using System;

​

public class Program

{

    public static void Main()

    {

        OptionalValue2<float> myFloat = new();

        myFloat.Value = 4f;

        Console.WriteLine($"myFloat HasValue: {myFloat.HasValue}, Value: {myFloat.Value}"); // HasValue should be true

        myFloat.Value = null;

        Console.WriteLine($"myFloat HasValue: {myFloat.HasValue}, Value: {myFloat.Value}"); // HasValue should be false

        OptionalValue<MyClass> myClass = new();

        myClass.Value = new MyClass();

        Console.WriteLine($"myClass HasValue: {myClass.HasValue}, Value: {myClass.Value}"); // HasValue should be true

        myClass.Value = null;

        Console.WriteLine($"myClass HasValue: {myClass.HasValue}, Value: {myClass.Value}"); // HasValue should be false

    }

}

​

public interface IOptionalValue<T>{

    Type ValueType => typeof(T);

    bool HasValue => Value != null;    

}

​

public class OptionalValue<T> : IOptionalValue<T> where T : class

{   

    public T Value;

}

​

public class OptionalValue2<T> : IOptionalValue<T> where T : struct

{

    public T? Value;

}

​

public class MyClass { }