Collections Data Structure C#

//The MIT License (MIT)
//http://arolibraries.codeplex.com/license
using System;
using System.Collections;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading;
namespace AroLibraries.ExtensionMethods.Enumerable
{
    public static class IEnumerableExt
    {
        public static T Ext_Aggregate(this IEnumerable list, Func aggregateFunction)
        {
            return Ext_Aggregate(list, default(T), aggregateFunction);
        }
        public static T Ext_Aggregate(this IEnumerable list, T defaultValue, Func aggregateFunction)
        {
            return list.Count() <= 0 ?
                defaultValue : list.Aggregate(aggregateFunction);
        }
   }
}