X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnBinds.lhs;h=9f7e690707cea9a1efcb5f78e2bbc52adaed998d;hb=8fc898cb0b722e72c08dce3acadbc4b2aa2249ff;hp=07e4fa12072152450e745167bbf00d9b790b5647;hpb=7e602b0a11e567fcb035d1afd34015aebcf9a577;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnBinds.lhs b/ghc/compiler/rename/RnBinds.lhs index 07e4fa1..9f7e690 100644 --- a/ghc/compiler/rename/RnBinds.lhs +++ b/ghc/compiler/rename/RnBinds.lhs @@ -10,33 +10,33 @@ they may be affected by renaming (which isn't fully worked out yet). \begin{code} module RnBinds ( - rnTopBinds, rnTopMonoBinds, - rnMethodBinds, renameSigs, - rnBinds, rnMonoBinds + rnTopMonoBinds, rnMonoBinds, rnMonoBindsAndThen, + rnMethodBinds, renameSigs, checkSigs, unknownSigErr ) where #include "HsVersions.h" -import {-# SOURCE #-} RnSource ( rnHsSigType ) import HsSyn -import HsBinds ( sigsForMe ) +import HsBinds ( hsSigDoc, sigLoc, eqHsSig ) import RdrHsSyn import RnHsSyn -import RnMonad -import RnExpr ( rnMatch, rnGRHSs, rnPat, checkPrecMatch ) -import RnEnv ( bindLocatedLocalsRn, lookupBndrRn, lookupOccRn, lookupGlobalOccRn, - isUnboundName, warnUnusedBinds, - FreeVars, emptyFVs, plusFV, plusFVs, unitFV +import TcRnMonad +import RnTypes ( rnHsSigType, rnHsType, rnPat ) +import RnExpr ( rnMatch, rnGRHSs, checkPrecMatch ) +import RnEnv ( bindLocatedLocalsRn, lookupBndrRn, lookupInstDeclBndr, + lookupSigOccRn, bindPatSigTyVars, bindPatSigTyVarsFV, + bindLocalFixities, + warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn, ) -import CmdLineOpts ( opt_WarnMissingSigs ) -import Digraph ( stronglyConnComp, SCC(..) ) -import Name ( OccName, Name ) +import CmdLineOpts ( DynFlag(..) ) +import Digraph ( SCC(..), stronglyConnComp ) +import Name ( Name, nameOccName, nameSrcLoc ) import NameSet -import BasicTypes ( RecFlag(..), TopLevelFlag(..) ) -import Util ( thenCmp, removeDups ) -import ListSetOps ( minusList ) -import Bag ( bagToList ) +import PrelNames ( isUnboundName ) +import RdrName ( RdrName, rdrNameOcc ) +import BasicTypes ( RecFlag(..), TopLevelFlag(..), isTopLevel ) +import List ( unzip4 ) import Outputable \end{code} @@ -66,11 +66,6 @@ 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} %************************************************************************ %* * @@ -113,7 +108,7 @@ 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 @@ -147,122 +142,138 @@ it expects the global environment to contain bindings for the binders %************************************************************************ %* * -%* Top-level bindings +\subsubsection{ Top-level bindings} %* * %************************************************************************ -@rnTopBinds@ assumes that the environment already +@rnTopMonoBinds@ assumes that the environment already contains bindings for the binders of this particular binding. \begin{code} -rnTopBinds :: RdrNameHsBinds -> RnMS s (RenamedHsBinds, FreeVars) - -rnTopBinds EmptyBinds = returnRn (EmptyBinds, emptyFVs) -rnTopBinds (MonoBind bind sigs _) = rnTopMonoBinds bind sigs - -- The parser doesn't produce other forms - +rnTopMonoBinds :: RdrNameMonoBinds + -> [RdrNameSig] + -> RnM (RenamedHsBinds, DefUses) -rnTopMonoBinds EmptyMonoBinds sigs - = returnRn (EmptyBinds, emptyFVs) +-- The binders of the binding are in scope already; +-- the top level scope resolution does that rnTopMonoBinds mbinds sigs - = mapRn lookupBndrRn binder_rdr_names `thenRn` \ binder_names -> - let - binder_set = mkNameSet binder_names - in - rn_mono_binds TopLevel binder_set mbinds sigs - where - binder_rdr_names = map fst (bagToList (collectMonoBinders mbinds)) + = bindPatSigTyVars (collectSigTysFromMonoBinds