scala-pimps

This is simple scala library that provides some frequent routines often used by my codes.

The uMap (unboxed map)

uMap works as standard List.map(f: A => B)'s function. Difference is that you don't need a value to be wrapped into container. It works on pure value. def uMap[A](f: A => B): B takes value and applies function f on it returning it's result.

  //Let's say this is our simple test model.
  //
  case class A[T](t: T)
  case class B[T](t: T)
  case class C[T1, T2](t1: T1, t2: T2)

  //ugly syntax,
  //read the code and realize that you recursively trying to remember that you are inside C then inside B then inside A and the first param of A when constructing it is "http://panasoft.pl/" and we must uppercase that param and then in ...
  //... Damn, where was I?
  //
  val b = C(B(A("http://panasoft.pl".toUpperCase())), ":)")

  //nicer syntax using uMap
  val a = "http://panasoft.pl"  // have some string
    .uMap(_.toUpperCase)        // I want to uppercase it
    .uMap(A(_))                 // then result of previous instruction I'm applying to create A, now I have A(...)
    .uMap(B(_))                 // then result of previous instruction I'm applying to create B, now I have B(...)
    .uMap(C(_, ":)"))           // then result of previous instruction I'm applying to create C, now I have C(..., ":)")

The andThen or its alias andThenPerform

andThen is used to join executions. Result of andThen is the last instruction in chain. Some times you don't need to use { and } - use andThen to join executions.

  //before
  def myRoutine = {
    logger.debug("start of method a")
    sendEmail
    postEvent(...)
    copySomeFiles
    2 + 2
  }

  //using andThen(...)
  def myRoutine = logger.debug("start of method a")
    .andThenPerform(sendEmail)
    .andThenPerform(postEvent(...))
    .andThenPerform(copySomeFiles)
    .andThenPerform(2 + 2)

The modify

modify performs side effects and results in contexed value.

    //standard approach
    def createAndSetupJB(x:Any): JavaBean = {
      val jb = new JavaBean()
      jb.x = x
      jb.y = "Y"
      jb.z = "Z"
      jb
    }

    //nicer syntax
    def createAndSetupJB2(x:Any): JavaBean =
      (new JavaBean()).
      .modify(_.x = x)
      .modify(_.y = "Y")
      .modify(_.z = "Z")