X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnBinds.lhs;h=628f67e9d91ce9456de01d39f3514d53f5eef358;hb=e8687b3cb725bcc7d6cd38aa9bd71b2ba5a763f1;hp=ecd3b3d04a239fffdbbe8466912c42760ffde370;hpb=9da4639011348fb6c318e3cba4b08622f811d9c4;p=ghc-hetmet.git diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs index ecd3b3d..628f67e 100644 --- a/compiler/rename/RnBinds.lhs +++ b/compiler/rename/RnBinds.lhs @@ -9,11 +9,18 @@ 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} -module RnBinds ( - rnTopBinds, - rnLocalBindsAndThen, rnValBindsAndThen, rnValBinds, trimWith, - rnMethodBinds, renameSigs, mkSigTvFn, - rnMatchGroup, rnGRHSs +{-# OPTIONS -w #-} +-- The above warning supression flag is a temporary kludge. +-- While working on this module you are encouraged to remove it and fix +-- any warnings in the module. See +-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings +-- for details + +module RnBinds (rnTopBinds, rnTopBindsLHS, rnTopBindsRHS, -- use these for top-level bindings + rnLocalBindsAndThen, rnValBindsLHS, rnValBindsRHS, -- or these for local bindings + rnMethodBinds, renameSigs, mkSigTvFn, + rnMatchGroup, rnGRHSs, + makeMiniFixityEnv ) where #include "HsVersions.h" @@ -24,21 +31,30 @@ import HsSyn import RdrHsSyn import RnHsSyn import TcRnMonad -import RnTypes ( rnHsSigType, rnLHsType, rnHsTypeFVs, - rnLPat, rnPatsAndThen, patSigErr, checkPrecMatch ) -import RnEnv ( bindLocatedLocalsRn, lookupLocatedBndrRn, - lookupLocatedInstDeclBndr, newIPNameRn, - lookupLocatedSigOccRn, bindPatSigTyVarsFV, - bindLocalFixities, bindSigTyVarsFV, - warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn, +import RnTypes ( rnHsSigType, rnLHsType, rnHsTypeFVs,checkPrecMatch) +import RnPat (rnPatsAndThen_LocalRightwards, rnBindPat, + NameMaker, localRecNameMaker, topRecNameMaker, applyNameMaker, + patSigErr) + +import RnEnv ( lookupLocatedBndrRn, + lookupInstDeclBndr, newIPNameRn, + lookupLocatedSigOccRn, bindPatSigTyVarsFV, + bindLocalFixities, bindSigTyVarsFV, + warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn, + bindLocatedLocalsFV, bindLocalNames, bindLocalNamesFV, + bindLocalNamesFV_WithFixities, + bindLocatedLocalsRn, + checkDupAndShadowedRdrNames ) import DynFlags ( DynFlag(..) ) -import Name ( Name, nameOccName, nameSrcLoc ) +import HscTypes (FixItem(..)) +import Name import NameEnv +import UniqFM import NameSet import PrelNames ( isUnboundName ) import RdrName ( RdrName, rdrNameOcc ) -import SrcLoc ( mkSrcSpan, Located(..), unLoc ) +import SrcLoc ( Located(..), unLoc, noLoc ) import ListSetOps ( findDupsEq ) import BasicTypes ( RecFlag(..) ) import Digraph ( SCC(..), stronglyConnComp ) @@ -46,7 +62,7 @@ import Bag import Outputable import Maybes ( orElse ) import Util ( filterOut ) -import Monad ( foldM ) +import Monad ( foldM, unless ) \end{code} -- ToDo: Put the annotations into the monad, so that they arrive in the proper @@ -155,43 +171,46 @@ it expects the global environment to contain bindings for the binders %* * %************************************************************************ -@rnTopMonoBinds@ assumes that the environment already -contains bindings for the binders of this particular binding. - \begin{code} -rnTopBinds :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses) - --- The binders of the binding are in scope already; --- the top level scope resolution does that - -rnTopBinds binds - = do { is_boot <- tcIsHsBoot - ; if is_boot then rnTopBindsBoot binds - else rnTopBindsSrc binds } - -rnTopBindsBoot :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses) +-- for top-level bindings, we need to make top-level names, +-- so we have a different entry point than for local bindings +rnTopBindsLHS :: UniqFM (Located Fixity) -- mini fixity env for the names we're about