1 files changed, 19 insertions, 20 deletions

diff --git a/lib/arel/engines/memory/predicates.rb b/lib/arel/engines/memory/predicates.rb
index c0ee862626..0e88810e7d 100644
--- a/lib/arel/engines/memory/predicates.rb
+++ b/lib/arel/engines/memory/predicates.rb
@@ -13,41 +13,40 @@ module Arel
     end
     
     class Not < Unary
-      def operator; '!' end
-    end
-    
-    class CompoundPredicate < Binary
       def eval(row)
-        eval "operand1.eval(row) #{operator} operand2.eval(row)"
+        !operand.eval(row)
       end
     end
-
-    class Or < CompoundPredicate
-      def operator; :or end
-    end
-
-    class And < CompoundPredicate
-      def operator; :and end
-    end
     
-    class GroupedPredicate < Polyadic
+    class Polyadic < Predicate
       def eval(row)
-        group = additional_operands.inject([]) do |results, operand|
-          results << operator.new(operand1, operand)
-        end
-        group.send(compounder) do |operation|
+        predicates.send(compounder) do |operation|
           operation.eval(row)
         end
       end
     end
     
-    class Any < GroupedPredicate
+    class Any < Polyadic
       def compounder; :any? end
     end
     
-    class All < GroupedPredicate
+    class All < Polyadic
       def compounder; :all? end
     end
+    
+    class CompoundPredicate < Binary
+      def eval(row)
+        eval "operand1.eval(row) #{operator} operand2.eval(row)"
+      end
+    end
+
+    class Or < CompoundPredicate
+      def operator; :or end
+    end
+
+    class And < CompoundPredicate
+      def operator; :and end
+    end
 
     class Equality < Binary
       def operator; :== end