mbinds) $ \ _ -> + -- Hmm; by analogy with Ids, this doesn't look right + -- Top-level bound type vars should really scope over + -- everything, but we only scope them over the other bindings + + rnMonoBinds TopLevel mbinds sigs \end{code} + %************************************************************************ %* * %* Nested binds %* * %************************************************************************ -@rnMonoBinds@ - - collects up the binders for this declaration group, - - checks that they form a set - - extends the environment to bind them to new local names - - calls @rnMonoBinds@ to do the real work - \begin{code} -rnBinds :: RdrNameHsBinds - -> (RenamedHsBinds -> RnMS s (result, FreeVars)) - -> RnMS s (result, FreeVars) - -rnBinds EmptyBinds thing_inside = thing_inside EmptyBinds -rnBinds (MonoBind bind sigs _) thing_inside = rnMonoBinds bind sigs thing_inside - -- the parser doesn't produce other forms +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 $ \ _ -> + bindPatSigTyVarsFV (collectSigTysFromMonoBinds mbinds) $ + -- Then install local fixity declarations + -- Notice that they scope over thing_inside too + bindLocalFixities [sig | FixSig sig <- sigs ] $ -rnMonoBinds :: RdrNameMonoBinds -> [RdrNameSig] - -> (RenamedHsBinds -> RnMS s (result, FreeVars)) - -> RnMS s (result, FreeVars) + -- Do the business + rnMonoBinds NotTopLevel mbinds sigs `thenM` \ (binds, bind_dus) -> -rnMonoBinds EmptyMonoBinds sigs thing_inside = thing_inside EmptyBinds + -- Now do the "thing inside" + thing_inside binds `thenM` \ (result,result_fvs) -> -rnMonoBinds mbinds sigs thing_inside -- 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 - bindLocatedLocalsRn (text "binding group") mbinders_w_srclocs $ \ new_mbinders -> + -- Final error checking let - binder_set = mkNameSet new_mbinders + all_uses = duUses bind_dus `plusFV` result_fvs + bndrs = duDefs bind_dus + unused_bndrs = nameSetToList (bndrs `minusNameSet` all_uses) in - rn_mono_binds NotTopLevel - binder_set mbinds sigs `thenRn` \ (binds,bind_fvs) -> - - -- Now do the "thing inside", and deal with the free-variable calculations - thing_inside binds `thenRn` \ (result,result_fvs) -> - let - all_fvs = result_fvs `plusFV` bind_fvs - unused_binders = nameSetToList (binder_set `minusNameSet` all_fvs) - in - warnUnusedBinds unused_binders `thenRn_` - returnRn (result, delListFromNameSet all_fvs new_mbinders) + warnUnusedLocalBinds unused_bndrs `thenM_` + + returnM (result, all_uses `minusNameSet` bndrs) + -- duUses: It's important to return all the uses, not the 'real uses' used for + -- warning about unused bindings. Otherwise consider: + -- x = 3 + -- y = let p = x in 'x' -- NB: p not used + -- If we don't "see" the dependency of 'y' on 'x', we may put the + -- bindings in the wrong order, and the type checker will complain + -- that x isn't in scope where - mbinders_w_srclocs = bagToList (collectMonoBinders mbinds) + mbinders_w_srclocs = collectLocatedMonoBinders mbinds + doc = text "In the binding group for:" + <+> pprWithCommas ppr (map fst mbinders_w_srclocs) \end{code} %************************************************************************ %* * -%* MonoBinds -- the main work is done here +\subsubsection{ MonoBinds -- the main work is done here} %* * %************************************************************************ -@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). +@rnMonoBinds@ 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). \begin{code} -rn_mono_binds :: TopLevelFlag - -> NameSet -- Binders of this group - -> RdrNameMonoBinds - -> [RdrNameSig] -- Signatures attached to this group - -> RnMS s (RenamedHsBinds, -- - FreeVars) -- Free variables - -rn_mono_binds top_lev binders mbinds sigs - = - -- Rename the bindings, returning a MonoBindsInfo +rnMonoBinds :: TopLevelFlag + -> RdrNameMonoBinds + -> [RdrNameSig] + -> RnM (RenamedHsBinds, DefUses) + +-- Assumes the binders of the binding are in scope already + +rnMonoBinds top_lvl mbinds sigs + = renameSigs sigs `thenM` \ 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 - renameSigs top_lev False binders sigs `thenRn` \ siglist -> - flattenMonoBinds siglist mbinds `thenRn` \ mbinds_info -> + flattenMonoBinds siglist mbinds `thenM` \ mbinds_info -> -- Do the SCC analysis - let edges = mkEdges (mbinds_info `zip` [(0::Int)..]) - scc_result = stronglyConnComp edges - final_binds = foldr1 ThenBinds (map reconstructCycle scc_result) - - -- Deal with bound and free-var calculation - rhs_fvs = plusFVs [fvs | (_,fvs,_,_) <- mbinds_info] + let + scc_result = rnSCC mbinds_info + (binds_s, bind_dus_s) = unzip (map reconstructCycle scc_result) + bind_dus = mkDUs bind_dus_s + final_binds = foldr ThenBinds EmptyBinds binds_s + binders = duDefs bind_dus in - returnRn (final_binds, rhs_fvs) + -- Check for duplicate or mis-placed signatures + checkSigs (okBindSig binders) siglist `thenM_` + + -- Warn about missing signatures, + -- but only at top level, and not in interface mode + -- (The latter is important when renaming bindings from 'deriving' clauses.) + doptM Opt_WarnMissingSigs `thenM` \ warn_missing_sigs -> + (if isTopLevel top_lvl && + warn_missing_sigs + 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_` + + returnM (final_binds, bind_dus `plusDU` usesOnly (hsSigsFVs siglist)) \end{code} @flattenMonoBinds@ is ever-so-slightly magical in that it sticks @@ -271,154 +282,160 @@ unique ``vertex tags'' on its output; minor plumbing required. \begin{code} flattenMonoBinds :: [RenamedSig] -- Signatures -> RdrNameMonoBinds - -> RnMS s [FlatMonoBindsInfo] + -> RnM [FlatMonoBinds] -flattenMonoBinds sigs EmptyMonoBinds = returnRn [] +flattenMonoBinds sigs EmptyMonoBinds = returnM [] flattenMonoBinds sigs (AndMonoBinds bs1 bs2) - = flattenMonoBinds sigs bs1 `thenRn` \ flat1 -> - flattenMonoBinds sigs bs2 `thenRn` \ flat2 -> - returnRn (flat1 ++ flat2) + = flattenMonoBinds sigs bs1 `thenM` \ flat1 -> + flattenMonoBinds sigs bs2 `thenM` \ flat2 -> + returnM (flat1 ++ flat2) flattenMonoBinds sigs (PatMonoBind pat grhss locn) - = pushSrcLocRn locn $ - rnPat pat `thenRn` \ (pat', pat_fvs) -> + = addSrcLoc locn $ + rnPat pat `thenM` \ (pat', pat_fvs) -> -- Find which things are bound in this group let names_bound_here = mkNameSet (collectPatBinders pat') - sigs_for_me = sigsForMe (`elemNameSet` names_bound_here) sigs - sigs_fvs = foldr sig_fv emptyFVs sigs_for_me - fixity_sigs = [(name,sig) | FixSig sig@(FixitySig name _ _) <- sigs_for_me] in - extendFixityEnv fixity_sigs $ - rnGRHSs grhss `thenRn` \ (grhss', fvs) -> - returnRn - [(names_bound_here, - fvs `plusFV` sigs_fvs `plusFV` pat_fvs, - PatMonoBind pat' grhss' locn, - sigs_for_me - )] + 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) - = pushSrcLocRn locn $ - lookupBndrRn name `thenRn` \ name' -> + = addSrcLoc locn $ + lookupBndrRn name `thenM` \ new_name -> let - sigs_for_me = sigsForMe (name' ==) sigs - sigs_fvs = foldr sig_fv emptyFVs sigs_for_me - fixity_sigs = [(name,sig) | FixSig sig@(FixitySig name _ _) <- sigs_for_me] + names_bound_here = unitNameSet new_name in - extendFixityEnv fixity_sigs $ - mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, fv_lists) -> - mapRn (checkPrecMatch inf name') new_matches `thenRn_` - returnRn - [(unitNameSet name', - plusFVs fv_lists `plusFV` sigs_fvs, - FunMonoBind name' inf new_matches locn, - sigs_for_me - )] + 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 + )] + +sigsForMe names_bound_here sigs + = foldlM check [] (filter (sigForThisGroup names_bound_here) sigs) + where + -- sigForThisGroup only returns signatures for + -- which sigName returns a Just + check sigs sig = case filter (eqHsSig sig) sigs of + [] -> returnM (sig:sigs) + other -> dupSigDeclErr sig other `thenM_` + returnM sigs \end{code} -@rnMethodBinds@ is used for the method bindings of an instance -declaration. like @rnMonoBinds@ but without dependency analysis. +@rnMethodBinds@ is used for the method bindings of a class and an instance +declaration. Like @rnMonoBinds@ but without dependency analysis. + +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} -rnMethodBinds :: RdrNameMonoBinds -> RnMS s (RenamedMonoBinds, FreeVars) +rnMethodBinds :: Name -- Class name + -> [Name] -- Names for generic type variables + -> RdrNameMonoBinds + -> RnM (RenamedMonoBinds, FreeVars) -rnMethodBinds EmptyMonoBinds = returnRn (EmptyMonoBinds, emptyFVs) +rnMethodBinds cls gen_tyvars EmptyMonoBinds = returnM (EmptyMonoBinds, emptyFVs) -rnMethodBinds (AndMonoBinds mb1 mb2) - = rnMethodBinds mb1 `thenRn` \ (mb1', fvs1) -> - rnMethodBinds mb2 `thenRn` \ (mb2', fvs2) -> - returnRn (mb1' `AndMonoBinds` mb2', fvs1 `plusFV` fvs2) +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) -rnMethodBinds (FunMonoBind name inf matches locn) - = pushSrcLocRn locn $ +rnMethodBinds cls gen_tyvars (FunMonoBind name inf matches locn) + = addSrcLoc locn $ - lookupGlobalOccRn name `thenRn` \ sel_name -> + lookupInstDeclBndr cls name `thenM` \ sel_name -> -- We use the selector name as the binder - mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, fvs_s) -> - mapRn (checkPrecMatch inf sel_name) new_matches `thenRn_` - returnRn (FunMonoBind sel_name inf new_matches locn, plusFVs fvs_s) - -rnMethodBinds (PatMonoBind (VarPatIn name) grhss locn) - = pushSrcLocRn locn $ - lookupGlobalOccRn name `thenRn` \ sel_name -> - rnGRHSs grhss `thenRn` \ (grhss', fvs) -> - returnRn (PatMonoBind (VarPatIn sel_name) grhss' locn, fvs) + 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 (extractHsTyRdrTyVars 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 mbind@(PatMonoBind other_pat _ locn) - = pushSrcLocRn locn $ - failWithRn (EmptyMonoBinds, emptyFVs) (methodBindErr mbind) +rnMethodBinds cls gen_tyvars mbind@(PatMonoBind other_pat _ locn) + = addSrcLoc locn (addErr (methodBindErr mbind)) `thenM_` + returnM (EmptyMonoBinds, emptyFVs) \end{code} -\begin{code} --- 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 `plusFV` unitFV blah -sig_fv _ acc = acc -\end{code} %************************************************************************ %* * -\subsection[reconstruct-deps]{Reconstructing dependencies} -%* * -%************************************************************************ - -This @MonoBinds@- and @ClassDecls@-specific code is segregated here, -as the two cases are similar. - -\begin{code} -reconstructCycle :: SCC FlatMonoBindsInfo - -> RenamedHsBinds - -reconstructCycle (AcyclicSCC (_, _, binds, sigs)) - = MonoBind binds sigs NonRecursive - -reconstructCycle (CyclicSCC cycle) - = MonoBind this_gp_binds this_gp_sigs Recursive - where - this_gp_binds = foldr1 AndMonoBinds [binds | (_, _, binds, _) <- cycle] - this_gp_sigs = foldr1 (++) [sigs | (_, _, _, sigs) <- cycle] -\end{code} + Strongly connected components -%************************************************************************ -%* * -%* Manipulating FlatMonoBindInfo * %* * %************************************************************************ -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 - = (NameSet, -- Set of names defined in this vertex - NameSet, -- Set of names used in this vertex - RenamedMonoBinds, - [RenamedSig]) -- Signatures, if any, for this vertex +type FlatMonoBinds = (Defs, Uses, RenamedMonoBinds, [RenamedSig]) + -- Signatures, if any, for this vertex -mkEdges :: [(FlatMonoBindsInfo, VertexTag)] -> [(FlatMonoBindsInfo, VertexTag, [VertexTag])] +rnSCC :: [FlatMonoBinds] -> [SCC FlatMonoBinds] +rnSCC nodes = stronglyConnComp (mkEdges nodes) -mkEdges flat_info - = [ (info, tag, dest_vertices (nameSetToList names_used)) - | (info@(names_defined, names_used, mbind, sigs), tag) <- flat_info +type VertexTag = Int + +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 + tagged_nodes = nodes `zip` [0::VertexTag ..] + -- An edge (v,v') indicates that v depends on v' - dest_vertices src_mentions = [ target_vertex - | ((names_defined, _, _, _), target_vertex) <- flat_info, - mentioned_name <- src_mentions, - mentioned_name `elemNameSet` names_defined - ] + dest_vertices uses = [ target_vertex + | ((defs, _, _, _), target_vertex) <- tagged_nodes, + defs `intersectsNameSet` uses + ] + +reconstructCycle :: SCC FlatMonoBinds -> (RenamedHsBinds, (Defs,Uses)) +reconstructCycle (AcyclicSCC (defs, uses, binds, sigs)) + = (MonoBind binds sigs NonRecursive, (defs, uses)) +reconstructCycle (CyclicSCC cycle) + = (MonoBind this_gp_binds this_gp_sigs Recursive, + (unionManyNameSets defs_s, unionManyNameSets uses_s)) + 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} @@ -428,112 +445,69 @@ mkEdges flat_info %* * %************************************************************************ -@renameSigs@ 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 -sigatures. We'd only need this if we wanted to report unused tyvars. +signatures. We'd only need this if we wanted to report unused tyvars. \begin{code} -renameSigs :: TopLevelFlag - -> Bool -- True <-> sigs for an instance decl - -- hence SPECIALISE instance prags ok - -> NameSet -- Set of names bound in this group - -> [RdrNameSig] - -> RnMS s [RenamedSig] -- List of Sig constructors - -renameSigs top_lev inst_decl binders sigs - = -- Rename the signatures - mapRn renameSig sigs `thenRn` \ sigs' -> - +checkSigs :: (RenamedSig -> Bool) -- OK-sig predicbate + -> [RenamedSig] + -> RnM () +checkSigs ok_sig sigs -- Check for (a) duplicate signatures -- (b) signatures for things not in this group - -- (c) optionally, bindings with no signature - let - (goodies, dups) = removeDups cmp_sig (sigsForMe (not . isUnboundName) sigs') - not_this_group = sigsForMe (not . (`elemNameSet` binders)) goodies - spec_inst_sigs = [s | s@(SpecInstSig _ _) <- goodies] - type_sig_vars = [n | Sig n _ _ <- goodies] - sigs_required = case top_lev of {TopLevel -> opt_WarnMissingSigs; NotTopLevel -> False} - un_sigd_binders | sigs_required = nameSetToList binders `minusList` type_sig_vars - | otherwise = [] - in - mapRn dupSigDeclErr dups `thenRn_` - mapRn unknownSigErr not_this_group `thenRn_` - (if not inst_decl then - mapRn unknownSigErr spec_inst_sigs - else - returnRn [] - ) `thenRn_` - mapRn (addWarnRn.missingSigWarn) un_sigd_binders `thenRn_` - - returnRn sigs' -- bad ones and all: - -- we need bindings of *some* sort for every name - - + -- Well, I can't see the check for (a)... ToDo! + = mappM_ unknownSigErr (filter bad sigs) + where + bad sig = not (ok_sig sig) && + case sigName sig of + Just n | isUnboundName n -> False -- Don't complain about an unbound name again + other -> True + +-- 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) +-- FixitSig is renamed elsewhere. renameSig (Sig v ty src_loc) - = pushSrcLocRn src_loc $ - lookupBndrRn v `thenRn` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenRn` \ (new_ty,_) -> - returnRn (Sig new_v new_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) - = pushSrcLocRn src_loc $ - rnHsSigType (text "A SPECIALISE instance pragma") ty `thenRn` \ (new_ty, _) -> - returnRn (SpecInstSig new_ty src_loc) - -renameSig (SpecSig v ty using src_loc) - = pushSrcLocRn src_loc $ - lookupBndrRn v `thenRn` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenRn` \ (new_ty,_) -> - rn_using using `thenRn` \ new_using -> - returnRn (SpecSig new_v new_ty new_using src_loc) - where - rn_using Nothing = returnRn Nothing - rn_using (Just x) = lookupOccRn x `thenRn` \ new_x -> - returnRn (Just new_x) - -renameSig (InlineSig v src_loc) - = pushSrcLocRn src_loc $ - lookupBndrRn v `thenRn` \ new_v -> - returnRn (InlineSig new_v src_loc) - -renameSig (FixSig (FixitySig v fix src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn v `thenRn` \ new_v -> - returnRn (FixSig (FixitySig new_v fix src_loc)) - -renameSig (NoInlineSig v src_loc) - = pushSrcLocRn src_loc $ - lookupBndrRn v `thenRn` \ new_v -> - returnRn (NoInlineSig new_v 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} -Checking for distinct signatures; oh, so boring - -\begin{code} -cmp_sig :: RenamedSig -> RenamedSig -> Ordering -cmp_sig (Sig n1 _ _) (Sig n2 _ _) = n1 `compare` n2 -cmp_sig (InlineSig n1 _) (InlineSig n2 _) = n1 `compare` n2 -cmp_sig (NoInlineSig n1 _) (NoInlineSig n2 _) = n1 `compare` n2 -cmp_sig (SpecInstSig ty1 _) (SpecInstSig ty2 _) = cmpHsType compare ty1 ty2 -cmp_sig (SpecSig n1 ty1 _ _) (SpecSig n2 ty2 _ _) - = -- may have many specialisations for one value; - -- but not ones that are exactly the same... - thenCmp (n1 `compare` n2) (cmpHsType compare ty1 ty2) - -cmp_sig other_1 other_2 -- Tags *must* be different - | (sig_tag other_1) _LT_ (sig_tag other_2) = LT - | otherwise = GT - -sig_tag (Sig n1 _ _) = (ILIT(1) :: FAST_INT) -sig_tag (SpecSig n1 _ _ _) = ILIT(2) -sig_tag (InlineSig n1 _) = ILIT(3) -sig_tag (NoInlineSig n1 _) = ILIT(4) -sig_tag (SpecInstSig _ _) = ILIT(5) -sig_tag _ = panic# "tag(RnBinds)" -\end{code} %************************************************************************ %* * @@ -542,31 +516,24 @@ sig_tag _ = panic# "tag(RnBinds)" %************************************************************************ \begin{code} -dupSigDeclErr (sig:sigs) - = pushSrcLocRn loc $ - addErrRn (sep [ptext SLIT("Duplicate"), - ptext what_it_is <> colon, - ppr sig]) +dupSigDeclErr sig sigs + = addSrcLoc loc $ + addErr (vcat [ptext SLIT("Duplicate") <+> what_it_is <> colon, + nest 2 (vcat (map ppr_sig (sig:sigs)))]) where - (what_it_is, loc) = sig_doc sig + (what_it_is, loc) = hsSigDoc sig + ppr_sig sig = ppr (sigLoc sig) <> colon <+> ppr sig unknownSigErr sig - = pushSrcLocRn loc $ - addErrRn (sep [ptext SLIT("Misplaced"), - ptext what_it_is <> colon, + = addSrcLoc loc $ + addErr (sep [ptext SLIT("Misplaced") <+> what_it_is <> colon, ppr sig]) where - (what_it_is, loc) = sig_doc sig - -sig_doc (Sig _ _ loc) = (SLIT("type signature"),loc) -sig_doc (ClassOpSig _ _ _ loc) = (SLIT("class-method type signature"), loc) -sig_doc (SpecSig _ _ _ loc) = (SLIT("SPECIALISE pragma"),loc) -sig_doc (InlineSig _ loc) = (SLIT("INLINE pragma"),loc) -sig_doc (NoInlineSig _ loc) = (SLIT("NOINLINE pragma"),loc) -sig_doc (SpecInstSig _ loc) = (SLIT("SPECIALISE instance pragma"),loc) + (what_it_is, loc) = hsSigDoc sig missingSigWarn var - = sep [ptext SLIT("definition but no type signature for"), quotes (ppr 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"))