How to add constraints to an int option?

[loudenvier]

Is it possible to set constraints to an int option so that it have min and max allowed values? I think that's a pretty common scenario, but the following fails:

[Option('q', "quality", Default = 80, Min = 1, Max = 100)]
public int Quality { get; set; }    

With this exception: System.InvalidOperationException: Scalar option specifications do not support range specification.

If the library does not provide this functionality how would I implement it on my own and still play nicely with the auto help and error messages that the library automatically outputs on invalid input?

[ShadowXPA]

As per the wiki, the Min and Max only apply to IEnumerable.

I agree, it's a pretty common scenario, and I tried doing the same you did.
My work around is validating the options manually, and displaying an error message, along with the help text. It would be nice to have an option to add errors to the list of errors though, so it shows in the help text.

I have this Extension method:

public static HelpText AddErrors(this HelpText helpText, IEnumerable<string> errors)
{
    helpText.AddPreOptionsLine("\nERROR(S):"); // Simulating the ERROR(S)'s header
    helpText.AddPreOptionsLines(errors); // You might want to format your errors by prefixing with 2 spaces to match the original
    return helpText;
}

Something like this would be nicer:

var helpText = HelpText.AutoBuild(parserResult);
helpText.AddErrorLine("Quality needs to be between 1 and 100.");
// helpText.AddErrorLines(["", "", ...]);
// helpText.AddErrorText("");
Console.WriteLine(helpText);