Make TcUnify warning-free

[ghc-hetmet.git] / compiler / basicTypes / DataCon.lhs

diff --git a/compiler/basicTypes/DataCon.lhs b/compiler/basicTypes/DataCon.lhs
index 0c6e3c5..e5a624f 100644 (file)
--- a/compiler/basicTypes/DataCon.lhs
+++ b/compiler/basicTypes/DataCon.lhs
@@ -338,19 +338,21 @@ data DataCon
        dcRepTyCon  :: TyCon,           -- Result tycon, T
 
        dcRepType   :: Type,    -- Type of the constructor
-                               --      forall a x y. (a:=:(x,y), Ord x) => x -> y -> MkT a
+                               --      forall a x y. (a:=:(x,y), x~y, Ord x) =>
+                                --        x -> y -> T a
                                -- (this is *not* of the constructor wrapper Id:
                                --  see Note [Data con representation] below)
        -- Notice that the existential type parameters come *second*.  
        -- Reason: in a case expression we may find:
-       --      case (e :: T t) of { MkT b (d:Ord b) (x:t) (xs:[b]) -> ... }
+       --      case (e :: T t) of
+        --        MkT x y co1 co2 (d:Ord x) (v:r) (w:F s) -> ...
        -- It's convenient to apply the rep-type of MkT to 't', to get
-       --      forall b. Ord b => ...
+       --      forall x y. (t:=:(x,y), x~y, Ord x) => x -> y -> T t
        -- and use that to check the pattern.  Mind you, this is really only
-       -- use in CoreLint.
+       -- used in CoreLint.
 
 
-       -- Finally, the curried worker function that corresponds to the constructor
+       -- The curried worker function that corresponds to the constructor:
        -- It doesn't have an unfolding; the code generator saturates these Ids
        -- and allocates a real constructor when it finds one.
        --
@@ -376,7 +378,7 @@ data DataConIds
        -- The 'Nothing' case of DCIds is important
        -- Not only is this efficient,
        -- but it also ensures that the wrapper is replaced
-       -- by the worker (becuase it *is* the worker)
+       -- by the worker (because it *is* the worker)
        -- even when there are no args. E.g. in
        --              f (:) x
        -- the (:) *is* the worker.
@@ -676,7 +678,7 @@ dataConInstArgTys dc@(MkData {dcRepArgTys = rep_arg_tys,
                              dcUnivTyVars = univ_tvs, dcEqSpec = eq_spec,
                              dcExTyVars = ex_tvs}) inst_tys
  = ASSERT2 ( length univ_tvs == length inst_tys 
-           , ptext SLIT("dataConInstArgTys") <+> ppr dc $$ ppr univ_tvs $$ ppr inst_tys)
+           , ptext (sLit "dataConInstArgTys") <+> ppr dc $$ ppr univ_tvs $$ ppr inst_tys)
    ASSERT2 ( null ex_tvs && null eq_spec, ppr dc )        
    map (substTyWith univ_tvs inst_tys) rep_arg_tys
 
@@ -691,7 +693,7 @@ dataConInstOrigArgTys dc@(MkData {dcOrigArgTys = arg_tys,
                                  dcUnivTyVars = univ_tvs, 
                                  dcExTyVars = ex_tvs}) inst_tys
   = ASSERT2( length tyvars == length inst_tys
-          , ptext SLIT("dataConInstOrigArgTys") <+> ppr dc $$ ppr tyvars $$ ppr inst_tys )
+          , ptext (sLit "dataConInstOrigArgTys") <+> ppr dc $$ ppr tyvars $$ ppr inst_tys )
     map (substTyWith tyvars inst_tys) arg_tys
   where
     tyvars = univ_tvs ++ ex_tvs
@@ -706,7 +708,7 @@ dataConInstOrigDictsAndArgTys dc@(MkData {dcOrigArgTys = arg_tys,
                                  dcUnivTyVars = univ_tvs, 
                                  dcExTyVars = ex_tvs}) inst_tys
   = ASSERT2( length tyvars == length inst_tys
-          , ptext SLIT("dataConInstOrigDictsAndArgTys") <+> ppr dc $$ ppr tyvars $$ ppr inst_tys )
+          , ptext (sLit "dataConInstOrigDictsAndArgTys") <+> ppr dc $$ ppr tyvars $$ ppr inst_tys )
     map (substTyWith tyvars inst_tys) (mkPredTys dicts ++ arg_tys)
   where
     tyvars = univ_tvs ++ ex_tvs