X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FbasicTypes%2FDataCon.lhs;h=844c69b5551b8f937c384becf11c259bb9ab6f90;hb=9f703fe41b8300777dc8fcd8da94a3a082fdcfbb;hp=0c6e3c57200d8f94c9e6d1691100b38af8875de3;hpb=6a05ec5ef5373f61b7f9f5bdc344483417fa801b;p=ghc-hetmet.git

diff --git a/compiler/basicTypes/DataCon.lhs b/compiler/basicTypes/DataCon.lhs
index 0c6e3c5..844c69b 100644
--- a/compiler/basicTypes/DataCon.lhs
+++ b/compiler/basicTypes/DataCon.lhs
@@ -275,7 +275,7 @@ data DataCon
 	-- Reason: less confusing, and easier to generate IfaceSyn
 
 	dcEqSpec :: [(TyVar,Type)],	-- Equalities derived from the result type, 
-					-- *as written by the programmer*
+					-- /as written by the programmer/
 		-- This field allows us to move conveniently between the two ways
 		-- of representing a GADT constructor's type:
 		--	MkT :: forall a b. (a :=: [b]) => b -> T a
@@ -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