%
-% (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}
they may be affected by renaming (which isn't fully worked out yet).
\begin{code}
-#include "HsVersions.h"
-
module RnBinds (
rnTopBinds, rnTopMonoBinds,
- rnMethodBinds,
- rnBinds, rnMonoBinds
+ rnMethodBinds, renameSigs, renameSigsFVs,
+ rnBinds,
+ 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, sigName, hsSigDoc )
import RdrHsSyn
import RnHsSyn
import RnMonad
-import RnExpr ( rnMatch, rnGRHSsAndBinds, rnPat, checkPrecMatch )
-import RnEnv ( bindLocatedLocalsRn, lookupRn, lookupOccRn, isUnboundName )
-
-import CmdLineOpts ( opt_SigsRequired )
-import Digraph ( stronglyConnComp )
-import ErrUtils ( addErrLoc, addShortErrLocLine )
-import Name ( OccName(..), Provenance,
- Name {- instance Eq -},
- NameSet(..), emptyNameSet, mkNameSet, unionNameSets,
- minusNameSet, unionManyNameSets, elemNameSet, unitNameSet, nameSetToList
+import RnTypes ( rnHsSigType, rnHsType )
+import RnExpr ( rnMatch, rnGRHSs, rnPat, checkPrecMatch )
+import RnEnv ( bindLocatedLocalsRn, lookupBndrRn,
+ lookupGlobalOccRn, lookupSigOccRn,
+ warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn,
)
-import Maybes ( catMaybes )
---import PprStyle--ToDo:rm
-import Pretty
-import Util ( thenCmp, isIn, removeDups, panic, panic#, assertPanic )
-import UniqSet ( SYN_IE(UniqSet) )
-import ListSetOps ( minusList )
-import Bag ( bagToList )
-import UniqFM ( UniqFM )
-import ErrUtils ( SYN_IE(Error) )
+import CmdLineOpts ( DynFlag(..) )
+import Digraph ( stronglyConnComp, SCC(..) )
+import Name ( Name, nameOccName, nameSrcLoc )
+import NameSet
+import RdrName ( RdrName, rdrNameOcc )
+import BasicTypes ( RecFlag(..) )
+import List ( partition )
+import Outputable
+import PrelNames ( isUnboundName )
\end{code}
-- ToDo: Put the annotations into the monad, so that they arrive in the proper
\begin{code}
type VertexTag = Int
-type Cycle = [VertexTag]
-type Edge = (VertexTag, VertexTag)
\end{code}
%************************************************************************
%************************************************************************
%* *
-%* Top-level bindings
+\subsubsection{ Top-level bindings}
%* *
%************************************************************************
contains bindings for the binders of this particular binding.
\begin{code}
-rnTopBinds :: RdrNameHsBinds -> RnMS s RenamedHsBinds
+rnTopBinds :: RdrNameHsBinds -> RnMS (RenamedHsBinds, FreeVars)
-rnTopBinds EmptyBinds = returnRn EmptyBinds
-rnTopBinds (SingleBind (RecBind bind)) = rnTopMonoBinds bind []
-rnTopBinds (BindWith (RecBind bind) sigs) = rnTopMonoBinds bind sigs
+rnTopBinds EmptyBinds = returnRn (EmptyBinds, emptyFVs)
+rnTopBinds (MonoBind bind sigs _) = rnTopMonoBinds bind sigs
-- The parser doesn't produce other forms
-rnTopMonoBinds EmptyMonoBinds sigs
- = returnRn EmptyBinds
-
rnTopMonoBinds mbinds sigs
- = mapRn lookupRn binder_rdr_names `thenRn` \ binder_names ->
+ = mapRn lookupBndrRn binder_rdr_names `thenRn` \ binder_names ->
let
- binder_set = mkNameSet binder_names
+ bndr_name_set = mkNameSet binder_names
in
- rn_mono_binds True {- top level -}
- binder_set mbinds sigs `thenRn` \ (new_binds, fv_set) ->
- returnRn new_binds
+ renameSigsFVs (okBindSig bndr_name_set) sigs `thenRn` \ (siglist, sig_fvs) ->
+
+ ifOptRn Opt_WarnMissingSigs (
+ let
+ type_sig_vars = [n | Sig n _ _ <- siglist]
+ un_sigd_binders = nameSetToList (delListFromNameSet bndr_name_set type_sig_vars)
+ in
+ mapRn_ missingSigWarn un_sigd_binders
+ ) `thenRn_`
+
+ rn_mono_binds siglist mbinds `thenRn` \ (final_binds, bind_fvs) ->
+ returnRn (final_binds, bind_fvs `plusFV` sig_fvs)
where
- binder_rdr_names = map fst (bagToList (collectMonoBinders mbinds))
+ binder_rdr_names = collectMonoBinders mbinds
\end{code}
