コレクション初期化子のoverload解決順

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;

namespace ConsoleApplication1
{
  class MyCollection : IEnumerable
  {
    public void Add(object value)
    {
      Console.WriteLine("Call object overload");
    }
    public void Add(int value)
    {
      Console.WriteLine("Call int overload");
    }
    public void Add(string value)
    {
      Console.WriteLine("Call string overload");
    }

    public IEnumerator GetEnumerator()
    {
      throw new NotImplementedException();
    }
  }
  class Program
  {
    static void Main(string[] args)
    {
      var col = new MyCollection { "1", 1, null, (object)null };

      // 実行結果
      // Call string overload
      // Call int overload
      // Call string overload
      // Call object overload
    }
  }
}