What's the Scala recipe for reading line by line from the standard input ? Something like the equivalent java code :
import java.util.Scanner;
public class ScannerTest {
public static void main(String args[]) {
Scanner sc = new Scanner(System.in);
while(sc.hasNext()){
System.out.println(sc.nextLine());
}
}
}
The most straight-forward looking approach will just use readLine()
which is part of Predef
. however that is rather ugly as you need to check for eventual null value:
object ScannerTest {
def main(args: Array[String]) {
var ok = true
while (ok) {
val ln = readLine()
ok = ln != null
if (ok) println(ln)
}
}
}
this is so verbose, you'd rather use java.util.Scanner
instead.
I think a more pretty approach will use scala.io.Source
:
object ScannerTest {
def main(args: Array[String]) {
for (ln <- io.Source.stdin.getLines) println(ln)
}
}