\begin{code}
module RnIfaces
- (
- findAndReadIface,
-
+ (
getInterfaceExports,
- getImportedInstDecls, getImportedRules,
- lookupFixityRn, loadHomeInterface,
- importDecl, ImportDeclResult(..), recordLocalSlurps, loadBuiltinRules,
- mkImportExportInfo, getSlurped,
+ recordLocalSlurps,
+ mkImportInfo,
+
+ slurpImpDecls, closeDecls,
- getDeclBinders, getDeclSysBinders,
- removeContext -- removeContext probably belongs somewhere else
+ RecompileRequired, outOfDate, upToDate, recompileRequired
)
where
#include "HsVersions.h"
-import CmdLineOpts ( opt_NoPruneDecls, opt_NoPruneTyDecls, opt_IgnoreIfacePragmas )
-import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..),
- HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..),
- ForeignDecl(..), ForKind(..), isDynamicExtName,
- FixitySig(..), RuleDecl(..),
- isClassOpSig, DeprecDecl(..)
+import CmdLineOpts ( DynFlags, opt_NoPruneDecls, opt_NoPruneTyDecls, opt_IgnoreIfacePragmas )
+import HscTypes
+import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..),
+ InstDecl(..), HsType(..), hsTyVarNames, getBangType
)
-import HsImpExp ( ieNames )
-import CoreSyn ( CoreRule )
-import BasicTypes ( Version, defaultFixity )
-import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameRuleDecl,
- RdrNameDeprecation, RdrNameIE,
- extractHsTyRdrNames
+import HsImpExp ( ImportDecl(..) )
+import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl, RdrNameInstDecl )
+import RnHsSyn ( RenamedHsDecl, extractHsTyNames, extractHsCtxtTyNames, tyClDeclFVs )
+import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface,
+ loadOrphanModules
)
+import RnSource ( rnTyClDecl, rnDecl )
import RnEnv
import RnMonad
-import ParseIface ( parseIface, IfaceStuff(..) )
-
+import Id ( idType )
+import Type ( namesOfType )
+import TyCon ( isSynTyCon, getSynTyConDefn )
import Name ( Name {-instance NamedThing-}, nameOccName,
- nameModule, isLocallyDefined,
+ nameModule, isLocallyDefined, nameUnique,
NamedThing(..),
- mkNameEnv, elemNameEnv, extendNameEnv
+ elemNameEnv
)
-import Module ( Module,
+import Module ( Module, ModuleEnv,
moduleName, isModuleInThisPackage,
ModuleName, WhereFrom(..),
- extendModuleEnv, lookupModuleEnv, lookupModuleEnvByName
+ emptyModuleEnv, lookupModuleEnvByName,
+ extendModuleEnv_C, lookupWithDefaultModuleEnv
)
-import RdrName ( RdrName, rdrNameOcc )
import NameSet
-import SrcLoc ( mkSrcLoc, SrcLoc )
-import PrelInfo ( cCallishTyKeys, wiredInThingEnv )
-import Maybes ( maybeToBool, orElse )
-import StringBuffer ( hGetStringBuffer )
-import FastString ( mkFastString )
-import ErrUtils ( Message )
-import Util ( sortLt )
-import Lex
+import PrelInfo ( wiredInThingEnv, fractionalClassKeys )
+import TysWiredIn ( doubleTyCon )
+import Maybes ( orElse )
import FiniteMap
import Outputable
import Bag
-import HscTypes
-
-import List ( nub )
-\end{code}
-
-
-%*********************************************************
-%* *
-\subsection{Loading a new interface file}
-%* *
-%*********************************************************
-
-\begin{code}
-loadHomeInterface :: SDoc -> Name -> RnM d Ifaces
-loadHomeInterface doc_str name
- = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem
-
-loadOrphanModules :: [ModuleName] -> RnM d ()
-loadOrphanModules mods
- | null mods = returnRn ()
- | otherwise = traceRn (text "Loading orphan modules:" <+>
- fsep (map ppr mods)) `thenRn_`
- mapRn_ load mods `thenRn_`
- returnRn ()
- where
- load mod = loadInterface (mk_doc mod) mod ImportBySystem
- mk_doc mod = ppr mod <+> ptext SLIT("is a orphan-instance module")
-
-
-loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d Ifaces
-loadInterface doc mod from
- = tryLoadInterface doc mod from `thenRn` \ (ifaces, maybe_err) ->
- case maybe_err of
- Nothing -> returnRn ifaces
- Just err -> failWithRn ifaces err
-
-tryLoadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Ifaces, Maybe Message)
- -- Returns (Just err) if an error happened
- -- Guarantees to return with iImpModInfo m --> (... Just cts)
- -- (If the load fails, we plug in a vanilla placeholder
-tryLoadInterface doc_str mod_name from
- = getIfacesRn `thenRn` \ ifaces ->
- let
- mod_map = iImpModInfo ifaces
- mod_info = lookupFM mod_map mod_name
-
- hi_boot_file
- = case (from, mod_info) of
- (ImportByUser, _) -> False -- Not hi-boot
- (ImportByUserSource, _) -> True -- hi-boot
- (ImportBySystem, Just (_, is_boot, _)) -> is_boot --
- (ImportBySystem, Nothing) -> False
- -- We're importing a module we know absolutely
- -- nothing about, so we assume it's from
- -- another package, where we aren't doing
- -- dependency tracking. So it won't be a hi-boot file.
-
- redundant_source_import
- = case (from, mod_info) of
- (ImportByUserSource, Just (_,False,_)) -> True
- other -> False
- in
- -- CHECK WHETHER WE HAVE IT ALREADY
- case mod_info of {
- Just (_, _, True)
- -> -- We're read it already so don't re-read it
- returnRn (ifaces, Nothing) ;
-
- _ ->
-
- -- Issue a warning for a redundant {- SOURCE -} import
- -- NB that we arrange to read all the ordinary imports before
- -- any of the {- SOURCE -} imports
- warnCheckRn (not redundant_source_import)
- (warnRedundantSourceImport mod_name) `thenRn_`
-
- -- READ THE MODULE IN
- findAndReadIface doc_str mod_name hi_boot_file `thenRn` \ read_result ->
- case read_result of {
- Left err -> -- Not found, so add an empty export env to the Ifaces map
- -- so that we don't look again
- let
- new_mod_map = addToFM mod_map mod_name (False, False, True)
- new_ifaces = ifaces { iImpModInfo = new_mod_map }
- in
- setIfacesRn new_ifaces `thenRn_`
- returnRn (new_ifaces, Just err) ;
-
- -- Found and parsed!
- Right (mod, iface) ->
-
- -- LOAD IT INTO Ifaces
-
- -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
- --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
- -- If we do loadExport first the wrong info gets into the cache (unless we
- -- explicitly tag each export which seems a bit of a bore)
-
-
- -- Sanity check. If we're system-importing a module we know nothing at all
- -- about, it should be from a different package to this one
- WARN( not (maybeToBool mod_info) &&
- case from of { ImportBySystem -> True; other -> False } &&
- isModuleInThisPackage mod,
- ppr mod )
-
- loadDecls mod (iDecls ifaces) (pi_decls iface) `thenRn` \ (decls_vers, new_decls) ->
- loadRules mod (iRules ifaces) (pi_rules iface) `thenRn` \ (rule_vers, new_rules) ->
- loadFixDecls mod_name (pi_fixity iface) `thenRn` \ (fix_vers, fix_env) ->
- foldlRn (loadDeprec mod) emptyNameEnv (pi_deprecs iface) `thenRn` \ deprec_env ->
- foldlRn (loadInstDecl mod) (iInsts ifaces) (pi_insts iface) `thenRn` \ new_insts ->
- loadExports (pi_exports iface) `thenRn` \ avails ->
- let
- version = VersionInfo { modVers = pi_vers iface,
- fixVers = fix_vers,
- ruleVers = rule_vers,
- declVers = decls_vers }
-
- -- For an explicit user import, add to mod_map info about
- -- the things the imported module depends on, extracted
- -- from its usage info.
