterface, Deprecations )
+import HscTypes ( GhciMode, ExternalPackageState, HomePackageTable,
+ NameCache, GlobalRdrEnv, LocalRdrEnv, FixityEnv,
+ TypeEnv, TyThing, Avails, GenAvailInfo(..), AvailInfo,
+ availName, IsBootInterface, Deprecations,
+ ExternalPackageState(..), emptyExternalPackageState )
import Packages ( PackageName )
-import TcType ( TcTyVarSet, TcType, TcTauType, TcThetaType, TcPredType, TcKind,
- tcCmpPred, tcCmpType, tcCmpTypes )
+import TcType ( TcTyVarSet, TcType, TcTauType, TcThetaType,
+ TcPredType, TcKind, tcCmpPred, tcCmpType, tcCmpTypes )
import InstEnv ( DFunId, InstEnv )
import Name ( Name )
import NameEnv
import DATA_IOREF ( IORef, newIORef, readIORef, writeIORef )
import UNSAFE_IO ( unsafeInterleaveIO )
import FIX_IO ( fixIO )
-import EXCEPTION ( Exception )
+import EXCEPTION ( Exception(..) )
+import IO ( isUserError )
import Maybe ( mapMaybe )
import ListSetOps ( unionLists )
-import Panic ( tryMost )
+import Panic ( tryJust )
\end{code}
\begin{code}
tryM :: TcRn m r -> TcRn m (Either Exception r)
-- Reflect exception into TcRn monad
-tryM (TcRn thing) = TcRn (\ env -> tryMost (thing env))
+tryM (TcRn thing) = TcRn (\ env -> tryJust tc_errors (thing env))
+ where
+#if __GLASGOW_HASKELL__ > 504 || __GLASGOW_HASKELL__ < 500
+ tc_errors e@(IOException ioe) | isUserError ioe = Just e
+#else
+ tc_errors e@(IOException _) | isUserError e = Just e
+#endif
+ tc_errors _other = Nothing
+ -- type checker failures show up as UserErrors only
\end{code}
Lazy interleave
updEnv upd (TcRn m) = TcRn (\ env -> m (upd env))
\end{code}
+\begin{code}
+zapEnv :: TcRn m a -> TcRn m a
+zapEnv act = TcRn $ \env@Env{ env_top=top, env_gbl=gbl, env_lcl=lcl } ->
+ case top of {
+ TopEnv{
+ top_mode = mode,
+ top_dflags = dflags,
+ top_hpt = hpt,
+ top_eps = eps,
+ top_us = us
+ } -> do
+
+ eps_snap <- readIORef eps
+ ref <- newIORef $! emptyExternalPackageState{ eps_PTE = eps_PTE eps_snap }
+
+ let
+ top' = TopEnv {
+ top_mode = mode,
+ top_dflags = dflags,
+ top_hpt = hpt,
+ top_eps = ref,
+ top_us = us
+ }
+
+ type_env = tcg_type_env gbl
+ mod = tcg_mod gbl
+ gbl' = TcGblEnv {
+ tcg_mod = mod,
+ tcg_type_env = type_env
+ }
+
+ env' = Env {
+ env_top = top',
+ env_gbl = gbl',
+ env_lcl = lcl
+ -- leave the rest empty
+ }
+
+ case act of { TcRn f -> f env' }
+ }
+\end{code}
%************************************************************************
%* *
-- PIT, ImportedModuleInfo
-- DeclsMap, IfaceRules, IfaceInsts, InstGates
-- TypeEnv, InstEnv, RuleBase
+ -- Mutable, because we demand-load declarations that extend the state
top_hpt :: HomePackageTable,
-- The home package table that we've accumulated while
-- (Ids defined in this module start in the local envt,
-- though they move to the global envt during zonking)
- -- Cached things
- tcg_ist :: Name -> Maybe TyThing, -- Imported symbol table
- -- Global type env: a combination of tcg_eps, tcg_hpt
- -- (but *not* tcg_type_env; no deep reason)
- -- When the PCS changes this must be refreshed,
- -- notably after running some compile-time code
-
- tcg_inst_env :: InstEnv, -- Global instance env: a combination of
+ tcg_inst_env :: TcRef InstEnv, -- Global instance env: a combination of
-- tc_pcs, tc_hpt, *and* tc_insts
+ -- This field is mutable so that it can be updated inside a
+ -- Template Haskell splice, which might suck in some new
+ -- instance declarations. This is a slightly different strategy
+ -- than for the type envt, where we look up first in tcg_type_env
+ -- and then in the mutable EPS, because the InstEnv for this module
+ -- is constructed (in principle at least) only from the modules
+ -- 'below' this one, so it's this-module-specific
+ --
+ -- On the other hand, a declaration quote [d| ... |] may introduce
+ -- some new instance declarations that we *don't* want to persist
+ -- outside the quote, so we tiresomely need to revert the InstEnv
+ -- after finishing the quote (see TcSplice.tcBracket)
-- Now a bunch of things about this module that are simply
-- accumulated, but never consulted until the end.
tcg_imports :: ImportAvails, -- Information about what was imported
-- from where, including things bound
-- in this module
- -- The next fields are always fully zonked
+
+ -- The next fields accumulate the payload of the module
+ -- The binds, rules and foreign-decl fiels are collected
+ -- initially in un-zonked form and are finally zonked in tcRnSrcDecls
tcg_binds :: MonoBinds Id, -- Value bindings in this module
tcg_deprecs :: Deprecations, -- ...Deprecations
tcg_insts :: [DFunId], -- ...Instances
impLevel, topLevel :: Level
-topLevel = 1 -- Things dedined at top level of this module
+topLevel = 1 -- Things defined at top level of this module
impLevel = 0 -- Imported things; they can be used inside a top level splice
--
-- For example:
ImportAvails summarises what was imported from where, irrespective
of whether the imported htings are actually used or not
-It is used * when porcessing the export list
+It is used * when processing the export list
* when constructing usage info for the inteface file
* to identify the list of directly imported modules
for initialisation purposes
+ * when figuring out what things are really unused
\begin{code}
data ImportAvails
plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
plusAvailEnv = plusNameEnv_C plusAvail
-lookupAvailEnv = lookupNameEnv
+lookupAvailEnv_maybe :: AvailEnv -> Name -> Maybe AvailInfo
+lookupAvailEnv_maybe = lookupNameEnv
+
+lookupAvailEnv :: AvailEnv -> Name -> AvailInfo
+lookupAvailEnv env n = case lookupNameEnv env n of
+ Just avail -> avail
+ Nothing -> pprPanic "lookupAvailEnv" (ppr n)
availEnvElts = nameEnvElts
TcThetaType -- The (types of the) dictionaries to which the function
-- must be applied to get the method
- TcTauType -- The type of the method
+ TcTauType -- The tau-type of the method
InstLoc
- -- INVARIANT: in (Method u f tys theta tau loc)
+ -- INVARIANT 1: in (Method u f tys theta tau loc)
-- type of (f tys dicts(from theta)) = tau
+ -- INVARIANT 2: tau must not be of form (Pred -> Tau)
+ -- Reason: two methods are considerd equal if the
+ -- base Id matches, and the instantiating types
+ -- match. The TcThetaType should then match too.
+ -- This only bites in the call to tcInstClassOp in TcClassDcl.mkMethodBind
+
| LitInst
Id
HsOverLit -- The literal from the occurrence site
projects / ghc-hetmet.git / blobdiff