Check if a given code is a consistent with the ISIN standard

Isin.scala

package isin

object Isin {
  
  // based on http://en.wikipedia.org/wiki/International_Securities_Identification_Number
  def isIsin(code: String): Boolean = {
    val digits: String = code.init.map(c => BigInt(c.toString, 36)).mkString
    val parity = digits.size & 1
    val total: Int = digits.zipWithIndex.map {
      case (c: Char, i: Int) =>
        val digit: Int = c.asDigit
        val result: Int = if ((i & 1) != parity) digit << 1 else digit
        result / 10 + result % 10
    }.sum
    val tenComplement: Int = (10 - (total % 10)) % 10
    tenComplement == code.last.asDigit
  }

  def main(args: Array[String]) {
    val isinSg: String = "FR0000130809"
    println(isIsin(isinSg))
    val isinBad: String = "FR1234567898"
    println(isIsin(isinBad))
  }

}