public void CheckIsOfType02()
        {
            object param = null;

            UseCaseTestHelper.Test(() =>
            {
                // Use Case: this is what the use would write without conditions.
                if (!(param is string))
                {
                    if (param == null)
                    {
                        throw new ArgumentNullException("param", "param should not be of type string.");
                    }
                    else
                    {
                        throw new ArgumentException("param should not be of type string.", "param");
                    }
                }
            },
                                   () =>
            {
                // This is what the user should write with conditions.
                Condition.Requires(param, "param").IsOfType(typeof(string));
            });
        }
        public void CheckIsNull01()
        {
            object param = new object();

            UseCaseTestHelper.Test(() =>
            {
                // Use Case: this is what the user would write without conditions.
                if (param != null)
                {
                    throw new ArgumentException("param should not be null.", "param");
                }
            },
                                   () =>
            {
                // This is what the user should write with conditions.
                Condition.Requires(param, "param").IsNull();
            });
        }