gistfile1.cs

public struct NotNull<T> where T : class
{
    private readonly T _Value;

    private NotNull(T value)
    {
        if (value == null)
            throw new ArgumentNullException("value");

        _Value = value;
    }

    public static explicit operator NotNull<T>(T value)
    {
        return new NotNull<T>(value);
    }

    public static explicit operator T(NotNull<T> value)
    {
        return value._Value;
    }

    public static bool operator ==(NotNull<T> obj1, NotNull<T> obj2)
    {
        return obj1.Equals(obj2);
    }

    public static bool operator !=(NotNull<T> obj1, NotNull<T> obj2)
    {
        return !(obj1 == obj2);
    }

    public override bool Equals(object obj)
    {
        if(obj is NotNull<T>)
            return Equals((NotNull<T>)obj);

        return _Value.Equals(obj);
    }

    public bool Equals(NotNull<T> other)
    {
        return Equals(other._Value, _Value);
    }

    public override int GetHashCode()
    {
        return _Value.GetHashCode();
    }

    public override string ToString()
    {
        return _Value.ToString();
    }
}