Brainstorming how to localize error messages with scalautil.org's Or and Every.

ParseWithLocalization.scala

package presentation.json

import org.scalautils._
import Accumulation._

case class ErrorMessage(message: String, parameters: Any*) {
  override def toString = message.format(parameters: _*)
}

case class Person(name: String, age: Int)

def parseName(input: String): String Or One[ErrorMessage] = {
  val trimmed = input.trim
  if (!trimmed.isEmpty)
    Good(trimmed)
  else
    Bad(One(ErrorMessage(""""%s" is not a valid name""", input)))
}

def parseAge(input: String): Int Or One[ErrorMessage] = {
  try {
    val age = input.trim.toInt
    if (age >= 0) Good(age) else Bad(One(ErrorMessage(""""%s" is not a valid age""", age)))
  }
  catch {
    case _: NumberFormatException =>
      Bad(One(ErrorMessage(""""%s" is not a valid integer""", input)))
  }
}

def parsePerson(inputName: String,
      inputAge: String): Person Or Every[ErrorMessage] = {

  val name = parseName(inputName)
  val age = parseAge(inputAge)
  withGood(name, age) { Person(_, _) }
}