BooleanListToBinary.scala

package object example {
  
  /**
   * Tranverse a seqence of booleans (which it interprets as seqence of bits),
   * and these booleans are transfromed into a binary value. Eg.
   * 
   * scala> boolsToBin(List(true, true, false, true))
   * resXX: Int = 11
   */
  def boolsToBin(bs: Seq[Boolean]): Int = {
    def iter(binSeq: Seq[Boolean], binIndex: Int, acc: Int): Int = binSeq match {
        case Seq()         => acc
        case Seq(x, xs@_*) => iter(xs, binIndex+1, acc | (if (x) 1 << binIndex else 0))
    } 
    iter(bs, 0, 0)
  }
}