// 
// program to sum integers from file, with simple handling of errors
//
import scala.io.StdIn._

// "try" this code, going to "catch" if there is an error
try {
  println("enter name of file containing ints")
  val filename = readLine
  val src = scala.io.Source.fromFile(filename)
  val lines = src.getLines.toList
  src.close

  val sum = lines.map(_.toInt).sum
  println("sum = " + sum)
} 
catch { // "catch" specific types of errors
  case fileError:java.io.FileNotFoundException => {
    println("could not open input file")
    println(fileError)
  }
  case nf:NumberFormatException => {
    println("non-integer input in file")
    println(nf)
  }
}