More import tidying and fixing the stage 2 build

[ghc-hetmet.git] / compiler / types / TyCon.lhs

diff --git a/compiler/types/TyCon.lhs b/compiler/types/TyCon.lhs
index 51bc1f1..fc27995 100644 (file)
--- a/compiler/types/TyCon.lhs
+++ b/compiler/types/TyCon.lhs
@@ -1,7 +1,9 @@
 %
+% (c) The University of Glasgow 2006
 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
-\section[TyCon]{The @TyCon@ datatype}
+
+The @TyCon@ datatype
 
 \begin{code}
 module TyCon(
@@ -10,7 +12,8 @@ module TyCon(
        PrimRep(..),
        tyConPrimRep,
 
-       AlgTyConRhs(..), visibleDataCons, AlgTyConParent(..),
+       AlgTyConRhs(..), visibleDataCons, 
+        AlgTyConParent(..), hasParent,
        SynTyConRhs(..),
 
        isFunTyCon, isUnLiftedTyCon, isProductTyCon, 
@@ -22,6 +25,7 @@ module TyCon(
        isRecursiveTyCon, newTyConRep, newTyConRhs, newTyConCo_maybe,
        isHiBootTyCon, isSuperKindTyCon,
         isCoercionTyCon_maybe, isCoercionTyCon,
+        isImplicitTyCon,
 
        tcExpandTyCon_maybe, coreExpandTyCon_maybe,
 
@@ -64,13 +68,13 @@ module TyCon(
 import {-# SOURCE #-} TypeRep ( Kind, Type, PredType )
 import {-# SOURCE #-} DataCon ( DataCon, isVanillaDataCon )
 
-import Var             ( TyVar, Id )
-import Class           ( Class )
-import BasicTypes      ( Arity, RecFlag(..), Boxity(..), isBoxed )
-import Name            ( Name, nameUnique, NamedThing(getName) )
-import PrelNames       ( Unique, Uniquable(..) )
-import Maybe           ( isJust )
-import Maybes          ( orElse )
+import Var
+import Class
+import BasicTypes
+import Name
+import PrelNames
+import Maybe
+import Maybes
 import Outputable
 import FastString
 \end{code}
@@ -185,8 +189,10 @@ data TyCon
        tyConUnique :: Unique,
         tyConName   :: Name,
        tyConArity  :: Arity,
-       coKindFun   :: [Type] -> Kind
-    }
+       coKindFun   :: [Type] -> (Type,Type)
+    }          -- INVARAINT: coKindFun is always applied to exactly 'arity' args
+               -- E.g. for trans (c1 :: ta=tb) (c2 :: tb=tc), the coKindFun returns 
+               --      the kind as a pair of types: (ta,tc)
        
   | SuperKindTyCon {    -- Super Kinds, TY (box) and CO (diamond).
                        -- They have no kind; and arity zero
@@ -273,6 +279,10 @@ data AlgTyConParent = -- An ordinary type constructor has no parent.
                                                -- the representation type
                                                -- with the type instance
 
+hasParent :: AlgTyConParent -> Bool
+hasParent NoParentTyCon = False
+hasParent _other        = True
+
 data SynTyConRhs
   = OpenSynTyCon Kind  -- Type family: *result* kind given
   | SynonymTyCon Type   -- Mentioning head type vars.  Acts as a template for
@@ -655,13 +665,21 @@ isSuperKindTyCon :: TyCon -> Bool
 isSuperKindTyCon (SuperKindTyCon {}) = True
 isSuperKindTyCon other               = False
 
-isCoercionTyCon_maybe :: TyCon -> Maybe (Arity, [Type] -> Kind)
+isCoercionTyCon_maybe :: TyCon -> Maybe (Arity, [Type] -> (Type,Type))
 isCoercionTyCon_maybe (CoercionTyCon {tyConArity = ar, coKindFun = rule}) 
   = Just (ar, rule)
 isCoercionTyCon_maybe other = Nothing
 
+isCoercionTyCon :: TyCon -> Bool
 isCoercionTyCon (CoercionTyCon {}) = True
 isCoercionTyCon other              = False
+
+isImplicitTyCon :: TyCon -> Bool
+isImplicitTyCon SynTyCon{}                     = False
+isImplicitTyCon AlgTyCon{algTcParent = parent} = hasParent parent
+isImplicitTyCon other                          = True
+        -- catches: FunTyCon, TupleTyCon, PrimTyCon, 
+        -- CoercionTyCon, SuperKindTyCon
 \end{code}