- mod_map1 = case from of
- ImportByUser -> addModDeps mod (pi_usages iface) mod_map
- other -> mod_map
- mod_map2 = addToFM mod_map1 mod_name (has_orphans, hi_boot_file, True)
-
- -- Now add info about this module to the PIT
- has_orphans = pi_orphan iface
- new_pit = extendModuleEnv (iPIT ifaces) mod mod_iface
- mod_iface = ModIface { mi_module = mod, mi_version = version,
- mi_exports = avails, mi_orphan = has_orphans,
- mi_fixities = fix_env, mi_deprecs = deprec_env,
- mi_usages = [], -- Will be filled in later
- mi_decls = panic "No mi_decls in PIT",
- mi_globals = panic "No mi_globals in PIT"
- }
-
- new_ifaces = ifaces { iPIT = new_pit,
- iDecls = new_decls,
- iInsts = new_insts,
- iRules = new_rules,
- iImpModInfo = mod_map2 }
- in
- setIfacesRn new_ifaces `thenRn_`
- returnRn (new_ifaces, Nothing)
- }}
-
------------------------------------------------------
--- Adding module dependencies from the
--- import decls in the interface file
------------------------------------------------------
-
-addModDeps :: Module -> [ImportVersion a]
- -> ImportedModuleInfo -> ImportedModuleInfo
--- (addModDeps M ivs deps)
--- We are importing module M, and M.hi contains 'import' decls given by ivs
-addModDeps mod new_deps mod_deps
- = foldr add mod_deps filtered_new_deps
- where
- -- Don't record dependencies when importing a module from another package
- -- Except for its descendents which contain orphans,
- -- and in that case, forget about the boot indicator
- filtered_new_deps :: [(ModuleName, (WhetherHasOrphans, IsBootInterface))]
- filtered_new_deps
- | isModuleInThisPackage mod
- = [ (imp_mod, (has_orphans, is_boot, False))
- | (imp_mod, has_orphans, is_boot, _) <- new_deps
- ]
- | otherwise = [ (imp_mod, (True, False, False))
- | (imp_mod, has_orphans, _, _) <- new_deps,
- has_orphans
- ]
- add (imp_mod, dep) deps = addToFM_C combine deps imp_mod dep
-
- combine old@(_, old_is_boot, old_is_loaded) new
- | old_is_loaded || not old_is_boot = old -- Keep the old info if it's already loaded
- -- or if it's a non-boot pending load
- | otherwise = new -- Otherwise pick new info
-
-
------------------------------------------------------
--- Loading the export list
------------------------------------------------------
-
-loadExports :: [ExportItem] -> RnM d Avails
-loadExports items
- = getModuleRn `thenRn` \ this_mod ->
- mapRn (loadExport this_mod) items `thenRn` \ avails_s ->
- returnRn (concat avails_s)
-
-
-loadExport :: Module -> ExportItem -> RnM d [AvailInfo]
-loadExport this_mod (mod, entities)
- | mod == moduleName this_mod = returnRn []
- -- If the module exports anything defined in this module, just ignore it.
- -- Reason: otherwise it looks as if there are two local definition sites
- -- for the thing, and an error gets reported. Easiest thing is just to
- -- filter them out up front. This situation only arises if a module
- -- imports itself, or another module that imported it. (Necessarily,
- -- this invoves a loop.) Consequence: if you say
- -- module A where
- -- import B( AType )
- -- type AType = ...
- --
- -- module B( AType ) where
- -- import {-# SOURCE #-} A( AType )
- --
- -- then you'll get a 'B does not export AType' message. A bit bogus
- -- but it's a bogus thing to do!
- | otherwise
- = mapRn (load_entity mod) entities
- where
- new_name mod occ = newGlobalName mod occ
-
- load_entity mod (Avail occ)
- = new_name mod occ `thenRn` \ name ->
- returnRn (Avail name)
- load_entity mod (AvailTC occ occs)
- = new_name mod occ `thenRn` \ name ->
- mapRn (new_name mod) occs `thenRn` \ names ->
- returnRn (AvailTC name names)
-
-
------------------------------------------------------
--- Loading type/class/value decls
------------------------------------------------------
-
-loadDecls :: Module
- -> DeclsMap
- -> [(Version, RdrNameHsDecl)]
- -> RnM d (NameEnv Version, DeclsMap)
-loadDecls mod decls_map decls
- = foldlRn (loadDecl mod) (emptyNameEnv, decls_map) decls
-
-loadDecl :: Module
- -> (NameEnv Version, DeclsMap)
- -> (Version, RdrNameHsDecl)
- -> RnM d (NameEnv Version, DeclsMap)
-loadDecl mod (version_map, decls_map) (version, decl)
- = getDeclBinders new_name decl `thenRn` \ maybe_avail ->
- case maybe_avail of {
- Nothing -> returnRn (version_map, decls_map); -- No bindings
- Just avail ->
-
- getDeclSysBinders new_name decl `thenRn` \ sys_bndrs ->
- let
- full_avail = addSysAvails avail sys_bndrs
- -- Add the sys-binders to avail. When we import the decl,
- -- it's full_avail that will get added to the 'already-slurped' set (iSlurp)
- -- If we miss out sys-binders, we'll read the decl multiple times!
-
- main_name = availName avail
- new_decls_map = foldl add_decl decls_map
- [ (name, (full_avail, name==main_name, (mod, decl')))
- | name <- availNames full_avail]
- add_decl decls_map (name, stuff)
- = WARN( name `elemNameEnv` decls_map, ppr name )
- extendNameEnv decls_map name stuff
-
- new_version_map = extendNameEnv version_map main_name version
- in
- returnRn (new_version_map, new_decls_map)
- }
- where
- -- newTopBinder puts into the cache the binder with the
- -- module information set correctly. When the decl is later renamed,
- -- the binding site will thereby get the correct module.
- -- There maybe occurrences that don't have the correct Module, but
- -- by the typechecker will propagate the binding definition to all
- -- the occurrences, so that doesn't matter
- new_name rdr_name loc = newTopBinder mod rdr_name loc
-
- {-
- If a signature decl is being loaded, and optIgnoreIfacePragmas is on,
- we toss away unfolding information.
-
- Also, if the signature is loaded from a module we're importing from source,
- we do the same. This is to avoid situations when compiling a pair of mutually
- recursive modules, peering at unfolding info in the interface file of the other,
- e.g., you compile A, it looks at B's interface file and may as a result change
- its interface file. Hence, B is recompiled, maybe changing its interface file,
- which will the unfolding info used in A to become invalid. Simple way out is to
- just ignore unfolding info.
