X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnBinds.lhs;h=871041652a6b93c41a382b98704fb4317bfc9b36;hb=115f0fae2f782836550a9419f739fd29c09e4f1b;hp=ced653a84e8a67973618dbb3fd83b637e2020fb3;hpb=f7ecf7234c224489be8a5e63fced903b655d92ee;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnBinds.lhs b/ghc/compiler/rename/RnBinds.lhs index ced653a..8710416 100644 --- a/ghc/compiler/rename/RnBinds.lhs +++ b/ghc/compiler/rename/RnBinds.lhs @@ -1,5 +1,5 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[RnBinds]{Renaming and dependency analysis of bindings} @@ -9,37 +9,33 @@ type-synonym declarations; those cannot be done at this stage because they may be affected by renaming (which isn't fully worked out yet). \begin{code} -#include "HsVersions.h" - module RnBinds ( - rnTopBinds, - rnMethodBinds, - rnBinds, - SYN_IE(FreeVars), - SYN_IE(DefinedVars) + rnTopMonoBinds, rnMonoBinds, rnMonoBindsAndThen, + rnMethodBinds, renameSigs, checkSigs, unknownSigErr ) where -IMP_Ubiq() -IMPORT_DELOOPER(RnLoop) -- break the RnPass/RnExpr/RnBinds loops +#include "HsVersions.h" + import HsSyn -import HsPragmas ( isNoGenPragmas, noGenPragmas ) +import HsBinds ( eqHsSig, hsSigDoc ) import RdrHsSyn import RnHsSyn -import RnMonad -import RnExpr ( rnMatch, rnGRHSsAndBinds, rnPat, checkPrecMatch ) - -import CmdLineOpts ( opt_SigsRequired ) -import Digraph ( stronglyConnComp ) -import ErrUtils ( addErrLoc, addShortErrLocLine ) -import Name ( getLocalName, RdrName ) -import Maybes ( catMaybes ) ---import PprStyle--ToDo:rm -import Pretty -import UniqSet ( emptyUniqSet, unitUniqSet, mkUniqSet, - unionUniqSets, unionManyUniqSets, - elementOfUniqSet, uniqSetToList, SYN_IE(UniqSet) ) -import Util ( thenCmp, isIn, removeDups, panic, panic#, assertPanic ) +import TcRnMonad +import RnTypes ( rnHsSigType, rnHsType, rnPat ) +import RnExpr ( rnMatch, rnGRHSs, checkPrecMatch ) +import RnEnv ( bindLocatedLocalsRn, lookupBndrRn, lookupInstDeclBndr, + lookupSigOccRn, bindPatSigTyVars, bindLocalFixities, + warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn, + ) +import CmdLineOpts ( DynFlag(..) ) +import Digraph ( SCC(..), stronglyConnComp ) +import Name ( Name, nameOccName, nameSrcLoc ) +import NameSet +import RdrName ( RdrName, rdrNameOcc ) +import BasicTypes ( RecFlag(..) ) +import List ( unzip4 ) +import Outputable \end{code} -- ToDo: Put the annotations into the monad, so that they arrive in the proper @@ -64,30 +60,17 @@ This is precisely what the function @rnBinds@ does. ToDo: deal with case where a single monobinds binds the same variable twice. -Sets of variable names are represented as sets explicitly, rather than lists. - -\begin{code} -type DefinedVars = UniqSet RnName -type FreeVars = UniqSet RnName -\end{code} - -i.e., binders. - The vertag tag is a unique @Int@; the tags only need to be unique within one @MonoBinds@, so that unique-Int plumbing is done explicitly (heavy monad machinery not needed). -\begin{code} -type VertexTag = Int -type Cycle = [VertexTag] -type Edge = (VertexTag, VertexTag) -\end{code} %************************************************************************ %* * %* naming conventions * %* * %************************************************************************ + \subsection[name-conventions]{Name conventions} The basic algorithm involves walking over the tree and returning a tuple @@ -114,6 +97,7 @@ a set of variables free in @Exp@ is written @fvExp@ %* analysing polymorphic bindings (HsBinds, Bind, MonoBinds) * %* * %************************************************************************ + \subsubsection[dep-HsBinds]{Polymorphic bindings} Non-recursive expressions are reconstructed without any changes at top @@ -122,7 +106,7 @@ However, non-recursive expressions are currently not expected as \Haskell{} programs, and this code should not be executed. Monomorphic bindings contain information that is returned in a tuple -(a @FlatMonoBindsInfo@) containing: +(a @FlatMonoBinds@) containing: \begin{enumerate} \item @@ -154,346 +138,315 @@ instance declarations. It expects only to see @FunMonoBind@s, and it expects the global environment to contain bindings for the binders (which are all class operations). -\begin{code} -rnTopBinds :: RdrNameHsBinds -> RnM_Fixes s RenamedHsBinds -rnMethodBinds :: RnName{-class-} -> RdrNameMonoBinds -> RnM_Fixes s RenamedMonoBinds -rnBinds :: RdrNameHsBinds -> RnM_Fixes s (RenamedHsBinds, FreeVars, [RnName]) - -rnTopBinds EmptyBinds = returnRn EmptyBinds -rnTopBinds (SingleBind (RecBind bind)) = rnTopMonoBinds bind [] -rnTopBinds (BindWith (RecBind bind) sigs) = rnTopMonoBinds bind sigs - -- the parser doesn't produce other forms - --- ******************************************************************** - -rnMethodBinds class_name EmptyMonoBinds = returnRn EmptyMonoBinds - -rnMethodBinds class_name (AndMonoBinds mb1 mb2) - = andRn AndMonoBinds (rnMethodBinds class_name mb1) - (rnMethodBinds class_name mb2) - -rnMethodBinds class_name (FunMonoBind occname inf matches locn) - = pushSrcLocRn locn $ - lookupClassOp class_name occname `thenRn` \ op_name -> - mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, _) -> - mapRn (checkPrecMatch inf op_name) new_matches `thenRn_` - returnRn (FunMonoBind op_name inf new_matches locn) - -rnMethodBinds class_name (PatMonoBind (VarPatIn occname) grhss_and_binds locn) - = pushSrcLocRn locn $ - lookupClassOp class_name occname `thenRn` \ op_name -> - rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', _) -> - returnRn (PatMonoBind (VarPatIn op_name) grhss_and_binds' locn) +%************************************************************************ +%* * +\subsubsection{ Top-level bindings} +%* * +%************************************************************************ --- Can't handle method pattern-bindings which bind multiple methods. -rnMethodBinds _ mbind@(PatMonoBind other_pat _ locn) - = failButContinueRn EmptyMonoBinds (methodBindErr mbind locn) +@rnTopMonoBinds@ assumes that the environment already +contains bindings for the binders of this particular binding. --- ******************************************************************** +\begin{code} +rnTopMonoBinds :: RdrNameMonoBinds + -> [RdrNameSig] + -> RnM (RenamedHsBinds, FreeVars) + +-- Assumes the binders of the binding are in scope already +-- Very like rnMonoBinds, but checks for missing signatures too + +rnTopMonoBinds mbinds sigs + = bindPatSigTyVars (collectSigTysFromMonoBinds mbinds) $ + -- Hmm; by analogy with Ids, this doesn't look right + + renameSigs sigs `thenM` \ siglist -> + rn_mono_binds siglist mbinds `thenM` \ (binders, final_binds, bind_fvs) -> + checkSigs okBindSig binders siglist `thenM_` + + -- Warn about missing signatures, but not in interface mode + -- (This is important when renaming bindings from 'deriving' clauses.) + getModeRn `thenM` \ mode -> + doptM Opt_WarnMissingSigs `thenM` \ warn_missing_sigs -> + (if warn_missing_sigs && not (isInterfaceMode mode) then + let + type_sig_vars = [n | Sig n _ _ <- siglist] + un_sigd_binders = filter (not . (`elem` type_sig_vars)) + (nameSetToList binders) + in + mappM_ missingSigWarn un_sigd_binders + else + returnM () + ) `thenM_` -rnBinds EmptyBinds = returnRn (EmptyBinds,emptyUniqSet,[]) -rnBinds (SingleBind (RecBind bind)) = rnNestedMonoBinds bind [] -rnBinds (BindWith (RecBind bind) sigs) = rnNestedMonoBinds bind sigs - -- the parser doesn't produce other forms + returnM (final_binds, bind_fvs `plusFV` hsSigsFVs siglist) \end{code} -@rnNestedMonoBinds@ - - collects up the binders for this declaration group, - - checkes that they form a set - - extends the environment to bind them to new local names - - calls @rnMonoBinds@ to do the real work -In contrast, @rnTopMonoBinds@ doesn't extend the environment, because that's -already done in pass3. All it does is call @rnMonoBinds@ and discards -the free var info. +%************************************************************************ +%* * +%* Nested binds +%* * +%************************************************************************ \begin{code} -rnTopMonoBinds :: RdrNameMonoBinds -> [RdrNameSig] -> RnM_Fixes s RenamedHsBinds - -rnTopMonoBinds EmptyMonoBinds sigs = returnRn EmptyBinds - -rnTopMonoBinds mbs sigs - = rnBindSigs True{-top-level-} (collectMonoBinders mbs) sigs `thenRn` \ siglist -> - rnMonoBinds mbs siglist `thenRn` \ (new_binds, fv_set) -> - returnRn new_binds +rnMonoBindsAndThen :: RdrNameMonoBinds + -> [RdrNameSig] + -> (RenamedHsBinds -> RnM (result, FreeVars)) + -> RnM (result, FreeVars) + +rnMonoBindsAndThen mbinds sigs thing_inside -- Non-empty monobinds + = -- Extract all the binders in this group, and extend the + -- current scope, inventing new names for the new binders + -- This also checks that the names form a set + bindLocatedLocalsRn doc mbinders_w_srclocs $ \ new_mbinders -> + bindPatSigTyVars (collectSigTysFromMonoBinds mbinds) $ + -- Then install local fixity declarations + -- Notice that they scope over thing_inside too + bindLocalFixities [sig | FixSig sig <- sigs ] $ -rnNestedMonoBinds :: RdrNameMonoBinds -> [RdrNameSig] - -> RnM_Fixes s (RenamedHsBinds, FreeVars, [RnName]) + -- Do the business + rnMonoBinds mbinds sigs `thenM` \ (binds, bind_fvs) -> -rnNestedMonoBinds EmptyMonoBinds sigs - = returnRn (EmptyBinds, emptyUniqSet, []) + -- Now do the "thing inside" + thing_inside binds `thenM` \ (result,result_fvs) -> -rnNestedMonoBinds mbinds sigs -- Non-empty monobinds - = - -- Extract all the binders in this group, - -- and extend current scope, inventing new names for the new binders - -- This also checks that the names form a set + -- Final error checking let - mbinders_w_srclocs = collectMonoBindersAndLocs mbinds - mbinders = map fst mbinders_w_srclocs + all_fvs = result_fvs `plusFV` bind_fvs + unused_binders = filter (not . (`elemNameSet` all_fvs)) new_mbinders in - newLocalNames "variable" - mbinders_w_srclocs `thenRn` \ new_mbinders -> - - extendSS2 new_mbinders ( - rnBindSigs False{-not top- level-} mbinders sigs `thenRn` \ siglist -> - rnMonoBinds mbinds siglist - ) `thenRn` \ (new_binds, fv_set) -> - returnRn (new_binds, fv_set, new_mbinders) + warnUnusedLocalBinds unused_binders `thenM_` + + returnM (result, delListFromNameSet all_fvs new_mbinders) + where + mbinders_w_srclocs = collectLocatedMonoBinders mbinds + doc = text "In the binding group for:" + <+> pprWithCommas ppr (map fst mbinders_w_srclocs) \end{code} -@rnMonoBinds@ is used by *both* top-level and nested bindings. It -assumes that all variables bound in this group are already in scope. -This is done *either* by pass 3 (for the top-level bindings), -*or* by @rnNestedMonoBinds@ (for the nested ones). \begin{code} -rnMonoBinds :: RdrNameMonoBinds - -> [RenamedSig] -- Signatures attached to this group - -> RnM_Fixes s (RenamedHsBinds, FreeVars) +rnMonoBinds :: RdrNameMonoBinds + -> [RdrNameSig] + -> RnM (RenamedHsBinds, FreeVars) -rnMonoBinds mbinds siglist - = - -- Rename the bindings, returning a MonoBindsInfo - -- which is a list of indivisible vertices so far as - -- the strongly-connected-components (SCC) analysis is concerned - flattenMonoBinds 0 siglist mbinds `thenRn` \ (_, mbinds_info) -> +-- Assumes the binders of the binding are in scope already - -- Do the SCC analysis - let vertices = mkVertices mbinds_info - edges = mkEdges mbinds_info +rnMonoBinds mbinds sigs + = renameSigs sigs `thenM` \ siglist -> + rn_mono_binds siglist mbinds `thenM` \ (binders, final_binds, bind_fvs) -> + checkSigs okBindSig binders siglist `thenM_` + returnM (final_binds, bind_fvs `plusFV` hsSigsFVs siglist) +\end{code} - scc_result = stronglyConnComp (==) edges vertices +%************************************************************************ +%* * +\subsubsection{ MonoBinds -- the main work is done here} +%* * +%************************************************************************ - -- Deal with bound and free-var calculation - rhs_free_vars = foldr f emptyUniqSet mbinds_info +@rn_mono_binds@ is used by {\em both} top-level and nested bindings. +It assumes that all variables bound in this group are already in scope. +This is done {\em either} by pass 3 (for the top-level bindings), +{\em or} by @rnMonoBinds@ (for the nested ones). - final_binds = reconstructRec scc_result edges mbinds_info +\begin{code} +rn_mono_binds :: [RenamedSig] -- Signatures attached to this group + -> RdrNameMonoBinds + -> RnM (NameSet, -- Binders + RenamedHsBinds, -- Dependency analysed + FreeVars) -- Free variables + +rn_mono_binds siglist mbinds + = -- Rename the bindings, returning a MonoBindsInfo + -- which is a list of indivisible vertices so far as + -- the strongly-connected-components (SCC) analysis is concerned + flattenMonoBinds siglist mbinds `thenM` \ mbinds_info -> - happy_answer = returnRn (final_binds, rhs_free_vars) + -- Do the SCC analysis + let + scc_result = rnSCC mbinds_info + (binds_s, rhs_fvs_s) = unzip (map reconstructCycle scc_result) + final_binds = foldr ThenBinds EmptyBinds binds_s + + -- Deal with bound and free-var calculation + -- Caller removes binders from free-var