parsing functionality as a sequential pipeline using a for comprehension and Option type

case class Event(name: String, start: Int, end: Int)

def validateName(name: String): Option[String] =
  if (name.size > 0) Some(name) else None
 
def validateEnd(end: Int): Option[Int] =
  if (end < 3000) Some(end) else None
 
def validateStart(start: Int, end: Int): Option[Int] =
  if (start <= end) Some(start) else None

def parse(name: String,
          start: Int, end: Int): Option[Event] =
    for {
      validName  <- validateName(name)
      validEnd   <- validateEnd(end)
      validStart <- validateStart(start, end)
    } yield Event(validName, validStart, validEnd)