-
- [Jan 99: I junked the second test above. If we're importing from an hi-boot
- file there isn't going to *be* any pragma info. Maybe the above comment
- dates from a time where we picked up a .hi file first if it existed?]
- -}
- decl' = case decl of
- SigD (IfaceSig name tp ls loc) | opt_IgnoreIfacePragmas
- -> SigD (IfaceSig name tp [] loc)
- other -> decl
-
------------------------------------------------------
--- Loading fixity decls
------------------------------------------------------
-
-loadFixDecls mod_name (version, decls)
- = mapRn (loadFixDecl mod_name) decls `thenRn` \ to_add ->
- returnRn (version, mkNameEnv to_add)
-
-loadFixDecl mod_name sig@(FixitySig rdr_name fixity loc)
- = newGlobalName mod_name (rdrNameOcc rdr_name) `thenRn` \ name ->
- returnRn (name, fixity)
-
-
------------------------------------------------------
--- Loading instance decls
------------------------------------------------------
-
-loadInstDecl :: Module
- -> IfaceInsts
- -> RdrNameInstDecl
- -> RnM d IfaceInsts
-loadInstDecl mod insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
- =
- -- Find out what type constructors and classes are "gates" for the
- -- instance declaration. If all these "gates" are slurped in then
- -- we should slurp the instance decl too.
- --
- -- We *don't* want to count names in the context part as gates, though.
- -- For example:
- -- instance Foo a => Baz (T a) where ...
- --
- -- Here the gates are Baz and T, but *not* Foo.
- let
- munged_inst_ty = removeContext inst_ty
- free_names = extractHsTyRdrNames munged_inst_ty
- in
- setModuleRn mod $
- mapRn lookupOrigName free_names `thenRn` \ gate_names ->
- returnRn ((mkNameSet gate_names, (mod, InstD decl)) `consBag` insts)
-
-
--- In interface files, the instance decls now look like
--- forall a. Foo a -> Baz (T a)
--- so we have to strip off function argument types as well
--- as the bit before the '=>' (which is always empty in interface files)
-removeContext (HsForAllTy tvs cxt ty) = HsForAllTy tvs [] (removeFuns ty)
-removeContext ty = removeFuns ty
-
-removeFuns (HsFunTy _ ty) = removeFuns ty
-removeFuns ty = ty
-
-
------------------------------------------------------
--- Loading Rules
------------------------------------------------------
-
-loadRules :: Module -> IfaceRules
- -> (Version, [RdrNameRuleDecl])
- -> RnM d (Version, IfaceRules)
-loadRules mod rule_bag (version, rules)
- | null rules || opt_IgnoreIfacePragmas
- = returnRn (version, rule_bag)
- | otherwise
- = setModuleRn mod $
- mapRn (loadRule mod) rules `thenRn` \ new_rules ->
- returnRn (version, rule_bag `unionBags` listToBag new_rules)
-
-loadRule :: Module -> RdrNameRuleDecl -> RnM d GatedDecl
--- "Gate" the rule simply by whether the rule variable is
--- needed. We can refine this later.
-loadRule mod decl@(IfaceRule _ _ var _ _ src_loc)
- = lookupOrigName var `thenRn` \ var_name ->
- returnRn (unitNameSet var_name, (mod, RuleD decl))
-
-loadBuiltinRules :: [(RdrName, CoreRule)] -> RnMG ()
-loadBuiltinRules builtin_rules
- = getIfacesRn `thenRn` \ ifaces ->
- mapRn loadBuiltinRule builtin_rules `thenRn` \ rule_decls ->
- setIfacesRn (ifaces { iRules = iRules ifaces `unionBags` listToBag rule_decls })
-
-loadBuiltinRule (var, rule)
- = lookupOrigName var `thenRn` \ var_name ->
- returnRn (unitNameSet var_name, (nameModule var_name, RuleD (IfaceRuleOut var rule)))
-
-
------------------------------------------------------
--- Loading Deprecations
------------------------------------------------------
-
-loadDeprec :: Module -> DeprecationEnv -> RdrNameDeprecation -> RnM d DeprecationEnv
-loadDeprec mod deprec_env (Deprecation (IEModuleContents _) txt _)
- = traceRn (text "module deprecation not yet implemented:" <+> ppr mod <> colon <+> ppr txt) `thenRn_`
- -- SUP: TEMPORARY HACK, ignoring module deprecations for now
- returnRn deprec_env
-
-loadDeprec mod deprec_env (Deprecation ie txt _)
- = setModuleRn mod $
- mapRn lookupOrigName (ieNames ie) `thenRn` \ names ->
- traceRn (text "loaded deprecation(s) for" <+> hcat (punctuate comma (map ppr names)) <> colon <+> ppr txt) `thenRn_`
- returnRn (extendNameEnvList deprec_env (zip names (repeat txt)))
+import List ( nub )
\end{code}
%*********************************************************
%* *
-\subsection{Getting in a declaration}
-%* *
-%*********************************************************
-
-\begin{code}
-importDecl :: Name -> RnMG ImportDeclResult
-
-data ImportDeclResult
- = AlreadySlurped
- | WiredIn
- | Deferred
- | HereItIs (Module, RdrNameHsDecl)
-
-importDecl name
- = -- Check if it was loaded before beginning this module
- checkAlreadyAvailable name `thenRn` \ done ->
- if done then
- returnRn AlreadySlurped
- else
-
- -- Check if we slurped it in while compiling this module
- getIfacesRn `thenRn` \ ifaces ->
- if name `elemNameSet` iSlurp ifaces then
- returnRn AlreadySlurped
- else
-
- -- Don't slurp in decls from this module's own interface file
- -- (Indeed, this shouldn't happen.)
- if isLocallyDefined name then
- addWarnRn (importDeclWarn name) `thenRn_`
- returnRn AlreadySlurped
- else
-
- -- When we find a wired-in name we must load its home
- -- module so that we find any instance decls lurking therein
- if name `elemNameEnv` wiredInThingEnv then
- loadHomeInterface doc name `thenRn_`
- returnRn WiredIn
-
- else getNonWiredInDecl name
- where
- doc = ptext SLIT("need home module for wired in thing") <+> ppr name
-
-getNonWiredInDecl :: Name -> RnMG ImportDeclResult
-getNonWiredInDecl needed_name
- = traceRn doc_str `thenRn_`
- loadHomeInterface doc_str needed_name `thenRn` \ ifaces ->
- case lookupNameEnv (iDecls ifaces) needed_name of
-
-{- OMIT DEFERRED STUFF FOR NOW, TILL GHCI WORKS
- Just (version, avail, is_tycon_name, decl@(_, TyClD (TyData DataType _ _ _ _ ncons _ _ _ _ _)))
- -- This case deals with deferred import of algebraic data types
-
- | not opt_NoPruneTyDecls
-
- && (opt_IgnoreIfacePragmas || ncons > 1)
- -- We only defer if imported interface pragmas are ingored
- -- or if it's not a product type.
- -- Sole reason: The wrapper for a strict function may need to look
- -- inside its arg, and hence need to see its arg type's constructors.