%************************************************************************
%* *
%************************************************************************
-@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
+\subsubsection{Nested binds}
+@rnMonoBinds@
+\begin{itemize}
+\item collects up the binders for this declaration group,
+\item checks that they form a set
+\item extends the environment to bind them to new local names
+\item calls @rnMonoBinds@ to do the real work
+\end{itemize}
+%
\begin{code}
rnBinds :: RdrNameHsBinds
- -> (RenamedHsBinds -> RnMS s (result, FreeVars))
- -> RnMS s (result, FreeVars)
+ -> (RenamedHsBinds -> RnMS (result, FreeVars))
+ -> RnMS (result, FreeVars)
-rnBinds EmptyBinds thing_inside = thing_inside EmptyBinds
-rnBinds (SingleBind (RecBind bind)) thing_inside = rnMonoBinds bind [] thing_inside
-rnBinds (BindWith (RecBind bind) sigs) thing_inside = rnMonoBinds bind sigs thing_inside
+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
-rnMonoBinds :: RdrNameMonoBinds -> [RdrNameSig]
- -> (RenamedHsBinds -> RnMS s (result, FreeVars))
- -> RnMS s (result, FreeVars)
-
-rnMonoBinds EmptyMonoBinds sigs thing_inside = thing_inside EmptyBinds
+rnMonoBinds :: RdrNameMonoBinds
+ -> [RdrNameSig]
+ -> (RenamedHsBinds -> RnMS (result, FreeVars))
+ -> RnMS (result, FreeVars)
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 "binding group" mbinders_w_srclocs $ \ new_mbinders ->
+ bindLocatedLocalsRn (text "In a binding group")
+ mbinders_w_srclocs $ \ new_mbinders ->
let
binder_set = mkNameSet new_mbinders
in
- rn_mono_binds False {- not top level -}
- binder_set mbinds sigs `thenRn` \ (binds,bind_fvs) ->
+ -- Rename the signatures
+ renameSigsFVs (okBindSig binder_set) sigs `thenRn` \ (siglist, sig_fvs) ->
- -- Now do the "thing inside", and deal with the free-variable calculations
- thing_inside binds `thenRn` \ (result,result_fvs) ->
- returnRn (result, (result_fvs `unionNameSets` bind_fvs) `minusNameSet` binder_set)
+ -- Report the fixity declarations in this group that
+ -- don't refer to any of the group's binders.
+ -- Then install the fixity declarations that do apply here
+ -- Notice that they scope over thing_inside too
+ let
+ fixity_sigs = [(name,sig) | FixSig sig@(FixitySig name _ _) <- siglist ]
+ in
+ extendFixityEnv fixity_sigs $
+
+ rn_mono_binds siglist mbinds `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 `plusFV` sig_fvs
+ unused_binders = nameSetToList (binder_set `minusNameSet` all_fvs)
+ in
+ warnUnusedLocalBinds unused_binders `thenRn_`
+ returnRn (result, delListFromNameSet all_fvs new_mbinders)
where
- mbinders_w_srclocs = bagToList (collectMonoBinders mbinds)
+ mbinders_w_srclocs = collectLocatedMonoBinders mbinds
\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).
+@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).
\begin{code}
-rn_mono_binds :: Bool -- True <=> top level
- -> NameSet -- Binders of this group
+rn_mono_binds :: [RenamedSig] -- Signatures attached to this group
-> RdrNameMonoBinds
- -> [RdrNameSig] -- Signatures attached to this group
- -> RnMS s (RenamedHsBinds, --
- FreeVars) -- Free variables
+ -> RnMS (RenamedHsBinds, -- Dependency analysed
+ FreeVars) -- Free variables
-rn_mono_binds is_top_lev binders mbinds sigs
+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
- rnBindSigs is_top_lev binders sigs `thenRn` \ siglist ->
- flattenMonoBinds 0 siglist mbinds `thenRn` \ (_, mbinds_info) ->
+ flattenMonoBinds siglist mbinds `thenRn` \ mbinds_info ->
-- Do the SCC analysis
- let vertices = mkVertices mbinds_info
- edges = mkEdges mbinds_info
- scc_result = stronglyConnComp (==) edges vertices
- final_binds = foldr1 ThenBinds (map (reconstructCycle edges mbinds_info) scc_result)
+ let
+ edges = mkEdges (mbinds_info `zip` [(0::Int)..])
