Remove the distinction between data and newtype families

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

diff --git a/compiler/hsSyn/HsDecls.lhs b/compiler/hsSyn/HsDecls.lhs
index 1822b58..37ab35a 100644 (file)
--- a/compiler/hsSyn/HsDecls.lhs
+++ b/compiler/hsSyn/HsDecls.lhs
@@ -358,7 +358,7 @@ Interface file code:
 --
 --   * If it is 'Just pats', we have the definition of an indexed type.  Then,
 --     'pats' are type patterns for the type-indexes of the type constructor
---     and 'tcdVars' are the variables in those patterns.  Hence, the arity of
+--     and 'tcdTyVars' are the variables in those patterns.  Hence, the arity of
 --     the indexed type (ie, the number of indexes) is 'length tcdTyPats' and
 --     *not* 'length tcdVars'.
 --
@@ -373,12 +373,16 @@ data TyClDecl name
                tcdFoType   :: FoType
     }
 
+       -- type/data/newtype family T :: *->*
   | TyFamily {  tcdFlavour:: FamilyFlavour,            -- type, new, or data
                tcdLName  :: Located name,              -- type constructor
                tcdTyVars :: [LHsTyVarBndr name],       -- type variables
                tcdKind   :: Maybe Kind                 -- result kind
     }
 
+       -- Declares a data type or newtype, giving its construcors
+       --      data/newtype T a = <constrs>
+       --      data/newtype instance T [a] = <constrs>
   | TyData {   tcdND     :: NewOrData,
                tcdCtxt   :: LHsContext name,           -- Context
                tcdLName  :: Located name,              -- Type constructor
@@ -406,9 +410,6 @@ data TyClDecl name
                        -- Typically the foralls and ty args are empty, but they
                        -- are non-empty for the newtype-deriving case
     }
-       -- data instance: tcdPats = Just tys
-       --
-       -- data:          tcdPats = Nothing, 
 
   | TySynonym {        tcdLName  :: Located name,              -- type constructor
                tcdTyVars :: [LHsTyVarBndr name],       -- type variables
@@ -439,7 +440,7 @@ data NewOrData
 
 data FamilyFlavour
   = TypeFamily                 -- "type family ..."
-  | DataFamily NewOrData       -- "newtype family ..." or "data family ..."
+  | DataFamily                 -- "data family ..."
 \end{code}
 
 Simple classifiers
@@ -535,9 +536,8 @@ instance OutputableBndr name
       = pp_flavour <+> pp_decl_head [] ltycon tyvars Nothing <+> pp_kind
         where
          pp_flavour = case flavour of
-                        TypeFamily          -> ptext SLIT("type family")
-                        DataFamily NewType  -> ptext SLIT("newtype family")
-                        DataFamily DataType -> ptext SLIT("data family")
+                        TypeFamily -> ptext SLIT("type family")
+                        DataFamily -> ptext SLIT("data family")
 
           pp_kind = case mb_kind of
                      Nothing   -> empty