Using given for a function argument in Scala 3

transaction.scala

// Example from https://www.scala-lang.org/blog/2016/12/07/implicit-function-types.html
import scala.collection.mutable.ListBuffer
import scala.util.chaining.*

class Transaction:
  private val log = ListBuffer[String]()
  private var aborted = false
  private var committed = false

  def println(s: String): Unit =
    log += s

  def abort(): Unit =
    aborted = true

  def isAborted =
    aborted

  def commit(): Unit =
    if !aborted && !committed then
      Console.println("******* log ********")
      log.foreach(Console.println)
      committed = true

object Transaction:
  type Transactional[T] = Transaction ?=> T

  def thisTransaction: Transactional[Transaction] =
    summon[Transaction]

  // literal translation from blog post
  def transaction1[T](op: Transactional[T]) =
    given trans: Transaction = Transaction()
    op
    trans.commit()

  // using Scala 2's implicit
  def transaction2[T](op: Transactional[T]) =
    Transaction().tap(implicit _ => op).commit()

  // using pattern match in Scala 3
  def transaction3[T](op: Transactional[T]) =
    Transaction().tap { case _ @ given Transaction => op }.commit()

  // using ?=>
  def transaction4[T](op: Transactional[T]) =
    Transaction().tap(x => op(using x)).commit()

  // using explicit application, would like to avoid
  def transaction5[T](op: Transactional[T]) =
    Transaction().tap(x => op(using x)).commit()
    Transaction().tap(op(using _)).commit() // would also work with underscore

  extension [A](self: A)
    def contextTap[U](f: A ?=> U): A = 
      f(using self)
      self

  // using custom tap extension
  def transaction6[T](op: Transactional[T]) =
    Transaction().contextTap(op).commit()