Fix scoped type variables for expression type signatures

[ghc-hetmet.git] / compiler / hsSyn / HsBinds.lhs

diff --git a/compiler/hsSyn/HsBinds.lhs b/compiler/hsSyn/HsBinds.lhs
index 40b51ca..0588047 100644 (file)
--- a/compiler/hsSyn/HsBinds.lhs
+++ b/compiler/hsSyn/HsBinds.lhs
@@ -76,7 +76,7 @@ data HsBind id
 
        fun_matches :: MatchGroup id,   -- The payload
 
-       fun_co_fn :: ExprCoFn,  -- Coercion from the type of the MatchGroup to the type of
+       fun_co_fn :: HsWrapper, -- Coercion from the type of the MatchGroup to the type of
                                -- the Id.  Example:
                                --      f :: Int -> forall a. a -> a
                                --      f x y = y
@@ -84,9 +84,7 @@ data HsBind id
                                -- (with a free type variable a').  The coercion will take
                                -- a CoreExpr of this type and convert it to a CoreExpr of
                                -- type         Int -> forall a'. a' -> a'
-                               -- Notice that the coercion captures the free a'.  That's
-                               -- why coercions are (CoreExpr -> CoreExpr), rather than
-                               -- just CoreExpr (with a functional type)
+                               -- Notice that the coercion captures the free a'.
 
        bind_fvs :: NameSet     -- After the renamer, this contains a superset of the 
                                -- Names of the other binders in this binding group that 
@@ -298,67 +296,67 @@ instance (OutputableBndr id) => Outputable (IPBind id) where
 %************************************************************************
 
 \begin{code}
--- A ExprCoFn is an expression with a hole in it
+-- A HsWrapper is an expression with a hole in it
 -- We need coercions to have concrete form so that we can zonk them
 
-data ExprCoFn
-  = CoHole                     -- The identity coercion
+data HsWrapper
+  = WpHole                     -- The identity coercion
 
-  | CoCompose ExprCoFn ExprCoFn        -- (\a1..an. []) `CoCompose` (\x1..xn. [])
+  | WpCompose HsWrapper HsWrapper      -- (\a1..an. []) `WpCompose` (\x1..xn. [])
                                --      = (\a1..an \x1..xn. [])
 
-  | ExprCoFn Coercion          -- A cast:  [] `cast` co
+  | WpCo Coercion              -- A cast:  [] `cast` co
                                -- Guaranteedn not the identity coercion
 
-  | CoApp Var                  -- [] x; the xi are dicts or coercions
-  | CoTyApp Type               -- [] t
-  | CoLam Id                   -- \x. []; the xi are dicts or coercions
-  | CoTyLam TyVar              -- \a. []
+  | WpApp Var                  -- [] x; the xi are dicts or coercions
+  | WpTyApp Type               -- [] t
+  | WpLam Id                   -- \x. []; the xi are dicts or coercions
+  | WpTyLam TyVar              -- \a. []
 
        -- Non-empty bindings, so that the identity coercion
-       -- is always exactly CoHole
-  | CoLet (LHsBinds Id)                -- let binds in []
+       -- is always exactly WpHole
+  | WpLet (LHsBinds Id)                -- let binds in []
                                -- (would be nicer to be core bindings)
 
-instance Outputable ExprCoFn where 
-  ppr co_fn = pprCoFn (ptext SLIT("<>")) co_fn
+instance Outputable HsWrapper where 
+  ppr co_fn = pprHsWrapper (ptext SLIT("<>")) co_fn
 
-pprCoFn :: SDoc -> ExprCoFn -> SDoc
-pprCoFn it CoHole = it
-pprCoFn it (CoCompose f1 f2) = pprCoFn (pprCoFn it f2) f1
-pprCoFn it (ExprCoFn co)     = it <+> ptext SLIT("`cast`") <+> pprParendType co
-pprCoFn it (CoApp id)    = it <+> ppr id
-pprCoFn it (CoTyApp ty)  = it <+> ptext SLIT("@") <+> pprParendType ty
-pprCoFn it (CoLam id)    = ptext SLIT("\\") <> pprBndr LambdaBind id <> dot <+> it
-pprCoFn it (CoTyLam tv)  = ptext SLIT("/\\") <> pprBndr LambdaBind tv <> dot <+> it
-pprCoFn it (CoLet binds) = sep [ptext SLIT("let") <+> braces (ppr binds), it]
+pprHsWrapper :: SDoc -> HsWrapper -> SDoc
+pprHsWrapper it WpHole = it
+pprHsWrapper it (WpCompose f1 f2) = pprHsWrapper (pprHsWrapper it f2) f1
+pprHsWrapper it (WpCo co)     = it <+> ptext SLIT("`cast`") <+> pprParendType co
+pprHsWrapper it (WpApp id)    = it <+> ppr id
+pprHsWrapper it (WpTyApp ty)  = it <+> ptext SLIT("@") <+> pprParendType ty
+pprHsWrapper it (WpLam id)    = ptext SLIT("\\") <> pprBndr LambdaBind id <> dot <+> it
+pprHsWrapper it (WpTyLam tv)  = ptext SLIT("/\\") <> pprBndr LambdaBind tv <> dot <+> it
+pprHsWrapper it (WpLet binds) = sep [ptext SLIT("let") <+> braces (ppr binds), it]
 
-(<.>) :: ExprCoFn -> ExprCoFn -> ExprCoFn
-CoHole <.> c = c
-c <.> CoHole = c
-c1 <.> c2    = c1 `CoCompose` c2
+(<.>) :: HsWrapper -> HsWrapper -> HsWrapper
+WpHole <.> c = c
+c <.> WpHole = c
+c1 <.> c2    = c1 `WpCompose` c2
 
-mkCoTyApps :: [Type] -> ExprCoFn
-mkCoTyApps tys = mk_co_fn CoTyApp (reverse tys)
+mkWpTyApps :: [Type] -> HsWrapper
+mkWpTyApps tys = mk_co_fn WpTyApp (reverse tys)
 
-mkCoApps :: [Id] -> ExprCoFn
-mkCoApps ids = mk_co_fn CoApp (reverse ids)
+mkWpApps :: [Id] -> HsWrapper
+mkWpApps ids = mk_co_fn WpApp (reverse ids)
 
-mkCoTyLams :: [TyVar] -> ExprCoFn
-mkCoTyLams ids = mk_co_fn CoTyLam ids
+mkWpTyLams :: [TyVar] -> HsWrapper
+mkWpTyLams ids = mk_co_fn WpTyLam ids
 
-mkCoLams :: [Id] -> ExprCoFn
-mkCoLams ids = mk_co_fn CoLam ids
+mkWpLams :: [Id] -> HsWrapper
+mkWpLams ids = mk_co_fn WpLam ids
 
-mk_co_fn :: (a -> ExprCoFn) -> [a] -> ExprCoFn
-mk_co_fn f as = foldr (CoCompose . f) CoHole as
+mk_co_fn :: (a -> HsWrapper) -> [a] -> HsWrapper
+mk_co_fn f as = foldr (WpCompose . f) WpHole as
 
-idCoercion :: ExprCoFn
-idCoercion = CoHole
+idHsWrapper :: HsWrapper
+idHsWrapper = WpHole
 
-isIdCoercion :: ExprCoFn -> Bool
-isIdCoercion CoHole = True
-isIdCoercion other  = False
+isIdHsWrapper :: HsWrapper -> Bool
+isIdHsWrapper WpHole = True
+isIdHsWrapper other  = False
 \end{code}