+ scc_result = stronglyConnComp edges
+ final_binds = foldr (ThenBinds . reconstructCycle) EmptyBinds scc_result
-- Deal with bound and free-var calculation
- rhs_fvs = unionManyNameSets [fvs | (_,_,fvs,_,_) <- mbinds_info]
+ rhs_fvs = plusFVs [fvs | (_,fvs,_,_) <- mbinds_info]
in
returnRn (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
- -> RnMS s (Int, FlatMonoBindsInfo)
+ -> RnMS [FlatMonoBindsInfo]
-flattenMonoBinds uniq sigs EmptyMonoBinds = returnRn (uniq, [])
+flattenMonoBinds sigs EmptyMonoBinds = returnRn []
-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 `thenRn` \ flat1 ->
+ flattenMonoBinds sigs bs2 `thenRn` \ flat2 ->
+ returnRn (flat1 ++ flat2)
-flattenMonoBinds uniq sigs (PatMonoBind pat grhss_and_binds locn)
+flattenMonoBinds sigs (PatMonoBind pat grhss locn)
= pushSrcLocRn locn $
- rnPat pat `thenRn` \ pat' ->
- rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) ->
+ rnPat pat `thenRn` \ (pat', pat_fvs) ->
-- Find which things are bound in this group
let
names_bound_here = mkNameSet (collectPatBinders pat')
- sigs_for_me = filter ((`elemNameSet` names_bound_here) . sig_name) sigs
- sigs_fvs = foldr sig_fv emptyNameSet sigs_for_me
in
- returnRn (
- uniq + 1,
- [(uniq,
- names_bound_here,
- fvs `unionNameSets` sigs_fvs,
- PatMonoBind pat' grhss_and_binds' locn,
+ sigsForMe names_bound_here sigs `thenRn` \ sigs_for_me ->
+ rnGRHSs grhss `thenRn` \ (grhss', fvs) ->
+ returnRn
+ [(names_bound_here,
+ fvs `plusFV` pat_fvs,
+ PatMonoBind pat' grhss' locn,
sigs_for_me
)]
- )
-flattenMonoBinds uniq sigs (FunMonoBind name inf matches locn)
- = pushSrcLocRn locn $
- mapRn (checkPrecMatch inf name) matches `thenRn_`
- lookupRn name `thenRn` \ name' ->
- mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, fv_lists) ->
+flattenMonoBinds sigs (FunMonoBind name inf matches locn)
+ = pushSrcLocRn locn $
+ lookupBndrRn name `thenRn` \ new_name ->
let
- fvs = unionManyNameSets fv_lists
- sigs_for_me = filter ((name' ==) . sig_name) sigs
- sigs_fvs = foldr sig_fv emptyNameSet sigs_for_me
+ names_bound_here = unitNameSet new_name
in
- returnRn (
- uniq + 1,
- [(uniq,
- unitNameSet name',
- fvs `unionNameSets` sigs_fvs,
- FunMonoBind name' inf new_matches locn,
+ sigsForMe names_bound_here sigs `thenRn` \ sigs_for_me ->
+ mapFvRn (rnMatch (FunRhs name)) matches `thenRn` \ (new_matches, fvs) ->
+ mapRn_ (checkPrecMatch inf new_name) new_matches `thenRn_`
+ returnRn
+ [(unitNameSet new_name,
+ fvs,
+ FunMonoBind new_name inf new_matches locn,
sigs_for_me
)]
- )
+
+
+sigsForMe names_bound_here sigs
+ = foldlRn check [] (filter (sigForThisGroup names_bound_here) sigs)
+ where
+ check sigs sig = case filter (eqHsSig sig) sigs of
+ [] -> returnRn (sig:sigs)
+ other -> dupSigDeclErr sig `thenRn_`
+ returnRn 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
+rnMethodBinds :: [Name] -- Names for generic type variables
+ -> RdrNameMonoBinds
+ -> RnMS (RenamedMonoBinds, FreeVars)
-rnMethodBinds EmptyMonoBinds = returnRn EmptyMonoBinds
+rnMethodBinds gen_tyvars EmptyMonoBinds = returnRn (EmptyMonoBinds, emptyFVs)