-
- && not (getUnique tycon_name `elem` cCallishTyKeys)
- -- Never defer ccall types; we have to unbox them,
- -- and importing them does no harm
-
-
- -> -- OK, so we're importing a deferrable data type
- if needed_name == tycon_name
- -- The needed_name is the TyCon of a data type decl
- -- Record that it's slurped, put it in the deferred set
- -- and don't return a declaration at all
- setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
- `addOneToNameSet` tycon_name})
- version (AvailTC needed_name [needed_name])) `thenRn_`
- returnRn Deferred
-
- else
- -- The needed name is a constructor of a data type decl,
- -- getting a constructor, so remove the TyCon from the deferred set
- -- (if it's there) and return the full declaration
- setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
- `delFromNameSet` tycon_name})
- version avail) `thenRn_`
- returnRn (HereItIs decl)
- where
- tycon_name = availName avail
--}
-
- Just (avail,_,decl)
- -> setIfacesRn (recordSlurp ifaces avail) `thenRn_`
- returnRn (HereItIs decl)
-
- Nothing
- -> addErrRn (getDeclErr needed_name) `thenRn_`
- returnRn AlreadySlurped
- where
- doc_str = ptext SLIT("need decl for") <+> ppr needed_name
-
-{- OMIT FOR NOW
-getDeferredDecls :: RnMG [(Module, RdrNameHsDecl)]
-getDeferredDecls
- = getIfacesRn `thenRn` \ ifaces ->
- let
- decls_map = iDecls ifaces
- deferred_names = nameSetToList (iDeferred ifaces)
- get_abstract_decl n = case lookupNameEnv decls_map n of
- Just (_, _, _, decl) -> decl
- in
- traceRn (sep [text "getDeferredDecls", nest 4 (fsep (map ppr deferred_names))]) `thenRn_`
- returnRn (map get_abstract_decl deferred_names)
--}
-\end{code}
-
-@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
-It behaves exactly as if the wired in decl were actually in an interface file.
-Specifically,
-\begin{itemize}
-\item if the wired-in name is a data type constructor or a data constructor,
- it brings in the type constructor and all the data constructors; and
- marks as ``occurrences'' any free vars of the data con.
-
-\item similarly for synonum type constructor
-
-\item if the wired-in name is another wired-in Id, it marks as ``occurrences''
- the free vars of the Id's type.
-
-\item it loads the interface file for the wired-in thing for the
- sole purpose of making sure that its instance declarations are available
-\end{itemize}
-All this is necessary so that we know all types that are ``in play'', so
-that we know just what instances to bring into scope.
-
-
-
-
-%*********************************************************
-%* *
\subsection{Getting what a module exports}
%* *
%*********************************************************
@getInterfaceExports@ is called only for directly-imported modules.
\begin{code}
-getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails)
+getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, [(ModuleName,Avails)])
getInterfaceExports mod_name from
= getHomeIfaceTableRn `thenRn` \ hit ->
case lookupModuleEnvByName hit mod_name of {
select (reqd, decl) (yes, no)
| isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no)
| otherwise = (yes, (reqd,decl) `consBag` no)
-
-lookupFixityRn :: Name -> RnMS Fixity
-lookupFixityRn name
- | isLocallyDefined name
- = getFixityEnv `thenRn` \ local_fix_env ->
- returnRn (lookupLocalFixity local_fix_env name)
-
- | otherwise -- Imported
- -- For imported names, we have to get their fixities by doing a loadHomeInterface,
- -- and consulting the Ifaces that comes back from that, because the interface
- -- file for the Name might not have been loaded yet. Why not? Suppose you import module A,
- -- which exports a function 'f', which is defined in module B. Then B isn't loaded
- -- right away (after all, it's possible that nothing from B will be used).
- -- When we come across a use of 'f', we need to know its fixity, and it's then,
- -- and only then, that we load B.hi. That is what's happening here.
- = getHomeIfaceTableRn `thenRn` \ hst ->
- case lookupFixityEnv hst name of {
- Just fixity -> returnRn fixity ;
- Nothing ->
-
- loadHomeInterface doc name `thenRn` \ ifaces ->
- returnRn (lookupFixityEnv (iPIT ifaces) name `orElse` defaultFixity)
- }
- where
- doc = ptext SLIT("Checking fixity for") <+> ppr name
\end{code}
So we'll get an early bale-out when compiling A if B's version changes.
\begin{code}
-mkImportExportInfo :: ModuleName -- Name of this module
- -> Avails -- Info about exports
- -> [ImportDecl n] -- The import decls
- -> RnMG ([ExportItem], -- Export info for iface file; sorted
- [ImportVersion Name]) -- Import info for iface file; sorted
- -- Both results are sorted into canonical order to
- -- reduce needless wobbling of interface files
-
-mkImportExportInfo this_mod export_avails exports
+mkImportInfo :: ModuleName -- Name of this module
+ -> [ImportDecl n] -- The import decls
+ -> RnMG [ImportVersion Name]
+
+mkImportInfo this_mod imports
= getIfacesRn `thenRn` \ ifaces ->
+ getHomeIfaceTableRn `thenRn` \ hit ->
let
import_all_mods :: [ModuleName]
-- Modules where we imported all the names
-- (apart from hiding some, perhaps)
- import_all_mods = nub [ m | ImportDecl m _ _ _ imp_list _ <- imports ]
+ import_all_mods = nub [ m | ImportDecl m _ _ _ imp_list _ <- imports,
+ import_all imp_list ]
import_all (Just (False, _)) = False -- Imports are specified explicitly
import_all other = True -- Everything is imported
mod_map = iImpModInfo ifaces
imp_names = iVSlurp ifaces
+ pit = iPIT ifaces
-- mv_map groups together all the things imported from a particular module.
mv_map :: ModuleEnv [Name]
- mv_map = foldr add_mv emptyFM imp_names
+ mv_map = foldr add_mv emptyModuleEnv imp_names
- add_mv (name, version) mv_map = addItem mv_map (nameModule name) name
+ add_mv name mv_map = addItem mv_map (nameModule name) name
-- Build the result list by adding info for each module.
-- For (a) a library module, we don't record it at all unless it contains orphans
so_far
| not opened -- We didn't even open the interface
- -> -- This happens when a module, Foo, that we explicitly imported has
+ = -- This happens when a module, Foo, that we explicitly imported has
-- 'import Baz' in its interface file, recording that Baz is below
-- Foo in the module dependency hierarchy. We want to propagate this
-- information. The Nothing says that we didn't even open the interface
- -- file but we must still propagate the dependeny info.
+ -- file but we must still propagate the dependency info.
