using System;
using System.Collections.Generic;

public class Test[T]
{
  protected  mutable  item : T;

  public this (mutable  item : T)
  {
    this.item = item;
  }

  public GetEnumerator() :  IEnumerator[T]
  {
    yield item;
  }
}

class X
{
  static Main () :  void
  {
    mutable  test =  Test (3);
    foreach ( a in test)
      Console.WriteLine(a);
  }
}

/*
BEGIN-OUTPUT
3
END-OUTPUT
*/