-rnMethodBinds (AndMonoBinds mb1 mb2)
- = andRn AndMonoBinds (rnMethodBinds mb1)
- (rnMethodBinds mb2)
+rnMethodBinds gen_tyvars (AndMonoBinds mb1 mb2)
+ = rnMethodBinds gen_tyvars mb1 `thenRn` \ (mb1', fvs1) ->
+ rnMethodBinds gen_tyvars mb2 `thenRn` \ (mb2', fvs2) ->
+ returnRn (mb1' `AndMonoBinds` mb2', fvs1 `plusFV` fvs2)
-rnMethodBinds (FunMonoBind occname inf matches locn)
- = pushSrcLocRn locn $
- mapRn (checkPrecMatch inf occname) matches `thenRn_`
- lookupRn occname `thenRn` \ op_name ->
- mapAndUnzipRn rnMatch matches `thenRn` \ (new_matches, _) ->
- returnRn (FunMonoBind op_name inf new_matches locn)
+rnMethodBinds gen_tyvars (FunMonoBind name inf matches locn)
+ = pushSrcLocRn locn $
-rnMethodBinds (PatMonoBind (VarPatIn occname) grhss_and_binds locn)
- = pushSrcLocRn locn $
- lookupRn occname `thenRn` \ op_name ->
- rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', _) ->
- returnRn (PatMonoBind (VarPatIn op_name) grhss_and_binds' locn)
+ lookupGlobalOccRn name `thenRn` \ sel_name ->
+ -- We use the selector name as the binder
+
+ mapFvRn rn_match matches `thenRn` \ (new_matches, fvs) ->
+ mapRn_ (checkPrecMatch inf sel_name) new_matches `thenRn_`
+ returnRn (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 match@(Match _ (TypePatIn ty : _) _ _)
+ = extendTyVarEnvFVRn gen_tvs (rnMatch (FunRhs name) match)
+ where
+ tvs = map rdrNameOcc (extractHsTyRdrNames ty)
+ gen_tvs = [tv | tv <- gen_tyvars, nameOccName tv `elem` tvs]
+
+ rn_match match = rnMatch (FunRhs name) match
+
-- Can't handle method pattern-bindings which bind multiple methods.
-rnMethodBinds mbind@(PatMonoBind other_pat _ locn)
+rnMethodBinds gen_tyvars mbind@(PatMonoBind other_pat _ locn)
= pushSrcLocRn locn $
- failWithRn EmptyMonoBinds (methodBindErr mbind)
+ failWithRn (EmptyMonoBinds, emptyFVs) (methodBindErr mbind)
\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 `unionNameSets` (unitNameSet blah)
-sig_fv _ acc = acc
-\end{code}
%************************************************************************
%* *
as the two cases are similar.
\begin{code}
-reconstructCycle :: [Edge] -- Original edges
- -> FlatMonoBindsInfo
- -> Cycle
+reconstructCycle :: SCC FlatMonoBindsInfo
-> RenamedHsBinds
-reconstructCycle edges mbi cycle
- = mk_binds this_gp_binds this_gp_sigs (isCyclic edges cycle)
+reconstructCycle (AcyclicSCC (_, _, binds, sigs))
+ = MonoBind binds sigs NonRecursive
+
+reconstructCycle (CyclicSCC cycle)
+ = MonoBind this_gp_binds this_gp_sigs Recursive
where
- relevant_binds_and_sigs = [(binds,sigs) | (vertex, _, _, binds, sigs) <- mbi,
- vertex `is_elem` cycle]
- (binds, sig_lists) = unzip relevant_binds_and_sigs
- this_gp_binds = foldr1 AndMonoBinds binds
- this_gp_sigs = foldr1 (++) sig_lists
-
- is_elem = isIn "reconstructRec"
-
- mk_binds :: RenamedMonoBinds -> [RenamedSig] -> Bool -> RenamedHsBinds
- mk_binds bs [] True = SingleBind (RecBind bs)
- mk_binds bs ss True = BindWith (RecBind bs) ss
- mk_binds bs [] False = SingleBind (NonRecBind bs)
- mk_binds bs ss False = 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