set + rhs_fvs = plusFVs rhs_fvs_s + bndrs = plusFVs [defs | (defs,_,_,_) <- mbinds_info] in - case (inline_sigs_in_recursive_binds final_binds) of - Nothing -> happy_answer - Just names_n_locns -> --- SLPJ: sometimes want recursive INLINE for worker wrapper style stuff --- addErrRn (inlineInRecursiveBindsErr names_n_locns) `thenRn_` - {-not so-}happy_answer - where - f :: (a,b, FreeVars, c,d) -> FreeVars -> FreeVars - - f (_, _, fvs_body, _, _) fvs_sofar = fvs_sofar `unionUniqSets` fvs_body - - inline_sigs_in_recursive_binds (BindWith (RecBind _) sigs) - = case [(n, locn) | (InlineSig n locn) <- sigs ] of - [] -> Nothing - sigh -> -#if OMIT_DEFORESTER - Just sigh -#else - -- Allow INLINEd recursive functions if they are - -- designated DEFORESTable too. - case [(n, locn) | (DeforestSig n locn) <- sigs ] of - [] -> Just sigh - sigh -> Nothing -#endif - - inline_sigs_in_recursive_binds (ThenBinds b1 b2) - = case (inline_sigs_in_recursive_binds b1) of - Nothing -> inline_sigs_in_recursive_binds b2 - Just x -> Just x -- NB: won't report error(s) in b2 - - inline_sigs_in_recursive_binds anything_else = Nothing + returnM (bndrs, final_binds, rhs_fvs) \end{code} @flattenMonoBinds@ is ever-so-slightly magical in that it sticks unique ``vertex tags'' on its output; minor plumbing required. +Sigh --- need to pass along the signatures for the group of bindings, +in case any of them \fbox{\ ???\ } + \begin{code} -flattenMonoBinds :: Int -- Next free vertex tag - -> [RenamedSig] -- Signatures +flattenMonoBinds :: [RenamedSig] -- Signatures -> RdrNameMonoBinds - -> RnM_Fixes s (Int, FlatMonoBindsInfo) + -> RnM [FlatMonoBinds] -flattenMonoBinds uniq sigs EmptyMonoBinds = returnRn (uniq, []) +flattenMonoBinds sigs EmptyMonoBinds = returnM [] -flattenMonoBinds uniq sigs (AndMonoBinds bs1 bs2) - = flattenMonoBinds uniq sigs bs1 `thenRn` \ (uniq1, flat1) -> - flattenMonoBinds uniq1 sigs bs2 `thenRn` \ (uniq2, flat2) -> - returnRn (uniq2, flat1 ++ flat2) +flattenMonoBinds sigs (AndMonoBinds bs1 bs2) + = flattenMonoBinds sigs bs1 `thenM` \ flat1 -> + flattenMonoBinds sigs bs2 `thenM` \ flat2 -> + returnM (flat1 ++ flat2) -flattenMonoBinds uniq sigs (PatMonoBind pat grhss_and_binds locn) - = pushSrcLocRn locn $ - rnPat pat `thenRn` \ pat' -> - rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) -> +flattenMonoBinds sigs (PatMonoBind pat grhss locn) + = addSrcLoc locn $ + rnPat pat `thenM` \ (pat', pat_fvs) -> -- Find which things are bound in this group let - names_bound_here = collectPatBinders pat' - - sigs_etc_for_here = foldl (sig_for_here (\ n -> n `is_elem` names_bound_here)) - [] sigs - - sigs_fvs = foldr sig_fv emptyUniqSet sigs_etc_for_here - - is_elem = isIn "flattenMonoBinds" + names_bound_here = mkNameSet (collectPatBinders pat') in - returnRn ( - uniq + 1, - [(uniq, - mkUniqSet names_bound_here, - fvs `unionUniqSets` sigs_fvs, - PatMonoBind pat' grhss_and_binds' locn, - sigs_etc_for_here - )] - ) - -flattenMonoBinds uniq sigs (FunMonoBind name inf matches locn) - = pushSrcLocRn locn $ - lookupValue name `thenRn` \ name' -> - mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, fv_lists) -> - mapRn (checkPrecMatch inf name') new_matches `thenRn_` + sigsForMe names_bound_here sigs `thenM` \ sigs_for_me -> + rnGRHSs PatBindRhs grhss `thenM` \ (grhss', fvs) -> + returnM + [(names_bound_here, fvs `plusFV` pat_fvs, + PatMonoBind pat' grhss' locn, sigs_for_me + )] + +flattenMonoBinds sigs (FunMonoBind name inf matches locn) + = addSrcLoc locn $ + lookupBndrRn name `thenM` \ new_name -> let - fvs = unionManyUniqSets fv_lists + names_bound_here = unitNameSet new_name + in + sigsForMe names_bound_here sigs `thenM` \ sigs_for_me -> + mapFvRn (rnMatch (FunRhs new_name)) matches `thenM` \ (new_matches, fvs) -> + mappM_ (checkPrecMatch inf new_name) new_matches `thenM_` + returnM + [(unitNameSet new_name, fvs, + FunMonoBind new_name inf new_matches locn, sigs_for_me + )] - sigs_for_me = foldl (sig_for_here (\ n -> n == name')) [] sigs - sigs_fvs = foldr sig_fv emptyUniqSet sigs_for_me - in - returnRn ( - uniq + 1, - [(uniq, - unitUniqSet name', - fvs `unionUniqSets` sigs_fvs, - FunMonoBind name' inf new_matches locn, - sigs_for_me - )] - ) +sigsForMe names_bound_here sigs + = foldlM check [] (filter (sigForThisGroup names_bound_here) sigs) + where + check sigs sig = case filter (eqHsSig