simple utility tool that reads two files and outputs their difference

FilesDiff.scala

import java.io.PrintWriter

import cats.effect.{ExitCode, IO, IOApp, Resource, Sync}
import cats.syntax.traverse._
import cats.syntax.functor._

import scala.io.Source

object IdDiff extends IOApp {

  def readFromFile[F[_]: Sync](name: String): F[List[String]] = Resource
    .fromAutoCloseable(
      Sync[F].delay(Source.fromFile(name))
    )
    .use(source => Sync[F].delay(source.getLines.toList))

  def writeToFile[F[_]: Sync](name: String, lines: List[String]): F[Unit] = {
    Resource.fromAutoCloseable(
      Sync[F].delay(new PrintWriter(name))
    )
      .use(pw =>
        lines.traverse(line => Sync[F].delay(pw.println(line)))
      ).void

  }

  override def run(args: List[String]): IO[ExitCode] = for {
    lines1  <- readFromFile[IO](name = "???")
    lines2 <- readFromFile[IO](name = "???")
    diff = lines1.diff(lines2)
    _ = println(s"first file has:${lines1.size} and second one has:${lines2.size}. The two had a diff of ${diff.size} lines.")
    _ <- writeToFile[IO](name = "???", diff)
  } yield ExitCode.Success
}