+ this_gp_binds = foldr1 AndMonoBinds [binds | (_, _, binds, _) <- cycle]
+ this_gp_sigs = foldr1 (++) [sigs | (_, _, _, sigs) <- cycle]
\end{code}
%************************************************************************
%* *
-%* Manipulating FlatMonoBindInfo *
+\subsubsection{ Manipulating FlatMonoBindInfo}
%* *
%************************************************************************
\begin{code}
type FlatMonoBindsInfo
- = [(VertexTag, -- Identifies the vertex
- NameSet, -- Set of names defined in this vertex
- NameSet, -- 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]
+ = (NameSet, -- Set of names defined in this vertex
+ NameSet, -- Set of names used in this vertex
+ RenamedMonoBinds,
+ [RenamedSig]) -- Signatures, if any, for this vertex
-mkVertices info = [ vertex | (vertex,_,_,_,_) <- info]
+mkEdges :: [(FlatMonoBindsInfo, VertexTag)] -> [(FlatMonoBindsInfo, VertexTag, [VertexTag])]
-mkEdges flat_info -- An edge (v,v') indicates that v depends on v'
- = [ (source_vertex, target_vertex)
- | (source_vertex, _, used_names, _, _) <- flat_info,
- target_name <- nameSetToList used_names,
- target_vertex <- vertices_defining target_name flat_info
+mkEdges flat_info
+ = [ (info, tag, dest_vertices (nameSetToList names_used))
+ | (info@(names_defined, names_used, mbind, sigs), tag) <- flat_info
]
- 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 `elemNameSet` names_defined
- ]
+ where
+ -- 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
+ ]
\end{code}
%* *
%************************************************************************
-@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
- -> NameSet -- Set of names bound in this group
+renameSigsFVs ok_sig sigs
+ = renameSigs ok_sig sigs `thenRn` \ sigs' ->
+ returnRn (sigs', hsSigsFVs sigs')
+
+renameSigs :: (RenamedSig -> Bool) -- OK-sig predicate
-> [RdrNameSig]
- -> RnMS s [RenamedSig] -- List of Sig constructors
+ -> RnMS [RenamedSig]
+
+renameSigs ok_sig [] = returnRn []
-rnBindSigs is_toplev binders sigs
+renameSigs ok_sig sigs
= -- Rename the signatures
mapRn renameSig sigs `thenRn` \ 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 (filter (not.isUnboundName.sig_name) sigs')
- not_this_group = filter (\sig -> not (sig_name sig `elemNameSet` binders)) goodies
- type_sig_vars = [n | Sig n _ _ <- goodies]
- un_sigd_binders
- | is_toplev && opt_SigsRequired = nameSetToList binders `minusList` type_sig_vars
- | otherwise = []
+ in_scope = filter is_in_scope sigs'
+ is_in_scope sig = case sigName sig of
+ Just n -> not (isUnboundName n)
+ Nothing -> True
+ (goods, bads) = partition ok_sig in_scope
in
- mapRn dupSigDeclErr dups `thenRn_`
- mapRn unknownSigErr not_this_group `thenRn_`
- mapRn (addErrRn.missingSigErr) un_sigd_binders `thenRn_`
-
- returnRn sigs' -- bad ones and all:
- -- we need bindings of *some* sort for every name
-
-
+ mapRn_ unknownSigErr bads `thenRn_`
+ returnRn goods
+
+-- 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.
+
+renameSig :: Sig RdrName -> RnMS (Sig Name)
+-- ClassOpSig is renamed elsewhere.