sig) sigs of + [] -> returnM (sig:sigs) + other -> dupSigDeclErr sig `thenM_` + returnM sigs \end{code} -Grab type-signatures/user-pragmas of interest: -\begin{code} -sig_for_here want_me acc s@(Sig n _ _ _) | want_me n = s:acc -sig_for_here want_me acc s@(InlineSig n _) | want_me n = s:acc -sig_for_here want_me acc s@(DeforestSig n _) | want_me n = s:acc -sig_for_here want_me acc s@(SpecSig n _ _ _) | want_me n = s:acc -sig_for_here want_me acc s@(MagicUnfoldingSig n _ _) - | want_me n = s:acc -sig_for_here want_me acc other_wise = acc - --- If a SPECIALIZE pragma is of the "... = blah" form, --- then we'd better make sure "blah" is taken into --- acct in the dependency analysis (or we get an --- unexpected out-of-scope error)! WDP 95/07 - -sig_fv (SpecSig _ _ (Just blah) _) acc = acc `unionUniqSets` unitUniqSet blah -sig_fv _ acc = acc -\end{code} -%************************************************************************ -%* * -\subsection[reconstruct-deps]{Reconstructing dependencies} -%* * -%************************************************************************ +@rnMethodBinds@ is used for the method bindings of a class and an instance +declaration. Like @rnMonoBinds@ but without dependency analysis. -This @MonoBinds@- and @ClassDecls@-specific code is segregated here, -as the two cases are similar. +NOTA BENE: we record each {\em binder} of a method-bind group as a free variable. +That's crucial when dealing with an instance decl: +\begin{verbatim} + instance Foo (T a) where + op x = ... +\end{verbatim} +This might be the {\em sole} occurrence of @op@ for an imported class @Foo@, +and unless @op@ occurs we won't treat the type signature of @op@ in the class +decl for @Foo@ as a source of instance-decl gates. But we should! Indeed, +in many ways the @op@ in an instance decl is just like an occurrence, not +a binder. \begin{code} -reconstructRec :: [Cycle] -- Result of SCC analysis; at least one - -> [Edge] -- Original edges - -> FlatMonoBindsInfo - -> RenamedHsBinds +rnMethodBinds :: Name -- Class name + -> [Name] -- Names for generic type variables + -> RdrNameMonoBinds + -> RnM (RenamedMonoBinds, FreeVars) -reconstructRec cycles edges mbi - = foldr1 ThenBinds (map (reconstructCycle mbi) cycles) - where - reconstructCycle :: FlatMonoBindsInfo -> Cycle -> RenamedHsBinds +rnMethodBinds cls gen_tyvars EmptyMonoBinds = returnM (EmptyMonoBinds, emptyFVs) - reconstructCycle mbi2 cycle - = case [(binds,sigs) | (vertex, _, _, binds, sigs) <- mbi2, vertex `is_elem` cycle] - of { relevant_binds_and_sigs -> +rnMethodBinds cls gen_tyvars (AndMonoBinds mb1 mb2) + = rnMethodBinds cls gen_tyvars mb1 `thenM` \ (mb1', fvs1) -> + rnMethodBinds cls gen_tyvars mb2 `thenM` \ (mb2', fvs2) -> + returnM (mb1' `AndMonoBinds` mb2', fvs1 `plusFV` fvs2) - case (unzip relevant_binds_and_sigs) of { (binds, sig_lists) -> +rnMethodBinds cls gen_tyvars (FunMonoBind name inf matches locn) + = addSrcLoc locn $ - case (foldr AndMonoBinds EmptyMonoBinds binds) of { this_gp_binds -> - let - this_gp_sigs = foldr1 (++) sig_lists - have_sigs = not (null sig_lists) - -- ToDo: this might not be the right - -- thing to call this predicate; - -- e.g. "have_sigs [[], [], []]" ??????????? - in - mk_binds this_gp_binds this_gp_sigs (isCyclic edges cycle) have_sigs - }}} - where - is_elem = isIn "reconstructRec" - - mk_binds :: RenamedMonoBinds -> [RenamedSig] - -> Bool -> Bool -> RenamedHsBinds - - mk_binds bs ss True False = SingleBind (RecBind bs) - mk_binds bs ss True True{-have sigs-} = BindWith (RecBind bs) ss - mk_binds bs ss False False = SingleBind (NonRecBind bs) - mk_binds bs ss False True{-have sigs-} = BindWith (NonRecBind bs) ss - - -- moved from Digraph, as this is the only use here - -- (avoid overloading cost). We have to use elem - -- (not FiniteMaps or whatever), because there may be - -- many edges out of one vertex. We give it its own - -- "elem" just for speed. - - isCyclic es [] = panic "isCyclic: empty component" - isCyclic es [v] = (v,v) `elem` es - isCyclic es vs = True - - elem _ [] = False - elem x (y:ys) = x==y || elem x ys + lookupInstDeclBndr cls name `thenM` \ sel_name -> + -- We use the selector name as the binder + + mapFvRn (rn_match sel_name) matches `thenM` \ (new_matches, fvs) -> + mappM_ (checkPrecMatch inf sel_name) new_matches `thenM_` + returnM (FunMonoBind sel_name inf new_matches