-- The module in question must be a local module (in the same package)
go_for_it NothingAtAll
| is_lib_module && not has_orphans
- -> so_far
+ = so_far
- | is_lib_module -- Record the module version only
- -> go_for_it (Everything mod_vers)
+ | is_lib_module -- Record the module version only
+ = go_for_it (Everything module_vers)
- | otherwise
- -> go_for_it (mk_whats_imported mod mod_vers)
+ | otherwise
+ = go_for_it whats_imported
- where
-
where
go_for_it exports = (mod_name, has_orphans, is_boot, exports) : so_far
- mod_iface = lookupIface hit pit mod_name
+ mod_iface = lookupTableByModName hit pit mod_name `orElse` panic "mkImportInfo"
mod = mi_module mod_iface
is_lib_module = not (isModuleInThisPackage mod)
version_info = mi_version mod_iface
version_env = vers_decls version_info
+ module_vers = vers_module version_info
- whats_imported = Specifically mod_vers export_vers import_items
+ whats_imported = Specifically module_vers
+ export_vers import_items
(vers_rules version_info)
import_items = [(n,v) | n <- lookupWithDefaultModuleEnv mv_map [] mod,
- let v = lookupNameEnv version_env `orElse`
+ let v = lookupNameEnv version_env n `orElse`
pprPanic "mk_whats_imported" (ppr n)
]
- export_vers | moduleName mod `elem` import_all_mods = Just (vers_exports version_info)
- | otherwise = Nothing
+ export_vers | moduleName mod `elem` import_all_mods
+ = Just (vers_exports version_info)
+ | otherwise
+ = Nothing
import_info = foldFM mk_imp_info [] mod_map
-
- -- Sort exports into groups by module
- export_fm :: FiniteMap Module [RdrAvailInfo]
- export_fm = foldr insert emptyFM export_avails
-
- insert avail efm = addItem efm (nameModule (availName avail))
- avail
-
- export_info = fmToList export_fm
in
traceRn (text "Modules in Ifaces: " <+> fsep (map ppr (keysFM mod_map))) `thenRn_`
- returnRn (export_info, import_info)
+ returnRn import_info
addItem :: ModuleEnv [a] -> Module -> a -> ModuleEnv [a]
-addItem fm mod x = plusModuleEnv_C add_item fm mod [x]
+addItem fm mod x = extendModuleEnv_C add_item fm mod [x]
where
add_item xs _ = x:xs
\end{code}
+%*********************************************************
+%* *
+\subsection{Slurping declarations}
+%* *
+%*********************************************************
+
+\begin{code}
+-------------------------------------------------------
+slurpImpDecls source_fvs
+ = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`
+
+ -- The current slurped-set records all local things
+ getSlurped `thenRn` \ source_binders ->
+ slurpSourceRefs source_binders source_fvs `thenRn` \ (decls, needed) ->
+
+ -- Then get everything else
+ closeDecls decls needed `thenRn` \ decls1 ->
+
+ -- Finally, get any deferred data type decls
+ slurpDeferredDecls decls1 `thenRn` \ final_decls ->
+
+ returnRn final_decls
+
+
+-------------------------------------------------------
+slurpSourceRefs :: NameSet -- Variables defined in source
+ -> FreeVars -- Variables referenced in source
+ -> RnMG ([RenamedHsDecl],
+ FreeVars) -- Un-satisfied needs
+-- The declaration (and hence home module) of each gate has
+-- already been loaded
+
+slurpSourceRefs source_binders source_fvs
+ = go_outer [] -- Accumulating decls
+ emptyFVs -- Unsatisfied needs
+ emptyFVs -- Accumulating gates
+ (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet
+ where
+ -- The outer loop repeatedly slurps the decls for the current gates
+ -- and the instance decls
+
+ -- The outer loop is needed because consider
+ -- instance Foo a => Baz (Maybe a) where ...
+ -- It may be that @Baz@ and @Maybe@ are used in the source module,
+ -- but not @Foo@; so we need to chase @Foo@ too.
+ --
+ -- We also need to follow superclass refs. In particular, 'chasing @Foo@' must
+ -- include actually getting in Foo's class decl
+ -- class Wib a => Foo a where ..
+ -- so that its superclasses are discovered. The point is that Wib is a gate too.
+ -- We do this for tycons too, so that we look through type synonyms.
+
+ go_outer decls fvs all_gates []
+ = returnRn (decls, fvs)
+
+ go_outer decls fvs all_gates refs -- refs are not necessarily slurped yet
+ = traceRn (text "go_outer" <+> ppr refs) `thenRn_`
+ foldlRn go_inner (decls, fvs, emptyFVs) refs `thenRn` \ (decls1, fvs1, gates1) ->
+ getImportedInstDecls (all_gates `plusFV` gates1) `thenRn` \ inst_decls ->
+ rnInstDecls decls1 fvs1 gates1 inst_decls `thenRn` \ (decls2, fvs2, gates2) ->
+ go_outer decls2 fvs2 (all_gates `plusFV` gates2)
+ (nameSetToList (gates2 `minusNameSet` all_gates))
+ -- Knock out the all_gates because even if we don't slurp any new
+ -- decls we can get some apparently-new gates from wired-in names
+
+ go_inner (decls, fvs, gates) wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ AlreadySlurped -> returnRn (decls, fvs, gates)
+ WiredIn -> returnRn (decls, fvs, gates `plusFV` getWiredInGates wanted_name)
+ Deferred -> returnRn (decls, fvs, gates `addOneFV` wanted_name) -- It's a type constructor
+
+ HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (TyClD new_decl : decls,
+ fvs1 `plusFV` fvs,
+ gates `plusFV` getGates source_fvs new_decl)
+
+rnInstDecls decls fvs gates []
+ = returnRn (decls, fvs, gates)
+rnInstDecls decls fvs gates (d:ds)
+ = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnInstDecls (new_decl:decls)
+ (fvs1 `plusFV` fvs)
+ (gates `plusFV` getInstDeclGates new_decl)
+ ds
+\end{code}
+
+
+\begin{code}
+-------------------------------------------------------
+-- closeDecls keeps going until the free-var set is empty
+closeDecls decls needed
+ | not (isEmptyFVs needed)
+ = slurpDecls decls needed `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+
+ | otherwise
+ = getImportedRules `thenRn` \ rule_decls ->
+ case rule_decls of
+ [] -> returnRn decls -- No new rules, so we are done
+ other -> rnIfaceDecls decls emptyFVs rule_decls `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+
+
+-------------------------------------------------------
+-- Augment decls with any decls needed by needed.
+-- Return also free vars of the new decls (only)
+slurpDecls decls needed
+ = go decls emptyFVs (nameSetToList needed)
+ where
+ go decls fvs [] = returnRn (decls, fvs)
+ go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->
+ go decls1 fvs1 refs
+
+-------------------------------------------------------
+slurpDecl decls fvs wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ -- Found a declaration... rename it
+ HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (TyClD new_decl:decls, fvs1 `plusFV` fvs)
+
+ -- No declaration... (wired in thing, or deferred, or already slurped)
+ other -> returnRn (decls, fvs)
+
+
+-------------------------------------------------------
+rnIfaceDecls :: [RenamedHsDecl] -> FreeVars
+ -> [(Module, RdrNameHsDecl)]
+ -> RnM d ([RenamedHsDecl], FreeVars)
+rnIfaceDecls decls fvs [] = returnRn (decls, fvs)
+rnIfaceDecls decls fvs (d:ds) = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnIfaceDecls (new_decl:decls) (fvs1 `plusFV` fvs) ds
+
+rnIfaceDecl (mod, decl) = initIfaceRnMS mod (rnDecl decl)
+rnIfaceTyClDecl (mod, decl) = initIfaceRnMS mod (rnTyClDecl decl) `thenRn` \ decl' ->
+ returnRn (decl', tyClDeclFVs decl')
+\end{code}
+
+
\begin{code}
getSlurped
= getIfacesRn `thenRn` \ ifaces ->
\end{code}
+
%*********************************************************
-%* *
-\subsection{Getting binders out of a declaration}
-%* *
+%* *
+\subsection{Deferred declarations}
+%* *
%*********************************************************
-@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
-It's used for both source code (from @availsFromDecl@) and interface files
-(from @loadDecl@).