renameSig (Sig v ty src_loc)
= pushSrcLocRn src_loc $
- lookupRn v `thenRn` \ new_v ->
- rnHsType ty `thenRn` \ new_ty ->
+ lookupSigOccRn v `thenRn` \ new_v ->
+ rnHsSigType (quotes (ppr v)) ty `thenRn` \ new_ty ->
returnRn (Sig new_v new_ty src_loc)
-renameSig (SpecSig v ty using src_loc)
+renameSig (SpecInstSig ty src_loc)
= pushSrcLocRn src_loc $
- lookupRn v `thenRn` \ new_v ->
- rnHsType 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)
+ rnHsType (text "A SPECIALISE instance pragma") ty `thenRn` \ new_ty ->
+ returnRn (SpecInstSig new_ty src_loc)
-renameSig (InlineSig v src_loc)
+renameSig (SpecSig v ty src_loc)
= pushSrcLocRn src_loc $
- lookupRn v `thenRn` \ new_v ->
- returnRn (InlineSig new_v src_loc)
+ lookupSigOccRn v `thenRn` \ new_v ->
+ rnHsSigType (quotes (ppr v)) ty `thenRn` \ new_ty ->
+ returnRn (SpecSig new_v new_ty src_loc)
-renameSig (DeforestSig v src_loc)
+renameSig (FixSig (FixitySig v fix src_loc))
= pushSrcLocRn src_loc $
- lookupRn v `thenRn` \ new_v ->
- returnRn (DeforestSig new_v src_loc)
+ lookupSigOccRn v `thenRn` \ new_v ->
+ returnRn (FixSig (FixitySig new_v fix src_loc))
-renameSig (MagicUnfoldingSig v str src_loc)
+renameSig (InlineSig v p src_loc)
= pushSrcLocRn src_loc $
- lookupRn v `thenRn` \ new_v ->
- returnRn (MagicUnfoldingSig new_v str src_loc)
-\end{code}
-
-Checking for distinct signatures; oh, so boring
+ lookupSigOccRn v `thenRn` \ new_v ->
+ returnRn (InlineSig new_v p src_loc)
-\begin{code}
-cmp_sig :: RenamedSig -> RenamedSig -> TAG_
-cmp_sig (Sig n1 _ _) (Sig n2 _ _) = n1 `cmp` n2
-cmp_sig (InlineSig n1 _) (InlineSig n2 _) = n1 `cmp` n2
-cmp_sig (MagicUnfoldingSig n1 _ _) (MagicUnfoldingSig n2 _ _) = n1 `cmp` n2
-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 `cmp` n2) (cmpHsType cmp 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 (MagicUnfoldingSig n1 _ _) = ILIT(4)
-sig_tag (DeforestSig n1 _) = ILIT(5)
-sig_tag _ = panic# "tag(RnBinds)"
-
-sig_name (Sig n _ _) = n
-sig_name (ClassOpSig n _ _ _) = n
-sig_name (SpecSig n _ _ _) = n
-sig_name (InlineSig n _) = n
-sig_name (MagicUnfoldingSig n _ _) = n
+renameSig (NoInlineSig v p src_loc)
+ = pushSrcLocRn src_loc $
+ lookupSigOccRn v `thenRn` \ new_v ->
+ returnRn (NoInlineSig new_v p src_loc)
\end{code}
+
%************************************************************************
%* *
\subsection{Error messages}
%************************************************************************
\begin{code}
-dupSigDeclErr (sig:sigs)
+dupSigDeclErr sig
= pushSrcLocRn loc $
- addErrRn (\sty -> ppSep [ppStr "more than one",
- ppStr what_it_is, ppStr "given for",
- ppQuote (ppr sty (sig_name sig))])
+ addErrRn (sep [ptext SLIT("Duplicate") <+> ptext what_it_is <> colon,
+ ppr sig])
where
- (what_it_is, loc) = sig_doc sig
+ (what_it_is, loc) = hsSigDoc sig
unknownSigErr sig
= pushSrcLocRn loc $
- addErrRn (\sty -> ppSep [ppStr flavour, ppStr "but no definition for",
- ppQuote (ppr sty (sig_name sig))])
+ addErrRn (sep [ptext SLIT("Misplaced") <+> ptext what_it_is <> colon,
+ ppr sig])
where
- (flavour, loc) = sig_doc sig
-
-sig_doc (Sig _ _ loc) = ("type signature",loc)
-sig_doc (ClassOpSig _ _ _ loc) = ("class-method type signature", loc)
-sig_doc (SpecSig _ _ _ loc) = ("SPECIALIZE pragma",loc)
-sig_doc (InlineSig _ loc) = ("INLINE pragma",loc)
-sig_doc (MagicUnfoldingSig _ _ loc) = ("MAGIC_UNFOLDING pragma",loc)
+ (what_it_is, loc) = hsSigDoc sig
-missingSigErr var sty
- = ppSep [ppStr "a definition but no type signature for", ppQuote (ppr sty var)]
+missingSigWarn var
+ = pushSrcLocRn (nameSrcLoc var) $
+ addWarnRn (sep [ptext SLIT("Definition but no type signature for"), quotes (ppr var)])
-methodBindErr mbind sty
- = ppHang (ppStr "Can't handle multiple methods defined by one pattern binding")
- 4 (ppr sty mbind)
+methodBindErr mbind
+ = hang (ptext SLIT("Can't handle multiple methods defined by one pattern binding"))
+ 4 (ppr mbind)
\end{code}