locn, fvs `addOneFV` sel_name) + where + -- Gruesome; bring into scope the correct members of the generic type variables + -- See comments in RnSource.rnSourceDecl(ClassDecl) + rn_match sel_name match@(Match (TypePat ty : _) _ _) + = extendTyVarEnvFVRn gen_tvs $ + rnMatch (FunRhs sel_name) match + where + tvs = map rdrNameOcc (extractHsTyRdrNames ty) + gen_tvs = [tv | tv <- gen_tyvars, nameOccName tv `elem` tvs] + + rn_match sel_name match = rnMatch (FunRhs sel_name) match + + +-- Can't handle method pattern-bindings which bind multiple methods. +rnMethodBinds cls gen_tyvars mbind@(PatMonoBind other_pat _ locn) + = addSrcLoc locn (addErr (methodBindErr mbind)) `thenM_` + returnM (EmptyMonoBinds, emptyFVs) \end{code} + %************************************************************************ %* * -%* Manipulating FlatMonoBindInfo * + Strongly connected components + %* * %************************************************************************ -During analysis a @MonoBinds@ is flattened to a @FlatMonoBindsInfo@. +During analysis a @MonoBinds@ is flattened to a @FlatMonoBinds@. The @RenamedMonoBinds@ is always an empty bind, a pattern binding or a function binding, and has itself been dependency-analysed and renamed. \begin{code} -type FlatMonoBindsInfo - = [(VertexTag, -- Identifies the vertex - UniqSet RnName, -- Set of names defined in this vertex - UniqSet RnName, -- Set of names used in this vertex - RenamedMonoBinds, -- Binding for this vertex (always just one binding, either fun or pat) - [RenamedSig]) -- Signatures, if any, for this vertex - ] -mkVertices :: FlatMonoBindsInfo -> [VertexTag] -mkEdges :: FlatMonoBindsInfo -> [Edge] +type Defs = NameSet +type Uses = NameSet +type FlatMonoBinds = (Defs, Uses, RenamedMonoBinds, [RenamedSig]) + -- Signatures, if any, for this vertex + +rnSCC :: [FlatMonoBinds] -> [SCC FlatMonoBinds] +rnSCC nodes = stronglyConnComp (mkEdges nodes) -mkVertices info = [ vertex | (vertex,_,_,_,_) <- info] +type VertexTag = Int -mkEdges flat_info - -- An edge (v,v') indicates that v depends on v' - = -- pprTrace "mkEdges:" (ppAboves [ppAboves[ppInt v, ppCat [ppr PprDebug d|d <- uniqSetToList defd], ppCat [ppr PprDebug u|u <- uniqSetToList used]] | (v,defd,used,_,_) <- flat_info]) $ - [ (source_vertex, target_vertex) - | (source_vertex, _, used_names, _, _) <- flat_info, - target_name <- uniqSetToList used_names, - target_vertex <- vertices_defining target_name flat_info +mkEdges :: [FlatMonoBinds] -> [(FlatMonoBinds, VertexTag, [VertexTag])] + -- We keep the uses with the binding, + -- so we can track unused bindings better +mkEdges nodes + = [ (thing, tag, dest_vertices uses) + | (thing@(_, uses, _, _), tag) <- tagged_nodes ] - where - -- If each name only has one binding in this group, then - -- vertices_defining will always return the empty list, or a - -- singleton. The case when there is more than one binding (an - -- error) needs more thought. - - vertices_defining name flat_info2 - = [ vertex | (vertex, names_defined, _, _, _) <- flat_info2, - name `elementOfUniqSet` names_defined - ] + where + tagged_nodes = nodes `zip` [0::VertexTag ..] + + -- An edge (v,v') indicates that v depends on v' + dest_vertices uses = [ target_vertex + | ((defs, _, _, _), target_vertex) <- tagged_nodes, + defs `intersectsNameSet` uses + ] + +reconstructCycle :: SCC FlatMonoBinds -> (RenamedHsBinds, Uses) +reconstructCycle (AcyclicSCC (defs, uses, binds, sigs)) + = (MonoBind binds sigs NonRecursive, uses) +reconstructCycle (CyclicSCC cycle) + = (MonoBind this_gp_binds this_gp_sigs Recursive, + unionManyNameSets uses_s `minusNameSet` unionManyNameSets defs_s) + -- The uses of the cycle are the things used in any RHS + -- minus the binders of the group. Knocking them out + -- right here improves the error reporting for usused + -- bindings; e.g. f x = f x -- Otherwise unused + where + (defs_s, uses_s, binds_s, sigs_s) = unzip4 cycle + this_gp_binds = foldr1 AndMonoBinds binds_s + this_gp_sigs = foldr1 (++) sigs_s \end{code} @@ -503,147 +456,68 @@ mkEdges flat_info %* * %************************************************************************ -@rnBindSigs@ checks for: (a)~more than one sig for one thing; -(b)~signatures given for things not bound here; (c)~with suitably -flaggery, that all top-level things have type signatures. +@renameSigs@ checks for: +\begin{enumerate} +\item more than one sig for one thing; +\item signatures given for things not bound here; +\item with suitably flaggery, that all top-level things have type signatures. +\end{enumerate} +% +At the moment we don't gather free-var info from the types in +signatures. We'd only need this if we wanted to report unused tyvars. \begin{code} -rnBindSigs :: Bool -- True <=> top-level binders - -> [RdrName] -- Binders for this decl group - -> [RdrNameSig] - -> RnM_Fixes s [RenamedSig] -- List of Sig constructors - -rnBindSigs is_toplev binder_occnames sigs - = - -- Rename the signatures - -- Will complain about sigs for variables not in this group - mapRn rename_sig sigs `thenRn` \ sigs_maybe -> - let - sigs' = catMaybes sigs_maybe - - -- Discard unbound ones we've already complained about, so we - -- complain about duplicate ones. - - (goodies, dups) = removeDups compare (filter (\ x -> not_unbound x && not_main x) sigs') - in - mapRn (addErrRn . dupSigDeclErr) dups `thenRn_` - - getSrcLocRn `thenRn` \ locn -> - - (if (is_toplev && opt_SigsRequired) then - let - sig_frees = catMaybes (map (sig_free sigs) binder_occnames) - in - mapRn (addErrRn . missingSigErr locn) sig_frees - else - returnRn [] - ) `thenRn_` - - returnRn sigs' -- bad ones and all: - -- we need bindings of *some* sort for every name +checkSigs :: (NameSet -> RenamedSig -> Bool) -- OK-sig predicbate + -> NameSet -- Binders of this group + -> [RenamedSig] + -> RnM () +checkSigs ok_sig bndrs sigs + -- Check for (a) duplicate signatures + -- (b) signatures for things not in this group + -- Well, I can't see the check for (b)... ToDo! + = mappM_ unknownSigErr bad_sigs where - rename_sig (Sig v ty pragmas src_loc) - = pushSrcLocRn src_loc $ - if not (v `elem` binder_occnames) then - addErrRn (unknownSigDeclErr "type signature" v src_loc) `thenRn_` - returnRn Nothing - else - lookupValue v `thenRn` \ new_v -> - rnPolyType nullTyVarNamesEnv ty `thenRn` \ new_ty -> - - ASSERT(isNoGenPragmas pragmas) - returnRn (Just (Sig new_v new_ty noGenPragmas src_loc)) - - -- and now, the various flavours of value-modifying user-pragmas: - - rename_sig (SpecSig v ty using src_loc) - = pushSrcLocRn src_loc $ - if not (v `elem` binder_occnames) then - addErrRn (unknownSigDeclErr "SPECIALIZE pragma" v src_loc) `thenRn_` - returnRn Nothing - else - lookupValue v `thenRn` \ new_v -> - rnPolyType nullTyVarNamesEnv ty `thenRn` \ new_ty -> - rn_using using `thenRn` \ new_using -> - returnRn (Just (SpecSig new_v new_ty new_using src_loc)) - where - rn_using Nothing = returnRn Nothing - rn_using (Just x) = lookupValue x `thenRn` \ new_x -> - returnRn (Just new_x) - - rename_sig (InlineSig v src_loc) - = pushSrcLocRn src_loc $ - if not (v `elem` binder_occnames) then - addErrRn (unknownSigDeclErr "INLINE pragma" v src_loc) `thenRn_` - returnRn Nothing - else - lookupValue v `thenRn` \ new_v -> - returnRn (Just (InlineSig new_v src_loc)) - - rename_sig (DeforestSig v src_loc) - = pushSrcLocRn src_loc $ - if not (v `elem` binder_occnames) then - addErrRn (unknownSigDeclErr "DEFOREST pragma" v src_loc) `thenRn_` - returnRn Nothing - else - lookupValue v `thenRn` \ new_v -> - returnRn (Just (DeforestSig new_v src_loc)) - - rename_sig (MagicUnfoldingSig v str src_loc) - = pushSrcLocRn src_loc $ - if not (v `elem` binder_occnames) then - addErrRn (unknownSigDeclErr "MAGIC_UNFOLDING pragma" v src_loc) `thenRn_` - returnRn Nothing - else - lookupValue v `thenRn` \ new_v -> - returnRn (Just (MagicUnfoldingSig new_v str src_loc)) - - not_unbound, not_main :: RenamedSig -> Bool - - not_unbound (Sig n _ _ _) = not (isRnUnbound n) - not_unbound (SpecSig n _ _ _) = not (isRnUnbound n) - not_unbound (InlineSig n _) = not (isRnUnbound n) - not_unbound (DeforestSig n _) = not (isRnUnbound n) - not_unbound (MagicUnfoldingSig n _ _) = not (isRnUnbound n) - - not_main (Sig n _ _ _) = let str = getLocalName n in - not (str == SLIT("main") || str == SLIT("mainPrimIO")) - not_main _ = True - - ------------------------------------- - sig_free :: [RdrNameSig] -> RdrName -> Maybe RdrName - -- Return "Just x" if "x" has no type signature in - -- sigs. Nothing, otherwise. - - sig_free [] ny = Just ny - sig_free (Sig nx _ _ _ : rest) ny - = if (nx == ny) then Nothing else sig_free rest ny - sig_free (_ : rest) ny = sig_free rest ny - - ------------------------------------- - compare :: RenamedSig -> RenamedSig -> TAG_ - compare (Sig n1 _ _ _) (Sig n2 _ _ _) = n1 `cmp` n2 - compare (InlineSig n1 _) (InlineSig n2 _) = n1 `cmp` n2 - compare (MagicUnfoldingSig n1 _ _) (MagicUnfoldingSig n2 _ _) = n1 `cmp` n2 - compare (SpecSig n1 ty1 _ _) (SpecSig n2 ty2 _ _) - = -- may have many specialisations for one value; - -- but not ones that are exactly the same... - thenCmp (n1 `cmp` n2) (cmpPolyType cmp ty1 ty2) - - compare other_1 other_2 -- tags *must* be different - = let tag1 = tag other_1 - tag2 = tag other_2 - in - if tag1 _LT_ tag2 then LT_ else GT_ - - tag (Sig n1 _ _ _) = (ILIT(1) :: FAST_INT) - tag (SpecSig n1 _ _ _) = ILIT(2) - tag (InlineSig n1 _) = ILIT(3) - tag (MagicUnfoldingSig n1 _ _) = ILIT(4) - tag (DeforestSig n1 _) = ILIT(5) - tag _ = panic# "tag(RnBinds)" + bad_sigs = filter (not . ok_sig bndrs) sigs + +-- We use lookupSigOccRn in the signatures, which is a little bit unsatisfactory +-- because this won't work for: +-- instance Foo T where +-- {-# INLINE op #-} +-- Baz.op = ... +-- We'll just rename the INLINE prag to refer to whatever other 'op' +-- is in scope. (I'm assuming that Baz.op isn't in scope unqualified.) +-- Doesn't seem worth much trouble to sort this. + +renameSigs :: [Sig RdrName] -> RnM [Sig Name] +renameSigs sigs = mappM renameSig (filter (not . isFixitySig) sigs) + -- Remove fixity sigs which have been dealt with already + +renameSig :: Sig RdrName -> RnM (Sig Name) +-- ClassOpSig, FixitSig is renamed elsewhere. +renameSig (Sig v ty src_loc) + = addSrcLoc src_loc $ + lookupSigOccRn v `thenM` \ new_v -> + rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> + returnM (Sig new_v new_ty src_loc) + +renameSig (SpecInstSig ty src_loc) + = addSrcLoc src_loc $ + rnHsType (text "A SPECIALISE instance pragma") ty `thenM` \ new_ty -> + returnM (SpecInstSig new_ty src_loc) + +renameSig (SpecSig v ty src_loc) + = addSrcLoc src_loc $ + lookupSigOccRn v `thenM` \ new_v -> + rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> + returnM (SpecSig new_v new_ty src_loc) + +renameSig (InlineSig b v p src_loc) + = addSrcLoc src_loc $ + lookupSigOccRn v `thenM` \ new_v -> + returnM (InlineSig b new_v p src_loc) \end{code} + %************************************************************************ %* * \subsection{Error messages} @@ -651,46 +525,25 @@ rnBindSigs is_toplev binder_occnames sigs %************************************************************************ \begin{code} -dupSigDeclErr sigs - = let - undup_sigs = fst (removeDups cmp_sig sigs) - in - addErrLoc locn1 - ("more than one "++what_it_is++"\n\thas been given for these variables") ( \ sty -> - ppAboves (map (ppr sty) undup_sigs) ) +dupSigDeclErr sig + = addSrcLoc loc $ + addErr (sep [ptext SLIT("Duplicate") <+> what_it_is <> colon, + ppr sig]) + where + (what_it_is, loc) = hsSigDoc sig + +unknownSigErr sig + = addSrcLoc loc $ + addErr (sep [ptext SLIT("Misplaced") <+> what_it_is <> colon, + ppr sig]) where - (what_it_is, locn1) - = case (head sigs) of - Sig _ _ _ loc -> ("type signature",loc) - ClassOpSig _ _ _ loc -> ("class-method type signature", loc) - SpecSig _ _ _ loc -> ("SPECIALIZE pragma",loc) - InlineSig _ loc -> ("INLINE pragma",loc) - MagicUnfoldingSig _ _ loc -> ("MAGIC_UNFOLDING pragma",loc) - - cmp_sig a b = get_name a `cmp` get_name b - - get_name (Sig n _ _ _) = n - get_name (ClassOpSig n _ _ _) = n - get_name (SpecSig n _ _ _) = n - get_name (InlineSig n _) = n - get_name (MagicUnfoldingSig n _ _) = n - ------------------------- -methodBindErr mbind locn - = addErrLoc locn "Can't handle multiple methods defined by one pattern binding" - (\ sty -> ppr sty mbind) - --------------------------- -missingSigErr locn var - = addShortErrLocLine locn ( \ sty -> - ppBesides [ppStr "a definition but no type signature for `", - ppr sty var, - ppStr "'."]) - --------------------------------- -unknownSigDeclErr flavor var locn - = addShortErrLocLine locn ( \ sty -> - ppBesides [ppStr flavor, ppStr " but no definition for `", - ppr sty var, - ppStr "'."]) + (what_it_is, loc) = hsSigDoc sig + +missingSigWarn var + = addSrcLoc (nameSrcLoc var) $ + addWarn (sep [ptext SLIT("Definition but no type signature for"), quotes (ppr var)]) + +methodBindErr mbind + = hang (ptext SLIT("Can't handle multiple methods defined by one pattern binding")) + 4 (ppr mbind) \end{code}