Spectre.Console composed CLI

Program.cs

using System.ComponentModel;
using Spectre.Console;
using Spectre.Console.Cli;

using Console = Spectre.Console.AnsiConsole;

CommandApp app = new();

app.Configure(configuration =>
{
    configuration.UseAssemblyInformationalVersion();

    configuration.AddCommand<HelloCommand>("hello")
        .WithDescription("Greets the user with a hello message.");

    configuration.AddCommand<GoodbyeCommand>("goodbye")
        .WithDescription("Greets the user with a goodbye message.");
});

return await app.RunAsync(args);

internal abstract class GreetCommandSettings : CommandSettings
{
    [CommandOption("-n|--name")]
    [Description("The name of the person to greet. Defaults to 'World'.")]
    [DefaultValue("World")]
    public string? Name { get; set; }
}

internal sealed class HelloCommandSettings : GreetCommandSettings;

internal sealed class GoodbyeCommandSettings : GreetCommandSettings;

internal sealed class HelloCommand : Command<HelloCommandSettings>
{
    public override int Execute(CommandContext context, HelloCommandSettings settings)
        => context.ProcessGreeting("Hello", settings);
}

internal sealed class GoodbyeCommand : Command<GoodbyeCommandSettings>
{
    public override int Execute(CommandContext context, GoodbyeCommandSettings settings)
        => context.ProcessGreeting("Goodbye", settings);
}

internal static class GreetCommandExtensions
{
    public static int ProcessGreeting(this CommandContext _, string salutation, GreetCommandSettings settings)
    {
        string greeting = $"{salutation}, {settings.Name}!";

        Panel panel = new Panel($"[blue bold]{greeting}[/]")
            .Border(BoxBorder.Rounded)
            .BorderColor(Color.Green)
            .Header("[red italic]Greeting[/]")
            .Padding(2, 4)
            .Expand();

        Console.Write(panel);

        return 0;
    }
}

project.csproj

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net10.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Spectre.Console" Version="0.50.0" />
    <PackageReference Include="Spectre.Console.Cli" Version="0.50.0" />
  </ItemGroup>
</Project>

solution.slnx

<Solution>
  <Project Path="project.csproj" />
</Solution>