Monadic json parser descriptor

json-parser.scala

{
object Parser {
  def apply(name: String): Parser = Parser(name, Nil)
}

case class Parser(name: String, items: List[Parser]) {
//  println("parser constructor: " + this)

  def flatMap(parser: Parser => Parser): Parser = { 
    println("flatMap: " + this)
    val x = parser(this)
    println("flatMap: " + this + ", parser(this)" + x)
    val y = Parser(name, items ::: x.items)
    println("flatMap: " + this + ", returns " + y)
    y   
  }

  def map(parser: Parser => Parser): Parser = { 
    println("map: " + this)
    val x = parser(this)
    println("map: " + this + ", parser(this)=" + x)
    val y = Parser(name, items ::: x.items)
    println("map: " + this + ", returns " + y)
    y   
  }
}

case class Person(name: String, address: String)

val p = for {
  name: Parser <- Parser("name")
  age: Parser <- Parser("age")
  address: Parser <- Parser("address")
} yield {
  println("yield")
  Parser("boo", List(name, age, address))
}

println("parser=" + p)
}