Give the inferred type when warning of a missing type-signature (Trac #1256)

[ghc-hetmet.git] / compiler / rename / RnBinds.lhs

diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs
index 3a9bae0..d7a5952 100644 (file)
--- a/compiler/rename/RnBinds.lhs
+++ b/compiler/rename/RnBinds.lhs
@@ -12,7 +12,7 @@ they may be affected by renaming (which isn't fully worked out yet).
 module RnBinds (
        rnTopBinds, 
        rnLocalBindsAndThen, rnValBindsAndThen, rnValBinds, trimWith,
-       rnMethodBinds, renameSigs, 
+       rnMethodBinds, renameSigs, mkSigTvFn,
        rnMatchGroup, rnGRHSs
    ) where
 
@@ -178,20 +178,7 @@ rnTopBindsBoot (ValBindsIn mbinds 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)
-       }
+rnTopBindsSrc binds = rnValBinds noTrim binds
 \end{code}
 
 
@@ -379,8 +366,8 @@ rnBind sig_fn trim (L loc (PatBind { pat_lhs = pat, pat_rhs = grhss }))
 
        ; let bndrs = collectPatBinders pat'
 
-       ; (grhss', fvs) <- bindSigTyVarsFV (concatMap sig_fn bndrs) $
-                          rnGRHSs PatBindRhs grhss
+       ; (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 }), 
@@ -392,12 +379,13 @@ rnBind sig_fn trim (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches
        ; 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 = idCoercion }), 
+                                  bind_fvs = trim fvs, fun_co_fn = idHsWrapper, fun_tick = Nothing }), 
                  [plain_name], fvs)
       }
 \end{code}
@@ -420,30 +408,35 @@ a binder.
 
 \begin{code}
 rnMethodBinds :: Name                  -- Class name
+             -> (Name -> [Name])       -- Signature tyvar function
              -> [Name]                 -- Names for generic type variables
              -> LHsBinds RdrName
              -> RnM (LHsBinds Name, FreeVars)
 
-rnMethodBinds cls gen_tyvars binds
+rnMethodBinds cls sig_fn gen_tyvars binds
   = foldM do_one (emptyBag,emptyFVs) (bagToList binds)
   where do_one (binds,fvs) bind = do
-          (bind', fvs_bind) <- rnMethodBind cls gen_tyvars bind
+          (bind', fvs_bind) <- rnMethodBind cls sig_fn gen_tyvars bind
           return (bind' `unionBags` binds, fvs_bind `plusFV` fvs)
 
-rnMethodBind cls 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
+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 = idCoercion })), 
+    returnM (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
@@ -460,12 +453,13 @@ rnMethodBind cls gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf,
 
 
 -- Can't handle method pattern-bindings which bind multiple methods.
-rnMethodBind cls gen_tyvars mbind@(L loc (PatBind other_pat _ _ _))
+rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _))
   = addLocErr mbind methodBindErr      `thenM_`
     returnM (emptyBag, emptyFVs) 
 \end{code}
 
 
+
 %************************************************************************
 %*                                                                     *
 \subsubsection[dep-Sigs]{Signatures (and user-pragmas for values)}
@@ -640,12 +634,6 @@ unknownSigErr (L loc sig)
   where
     what_it_is = hsSigDoc sig
 
-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
-
 methodBindErr mbind
  =  hang (ptext SLIT("Pattern bindings (except simple variables) not allowed in instance declarations"))
        2 (ppr mbind)