[project @ 2003-08-20 15:07:56 by simonmar]

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

diff --git a/ghc/compiler/types/Class.lhs b/ghc/compiler/types/Class.lhs
index 6181d4f..3a37d16 100644 (file)
--- a/ghc/compiler/types/Class.lhs
+++ b/ghc/compiler/types/Class.lhs
@@ -24,6 +24,7 @@ import Name           ( NamedThing(..), Name )
 import BasicTypes      ( Arity )
 import Unique          ( Unique, Uniquable(..) )
 import Outputable
+import Util             ( notNull )
 \end{code}
 
 %************************************************************************
@@ -62,6 +63,7 @@ type ClassOpItem = (Id, DefMeth Name)
 
 data DefMeth id = NoDefMeth            -- No default method
                | DefMeth id            -- A polymorphic default method (named id)
+                                       --      (Only instantiated to RdrName and Name, never Id)
                | GenDefMeth            -- A generic default method
                 deriving Eq  
 \end{code}
@@ -116,7 +118,7 @@ classExtraBigSig (Class {classTyVars = tyvars, classFunDeps = fundeps,
   = (tyvars, fundeps, sc_theta, sc_sels, op_stuff)
 
 classHasFDs :: Class -> Bool
-classHasFDs (Class {classFunDeps = fundeps}) = not (null fundeps)
+classHasFDs (Class {classFunDeps = fundeps}) = notNull fundeps
 \end{code}