using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var ns1 = new NormalStruct() { X = 42 };

        var ns2 = ns1;

        Console.WriteLine("Normal structs are reference equal: " + ReferenceEquals(ns1, ns2));

        var rs1 = new ReadonlyStruct() { X = 42 };

        var rs2 = rs1;

        Console.WriteLine("Readonly structs are reference equal: " + ReferenceEquals(rs1, rs2));

        var rsi1 = IAmAnInterface.RSInstance;

        var rsi2 = rsi1;

        Console.WriteLine("Readonly structs accessed through an interface are reference equal: " + ReferenceEquals(rsi1, rsi2));

    }

}

​

public struct NormalStruct

{

    public int X { get; set; }

}

​

public readonly struct ReadonlyStruct : IReadonlyStruct

{

    public int X { get; init; }

}

​

public interface IAmAnInterface

{

    static readonly IReadonlyStruct RSInstance = new ReadonlyStruct() { X = 50 };

}

​

public interface IReadonlyStruct

{

    int X { get; }

}

​