Http4s and scala-cli

Main.scala

//> using scala "3.1"
//> using lib "org.http4s::http4s-dsl:0.23.12"
//> using lib "org.http4s::http4s-ember-server:0.23.12"
//> using lib "org.http4s::http4s-ember-client:0.23.12"

import cats.effect._
import org.http4s._
import org.http4s.dsl.io._
import org.http4s.ember.server.EmberServerBuilder
import org.http4s.server.Router
import com.comcast.ip4s.{host, port}

object HelloApp extends IOApp:

  def helloRoutes = HttpRoutes.of[IO] {
      case GET -> Root                  => Ok("Hello World!")
      case GET -> Root / "hello" / name => Ok(s"Hello, $name!")
    }
    .orNotFound

  def run(args: List[String]): IO[ExitCode] =
    val host = host"0.0.0.0"
    val port = port"8080"
    EmberServerBuilder
      .default[IO]
      .withHost(host)
      .withPort(port)
      .withHttpApp(helloRoutes)
      .build
      .use(_ => IO.never)
      .as(ExitCode.Success)