Simple scala record

Rec.scala

package record

class Col[T](
    val name: String, 
    private var value: Option[T] = None, 
    private var initialValue: Option[T] = None
  ) {
  
  def apply(v: T): Unit = apply(v, false)
  
  def apply(v: Option[T]): Unit = apply(v, false)
  
  def apply(v: T, init: Boolean): Unit = apply(Option(v), init) 
  
  def apply(v: Option[T], init: Boolean): Unit = {
    val processedValue = processValue(v)
    if(init) {
      initialValue = processedValue
    }
    value = processedValue
  }
  
  def get: Option[T] = value
  
  def dirty = value != initialValue
  
  override def toString = {
    s"Column[name=${name} value=${get} dirty=${dirty}]"
  }
  
  def processValue(v: Option[T]): Option[T] = v
}


class Rec {
  private var cols = Seq[Col[_]]() 
  
  def columns = cols
  
  def col[T](name: String, defaultValue: => Option[T] = None): Col[T] = {
    addColumn[T](createColumn[T](name, defaultValue))
  }
  
  def createColumn[T](name: String, defaultValue: Option[T]): Col[T] ={
    new Col[T](name, defaultValue, None)
  }
    
  def addColumn[T](c: Col[T]): Col[T] = {
    cols = cols :+ c
    c
  }
  
  def dirty = cols.exists(_.dirty)
  
  override def toString = {
    val buf = new scala.collection.mutable.StringBuilder
    buf ++= "{ "
    
    buf ++= cols.view.map { c =>
      s"${c.name}=${c.get.toString}"
    }.mkString(" ")
    
    buf ++= " }"    
    buf.toString
  }
  
  def setOpt[T](c: this.type => Col[T], value: Option[T]): this.type = {
    c(this).apply(value)
    this
  }
  
  def set[T](c: this.type => Col[T], value: T): this.type = {
    c(this).apply(value)
    this
  }
}