+The idea of deferred declarations is this. Suppose we have a function
+ f :: T -> Int
+ data T = T1 A | T2 B
+ data A = A1 X | A2 Y
+ data B = B1 P | B2 Q
+Then we don't want to load T and all its constructors, and all
+the types those constructors refer to, and all the types *those*
+constructors refer to, and so on. That might mean loading many more
+interface files than is really necessary. So we 'defer' loading T.
+
+But f might be strict, and the calling convention for evaluating
+values of type T depends on how many constructors T has, so
+we do need to load T, but not the full details of the type T.
+So we load the full decl for T, but only skeleton decls for A and B:
+ f :: T -> Int
+ data T = {- 2 constructors -}
+
+Whether all this is worth it is moot.
+
+\begin{code}
+slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl]
+slurpDeferredDecls decls = returnRn decls
+
+{- OMIT FOR NOW
+slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl]
+slurpDeferredDecls decls
+ = getDeferredDecls `thenRn` \ def_decls ->
+ rnIfaceDecls decls emptyFVs (map stripDecl def_decls) `thenRn` \ (decls1, fvs) ->
+ ASSERT( isEmptyFVs fvs )
+ returnRn decls1
+
+stripDecl (mod, TyClD (TyData dt _ tc tvs _ nconstrs _ loc name1 name2))
+ = (mod, TyClD (TyData dt [] tc tvs [] nconstrs Nothing loc
+ name1 name2))
+ -- Nuke the context and constructors
+ -- But retain the *number* of constructors!
+ -- Also the tvs will have kinds on them.
+-}
+\end{code}
+
-It doesn't deal with source-code specific things: @ValD@, @DefD@. They
-are handled by the sourc-code specific stuff in @RnNames@.
+%*********************************************************
+%* *
+\subsection{Extracting the `gates'}
+%* *
+%*********************************************************
+
+When we import a declaration like
+\begin{verbatim}
+ data T = T1 Wibble | T2 Wobble
+\end{verbatim}
+we don't want to treat @Wibble@ and @Wobble@ as gates
+{\em unless} @T1@, @T2@ respectively are mentioned by the user program.
+If only @T@ is mentioned
+we want only @T@ to be a gate;
+that way we don't suck in useless instance
+decls for (say) @Eq Wibble@, when they can't possibly be useful.
+
+@getGates@ takes a newly imported (and renamed) decl, and the free
+vars of the source program, and extracts from the decl the gate names.
\begin{code}
-getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function
- -> RdrNameHsDecl
- -> RnM d (Maybe AvailInfo)
+getGates source_fvs (IfaceSig _ ty _ _)
+ = extractHsTyNames ty
+
+getGates source_fvs (ClassDecl ctxt cls tvs _ sigs _ _ _ )
+ = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` cls)
+ `plusFV` maybe_double
+ where
+ get (ClassOpSig n _ ty _)
+ | n `elemNameSet` source_fvs = extractHsTyNames ty
+ | otherwise = emptyFVs
+
+ -- If we load any numeric class that doesn't have
+ -- Int as an instance, add Double to the gates.
+ -- This takes account of the fact that Double might be needed for
+ -- defaulting, but we don't want to load Double (and all its baggage)
+ -- if the more exotic classes aren't used at all.
+ maybe_double | nameUnique cls `elem` fractionalClassKeys
+ = unitFV (getName doubleTyCon)
+ | otherwise
+ = emptyFVs
+
+getGates source_fvs (TySynonym tycon tvs ty _)
+ = delListFromNameSet (extractHsTyNames ty)
+ (hsTyVarNames tvs)
+ -- A type synonym type constructor isn't a "gate" for instance decls
+
+getGates source_fvs (TyData _ ctxt tycon tvs cons _ _ _ _ _)
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` tycon
+ where
+ get (ConDecl n _ tvs ctxt details _)
+ | n `elemNameSet` source_fvs
+ -- If the constructor is method, get fvs from all its fields
+ = delListFromNameSet (get_details details `plusFV`
+ extractHsCtxtTyNames ctxt)
+ (hsTyVarNames tvs)
+ get (ConDecl n _ tvs ctxt (RecCon fields) _)
+ -- Even if the constructor isn't mentioned, the fields
+ -- might be, as selectors. They can't mention existentially
+ -- bound tyvars (typechecker checks for that) so no need for
+ -- the deleteListFromNameSet part
+ = foldr (plusFV . get_field) emptyFVs fields
+
+ get other_con = emptyFVs
-getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ _ src_loc _ _))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- getConFieldNames new_name condecls `thenRn` \ sub_names ->
- returnRn (Just (AvailTC tycon_name (tycon_name : nub sub_names)))
- -- The "nub" is because getConFieldNames can legitimately return duplicates,
- -- when a record declaration has the same field in multiple constructors
+ get_details (VanillaCon tys) = plusFVs (map get_bang tys)
+ get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2
+ get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields]
-getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- returnRn (Just (AvailTC tycon_name [tycon_name]))
+ get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t
+ | otherwise = emptyFVs
-getDeclBinders new_name (TyClD (ClassDecl _ cname _ _ sigs _ _ _ src_loc))
- = new_name cname src_loc `thenRn` \ class_name ->
+ get_bang bty = extractHsTyNames (getBangType bty)
+\end{code}
- -- Record the names for the class ops
- let
- -- just want class-op sigs
- op_sigs = filter isClassOpSig sigs
- in
- mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names ->
+@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@
+rather than a declaration.
+
+\begin{code}
+getWiredInGates :: Name -> FreeVars
+getWiredInGates name -- No classes are wired in
+ = case lookupNameEnv wiredInThingEnv name of
+ Just (AnId the_id) -> getWiredInGates_s (namesOfType (idType the_id))
- returnRn (Just (AvailTC class_name (class_name : sub_names)))
+ Just (ATyCon tc)
+ | isSynTyCon tc
+ -> getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars))
+ where
+ (tyvars,ty) = getSynTyConDefn tc
+
+ other -> unitFV name
+
+getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names)
+\end{code}
+
+\begin{code}
+getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty
+getInstDeclGates other = emptyFVs
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Getting in a declaration}
+%* *
+%*********************************************************
-getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
- = new_name var src_loc `thenRn` \ var_name ->
- returnRn (Just (Avail var_name))
+\begin{code}
+importDecl :: Name -> RnMG ImportDeclResult
-getDeclBinders new_name (FixD _) = returnRn Nothing
-getDeclBinders new_name (DeprecD _) = returnRn Nothing
+data ImportDeclResult
+ = AlreadySlurped
+ | WiredIn
+ | Deferred
+ | HereItIs (Module, RdrNameTyClDecl)
- -- foreign declarations
-getDeclBinders new_name (ForD (ForeignDecl nm kind _ dyn _ loc))
- | binds_haskell_name kind dyn
- = new_name nm loc `thenRn` \ name ->
- returnRn (Just (Avail name))
+importDecl name
+ = -- Check if it was loaded before beginning this module
+ checkAlreadyAvailable name `thenRn` \ done ->
+ if done then
+ returnRn AlreadySlurped
+ else
- | otherwise -- a foreign export
- = lookupOrigName nm `thenRn_`
- returnRn Nothing
+ -- Check if we slurped it in while compiling this module
+ getIfacesRn `thenRn` \ ifaces ->
+ if name `elemNameSet` iSlurp ifaces then
+ returnRn AlreadySlurped
+ else
-getDeclBinders new_name (DefD _) = returnRn Nothing
-getDeclBinders new_name (InstD _) = returnRn Nothing
-getDeclBinders new_name (RuleD _) = returnRn Nothing
+ -- Don't slurp in decls from this module's own interface file
+ -- (Indeed, this shouldn't happen.)
