using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var results = new IResult[]

        {

            SuccessResult.Instance,

            new SuccessResult<int>( 1 ),

            FailureResult.Instance,

            new FailureResult<int>( new[] { -1 } ),

        };

        foreach( var result in results )

        {

            var msg = result switch

            {

                SuccessResult<int> sri => $"Successful with data {sri.Data}",

                SuccessResult sr => $"Successful with no data",

                FailureResult<int> fri => $"Failed with errors",

                FailureResult fr => $"Failed without errors",

                _ => throw new NotImplementedException( result.GetType().FullName ),

            };

            Console.WriteLine( msg );

        }

    }

}

​

​

public interface IResult

{

}

​

public record SuccessResult : IResult

{

    public static readonly SuccessResult Instance = new();

}

​

public record SuccessResult<TData>( TData Data ) : SuccessResult;

​

public record FailureResult : IResult

{

    public static readonly FailureResult Instance = new();

}

​

public record FailureResult<TError>( IEnumerable<TError> Errors ) : FailureResult;