1 files changed, 12 insertions, 0 deletions
diff --git a/lib/arel/nodes/unary.rb b/lib/arel/nodes/unary.rb
index edda89e1f0..f679017597 100644
--- a/lib/arel/nodes/unary.rb
+++ b/lib/arel/nodes/unary.rb
@@ -2,10 +2,22 @@ module Arel
   module Nodes
     class Unary < Arel::Nodes::Node
       attr_accessor :expr
+      alias :value :expr
 
       def initialize expr
         @expr = expr
       end
     end
+
+    %w{
+      Not
+      Group
+      Grouping
+      Offset
+      Having
+      On
+    }.each do |name|
+      const_set(name, Class.new(Unary))
+    end
   end
 end