+ if isLocallyDefined name then
+ addWarnRn (importDeclWarn name) `thenRn_`
+ returnRn AlreadySlurped
+ else
-binds_haskell_name (FoImport _) _ = True
-binds_haskell_name FoLabel _ = True
-binds_haskell_name FoExport ext_nm = isDynamicExtName ext_nm
+ -- When we find a wired-in name we must load its home
+ -- module so that we find any instance decls lurking therein
+ if name `elemNameEnv` wiredInThingEnv then
+ loadHomeInterface doc name `thenRn_`
+ returnRn WiredIn
-----------------
-getConFieldNames new_name (ConDecl con _ _ _ (RecCon fielddecls) src_loc : rest)
- = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (cfs ++ ns)
+ else getNonWiredInDecl name
where
- fields = concat (map fst fielddecls)
+ doc = ptext SLIT("need home module for wired in thing") <+> ppr name
-getConFieldNames new_name (ConDecl con _ _ _ condecl src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n : ns)
+getNonWiredInDecl :: Name -> RnMG ImportDeclResult
+getNonWiredInDecl needed_name
+ = traceRn doc_str `thenRn_`
+ loadHomeInterface doc_str needed_name `thenRn` \ ifaces ->
+ case lookupNameEnv (iDecls ifaces) needed_name of
-getConFieldNames new_name [] = returnRn []
+{- OMIT DEFERRED STUFF FOR NOW, TILL GHCI WORKS
+ Just (version, avail, is_tycon_name, decl@(_, TyClD (TyData DataType _ _ _ _ ncons _ _ _ _)))
+ -- This case deals with deferred import of algebraic data types
-getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
-\end{code}
+ | not opt_NoPruneTyDecls
-@getDeclSysBinders@ gets the implicit binders introduced by a decl.
-A the moment that's just the tycon and datacon that come with a class decl.
-They aren't returned by @getDeclBinders@ because they aren't in scope;
-but they {\em should} be put into the @DeclsMap@ of this module.
+ && (opt_IgnoreIfacePragmas || ncons > 1)
+ -- We only defer if imported interface pragmas are ingored
+ -- or if it's not a product type.
+ -- Sole reason: The wrapper for a strict function may need to look
+ -- inside its arg, and hence need to see its arg type's constructors.
-Note that this excludes the default-method names of a class decl,
-and the dict fun of an instance decl, because both of these have
-bindings of their own elsewhere.
+ && not (getUnique tycon_name `elem` cCallishTyKeys)
+ -- Never defer ccall types; we have to unbox them,
+ -- and importing them does no harm
-\begin{code}
-getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ _ sigs _ _ names
- src_loc))
- = sequenceRn [new_name n src_loc | n <- names]
-getDeclSysBinders new_name (TyClD (TyData _ _ _ _ cons _ _ _ _ _ _))
- = sequenceRn [new_name wkr_name src_loc | ConDecl _ wkr_name _ _ _ src_loc <- cons]
+ -> -- OK, so we're importing a deferrable data type
+ if needed_name == tycon_name
+ -- The needed_name is the TyCon of a data type decl
+ -- Record that it's slurped, put it in the deferred set
+ -- and don't return a declaration at all
+ setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
+ `addOneToNameSet` tycon_name})
+ version (AvailTC needed_name [needed_name])) `thenRn_`
+ returnRn Deferred
+
+ else
+ -- The needed name is a constructor of a data type decl,
+ -- getting a constructor, so remove the TyCon from the deferred set
+ -- (if it's there) and return the full declaration
+ setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
+ `delFromNameSet` tycon_name})
+ version avail) `thenRn_`
+ returnRn (HereItIs decl)
+ where
+ tycon_name = availName avail
+-}
+
+ Just (avail,_,decl)
+ -> setIfacesRn (recordSlurp ifaces avail) `thenRn_`
+ returnRn (HereItIs decl)
-getDeclSysBinders new_name other_decl
- = returnRn []
+ Nothing
+ -> addErrRn (getDeclErr needed_name) `thenRn_`
+ returnRn AlreadySlurped
+ where
+ doc_str = ptext SLIT("need decl for") <+> ppr needed_name
+
+{- OMIT FOR NOW
+getDeferredDecls :: RnMG [(Module, RdrNameHsDecl)]
+getDeferredDecls
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ decls_map = iDecls ifaces
+ deferred_names = nameSetToList (iDeferred ifaces)
+ get_abstract_decl n = case lookupNameEnv decls_map n of
+ Just (_, _, _, decl) -> decl
+ in
+ traceRn (sep [text "getDeferredDecls", nest 4 (fsep (map ppr deferred_names))]) `thenRn_`
+ returnRn (map get_abstract_decl deferred_names)
+-}
\end{code}
-%*********************************************************
+@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
+It behaves exactly as if the wired in decl were actually in an interface file.
+Specifically,
+\begin{itemize}
+\item if the wired-in name is a data type constructor or a data constructor,
+ it brings in the type constructor and all the data constructors; and
+ marks as ``occurrences'' any free vars of the data con.
+
+\item similarly for synonum type constructor
+
+\item if the wired-in name is another wired-in Id, it marks as ``occurrences''
+ the free vars of the Id's type.
+
+\item it loads the interface file for the wired-in thing for the
+ sole purpose of making sure that its instance declarations are available
+\end{itemize}
+All this is necessary so that we know all types that are ``in play'', so
+that we know just what instances to bring into scope.
+
+
+%********************************************************
%* *
-\subsection{Reading an interface file}
+\subsection{Checking usage information}
%* *
-%*********************************************************
+%********************************************************
+
+@recompileRequired@ is called from the HscMain. It checks whether
+a recompilation is required. It needs access to the persistent state,
+finder, etc, because it may have to load lots of interface files to
+check their versions.
\begin{code}
-findAndReadIface :: SDoc -> ModuleName
- -> IsBootInterface -- True <=> Look for a .hi-boot file
- -- False <=> Look for .hi file
- -> RnM d (Either Message (Module, ParsedIface))
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-
-findAndReadIface doc_str mod_name hi_boot_file
- = traceRn trace_msg `thenRn_`
- -- we keep two maps for interface files,
- -- one for 'normal' ones, the other for .hi-boot files,
- -- hence the need to signal which kind we're interested.
