import RnTypes ( rnHsSigType, rnHsType, rnPat )
import RnExpr ( rnMatch, rnGRHSs, checkPrecMatch )
import RnEnv ( bindLocatedLocalsRn, lookupBndrRn, lookupInstDeclBndr,
- lookupSigOccRn, bindPatSigTyVars, bindLocalFixities,
+ lookupSigOccRn, bindPatSigTyVars, bindPatSigTyVarsFV,
+ bindLocalFixities,
warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn,
)
import CmdLineOpts ( DynFlag(..) )
import Name ( Name, nameOccName, nameSrcLoc )
import NameSet
import RdrName ( RdrName, rdrNameOcc )
-import BasicTypes ( RecFlag(..) )
+import BasicTypes ( RecFlag(..), TopLevelFlag(..), isTopLevel )
import List ( unzip4 )
import Outputable
\end{code}
\begin{code}
rnTopMonoBinds :: RdrNameMonoBinds
-> [RdrNameSig]
- -> RnM (RenamedHsBinds, FreeVars)
+ -> RnM (RenamedHsBinds, DefUses)
--- Assumes the binders of the binding are in scope already
--- Very like rnMonoBinds, but checks for missing signatures too
+-- The binders of the binding are in scope already;
+-- the top level scope resoluttion does that
rnTopMonoBinds mbinds sigs
- = bindPatSigTyVars (collectSigTysFromMonoBinds 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
- 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_`
-
- returnM (final_binds, bind_fvs `plusFV` hsSigsFVs siglist)
+ rnMonoBinds TopLevel mbinds sigs
\end{code}
= -- 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) $
+ 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 ] $
-- Do the business
- rnMonoBinds mbinds sigs `thenM` \ (binds, bind_fvs) ->
+ rnMonoBinds NotTopLevel mbinds sigs `thenM` \ (binds, bind_dus) ->
-- Now do the "thing inside"
thing_inside binds `thenM` \ (result,result_fvs) ->
-- Final error checking
let
- all_fvs = result_fvs `plusFV` bind_fvs
- unused_binders = filter (not . (`elemNameSet` all_fvs)) new_mbinders
+ bndrs = duDefs bind_dus
+ all_uses = findUses bind_dus result_fvs
+ unused_bndrs = nameSetToList (bndrs `minusNameSet` all_uses)
in
- warnUnusedLocalBinds unused_binders `thenM_`
+ warnUnusedLocalBinds unused_bndrs `thenM_`
- returnM (result, delListFromNameSet all_fvs new_mbinders)
+ returnM (result, all_uses `minusNameSet` bndrs)
where
mbinders_w_srclocs = collectLocatedMonoBinders mbinds
doc = text "In the binding group for:"
\end{code}
-\begin{code}
-rnMonoBinds :: RdrNameMonoBinds
- -> [RdrNameSig]
- -> RnM (RenamedHsBinds, FreeVars)
-
--- Assumes the binders of the binding are in scope already
-
-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}
-
%************************************************************************
%* *
\subsubsection{ MonoBinds -- the main work is done here}
%* *
%************************************************************************
-@rn_mono_binds@ is used by {\em both} top-level and nested bindings.
+@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 :: [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
+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
- flattenMonoBinds siglist mbinds `thenM` \ mbinds_info ->
+ flattenMonoBinds siglist mbinds `thenM` \ mbinds_info ->
-- Do the SCC analysis
let
scc_result = rnSCC mbinds_info
- (binds_s, rhs_fvs_s) = unzip (map reconstructCycle scc_result)
+ (binds_s, bind_dus_s) = unzip (map reconstructCycle scc_result)
+ bind_dus = mkDUs bind_dus_s
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]
+ binders = duDefs bind_dus
in
- returnM (bndrs, 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.)
+ getModeRn `thenM` \ mode ->
+ doptM Opt_WarnMissingSigs `thenM` \ warn_missing_sigs ->
+ (if isTopLevel top_lvl &&
+ 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_`
+
+ returnM (final_binds, bind_dus `plusDU` usesOnly (hsSigsFVs siglist))
\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 :: [RenamedSig] -- Signatures
-> RdrNameMonoBinds
renamed.
\begin{code}
-
-type Defs = NameSet
-type Uses = NameSet
type FlatMonoBinds = (Defs, Uses, RenamedMonoBinds, [RenamedSig])
-- Signatures, if any, for this vertex
defs `intersectsNameSet` uses
]
-reconstructCycle :: SCC FlatMonoBinds -> (RenamedHsBinds, Uses)
+reconstructCycle :: SCC FlatMonoBinds -> (RenamedHsBinds, (Defs,Uses))
reconstructCycle (AcyclicSCC (defs, uses, binds, sigs))
- = (MonoBind binds sigs NonRecursive, uses)
+ = (MonoBind binds sigs NonRecursive, (defs, 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
+ (unionManyNameSets defs_s, unionManyNameSets uses_s))
where
(defs_s, uses_s, binds_s, sigs_s) = unzip4 cycle
this_gp_binds = foldr1 AndMonoBinds binds_s
signatures. We'd only need this if we wanted to report unused tyvars.
\begin{code}
-checkSigs :: (NameSet -> RenamedSig -> Bool) -- OK-sig predicbate
- -> NameSet -- Binders of this group
+checkSigs :: (RenamedSig -> Bool) -- OK-sig predicbate
-> [RenamedSig]
-> RnM ()
-checkSigs ok_sig bndrs sigs
+checkSigs ok_sig sigs
-- Check for (a) duplicate signatures
-- (b) signatures for things not in this group
- -- Well, I can't see the check for (b)... ToDo!
+ -- Well, I can't see the check for (a)... ToDo!
= mappM_ unknownSigErr bad_sigs
where
- bad_sigs = filter (not . ok_sig bndrs) sigs
+ bad_sigs = filter (not . ok_sig) sigs
-- We use lookupSigOccRn in the signatures, which is a little bit unsatisfactory
-- because this won't work for: