I have done the following code (down) as a new project on VS2022 with .NET7 (and C# 11).
The call at the end to "AllFlagsViaBitwise" give me an error:
Error 1 CS0315 The type 'ConsoleAppTestEnumAll.Program.Options' cannot be used as type parameter 'TSelf' in the generic type or method 'IBitwiseOperators<TSelf, TOther, TResult>'. There is no boxing conversion from 'ConsoleAppTestEnumAll.Program.Options' to 'System.Numerics.IBitwiseOperators<ConsoleAppTestEnumAll.Program.Options, int, ConsoleAppTestEnumAll.Program.Options>'. ConsoleAppTestEnumAll C:\prj\Personnel\ConsoleAppTestEnumAll\ConsoleAppTestEnumAll\Program.cs 10 Active
According to "Petrusion" on its answer to another of my question on StackOverflow question How to generically combine all bits (I mean OR all values) of a [FLAGS] enum, having only valid values (bits) declared in the resulting enum?... The code should works. The code works for him.
The code should compile and work as is but I have CS0315, why?
Note: It is part of a new features that come with C# 11 (.Net 7), as far as what I understand.
using System.Diagnostics;
using System.Numerics;
using System.Runtime.CompilerServices;
namespace ConsoleAppTestEnumAll
{
internal class Program
{
[Flags]
public enum Options
{
Opt1 = 1,
Opt2 = 2,
Opt4= 4,
}
public class EnumUtil
{
public static T AllFlagsViaBitwise<T>() where T : unmanaged, Enum, IBitwiseOperators<T, T, T>, IEqualityOperators<T, T, bool>
{
T result = default;
foreach (var value in Enum.GetValues<T>())
{
if ((result & value) != default)
{
throw new ArgumentException(
$"{typeof(T).Name} is not a flags enum. Detected at enum value {value}", nameof(T));
}
result |= value;
}
return result;
}
}
static void Main(string[] args)
{
Debug.Assert(EnumUtil.AllFlagsViaBitwise<Options>() == 7);
}
}
}
Project configuration 1/2
Project configuration 2/2