-
- getFinderRn `thenRn` \ finder ->
- ioToRnM (finder mod_name) `thenRn` \ maybe_found ->
-
- case maybe_found of
- Just (mod,locn)
- | hi_boot_file -> readIface mod (hi_file locn ++ "-hi-boot")
- | otherwise -> readIface mod (hi_file locn)
-
- -- Can't find it
- other -> traceRn (ptext SLIT("...not found")) `thenRn_`
- returnRn (Left (noIfaceErr mod_name hi_boot_file))
+type RecompileRequired = Bool
+upToDate = False -- Recompile not required
+outOfDate = True -- Recompile required
+
+recompileRequired :: Module
+ -> Bool -- Source unchanged
+ -> Maybe ModIface -- Old interface, if any
+ -> RnMG RecompileRequired
+recompileRequired mod source_unchanged maybe_iface
+ = traceRn (text "Considering whether compilation is required for" <+> ppr mod <> colon) `thenRn_`
+
+ -- CHECK WHETHER THE SOURCE HAS CHANGED
+ if not source_unchanged then
+ traceRn (nest 4 (text "Source file changed or recompilation check turned off")) `thenRn_`
+ returnRn outOfDate
+ else
- where
- trace_msg = sep [hsep [ptext SLIT("Reading"),
- if hi_boot_file then ptext SLIT("[boot]") else empty,
- ptext SLIT("interface for"),
- ppr mod_name <> semi],
- nest 4 (ptext SLIT("reason:") <+> doc_str)]
+ -- CHECK WHETHER WE HAVE AN OLD IFACE
+ case maybe_iface of
+ Nothing -> traceRn (nest 4 (ptext SLIT("No old interface file"))) `thenRn_`
+ returnRn outOfDate ;
+
+ Just iface -> -- Source code unchanged and no errors yet... carry on
+ checkList [checkModUsage u | u <- mi_usages iface]
+
+checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired
+checkList [] = returnRn upToDate
+checkList (check:checks) = check `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate
+ else
+ checkList checks
\end{code}
+
+\begin{code}
+checkModUsage :: ImportVersion Name -> RnMG RecompileRequired
+-- Given the usage information extracted from the old
+-- M.hi file for the module being compiled, figure out
+-- whether M needs to be recompiled.
+
+checkModUsage (mod_name, _, _, NothingAtAll)
+ -- If CurrentModule.hi contains
+ -- import Foo :: ;
+ -- then that simply records that Foo lies below CurrentModule in the
+ -- hierarchy, but CurrentModule doesn't depend in any way on Foo.
+ -- In this case we don't even want to open Foo's interface.
+ = up_to_date (ptext SLIT("Nothing used from:") <+> ppr mod_name)
+
+checkModUsage (mod_name, _, _, whats_imported)
+ = tryLoadInterface doc_str mod_name ImportBySystem `thenRn` \ (ifaces, maybe_err) ->
+ case maybe_err of {
+ Just err -> out_of_date (sep [ptext SLIT("Can't find version number for module"),
+ ppr mod_name]) ;
+ -- Couldn't find or parse a module mentioned in the
+ -- old interface file. Don't complain -- it might just be that
+ -- the current module doesn't need that import and it's been deleted
+
+ Nothing ->
+
+ getHomeIfaceTableRn `thenRn` \ hit ->
+ let
+ mod_details = lookupTableByModName hit (iPIT ifaces) mod_name
+ `orElse` panic "checkModUsage"
+ new_vers = mi_version mod_details
+ new_decl_vers = vers_decls new_vers
+ in
+ case whats_imported of { -- NothingAtAll dealt with earlier
-@readIface@ tries just the one file.
+ Everything old_mod_vers -> checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile ->
+ if recompile then
+ out_of_date (ptext SLIT("...and I needed the whole module"))
+ else
+ returnRn upToDate ;
-\begin{code}
-readIface :: Module -> String -> RnM d (Either Message (Module, ParsedIface))
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-readIface wanted_mod file_path
- = traceRn (ptext SLIT("...reading from") <+> text file_path) `thenRn_`
- ioToRnM (hGetStringBuffer False file_path) `thenRn` \ read_result ->
- case read_result of
- Right contents ->
- case parseIface contents
- PState{ bol = 0#, atbol = 1#,
- context = [],
- glasgow_exts = 1#,
- loc = mkSrcLoc (mkFastString file_path) 1 } of
- POk _ (PIface iface) ->
- warnCheckRn (wanted_mod == read_mod)
- (hiModuleNameMismatchWarn wanted_mod read_mod) `thenRn_`
- returnRn (Right (wanted_mod, iface))
- where
- read_mod = pi_mod iface
-
- PFailed err -> bale_out err
- parse_result -> bale_out empty
- -- This last case can happen if the interface file is (say) empty
- -- in which case the parser thinks it looks like an IdInfo or
- -- something like that. Just an artefact of the fact that the
- -- parser is used for several purposes at once.
-
- Left io_err -> bale_out (text (show io_err))
+ Specifically old_mod_vers maybe_old_export_vers old_decl_vers old_rule_vers ->
+
+ -- CHECK MODULE
+ checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile ->
+ if not recompile then
+ returnRn upToDate
+ else
+
+ -- CHECK EXPORT LIST
+ if checkExportList maybe_old_export_vers new_vers then
+ out_of_date (ptext SLIT("Export list changed"))
+ else
+
+ -- CHECK RULES
+ if old_rule_vers /= vers_rules new_vers then
+ out_of_date (ptext SLIT("Rules changed"))
+ else
+
+ -- CHECK ITEMS ONE BY ONE
+ checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate -- This one failed, so just bail out now
+ else
+ up_to_date (ptext SLIT("...but the bits I use haven't."))
+
+ }}
where
- bale_out err = returnRn (Left (badIfaceFile file_path err))
+ doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
+
+------------------------
+checkModuleVersion old_mod_vers new_vers
+ | vers_module new_vers == old_mod_vers
+ = up_to_date (ptext SLIT("Module version unchanged"))
+
+ | otherwise
+ = out_of_date (ptext SLIT("Module version has changed"))
+
+------------------------
+checkExportList Nothing new_vers = upToDate
+checkExportList (Just v) new_vers = v /= vers_exports new_vers
+
+------------------------
+checkEntityUsage new_vers (name,old_vers)
+ = case lookupNameEnv new_vers name of
+
+ Nothing -> -- We used it before, but it ain't there now
+ out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
+
+ Just new_vers -- It's there, but is it up to date?
+ | new_vers == old_vers -> returnRn upToDate
+ | otherwise -> out_of_date (sep [ptext SLIT("Out of date:"), ppr name])
+
+up_to_date msg = traceRn msg `thenRn_` returnRn upToDate
+out_of_date msg = traceRn msg `thenRn_` returnRn outOfDate
\end{code}
+
%*********************************************************
%* *
\subsection{Errors}
%*********************************************************
\begin{code}
-noIfaceErr mod_name boot_file
- = ptext SLIT("Could not find interface file for") <+> quotes (ppr mod_name)
- -- We used to print the search path, but we can't do that
- -- now, becuase it's hidden inside the finder.
- -- Maybe the finder should expose more functions.
-
-badIfaceFile file err
- = vcat [ptext SLIT("Bad interface file:") <+> text file,
- nest 4 err]
-
getDeclErr name
= vcat [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name),
ptext SLIT("from module") <+> quotes (ppr (nameModule name))
"(possible cause: module name clashes with interface file already in scope.)")
] $$
hsep [ptext SLIT("name:"), quotes (ppr name)]
-
-warnRedundantSourceImport mod_name
- = ptext SLIT("Unnecessary {- SOURCE -} in the import of module")
- <+> quotes (ppr mod_name)
-
-hiModuleNameMismatchWarn :: Module -> ModuleName -> Message
-hiModuleNameMismatchWarn requested_mod read_mod =
- hsep [ ptext SLIT("Something is amiss; requested module name")
- , ppr (moduleName requested_mod)
- , ptext SLIT("differs from name found in the interface file")
- , ppr read_mod
- ]
-
\end{code}