Consider custom parsers/converters/handler for types?

I would love to be able to do:

```c#
public class Options
{
[Option('o', "out", Required = true, HelpText = "Output file")]
public string OutFile { get; set; }
[Option('d', "duration", Required = false, Default = "1:00:00", HelpText = "Duration")]
public TimeSpan Duration { get; set; }
[Option('e', "endpoint", Required = true, HelpText = "IP Endpoint (:)")]
public IPEndPoint Endpoint { get; set; }
}
```

Where I can use types like `TimeSpan` and `IPEndPoint` or any other type. Ofcourse, we would need to be able to specify a parser/converter/handler/whatever that takes the value and converts it to the desired type. I imagine it be like:

```c#
public class Options
{
[Option('o', "out", Required = true, HelpText = "Output file")]
public string OutFile { get; set; }
[Option('d', "duration", Required = false, Default = "1:00:00", HelpText = "Duration", Converter = typeof(MyTimeSpanConverter))]
public TimeSpan Duration { get; set; }
[Option('e', "endpoint", Required = true, HelpText = "IP Endpoint (:)", Converter = typeof(MyIPEndpointConverter))]
public IPEndPoint Endpoint { get; set; }
}
```

Next these 'converters' should implement something like an IConvert that defines a method `T Convert(string value)` where they take a string (the commandline argument) and convert to the desired type. Another option would be to not use the attributes but be able to specify handlers like:

```c#
Parser.Default
.Register()
.Register()
.ParseArguments(args)
....
```

Would that be something that you would consider? (Maybe not exactly following the idea given above, but the broader idea of being able to handle custom types).

Aucun fichier d’implémentation ni test n’est indiqué. Commencez par Parser.Default et ParseArguments, suivez ensuite la manière dont les chaînes d’options sont converties actuellement et comparez les approches proposées, basées sur des attributs, pour Converter et l’enregistrement. Le travail est considéré comme terminé lorsque des types personnalisés tels que TimeSpan et IPEndPoint peuvent être pris en charge via une API définie et testée.

Rédigé par le modèle d'indexation à partir du texte de l'issue.