Iterating through command line arguments in Scala

for {
  i <- args.indices.drop(1)
  if args(i) startsWith prefix
} printf("args(%d): %s\n", i, prefix)

or

args.zipWithIndex
    .drop(1)
    .filter {case (s, i) => s startsWith prefix}
    .foreach(arg => println("args("+arg._2+"): "+arg._1))

or

for {
  (s, i) <- args.zipWithIndex.drop(1)
  if s startsWith prefix
} println("args("+i+"): "+s)