public TResult Result()
    {
        if (_result is null)
            throw new Exception("Given result type is an error");

        return (TResult) _result;
    }

    public TResult Result()
    {
        if (_result is null)
            throw new Exception("Given result type is an error");

        return (TResult) _result;
    }

public class ParseResult<TResult, TError>
{
    private readonly TResult? _result;
    private readonly TError? _error;

    private ParseResult(TResult? result, TError? error)
    {
        _result = result;
        _error = error;
    }

    public bool IsError() => _error is not null;

    public TResult Result()
    {
        if (_result is null)
            throw new Exception("Given result type is an error");

        return (TResult) _result;
    }

    public static ParseResult<TResult, TError> CreatedResult(TResult result) 
        => new(result, default);

    public static ParseResult<TResult, TError> CreateError(TError error)
        => new(default, error);
}

public class ParseResult<TResult, TError>
{
    private readonly TResult? _result;
    private readonly TError? _error;

    private ParseResult(TResult? result, TError? error)
    {
        _result = result;
        _error = error;
    }

    public bool IsError() => _error is not null;

    public TResult Result()
    {
        if (_result is null)
            throw new Exception("Given result type is an error");

        return (TResult) _result;
    }

    public static ParseResult<TResult, TError> CreatedResult(TResult result) 
        => new(result, default);

    public static ParseResult<TResult, TError> CreateError(TError error)
        => new(default, error);
}