I’m trying to add a boolean flag option to my System.CommandLine C#/.NET program. However, nothing I specify when I run the program seems to result in a true value in my command handler:

using System.CommandLine;
using System.CommandLine.Parsing;
using System.CommandLine.Builder;
using System.CommandLine.NamingConventionBinder;

var rootCommand = new RootCommand
{
  Description = "System.CommandLine Example"
};

var exampleOption = new Option<bool>(
  new[] { "--opt", "-o" },
  "Set an example boolean option to true"
);

var exampleCommand = new Command("command", "Example command")
{
  Handler = CommandHandler.Create<bool>((flag) =>
  {
    Console.WriteLine($"Ran example command with opt={flag}");
  })
};


exampleCommand.AddOption(exampleOption);
rootCommand.AddCommand(exampleCommand);

var parser = new CommandLineBuilder(rootCommand)
  .UseHelp()
  .UseDefaults()
  .Build();

await parser.InvokeAsync(args);

When I invoke it, I get this result:

SystemCommandLineExample.exe command --opt=true
Ran example command with opt=False

What am I doing wrong?