[project @ 2000-09-28 15:15:48 by simonpj]

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

diff --git a/ghc/compiler/types/TyCon.lhs b/ghc/compiler/types/TyCon.lhs
index 9692a9a..b878694 100644 (file)
--- a/ghc/compiler/types/TyCon.lhs
+++ b/ghc/compiler/types/TyCon.lhs
@@ -34,7 +34,7 @@ module TyCon(
        tyConTheta,
        tyConPrimRep,
        tyConArity,
-       tyConClass_maybe,
+       isClassTyCon,
        getSynTyConDefn,
 
         maybeTyConSingleCon,
@@ -110,10 +110,7 @@ data TyCon
        algTyConRec     :: RecFlag,             -- Tells whether the data type is part of 
                                                -- a mutually-recursive group or not
 
-       algTyConClass_maybe :: Maybe Class      -- Nothing for ordinary types; 
-                                               -- Just c for the type constructor
-                                               -- for dictionaries of class c.
-
+       algTyConClass :: Bool           -- True if this tycon comes from a class declaration
     }
 
   | PrimTyCon {                -- Primitive types; cannot be defined in Haskell
@@ -232,7 +229,7 @@ mkAlgTyCon name kind tyvars theta argvrcs cons ncons derivs flavour rec
        dataCons                = cons, 
        noOfDataCons            = ncons,
        algTyConDerivings       = derivs,
-       algTyConClass_maybe     = Nothing,
+       algTyConClass           = False,
        algTyConFlavour         = flavour,
        algTyConRec             = rec
     }
@@ -249,7 +246,7 @@ mkClassTyCon name kind tyvars argvrcs con clas flavour
        dataCons                = [con],
        noOfDataCons            = 1,
        algTyConDerivings       = [],
-       algTyConClass_maybe     = Just clas,
+       algTyConClass           = True,
        algTyConFlavour         = flavour,
        algTyConRec             = NonRecursive
     }
@@ -429,9 +426,9 @@ maybeTyConSingleCon tc = pprPanic "maybeTyConSingleCon: unexpected tycon " $
 \end{code}
 
 \begin{code}
-tyConClass_maybe :: TyCon -> Maybe Class
-tyConClass_maybe (AlgTyCon {algTyConClass_maybe = maybe_cls}) = maybe_cls
-tyConClass_maybe other_tycon                                 = Nothing
+isClassTyCon :: TyCon -> Bool
+isClassTyCon (AlgTyCon {algTyConClass = is_class_tycon}) = is_class_tycon
+isClassTyCon other_tycon                                = False
 \end{code}