added a greater than node

lib/arel/attributes/attribute.rb

@@ -28,6 +28,10 @@ module Arel
       def gteq right
         Nodes::GreaterThanOrEqual.new self, right
       end
+
+      def gt right
+        Nodes::GreaterThan.new self, right
+      end
     end
 
     class String  < Attribute; end

lib/arel/nodes.rb

@@ -2,6 +2,7 @@ require 'arel/nodes/binary'
 require 'arel/nodes/equality'
 require 'arel/nodes/or'
 require 'arel/nodes/and'
+require 'arel/nodes/greater_than'
 require 'arel/nodes/greater_than_or_equal'
 
 require 'arel/nodes/in'

lib/arel/nodes/greater_than.rb

@@ -0,0 +1,6 @@
+module Arel
+  module Nodes
+    class GreaterThan < Arel::Nodes::Binary
+    end
+  end
+end

lib/arel/visitors/to_sql.rb

@@ -113,6 +113,10 @@ module Arel
         "#{visit o.left} >= #{visit o.right}"
       end
 
+      def visit_Arel_Nodes_GreaterThan o
+        "#{visit o.left} > #{visit o.right}"
+      end
+
       def visit_Arel_Nodes_StringJoin o
         "#{visit o.left} #{visit o.right}"
       end

spec/arel/attributes/attribute_spec.rb

@@ -3,6 +3,22 @@ require 'spec_helper'
 module Arel
   module Attributes
     describe 'attribute' do
+      describe '#gt' do
+        it 'should create a GreaterThan node' do
+          relation = Table.new(:users)
+          relation[:id].gt(10).should be_kind_of Nodes::GreaterThan
+        end
+
+        it 'should generate >= in sql' do
+          relation = Table.new(:users)
+          mgr = relation.project relation[:id]
+          mgr.where relation[:id].gt(10)
+          mgr.to_sql.should be_like %{
+            SELECT "users"."id" FROM "users" WHERE "users"."id" > 10
+          }
+        end
+      end
+
       describe '#gteq' do
         it 'should create a GreaterThanOrEqual node' do
           relation = Table.new(:users)