On this page, we'll allow the user to select a series of <div> tags to display based on the results of a form submission.

<div> number visible

This is div 0

This is div 1

This is div 2

This is div 3

This is div 4

This is div 5

The code to store the state of the div tags is:

private var whichDivs: Array[Boolean] = Array(true, true, true, true, true, true)

And to select the div tags:

  def selectDivs(in: NodeSeq): NodeSeq = {
    def calcNum(in: String): Box[Int] = 
      if (in.startsWith("num_")) asInt(in.substring(4))
      else Empty

    for {
      div <- in \\ "div" // select the div tags
      id = (div \ "@id").text // get their id
      num <- calcNum(id) if whichDivs(num) // filter 
    } yield div
  }