to bind + -- these fixities need to be brought into scope with the names + -> HsValBinds RdrName + -> RnM (HsValBindsLR Name RdrName) +rnTopBindsLHS fix_env binds = + (uncurry $ rnValBindsLHSFromDoc (topRecNameMaker fix_env)) (bindersAndDoc binds) binds + +rnTopBindsRHS :: [Name] -- the names bound by these binds + -> HsValBindsLR Name RdrName + -> RnM (HsValBinds Name, DefUses) +rnTopBindsRHS bound_names binds = + do { is_boot <- tcIsHsBoot + ; if is_boot + then rnTopBindsBoot binds + else rnValBindsRHSGen (\x -> x) -- don't trim free vars + bound_names binds } + + +-- wrapper if we don't need to do anything in between the left and right, +-- or anything else in the scope of the left +-- +-- never used when there are fixity declarations +rnTopBinds :: HsValBinds RdrName + -> RnM (HsValBinds Name, DefUses) +rnTopBinds b = + do nl <- rnTopBindsLHS emptyUFM b + let bound_names = map unLoc (collectHsValBinders nl) + bindLocalNames bound_names $ rnTopBindsRHS bound_names nl + + +rnTopBindsBoot :: HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) -- A hs-boot file has no bindings. -- Return a single HsBindGroup with empty binds and renamed signatures rnTopBindsBoot (ValBindsIn mbinds sigs) = do { checkErr (isEmptyLHsBinds mbinds) (bindsInHsBootFile mbinds) ; sigs' <- renameSigs okHsBootSig sigs ; return (ValBindsOut [] sigs', usesOnly (hsSigsFVs sigs')) } - -rnTopBindsSrc :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses) -rnTopBindsSrc binds@(ValBindsIn mbinds _) - = do { (binds', dus) <- rnValBinds noTrim binds - - -- Warn about missing signatures, - ; let { ValBindsOut _ sigs' = binds' - ; ty_sig_vars = mkNameSet [ unLoc n | L _ (TypeSig n _) <- sigs'] - ; un_sigd_bndrs = duDefs dus `minusNameSet` ty_sig_vars } - - ; warn_missing_sigs <- doptM Opt_WarnMissingSigs - ; ifM (warn_missing_sigs) - (mappM_ missingSigWarn (nameSetToList un_sigd_bndrs)) - - ; return (binds', dus) - } \end{code} @@ -203,33 +222,32 @@ rnTopBindsSrc binds@(ValBindsIn mbinds _) %********************************************************* \begin{code} -rnLocalBindsAndThen - :: HsLocalBinds RdrName - -> (HsLocalBinds Name -> RnM (result, FreeVars)) - -> RnM (result, FreeVars) --- This version (a) assumes that the binding vars are not already in scope --- (b) removes the binders from the free vars of the thing inside +rnLocalBindsAndThen :: HsLocalBinds RdrName + -> (HsLocalBinds Name -> RnM (result, FreeVars)) + -> RnM (result, FreeVars) +-- This version (a) assumes that the binding vars are *not* already in scope +-- (b) removes the binders from the free vars of the thing inside -- The parser doesn't produce ThenBinds rnLocalBindsAndThen EmptyLocalBinds thing_inside = thing_inside EmptyLocalBinds rnLocalBindsAndThen (HsValBinds val_binds) thing_inside = rnValBindsAndThen val_binds $ \ val_binds' -> - thing_inside (HsValBinds val_binds') + thing_inside (HsValBinds val_binds') -rnLocalBindsAndThen (HsIPBinds binds) thing_inside - = rnIPBinds binds `thenM` \ (binds',fv_binds) -> - thing_inside (HsIPBinds binds') `thenM` \ (thing, fvs_thing) -> - returnM (thing, fvs_thing `plusFV` fv_binds) +rnLocalBindsAndThen (HsIPBinds binds) thing_inside = do + (binds',fv_binds) <- rnIPBinds binds + (thing, fvs_thing) <- thing_inside (HsIPBinds binds') + return (thing, fvs_thing `plusFV` fv_binds) -------------- -rnIPBinds (IPBinds ip_binds _no_dict_binds) - = do { (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds - ; return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s) } -rnIPBind (IPBind n expr) - = newIPNameRn n `thenM` \ name -> - rnLExpr expr `thenM` \ (expr',fvExpr) -> +rnIPBinds (IPBinds ip_binds _no_dict_binds) = do + (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds + return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s) + +rnIPBind (IPBind n expr) = do + name <- newIPNameRn n + (expr',fvExpr) <- rnLExpr expr return (IPBind name expr', fvExpr) \end{code} @@ -241,68 +259,286 @@ rnIPBind (IPBind n expr) %************************************************************************ \begin{code} -rnValBindsAndThen :: HsValBinds RdrName - -> (HsValBinds Name -> RnM (result, FreeVars)) - -> RnM (result, FreeVars) - -rnValBindsAndThen binds@(ValBindsIn mbinds sigs) thing_inside - = -- 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 $ \ bndrs -> - - -- Then install local fixity declarations - -- Notice that they scope over thing_inside too - bindLocalFixities [sig | L _ (FixSig sig) <- sigs ] $ - - -- Do the business - rnValBinds (trimWith bndrs) binds `thenM` \ (binds, bind_dus) -> - - -- Now do the "thing inside" - thing_inside binds `thenM` \ (result,result_fvs) -> - - -- Final error checking +-- wrapper for local binds +-- creates the documentation info and calls the helper below +rnValBindsLHS :: UniqFM (Located Fixity) -- mini fixity env for the names we're about to bind + -- these fixities need to be brought into scope with the names + -> HsValBinds RdrName + -> RnM (HsValBindsLR Name RdrName) +rnValBindsLHS fix_env binds = + let (boundNames,doc) = bindersAndDoc binds + in rnValBindsLHSFromDoc_Local boundNames doc fix_env binds + +-- a helper used for local binds that does the duplicates check, +-- just so we don't forget to do it somewhere +rnValBindsLHSFromDoc_Local :: [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice) + -> SDoc -- doc string for dup names and shadowing + -> UniqFM (Located Fixity) -- mini fixity env for the names we're about to bind + -- these fixities need to be brought into scope with the names + -> HsValBinds RdrName + -> RnM (HsValBindsLR Name RdrName) + +rnValBindsLHSFromDoc_Local boundNames doc fix_env binds = do + -- Do error checking: we need to check for dups here because we + -- don't don't bind all of the variables from the ValBinds at once + -- with bindLocatedLocals any more. + checkDupAndShadowedRdrNames doc boundNames + + -- (Note that we don't want to do this at the top level, since + -- sorting out duplicates and shadowing there happens elsewhere. + -- The behavior is even different. For example, + -- import A(f) + -- f = ... + -- should not produce a shadowing warning (but it will produce + -- an ambiguity warning if you use f), but + -- import A(f) + -- g = let f = ... in f + -- should. + rnValBindsLHSFromDoc (localRecNameMaker fix_env) boundNames doc binds + +bindersAndDoc :: HsValBinds RdrName -> ([Located RdrName], SDoc) +bindersAndDoc binds = let - all_uses = duUses bind_dus `plusFV` result_fvs - -- 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 - - unused_bndrs = [ b | b <- bndrs, not (b `elemNameSet` all_uses)] + -- the unrenamed bndrs for error checking and reporting + orig = collectHsValBinders binds + doc = text "In the binding group for:" <+> pprWithCommas ppr (map unLoc orig) in - warnUnusedLocalBinds unused_bndrs `thenM_` + (orig, doc) + +-- renames the left-hand sides +-- generic version used both at the top level and for local binds +-- does some error checking, but not what gets done elsewhere at the top level +rnValBindsLHSFromDoc :: NameMaker + -> [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice) + -> SDoc -- doc string for dup names and shadowing + -> HsValBinds RdrName + -> RnM (HsValBindsLR Name RdrName) +rnValBindsLHSFromDoc topP original_bndrs doc binds@(ValBindsIn mbinds sigs) = do + -- rename the LHSes + mbinds' <- mapBagM (rnBindLHS topP doc) mbinds + return $ ValBindsIn mbinds' sigs + +-- assumes the LHS vars are in scope +-- general version used both from the top-level and for local things +-- +-- does not bind the local fixity declarations +rnValBindsRHSGen :: (FreeVars -> FreeVars) -- for trimming free var sets + -- The trimming function trims the free vars we attach to a + -- binding so that it stays reasonably small + -> [Name] -- names bound by the LHSes + -> HsValBindsLR Name RdrName + -> RnM (HsValBinds Name, DefUses) + +rnValBindsRHSGen trim bound_names binds@(ValBindsIn mbinds sigs) = do + -- rename the sigs + sigs' <- rename_sigs sigs + -- rename the RHSes + binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds + let (anal_binds, anal_dus) = depAnalBinds binds_w_dus + (valbind', valbind'_dus) = (ValBindsOut anal_binds sigs', + usesOnly (hsSigsFVs sigs') `plusDU` anal_dus) + -- We do the check-sigs after renaming the bindings, + -- so that we have convenient access to the binders + check_sigs (okBindSig (duDefs anal_dus)) sigs' + return (valbind', valbind'_dus) + +-- wrapper for local binds +-- +-- the *client* of this function is responsible for checking for unused binders; +-- it doesn't (and can't: we don't have the thing inside the binds) happen here +-- +-- the client is also responsible for bringing the fixities into scope +rnValBindsRHS :: [Name] -- names bound by the LHSes + -> HsValBindsLR Name RdrName + -> RnM (HsValBinds Name, DefUses) +rnValBindsRHS bound_names binds = + rnValBindsRHSGen (\ fvs -> -- only keep the names the names from this group + intersectNameSet (mkNameSet bound_names) fvs) bound_names binds - returnM (result, delListFromNameSet all_uses bndrs) - where - mbinders_w_srclocs = collectHsBindLocatedBinders mbinds - doc = text "In the binding group for:" - <+> pprWithCommas ppr (map unLoc mbinders_w_srclocs) + +-- for local binds +-- wrapper that does both the left- and right-hand sides +-- +-- here there are no local fixity decls passed in; +-- the local fixity decls come from the ValBinds sigs +rnValBindsAndThen :: HsValBinds RdrName + -> (HsValBinds Name -> RnM (result, FreeVars)) + -> RnM (result, FreeVars) +rnValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside = + let + (original_bndrs, doc) = bindersAndDoc binds + + in do + -- (A) create the local fixity environment + new_fixities <- makeMiniFixityEnv [L loc sig | L loc (FixSig sig) <- sigs] + + -- (B) rename the LHSes + new_lhs <- rnValBindsLHSFromDoc_Local original_bndrs doc new_fixities binds + let bound_names = map unLoc $ collectHsValBinders new_lhs + + -- and bring them (and their fixities) into scope + bindLocalNamesFV_WithFixities bound_names new_fixities $ + warnUnusedLocalBinds bound_names $ do + + -- (C) do the RHS and thing inside + (binds', dus) <- rnValBindsRHS bound_names new_lhs + (result, result_fvs) <- thing_inside binds' + + let + -- the variables used in the val binds are: + -- (1) the uses of the binds + -- (2) the FVs of the thing-inside + all_uses = (duUses dus) `plusFV` result_fvs + -- duUses: It's important to return all the uses. 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 + + return (result, + -- the bound names are pruned out of all_uses + -- by the bindLocalNamesFV call above + all_uses) + + +-- Process the fixity declarations, making a FastString -> (Located Fixity) map +-- (We keep the location around for reporting duplicate fixity declarations.) +-- +-- Checks for duplicates, but not that only locally defined things are fixed. +-- Note: for local fixity declarations, duplicates would also be checked in +-- check_sigs below. But we also use this function at the top level. +makeMiniFixityEnv :: [LFixitySig RdrName] + -> RnM (UniqFM (Located Fixity)) -- key is the FastString of the OccName + -- of the fixity declaration it came from + +makeMiniFixityEnv decls = foldlM add_one emptyUFM decls + where + add_one env (L loc (FixitySig (L name_loc name) fixity)) = do + { -- this fixity decl is a duplicate iff + -- the