Scala Unit type

Question

I use opencsv to parse csv files, and my code is

while( (line = reader.readNext()) != null ) { .... }

I got a compiler warning saying:

Answer 1

You can use a Stream to get what you want:

Stream.continually(reader.readLine()).takeWhile( _ ne null) foreach { line =>
  //do Stuff
}

This has the added advantage of other cool stuff as well:

Stream.continually(reader.readLine()).takeWhile( _ ne null) match {
  case head #:: tail => //perhaps you need to do stuff with the first element?
  case _             => //empty
}

EDIT - thanks to mkneissl for pointing out I should have included this warning:

scala> Stream.continually(1).take(100000000).foreach(x=>()) 

scala> val s = Stream.continually(1).take(100000000) 
s: scala.collection.immutable.Stream[Int] = Stream(1, ?) 

scala> s.foreach(x=>()) java.lang.OutOfMemoryError: Java heap space