ReaderName's OccName's FastString is already in the env + -- (we only need to check the local fix_env because + -- definitions of non-local will be caught elsewhere) + let {occ = rdrNameOcc name; + curKey = occNameFS occ; + fix_item = L loc fixity}; + + case lookupUFM env curKey of + Nothing -> return $ addToUFM env curKey fix_item + Just (L loc' _) -> do + { setSrcSpan loc $ + addLocErr (L name_loc name) (dupFixityDecl loc') + ; return env} + } + +pprFixEnv :: NameEnv FixItem -> SDoc +pprFixEnv env + = pprWithCommas (\ (FixItem n f) -> ppr f <+> ppr n) + (nameEnvElts env) + +dupFixityDecl loc rdr_name + = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name), + ptext SLIT("also at ") <+> ppr loc] --------------------- -rnValBinds :: (FreeVars -> FreeVars) - -> HsValBinds RdrName - -> RnM (HsValBinds Name, DefUses) --- Assumes the binders of the binding are in scope already -rnValBinds trim (ValBindsIn mbinds sigs) - = do { sigs' <- rename_sigs sigs +-- renaming a single bind + +rnBindLHS :: NameMaker + -> SDoc + -> LHsBind RdrName + -- returns the renamed left-hand side, + -- and the FreeVars *of the LHS* + -- (i.e., any free variables of the pattern) + -> RnM (LHsBindLR Name RdrName) + +rnBindLHS name_maker doc (L loc (PatBind { pat_lhs = pat, + pat_rhs = grhss, + bind_fvs=bind_fvs, + pat_rhs_ty=pat_rhs_ty + })) + = setSrcSpan loc $ do + -- we don't actually use the FV processing of rnPatsAndThen here + (pat',pat'_fvs) <- rnBindPat name_maker pat + return (L loc (PatBind { pat_lhs = pat', + pat_rhs = grhss, + -- we temporarily store the pat's FVs here; + -- gets updated to the FVs of the whole bind + -- when doing the RHS below + bind_fvs = pat'_fvs, + -- these will get ignored in the next pass, + -- when we rename the RHS + pat_rhs_ty = pat_rhs_ty })) + +rnBindLHS name_maker doc (L loc (FunBind { fun_id = name@(L nameLoc _), + fun_infix = inf, + fun_matches = matches, + fun_co_fn = fun_co_fn, + bind_fvs = bind_fvs, + fun_tick = fun_tick + })) + = setSrcSpan loc $ + do { (newname, _fvs) <- applyNameMaker name_maker name $ \ newname -> + return (newname, emptyFVs) + ; return (L loc (FunBind { fun_id = L nameLoc newname, + fun_infix = inf, + fun_matches = matches, + -- we temporatily store the LHS's FVs (empty in this case) here + -- gets updated when doing the RHS below + bind_fvs = emptyFVs, + -- everything else will get ignored in the next pass + fun_co_fn = fun_co_fn, + fun_tick = fun_tick + })) } + +-- assumes the left-hands-side vars are in scope +rnBind :: (Name -> [Name]) -- Signature tyvar function + -> (FreeVars -> FreeVars) -- Trimming function for rhs free vars + -> LHsBindLR Name RdrName + -> RnM (LHsBind Name, [Name], Uses) +rnBind sig_fn trim (L loc (PatBind { pat_lhs = pat, + pat_rhs = grhss, + -- pat fvs were stored here while processing the LHS + bind_fvs=pat_fvs })) + = setSrcSpan loc $ + do {let bndrs = collectPatBinders pat - ; binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds + ; (grhss', fvs) <- rnGRHSs PatBindRhs grhss + -- No scoped type variables for pattern bindings - ; let (binds', bind_dus) = depAnalBinds binds_w_dus + ; return (L loc (PatBind { pat_lhs = pat, + pat_rhs = grhss', + pat_rhs_ty = placeHolderType, + bind_fvs = trim fvs }), + bndrs, pat_fvs `plusFV` fvs) } - -- We do the check-sigs after renaming the bindings, - -- so that we have convenient access to the binders - ; check_sigs (okBindSig (duDefs bind_dus)) sigs' +rnBind sig_fn + trim + (L loc (FunBind { fun_id = name, + fun_infix = inf, + fun_matches = matches, + -- no pattern FVs + bind_fvs = _ + })) + -- invariant: no free vars here when it's a FunBind + = setSrcSpan loc $ + do { let plain_name = unLoc name - ; return (ValBindsOut binds' sigs', - usesOnly (hsSigsFVs sigs') `plusDU` bind_dus) } + ; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $ + -- bindSigTyVars tests for Opt_ScopedTyVars + rnMatchGroup (FunRhs plain_name inf) matches + ; checkPrecMatch inf plain_name matches' + ; return (L loc (FunBind { fun_id = name, + fun_infix = inf, + fun_matches = matches', + bind_fvs = trim fvs, + fun_co_fn = idHsWrapper, + fun_tick = Nothing }), + [plain_name], fvs) + } + --------------------- depAnalBinds :: Bag (LHsBind Name, [Name], Uses) -> ([(RecFlag, LHsBinds Name)], DefUses) @@ -358,49 +594,6 @@ mkSigTvFn sigs (L _ (HsForAllTy Explicit ltvs _ _))) <- sigs] -- Note the pattern-match on "Explicit"; we only bind -- type variables from signatures with an explicit top-level for-all - --- The trimming function trims the free vars we attach to a --- binding so that it stays reasonably small -noTrim :: FreeVars -> FreeVars -noTrim fvs = fvs -- Used at top level - -trimWith :: [Name] -> FreeVars -> FreeVars --- Nested bindings; trim by intersection with the names bound here -trimWith bndrs = intersectNameSet (mkNameSet bndrs) - ---------------------- -rnBind :: (Name -> [Name]) -- Signature tyvar function - -> (FreeVars -> FreeVars) -- Trimming function for rhs free vars - -> LHsBind RdrName - -> RnM (LHsBind Name, [Name], Uses) -rnBind sig_fn trim (L loc (PatBind { pat_lhs = pat, pat_rhs = grhss })) - = setSrcSpan loc $ - do { (pat', pat_fvs) <- rnLPat pat - - ; let bndrs = collectPatBinders pat' - - ; (grhss', fvs) <- rnGRHSs PatBindRhs grhss - -- No scoped type variables for pattern bindings - - ; return (L loc (PatBind { pat_lhs = pat', pat_rhs = grhss', - pat_rhs_ty = placeHolderType, bind_fvs = trim fvs }), - bndrs, pat_fvs `plusFV` fvs) } - -rnBind sig_fn trim (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = matches })) - = setSrcSpan loc $ - do { new_name <- lookupLocatedBndrRn name - ; let plain_name = unLoc new_name - - ; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $ - -- bindSigTyVars tests for Opt_ScopedTyVars - rnMatchGroup (FunRhs plain_name) matches - - ; checkPrecMatch inf plain_name matches' - - ; return (L loc (FunBind { fun_id = new_name, fun_infix = inf, fun_matches = matches', - bind_fvs = trim fvs, fun_co_fn = idHsWrapper }), - [plain_name], fvs) - } \end{code} @@ -434,38 +627,41 @@ rnMethodBinds cls sig_fn gen_tyvars binds rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = MatchGroup matches _ })) - = setSrcSpan loc $ - lookupLocatedInstDeclBndr cls name `thenM` \ sel_name -> - let plain_name = unLoc sel_name in - -- We use the selector name as the binder - - bindSigTyVarsFV (sig_fn plain_name) $ - mapFvRn (rn_match plain_name) matches `thenM` \ (new_matches, fvs) -> - let - new_group = MatchGroup new_matches placeHolderType - in - checkPrecMatch inf plain_name new_group `thenM_` - returnM (unitBag (L loc (FunBind { fun_id = sel_name, fun_infix = inf, fun_matches = new_group, - bind_fvs = fvs, fun_co_fn = idHsWrapper })), - fvs `addOneFV` plain_name) - -- The 'fvs' field isn't used for method binds + = setSrcSpan loc $ do + sel_name <- lookupInstDeclBndr cls name + let plain_name = unLoc sel_name + -- We use the selector name as the binder + + bindSigTyVarsFV (sig_fn plain_name) $ do + (new_matches, fvs) <- mapFvRn (rn_match plain_name) matches + let + new_group = MatchGroup new_matches placeHolderType + + checkPrecMatch inf plain_name new_group + return (unitBag (L loc (FunBind { + fun_id = sel_name, fun_infix = inf, + fun_matches = new_group, + bind_fvs = fvs, fun_co_fn = idHsWrapper, + fun_tick = Nothing })), + fvs `addOneFV` plain_name) + -- The 'fvs' field isn't used for method binds where -- Truly gruesome; bring into scope the correct members of the generic -- type variables. See comments in RnSource.rnSourceDecl(ClassDecl) rn_match sel_name match@(L _ (Match (L _ (TypePat ty) : _) _ _)) = extendTyVarEnvFVRn gen_tvs $ - rnMatch (FunRhs sel_name) match + rnMatch (FunRhs sel_name inf) match where tvs = map (rdrNameOcc.unLoc) (extractHsTyRdrTyVars ty) gen_tvs = [tv | tv <- gen_tyvars, nameOccName tv `elem` tvs] - rn_match sel_name match = rnMatch (FunRhs sel_name) match + rn_match sel_name match = rnMatch (FunRhs sel_name inf) match -- Can't handle method pattern-bindings which bind multiple methods. -rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _)) - = addLocErr mbind methodBindErr `thenM_` - returnM (emptyBag, emptyFVs) +rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _)) = do + addLocErr mbind methodBindErr + return (emptyBag, emptyFVs) \end{code} @@ -489,25 +685,24 @@ signatures. We'd only need this if we wanted to report unused tyvars. \begin{code} renameSigs :: (LSig Name -> Bool) -> [LSig RdrName] -> RnM [LSig Name] -- Renames the signatures and performs error checks -renameSigs ok_sig sigs +renameSigs ok_sig sigs = do { sigs' <- rename_sigs sigs ; check_sigs ok_sig sigs' ; return sigs' } ---------------------- rename_sigs :: [LSig RdrName] -> RnM [LSig Name] -rename_sigs sigs = mappM (wrapLocM renameSig) - (filter (not . isFixityLSig) sigs) - -- Remove fixity sigs which have been dealt with already +rename_sigs sigs = mapM (wrapLocM renameSig) sigs ---------------------- check_sigs :: (LSig Name -> Bool) -> [LSig Name] -> RnM () -- Used for class and instance decls, as well as regular bindings -check_sigs ok_sig sigs +check_sigs ok_sig sigs = do -- Check for (a) duplicate signatures - -- (b) signatures for things not in this group - = do { mappM_ unknownSigErr (filter (not . ok_sig) sigs') - ; mappM_ dupSigDeclErr (findDupsEq eqHsSig sigs') } + -- (b) signatures for things not in this group = do + traceRn (text "SIGS" <+> ppr sigs) + mapM_ unknownSigErr (filter (not . ok_sig) sigs') + mapM_ dupSigDeclErr (findDupsEq eqHsSig sigs') where -- Don't complain about an unbound name again sigs' = filterOut bad_name sigs @@ -526,23 +721,27 @@ check_sigs ok_sig sigs renameSig :: Sig RdrName -> RnM (Sig Name) -- FixitSig is renamed elsewhere. -renameSig (TypeSig v ty) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> - returnM (TypeSig new_v new_ty) - -renameSig (SpecInstSig ty) - = rnLHsType (text "A SPECIALISE instance pragma") ty `thenM` \ new_ty -> - returnM (SpecInstSig new_ty) - -renameSig (SpecSig v ty inl) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> - returnM (SpecSig new_v new_ty inl) - -renameSig (InlineSig v s) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - returnM (InlineSig new_v s) +renameSig (TypeSig v ty) = do + new_v <- lookupLocatedSigOccRn v + new_ty <- rnHsSigType (quotes (ppr v)) ty + return (TypeSig new_v new_ty) + +renameSig (SpecInstSig ty) = do + new_ty <- rnLHsType (text "A SPECIALISE instance pragma") ty + return (SpecInstSig new_ty) + +renameSig (SpecSig v ty inl) = do + new_v <- lookupLocatedSigOccRn v + new_ty <- rnHsSigType (quotes (ppr v)) ty + return (SpecSig new_v new_ty inl) + +renameSig (InlineSig v s) = do + new_v <- lookupLocatedSigOccRn v + return (InlineSig new_v s) + +renameSig (FixSig (FixitySig v f)) = do + new_v <- lookupLocatedSigOccRn v + return (FixSig (FixitySig new_v f)) \end{code} @@ -554,9 +753,9 @@ renameSig (InlineSig v s) \begin{code} rnMatchGroup :: HsMatchContext Name -> MatchGroup RdrName -> RnM (MatchGroup Name, FreeVars) -rnMatchGroup ctxt (MatchGroup ms _) - = mapFvRn (rnMatch ctxt) ms `thenM` \ (new_ms, ms_fvs) -> - returnM (MatchGroup new_ms placeHolderType, ms_fvs) +rnMatchGroup ctxt (MatchGroup ms _) = do + (new_ms, ms_fvs) <- mapFvRn (rnMatch ctxt) ms + return (MatchGroup new_ms placeHolderType, ms_fvs) rnMatch :: HsMatchContext Name -> LMatch RdrName -> RnM (LMatch Name, FreeVars) rnMatch ctxt = wrapLocFstM (rnMatch' ctxt) @@ -564,21 +763,22 @@ rnMatch ctxt = wrapLocFstM (rnMatch' ctxt) rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss) = -- Deal with the rhs type signature - bindPatSigTyVarsFV rhs_sig_tys $ - doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts -> - (case maybe_rhs_sig of - Nothing -> returnM (Nothing, emptyFVs) - Just ty | opt_GlasgowExts -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) -> - returnM (Just ty', ty_fvs) - | otherwise -> addLocErr ty patSigErr `thenM_` - returnM (Nothing, emptyFVs) - ) `thenM` \ (maybe_rhs_sig', ty_fvs) -> - - -- Now the main event - rnPatsAndThen ctxt pats $ \ pats' -> - rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) -> - - returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) + bindPatSigTyVarsFV rhs_sig_tys $ do + opt_PatternSignatures <- doptM Opt_PatternSignatures + (maybe_rhs_sig', ty_fvs) <- + case maybe_rhs_sig of + Nothing -> return (Nothing, emptyFVs) + Just ty | opt_PatternSignatures -> do (ty', ty_fvs) <- rnHsTypeFVs doc_sig ty + return (Just ty', ty_fvs) + | otherwise -> do addLocErr ty patSigErr + return (Nothing, emptyFVs) + + -- Now the main event + -- note that there are no local ficity decls for matches + rnPatsAndThen_LocalRightwards ctxt pats $ \ pats' -> do + (grhss', grhss_fvs) <- rnGRHSs ctxt grhss + + return (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) -- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs where rhs_sig_tys = case maybe_rhs_sig of @@ -598,19 +798,19 @@ rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss) rnGRHSs :: HsMatchContext Name -> GRHSs RdrName -> RnM (GRHSs Name, FreeVars) rnGRHSs ctxt (GRHSs grhss binds) - = rnLocalBindsAndThen binds $ \ binds' -> - mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) -> - returnM (GRHSs grhss' binds', fvGRHSs) + = rnLocalBindsAndThen binds $ \ binds' -> do + (grhss', fvGRHSs) <- mapFvRn (rnGRHS ctxt) grhss + return (GRHSs grhss' binds', fvGRHSs) rnGRHS :: HsMatchContext Name -> LGRHS RdrName -> RnM (LGRHS Name, FreeVars) rnGRHS ctxt = wrapLocFstM (rnGRHS' ctxt) rnGRHS' ctxt (GRHS guards rhs) - = do { opt_GlasgowExts <- doptM Opt_GlasgowExts + = do { pattern_guards_allowed <- doptM Opt_PatternGuards ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $ rnLExpr rhs - ; checkM (opt_GlasgowExts || is_standard_guard guards') + ; unless (pattern_guards_allowed || is_standard_guard guards') (addWarn (nonStdGuardErr guards')) ; return (GRHS guards' rhs', fvs) } @@ -639,16 +839,20 @@ dupSigDeclErr sigs@(L loc sig : _) ppr_sig (L loc sig) = ppr loc <> colon <+> ppr sig unknownSigErr (L loc sig) - = addErrAt loc $ - sep [ptext SLIT("Misplaced") <+> what_it_is <> colon, ppr sig] + = do { mod <- getModule + ; addErrAt loc $ + vcat [sep [ptext SLIT("Misplaced") <+> what_it_is <> colon, ppr sig], + extra_stuff mod sig] } where what_it_is = hsSigDoc sig + extra_stuff mod (TypeSig (L _ n) _) + | nameIsLocalOrFrom mod n + = ptext SLIT("The type signature must be given where") + <+> quotes (ppr n) <+> ptext SLIT("is declared") + | otherwise + = ptext SLIT("You cannot give a type signature for an imported value") -missingSigWarn var - = addWarnAt (mkSrcSpan loc loc) $ - sep [ptext SLIT("Definition but no type signature for"), quotes (ppr var)] - where - loc = nameSrcLoc var -- TODO: make a proper span + extra_stuff mod other = empty methodBindErr mbind = hang (ptext SLIT("Pattern bindings (except simple variables) not allowed in instance declarations")) @@ -659,6 +863,6 @@ bindsInHsBootFile mbinds 2 (ppr mbinds) nonStdGuardErr guards - = hang (ptext SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)")) + = hang (ptext SLIT("accepting non-standard pattern guards (use -XPatternGuards to suppress this message)")) 4 (interpp'SP guards) \end{code}